| Author |
Message |
    
Corey Shuman (One_Bad_Rover)
| | Posted on Wednesday, February 05, 2003 - 12:31 am: | 
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Hey,
Anyone know of a good chip fabricator for the 4.0 Disco 1s. I have heard of people chipping their motors and gettting a ton of HP!! (like almost 40) Any help is appreciated!!! |
Pugsly (Pugsly)
| | Posted on Wednesday, February 05, 2003 - 12:41 am: |
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http://www.rpiv8.com/engine-8.htm#ecu |
John Davies
| | Posted on Wednesday, February 05, 2003 - 10:34 am: |
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That RPi info looks interesting. I don't suppose that the re-mapped ECU is emissions legal in the USA though......
I would be interested in reading an independent test by a magazine or owner, with dyno results (before and after). |
Corey Shuman (One_Bad_Rover)
| | Posted on Wednesday, February 05, 2003 - 11:25 am: |
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Well, anything in the US?? for a 4.0?? damn, bmw chips are a dime a dozen and I cant find a Rover chip to save my ass....): |
Jason Vance (Jason)
| | Posted on Wednesday, February 05, 2003 - 11:30 am: |
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Why wouldn't a remapped ECU be emissions legal?
How would a remapped chip give you extra HP, even up to 40 extra HP (on an otherwise un-modified engine...BTW, K&N and Borla cat-backs don't count as engine modification)? |
Corey Shuman (One_Bad_Rover)
| | Posted on Thursday, February 06, 2003 - 11:57 am: |
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Remapped chips are remapped to remove alot of the emission restrictions and engine saftey features, such as redline limits etc..remove these and you get quite an different beast out of the same engine. Also that is why sometimes remapped chips are illegal, puts out a little too much emissions etc... but I think they should be more worried about that old Camaro down the street that belches out the nasty black smoke instead of my disco... :D |
Al Oliveira (Offroaddisco)
| | Posted on Thursday, February 06, 2003 - 12:06 pm: |
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FWIW, my BMW M Roadster (3.2L 6 cyl) put out more emissions than my 1999 D2. And on the Roadster I could `chip' it and get an extra 20 hp and still be legal. |
Jason Vance (Jason)
| | Posted on Thursday, February 06, 2003 - 02:30 pm: |
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Again, I ask why would they be illegal (or maybe, why you would get caught)?
Your DMV inspector doesn't know a remapped chip from a potato chip, so fat chance that somebody is going to eye-ball your ECU, tag or impound your vehicle (unless you were dumb enough to remove your cats).
Remapped chips provide more fueling where it is needed and less fueling where it is not necessary. I don't see a remapped chip putting out more emissions at idle. I also don't see a remapped ship putting out more fuel at a steady-state rpm (like 2500 or so) where many of the the smog sniffer tests are performed. The chip should even optimize the fuel that the engine is receiving at a steady rpm, leaning it where appropriate, which would further ensure that the fuel was completely burned in the combustion chamber (and granted your cats still work...).
The ECU is only providing the function of a complicated carburettor with a feedback mechanism to do what a carb cannot...that is, adjust the air-fuel mixture.
Your gains in power are through appropriate leaning of the mixture where applicable, as well as maximizing the acceleration circuit. Keep in mind that a car running rich produces less power than a car running lean (up to the point of detonation). And finally, if your ECU incorporates the control of ignition timing, a remapped chip could potentially maximize the advance which can also deliver more power up to the point of detonation.
Sorry...a BMW with overhead cams racing up over 6500 rpm can benefit from eliminating redline restrictions, can probably benefit from a modification in the acceleration circuit, etc. to porduce more power and enhanced drivability. Your Disco with peak HP at 4500-4600 rpm and a shift point (with an automatic) at 4200-4300 rpm probably won't benefit from an increased red-line limit (and why push it with a pushrod and weak valve-springs...)...read RPi sites and their claims...I certainly believe them a lot more than a company claiming "loads of HP."
BTW, last time I read an article from a reputable car mag on a remapped chip, all it did was eliminate the redline and governor...no gains in power (it was a Bimmer and it was a Dinan chip...).
I'll just sit here an play the devil's advocate a little longer... |
peter j. kelly
| | Posted on Friday, February 07, 2003 - 10:42 am: |
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I did the rpi chip on my 94 D1 NAS...passed emissions easily and the motor had the piper cam added to...did it all myself...it was a very nice motor!
