| Author | Message | ||
     Joseph DeLautre (Mudderducker) New Member Username: Mudderducker Post Number: 20 Registered: 02-2004 |
With all automobiles, when you increase airflow, you increase horsepower. That is why hotrods have headers and freeflowing exhaust. So there must be a happy medium for a D1 that will make it more responsive and not sound like a TransAm. I am thinking a K&N filter, somehow modify the airbox to get cool air (maybe a hose outside the heated engine bay), and a freeflowing muffler like a glasspack or something while removing the second muffler thing (resonator?) by the rear tire. Will this work to get the truck to be more responsive and still not be too loud to enjoy the outdoors? | ||
| Alan E. Foster (Vt_alan) New Member Username: Vt_alan Post Number: 32 Registered: 11-2003 |
In my experience with Rover engines, true free flowing exhausts make them pretty loud -- I had a Flowmaster w/ NRP cats and snorkle on my D90, and it was loud enough to set off car alarms (coincidentally, the engine sounds really cool when you fire it up with only the manifolds attached) ... or wake up the neighbors when I left for work in the mornings. Not very quiet. Also, the gains from cold air are overwhelmed by the losses in hp from the restrictive nature of a longer intake with more bends. I say, get rid of the resonator, put in a new air filter (I use a K&N and like it, but I've also heard the K&N can be too free flowing, and allow too much crap in, so use at your