Pete |
Andrew Clarke (Aclarke)
| | Posted on Friday, February 07, 2003 - 03:27 pm: |
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The chips I know of that make the most difference are chips for turbo motors. There you can easily increase the turbo pressure and suddenly you have more power. The Dinan chip they sell for my 2001 Z3 3.0i coupe (car's for sale if you want to buy it!) doesn't actually provide any more power, like Jason said. So Al I guess you're lucky (in more ways than one, haha) that you have the M over the plain 'ole Z, or let me know where you got that chip!!
APR (www.goapr.com) reprogrammed ECUs are an easy way to add ~50hp to your VW/Audi/Porsche turbo engine for $400-500. They also have various modes like "Valet" that keeps engine power down and another mode for when you take it to the dealership, smog check, etc. where it looks like a stock engine. I expect that if you can get a chip for your Rover it might have a similar mode. |
Jason Vance (Jason)
| | Posted on Friday, February 07, 2003 - 04:00 pm: |
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Now we are getting somewhere.
Turbo = more air.
More air + more fuel = more power.
If you are not significantly changing the way your engine is breathing (e.g. increasing displacement, porting heads, turbo, etc), you are not going to gain power from a remapped chip.
The exception, obviously, is an EFI system that is underbuilt for the requirements of a hi-performance engine (this sounds like what I'm hearing about the BMW M engines...and Andrew's example with increasing the boost on a turbo engine is a no-brainer).
Keep in mind that the Rover V-8 is a not a hi-po engine (the basic design has not changed since the early 60's...it's a pushrod for pete's sake)...it's not like there is a load of untapped potential in there just waiting for an electronic signal...and the Lucas ECU is perfectly adequate supplying fuel to the engine in STOCK form. |
Ali
| | Posted on Friday, February 07, 2003 - 07:34 pm: |
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I contacted an hi po shop in San Diego to see what they'd charge to reprogram a typical LR ECU. I about shit when he said around $1200 and they'll need the car too. I still like the Mark Adams reprogrammed chip that RPI uses but for $800 it's a serious chunk of change. But like they say.."you can go only as fast as your wallet allows"! |
Jason Vance (Jason)
| | Posted on Friday, February 07, 2003 - 08:21 pm: |
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(shaking head)
For 800 to 1200 dollars, I can think of a whole number of things that could net some noticable HP (and much more importantly, torque in the lower RPMs where it is needed) besides putting a chip in an otherwise stock Rover.
Does anybody still remember how to modify an engine? Just 'cuz the carburettor was replaced by a computer and injectors doesn't mean the same tricks don't still apply... |
RJ Clayton (Tozovr)
| | Posted on Friday, February 07, 2003 - 08:30 pm: |
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OBDII Beemiers are Notorious for counteracting almost any mods period...chipped or not. Turner Motorsports, down the street from me has just released a chip that has overcome the OBDII Nazis...Steve Dinan is on his way as well...
Now. The reason a chip is not emisions legal is because it will change fuel and spark maps. Now you can essentally DUMP fuel in there and make more hp...to a point. You unburned hydrocarbons skyrocket. You wast quite a bit of fuel.
Look at you local Rice rocket...say an FZR1000...the bike may get decent mileage but you're comparing it to a car...look at the mileage versus displacment for that motor and the fuel ecomomy is atrocious! HORRIBLE....when you chip most (most I say) vehicles that is a result. And CARB and the rest do not want to see that.
You will not see a 40hp gain from a chip on a non turbo vehicle. I'll even go further out on a limb and say that unless the wastegate on said turbo is electronically controlled (1.8T VW's and Audis), you won't see near 40...
In the mid to late 80's and the early 90's you saw many GM based cars getting 20+hp from chips....this was because, back in the day, the cars were tuned so conservatively from the factory, by simply adding some fuel and spark, the things really responded well.
I really must say I think Chip manufactirers are riding on the coattails of the crappy old days.
There are a few guys selling them for the 4.0 jeep currently. The 4.0, like your V8 4.0, has been well setup from the factory (after all these years of production, it would seem as though we're at the ceiling of hp, without more displacement...or other aftermarket mods...) By merely "chipping" it, you're just gain HP to weight advantage by lightening your wallet.
RJ |
Keith Kreutzer (Revor)
| | Posted on Friday, February 07, 2003 - 09:31 pm: |
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Cams are nice! I'm told a mild cam will not piss off the GEMS ECU.. A little polishing here and there would help... How bout a riser on the intake to lengthen the intake runners for more torque... If it would fit under the hood... Even inside the plenu, Tubes or stacks if you will, would make the runners longer. Figure out an adjustable fuel pressure regulator... Headers... These are all on my list... We may think OBDll is too sensitive for the adjustments but i can't believe it... Otherwise i couldn't drive at 10,000 feet and 0 feet above sea level.A cam and some heads with one size bigger valves would cost probably $1200 if you did the underhood work yourself.
When all else fails spend the $$$$ on a bigger engine |
Jason Vance (Jason)
| | Posted on Saturday, February 08, 2003 - 12:52 am: |
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Keith you are my hero! |
Keith Kreutzer (Revor)
| | Posted on Saturday, February 08, 2003 - 01:15 am: |
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I'm Flushed Jason..
But it does drive me crazy to think about all this business of remapping and electronic wizardry that gets us a zillion extra HP.. Fuel atomization and scavenging aside, An engine is a pump.. a pump in one configuration can only move so much air... More air is more power as you can burn more fuel.. The only way to make the pump move more air is to change the configuration.. Of course forced induction and nitrous don't count here... Our little Disco motors are built in a rather wheezy configuration as a pump so if we want more power we need more air!!! And there are only so many ways to do this... |
RJ Clayton (Tozovr)
| | Posted on Saturday, February 08, 2003 - 01:36 pm: |
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Quote:But it does drive me crazy to think about all this business of remapping and electronic wizardry that gets us a zillion extra HP.. Fuel atomization and scavenging aside, An engine is a pump.. a pump in one configuration can only move so much air... More air is more power as you can burn more fuel.. The only way to make the pump move more air is to change the configuration.. Of course forced induction and nitrous don't count here... Our little Disco motors are built in a rather wheezy configuration as a pump so if we want more power we need more air!!! And there are only so many ways to do this...
Well SAID!!!!!!!!! Bravo!!!! Bravo!!!
Roller rockers, a cam....lets get dirty! |
Corey Shuman (One_Bad_Rover)
| | Posted on Saturday, February 08, 2003 - 03:42 pm: |
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Im gonna have to disagree just off of what I have seen so far, I have a 93 318is(4banger) no turbo or anything, and when I added a Conforti chip(thats where TMS gets theirs from) there was a HUGE difference over stock, my low end was extremely more reponsive I gained a top speed of 140mph+ (got scared at 140) AND my gas mileage went from 24-25 per gallon to 32-33 per gallon. This is what a chip remapping should do. Now this is an OBD I but on my 98 M3 which is OBDII I got similar results. Cams, Roller rockers, port/polish job etc... arent going to do anything for you if the computer wont work with them. As much as it may suck the place to start now is at the computer and work back. If you arent willing to do this then you need to get a Series or something with out a computer. This is common sense. BTW, Im not looking for a Disco that can race my bimmers just looking to see if I can up my milage and torque while Im at it. Y'know. oh, And OBDIIs are very sensetive, they will self adjust to a point, which is why you can drive at different altitudes but does your vehicle drive the same way at 0 as 10000, I doubt it. Also the reason I brought the bimmer(quick lesson, bimmer=car, beamer=bike) into this is because of BMWs integrations into LRs, Im justwondering if the computer configurations are similar....Im going down to Eurosport on monday to chat with Jim Conforti and probably take a look at the mapping on my chip. I'll let you all know what I find out. |
RJ Clayton (Tozovr)
| | Posted on Saturday, February 08, 2003 - 04:17 pm: |
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That's why I said OBDII. Still on OBD1 rigs, at this state of their evolution (farther on in the grand scheme of things...been really optimised over the years...such is the 4.0 Rover and the 4.0 Jeep mill) You wil not see the big numbers Mfg's claim.
One things a chip can do it truly improve driveability...on my '89 SHO I lost 3 HP on the dyno (DynoJet 248c) but the driveablity was sooo much better. The Chip got rid of the rev limiter and opened the shorter intake runners 600 rpm's earlier. It drove better and felt faster...but it wasn't (Checked at New England Dragway).
Many folks spout Shit about HP and mods. ESPECIALLY the aftermarket. SHow me Honest to God Dyno numbers (done with the hood shut, the A/C off etc....) and I'll beleive what they say. Till then the BS they SPEW makes me ill.
RJ |
Al Oliveira (Offroaddisco)
| | Posted on Saturday, February 08, 2003 - 04:30 pm: |
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I doubt Jim will want to touch the 4.0 or 4.6 Land Rover engines. The new Rangie with the BMW 4.4l is another story. It's the same engine found in the E39 540i and E53 X5. On a side note BMW upgraded the mapping on those two engines to get 8hp more in 2002 or 2001. The new Rangie engine (I think) still has the old mapping.
Jim C. gave me a good explanation how you can get more HP by remapping. It partially had to do with the way the OBD used the Oxygen Sensors but it's been years and I don't remember the details. |
Jason Vance (Jason)
| | Posted on Saturday, February 08, 2003 - 07:55 pm: |
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Tell me what Roller Rockers are going to do for HP, and how the stock ECU can't handle them.
Seriously, some stuff mentioned here makes some sense, but there is a lot of BS floating around. You either know how it works or you are reading advirtisments.
Comparing bimmers to Rovers are like comparing apples to oranges. BMW = overhead cam engine, modern cylinder head design, can be driven well towards redline and benefit from it. Rover = pushrod engine, ancient head/cumbustion chamber design, auto-t.ranny shifts before peak HP is reached.
Here's a lesson, torque is dependent on the engine's displacement and Brake Mean Effective Pressure (this is the average of cylinder pressures across all four strokes). You can either increase your engine's displacement to increase torque, or you can change factors that affect BMEP (compression ratio, air-fuel volume, air-fuel mixture, ignition timing, etc.).
That's it. The only way you can change torque is displacement, CR, how much the engine breathes, and what the engine breathes.
Richen the air-fuel mixture and you lose BMEP. Lean the A/F and you increase BMEP but risk detonation. OBD-1 on Rovers do not have a knock sensor BTW. Your OBD-II does have knock sensors and can retard timing. You tell me...what benefit do you gain by increasing BMEP through leaning the A/F mixture only to have to retard the advance on your timing to prevent detonation? You're not gonna find that answer on any box of cereal.
HP is a function of torque and the engine's RPM (HP = torque * RPM / 5252). To increase HP you have to increase torque at each RPM point. Read the above.
BTW Corey, you go from saying that you've "heard about people getting almost 40 HP of a chip" to saying you have experienced some sort of gains from rechipping your own car. Hmmmm...the learning curve must be slow around here.
Go back and read RPi's site and their claims. Keep in mind they use the Rover V8 and modify it's use in TVRs...I think they know their sh*t and when they fail to claim any kind of torque/hp gain when their chip is used with a stock engine, it's probably from experience with the Rover V8.
Take it for what's it's worth. Me, I'm gonna be busy screwing up my ECU by using some roller rockers.
BTW, Keith, you nailed it! The engine is only an air-pump! |
RJ Clayton (Tozovr)
| | Posted on Saturday, February 08, 2003 - 11:03 pm: |
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Quote:Tell me what Roller Rockers are going to do for HP, and how the stock ECU can't handle them.
WHAT? Who said that a stock ECU can't handle roller rockers?
And they free up HP by reducing friction...
The ECU's in the BMW's, due to OBDII, will change settings to retain original performance. It's been very difficult, until recently to squeez and HP out of the cars due to that.
No one ever said that the Rovers would react the same way...unless I missed something.
Chips are bunk in may applications these days...wanna make HP? You need to go internal (cam, roller rockers, valves, headwork...blah blah). A chip may augment those mods (due to stock parameters being adequate) but will not replace them.
RJ |
Keith Kreutzer (Revor)
| | Posted on Saturday, February 08, 2003 - 11:16 pm: |
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Here is a good example of Chipping.
I have a 97 Ford F350 Diesel.
In Colorado we are required to put these things on a Dyno for emmisions... In the test they don't care about HP just load, but they can read it...Where i have my truck tested i know the guy well (been giving him $65 a year for nothing for nearly 10 years!!!!) So he lets me play a bit and watch the numbers.. Chip out, some 200 HP and 300 somthing Ft pound of torque chip in a significant gain of 20 HP and 70m ft pounds wow!!! BUT!!! the thing is pouring black smoke and will NOT pass emmisons with the chip... Go put on the stuff that can UTILIZE the extra fuel new exhaust (4.5") a bigger turbo and the gains go through the ROOF!!!!(with and without the chip) and it will pass emmisions but now it's detonating so badly with the chip I would need to install bigger injectors to get enough fuel in the cylinders to prevent it and the exhaust gas temps as skyrocketing with the chip.. The injector timing on the chip is fucked too advanced... In the end the "normal" things i did to the engine to make it breath better did more for performance and longevity than the chip! And without the chip or the the stage 1 injectors I pass emmisions, have lower EGT's and have goobs of power.. Great right!
Well funny thing i used to be able to start from every stop in second gear... Now? It's mostly first.. Just like that old Barracuda put on the 750 holley over the 650 and the holeshot is gone... Bigger holes mean less torque down low. Advance the timing to get it back and you detonate... It's all a trade off and chips well they do silly things like fool sensors to think it's cold out side so the car runs richer and advances the timing...Beats the cats to death! What does a rich running engine do to itself? washes the oil off the cylinder walls. Those chips that actually "remap" might "optimize" things a bit towards the "peppy" end of the spectrum but any extra is IMO pushing it too far. |
Randall Smith
| | Posted on Saturday, February 08, 2003 - 11:37 pm: |
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Have you guys have been breathing exhaust fumes?? |
Keith Kreutzer (Revor)
| | Posted on Saturday, February 08, 2003 - 11:40 pm: |
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As much as possible |
Todd Phenneger (Toddp)
| | Posted on Sunday, February 09, 2003 - 04:53 am: |
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Has ANYONE ever CONSIDERED, if even for a moment, putting twin turbo's on our Rovers. We have oodles of room down there. My only worry would be river crossings but for a street rover,could be nice. We haveroom for everything, IF we could adjust the ECU parameters. Hmmm, Wolf 3D is looking better all the time. :-)
A Friends VW/AUdi tuning shop,
www.achtuning.com
Does a lot of VW-Audi tuning. So my thinking is that if I grabbed a couple old K-03 Turbo's they had laying around and set them up for a mild 6-8psi boost that may make for a nice modification. Just a thought.
I KNOW its more difficult than this, I'm summarizing. I've done enough conversions to know better. Just wondering if anyone has pondered it besides me?
l8r
Todd |
Jerry (Discovery1)
| | Posted on Sunday, February 09, 2003 - 05:25 am: |
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Hi:
Superchips makes chips for Discoverys. The cost between $380 and $480. They claim that they add another 20 plus horsepower.
Thanks |
Ali
Unregistered guest
| | Posted on Sunday, February 09, 2003 - 10:45 am: |
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Jaon,
As you said earlier (shaking your head) chipping isn't the only solution. I too am going the 4.6 route for bigger displacement. BTW, I remembered the name of the company that does rechipping in Oz...it's Unichip. The only unichip dealer is the one in SD. It was simply a "curiosity" phone call to them to see what people charge for rechipping these days.
Anyway, going back to the great debate here: according to RPI, simply gaining more displacement yields the need for more air and fuel. Well, getting more air isn't much of a problem, ie. head work, filter, perhaps a RP4 camshaft. Some people are shortening their trumphets (more on this later). RPI does recommend the need for a remapped ECU to allow more fuel to go with the additional air. Their ECU simply extends the duty cycle for the stock injectors so more fuel is dumped in. Of course this can be achieved cheaply (less scientifically) by using a rising rate fuel press regulator to increase the pressure. If I understand this correctly, higher press means more fuel for the same duty cycle (injector on). Now correct me if I'm wrong here, the 4.2 chip (for less than $50) has a longer duty cycle than the 3.9 chip, is this correct? Is this why the 4.2 chip being talking about as a cheaper alternative? How about the 4.2 chip along with the rising rate fuel press regulator? Combined, this is still lot less than a RPI ECU.
Shortening trumphets - this procedure eludes me. Few people have shortened them by one inch and are claiming to have more torque. This is contradictory to me as this should cause less torque at lower rpms. I'd think lenghtening the trumphets is what we'd want for low end torque. I can understand a TVR needing higher revving engine, therefore, shortening is necessary. But can't understand why we'd want to do this on a rover. Perhaps just getting more air, regardless of the velocity, is all a larger engine is needing?
Most 4.6 conversions I've talked to, they've all experienced at one time or another, hotter than normal running engine temp. This is due to running "lean" condition, which is a deadly situation. Some solved this by RPI chip and others by trial and error and with messing with the 4.2 chip and adjusting the fuel press regulator.
Sorry for the long post.
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Jason Vance (Jason)
New Member
Username: Jason
Post Number: 260
Registered: 04-2002
| | Posted on Sunday, February 09, 2003 - 02:00 pm: |
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Ali, good questions!
WRT shortening the trumpets, yes this is counter to the convention. However, I believe the increase in torque is only due to removing some restriction in the plenum by getting the opening of the trumpets away from the ceiling of the plenum. While increasing trumpet length should lead to an increase of torque, as mentioned earlier in this thread, you need some spacers of sort to make the plenum higher.
The only reason why more torque comes from longer intake runners is the functional momentum of air entering the combustion chamber, especially at lower RPMs where the vacuum can be slightly mudded by valve overlap and low port velocities. But if an increase in air demand is impeded by resistance from the air changing direction within the plenum, then you can benefit from shortening the trumpets (reducing air restrictions) both in the torque and HP department. Basically, just physical limitations and compromises.
Going back to the 4.2 chip questions...if you are running OBD-I this is a very reasonable solution. The rising-rate fuel pressure regulator has the potential to push the fuel-delivery into the "rich" area and not run the injectors high into the duty cycle (basically pushes the fuel flow back within the programmed parameters). The only area where a problem may still occur is at high RPM...which I don't think is enough of a consideration WRT Land Rover driving habits.
My main beef with the chip (and as other's have mentioned) is the mentality that the chip is going to open a pandora's box of unleashed engine potential. Not the case, especially with the stock Rover engine. A remapped chip will enable the ECU to function under the new parameters...that is, WHEN YOU MAKE THE MODIFICATIONS; and that's not saying that certain modifications will function at times within the parameters of the stock ECU. |
Jason Vance (Jason)
Member
Username: Jason
Post Number: 261
Registered: 04-2002
| | Posted on Sunday, February 09, 2003 - 02:05 pm: |
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Todd,
twin turbos sound nice, but some people have mentioned poor results with simply supercharging the engine. There appears to be issues with the Rover engine having a weak bottom end.
The cross-bolted 4.0 and 4.6 may be a thought, especially since the main journals are larger than the 3.9/4.2's.
While the thought is good, it requires a complete redesign of the engine, replacing weak components with some quality forged parts.
BTW, I recall one of the BOP 215's being turbocharged from the factory. Albeit this was with an aluminum block made from a weaker alloy, but still produced about 180 hp in that trim. Food for though, if your hungry! |
Ali
Unregistered guest
| | Posted on Monday, February 10, 2003 - 05:36 pm: |
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Jason,
So it sounds like you're for the 4.2 eprom but not the fuel press reg? I guess the only way to tell if the eprom alone will do the trick is to check the o2 contents while running. My thought is that running richer perhaps is better than the opposite.
WRT to the trumphets, I like the idea of creating a spacer to make more room. Those trumphets are in there with resin or some super duper adhesive. By creating a spacer for the housing, one can find out the optimum spacing for his specific engine. Shortening the trumphets is a one time thing and makes me nervous. |
Jason Vance (Jason)
advanced member
Username: Jason
Post Number: 264
Registered: 04-2002
| | Posted on Monday, February 10, 2003 - 08:00 pm: |
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Ali,
The rising rate fuel pressure regulator can be helpful to push the injectors back down within their duty cycle.
Hypothetically (numbers are made up to illustrate the point), the injectors can be held open for 20ms max for every injection cycle. At max fuel pressure with the stock regulator at 4300 rpm, the ECU is keeping the injectors open 19ms per injection cycle to supply enough fuel to the engine. If you increase the engine RPM to 4500, the injectors are maxxed out for injection duration, and further RPM increase leads to a lean A/F mixture.
The rising rate fuel pressure regulator allows the fuel pressure to increase so that at 4300, the injector only has to stay open for 15ms to inject the same volume of fuel, and at 4500 rpm, the injectors are still under max opening time.
Again, while the above situation is hypothetical, WRT to injector opening time and relative duty cycles, the point is the rising rate fuel pressure regulator allows for the same volume of fuel with a shorter injection duration. This ultimately will allow the ECU to continue metering and adjusting the A/F mixture instead of simply running lean when the fuel pressure and injector is maxxed out.
Is this a band-aid? Kinda...but it is effective and sure beats engine damage. Again, like a chip, not much to be gained unless modifications of the engine demand it. |
RJ Clayton (Tozovr)
Member
Username: Tozovr
Post Number: 292
Registered: 09-2002
| | Posted on Tuesday, February 11, 2003 - 12:54 am: |
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Jason, isn't it true that it's best to have the injectors running at about 70% of their design rating for max efficiancy (past 70% you lose efficiency due to incorrect pulse lengths)?
Would an adjustable fuel pressure regulator solve that? Why not just bigger injectors?
I'm not sure what #/hour the rovers are rated at.... |
Jason Vance (Jason)
advanced member
Username: Jason
Post Number: 266
Registered: 04-2002
| | Posted on Tuesday, February 11, 2003 - 02:23 am: |
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quote:Jason, isn't it true that it's best to have the injectors running at about 70% of their design rating for max efficiancy (past 70% you lose efficiency due to incorrect pulse lengths)?
Yes, that was the point of the post above. I don't know the exact number, at it varies with the type of injector, flow-rate, etc.
quote:Would an adjustable fuel pressure regulator solve that?
A static adjustable regulator, or a rising rate regulator? The fuel pressure regulator increases fuel pressure with a decrease in manifold vacuum. e.g. when at low rpm (1500) you floor it...manifold vacuum immediately decreases, and the fuel pressure increases (in conjuction with the ECU increasing injection duration) to provide more fuel volume for the acceleration circuit. This example is analgous to the accelerator pump on a carb; only on EFI, it's controlled mechanically by engine vacuum, and electronically by air-flow (mass air meter), load sensor (throttle potentiometer), and A/F mix (oxygen sensors).
A static regulator would increase fuel pressure across the board, which still demands a broad range of injector duration to meter fuel volume, and also may cause the injector to run hotter due to operating under a greater load (the solenoid mechanism has to overcome the pressure behind the valve). The rising-rate regulator works like the stock regulator but continues to increase fuel pressure as the manifold vacuum approaches atmospheric. Basically, it functions like stock under normal driving conditions, and when the hammer is down, it continues to increase pressure to produce enough flow to enrich the acceleration circuit and not peak out the injector's duration (for that required fuel flow)...and the ECU is *usually* none the wiser.
quote:Why not just bigger injectors?
Why not? It's a great idea and the way to go when completely rebuilding/modifying your engine. Kinda like changing jets on a carb! This is ideal especially when the engine's demands exceed the stock injector's flow rate, even at higher fuel pressures. The rising rate regulator may work fine up until the point the stock injector will not flow any more volume...then the engine runs lean. The rising rate regulator is a perfectly good choice as long as you consider the limitations...when the limitations are exceeded, bump up to greater flowing injectors.
quote:I'm not sure what #/hour the rovers are rated at....
Neither do I. Take home message...it's all about balance and minimizing compromise. Consider what changes modifications will create on the flow of air and demand for fuel in your engine, and change what is needed...ECU chip/fuel map, fuel-pressure regulator, injectors; just make sure no single choice favors one RPM or operating range over another. |
Ali
Unregistered guest
| | Posted on Tuesday, February 11, 2003 - 12:07 pm: |
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I suspect that the stock injectors will do fine for my needs. I'm not blowing or turboing nor demanding 400 hp out my little block. I read somewhere that most injectors have a life span of 80k miles. After that, it's a good idea to replace them but at least have them cleaned and flow tested. At around $80-$100/injector, I think I'll have mine tested and cleaned before purchasing new ones! |
Corey Shuman (One_bad_rover)
Member
Username: One_bad_rover
Post Number: 67
Registered: 09-2002
| | Posted on Tuesday, February 11, 2003 - 05:10 pm: |
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ah, this thread has gone to hell...Just wondering about chips and what they may or may not do, BTW, I mentioned that I had heard of gains of 40hp..IN A DISCO....NOT A BIMMER and that was on a diesel Disco, appearantly you cant pull that out of a gas powered beast. As for the rest of the new motor, get twin turbos etc... Thanks!!, I really appreciate it. I was considering dumping a few thousand into my motor which is why I was looking into a chip(see sarcasm above)
My opinion is if you want to tweak a motor get somthing that you can actually play with, a old chevy or the like....anything else you are wasting your time. Rover, BMW etc...dump billions, yes billions into designing these engines, Im betting that at least one person on the team has had the ideas you suggest and for some strange reason they were disregarded, draw your own conclusions to that. But if an engine were just a big air pump we would all still have cowl induction and blowers would be be the norm...after all thats the best way to improve on air flow, right, those fools at the auto makers, they should come here for advice on how to build their motors..... |
Jason Vance (Jason)
advanced member
Username: Jason
Post Number: 267
Registered: 04-2002
| | Posted on Tuesday, February 11, 2003 - 07:13 pm: |
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It's too bad you didn't learn anything, Corey. Your attitude is even worse.
BTW...I loved this one:
quote:*Rover*, BMW etc...dump billions, yes billions into designing these engines
Maybe you need a history lesson...don't listen to me. Go figure it out for yourself so you will at least respect the knowledge you've gained.
I'll give you a hint...Buick 215 and early 1960's. |
Corey Shuman (One_bad_rover)
Senior Member
Username: One_bad_rover
Post Number: 68
Registered: 09-2002
| | Posted on Wednesday, February 12, 2003 - 05:59 pm: |
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Jason, Im well aware of what the motor is, are you saying that there has been no design modifications since they fisrt started dropping motors in?? Thats like saying that a chev. 350 from 1970 is the same as the 350s of today. CID they maybe close but that is mostly it, the block is the same and yeah, you can swap heads too. but why dont you try to dump a an old buick 215 into one of todays discos... it wouldnt work, too many sensors etc.... hmmm. imagine that, its not the same....!! Most any car company devotes millions of dollars each year into R&D, when they do come out with a new motor design or change something it is a huge event, they have thought of economy vs ride quality vs power vs dependability. Usually you can sacrifice a little dependability for power or torque. Hence a chip remap, and they are all dialed down, the most basic remap just overrides the ability to use cheap gas, if you only use 91 octance and above you can safely squeeze out some more power, but if you use less than 91 it will start to knock, hesitate etc... so Rover, BMW etc compensate for this by mapping the chip down to accept a lower grade and still run equally well. do your homework on that one. it true!! The point is I was trying to see if there was a chip that was beneficial to the disco. Im not trying to have a poor attitude but I have building hipo motors for years, I can pull 800 hp out of a naturally aspirated 454 but thats not really the issue. I was simply looking for info on a chip. If you dont like chips Im cool with that. I have seen good things out of them and hence I was wondering if there was a preferred manufacture company. sheesh..... |
Steve (Steve2)
New Member
Username: Steve2
Post Number: 1
Registered: 09-2002
| | Posted on Wednesday, February 12, 2003 - 06:43 pm: |
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hey all
i gotta say the disco gems motor is not one that is a good tuner motor. chipping a disco with undoubtedly cause stress somewhere else in the system. the factory has the intake and exhaust balanced for response and mpg.
to make a 4.0 disco 'faster' stick 4.10 gears in it. then it will haul.....
for the money spent on a cam and a chip - you'd be close to the cost of gears anyway - and then might as well install lockers and use the disco for what it was intended.
sorry but to me chipping a disco is like putting mud terrains on a 7 series bmw for better traction !!!!
WHY? |
Jason Vance (Jason)
advanced member
Username: Jason
Post Number: 271
Registered: 04-2002
| | Posted on Wednesday, February 12, 2003 - 08:14 pm: |
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quote:but why dont you try to dump a an old buick 215 into one of todays discos...
I did the opposite. I took a newer EFI system and bolted it onto my 3.5L '83 RRC. It took me around 6 hours to pull the EFI off the donor vehicle and bolt it onto my engine...from mass-air sensor to oxygen sensors, computer to harness. I could have done the exact same thing to an early 60's Buick.
An early 60's Buick long block won't bolt right into your GEMS equipped Disco...but not because of the sensors, not because of the induction, heads, or exhaust, but because of slight little changes Rover spent "BILLIONS" on when they redesigned the 3.9 into the 4.0 (hmmm...the timing cover...maybe the flex-plate, too). It would run...just a little hot until I got the timing cover fitting properly...BTW, that Buick 215 would drop into any RRC or Disco 1...and if you want to talk straight engines, who said we have to fuel-inject it?
I figure as much time as you will spend bickering about different timing covers, water pumps, or ancillaries, is the same time I waste at Autozone trying to get the monkey behind the counter to look up a part number for a '63 Skylark so I can fit it on my Rover.
quote:it wouldnt work, too many sensors etc.
I'm finished with this thread. Yes it has turned into a train wreck; yes it has turned into a pissing match.
I'll leave you with this...if the quote above reflects your knowledge of engines, in particular the Rover V8, then nothing I could say would ever be of any use to you. |
Andrew Clarke (Aclarke)
advanced member
Username: Aclarke
Post Number: 233
Registered: 10-2002
| | Posted on Wednesday, February 12, 2003 - 08:41 pm: |
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Corey, it sounds like you feel the thread should be all about you because you started it. Well I guess that's a philosophical argument I disagree with in this case.
Yes, it's possible that there might be a chip out there for the Tdi or Td5 that produce somewhere in the neighbourhood of 40hp gains. The "T" in both of those engine designations stands for .... turbo which as I think we've already established makes it much more simple to extract power gains. |
Corey Shuman (One_bad_rover)
Advanced member
Username: One_bad_rover
Post Number: 74
Registered: 09-2002
| | Posted on Friday, February 14, 2003 - 02:04 am: |
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hey all sorry if I came off as a dick, not my intention at all, just that so much random crap being spewed, some of it good and some of it bad...got a little irritated...my bad... but Jason Ive got to say there are people who may be more knowledgeable than you are... my quote above does reflect my knowledge of motors, maybe not Rover V8s but that is because a Rover V8 wasnt meant to be modified(although I will say that I am amazed that LR hasnt made any holes etc... in the block for sensors of any sort). which once again brings me back to the original post about if anyone knew about chipping the motor. |
George Clayton (Offcamber)
New Member
Username: Offcamber
Post Number: 54
Registered: 09-2002
| | Posted on Friday, February 14, 2003 - 08:29 am: |
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Wise man once say......
You can't make a race-car out of a pig, but you can make a quick pig.......... |
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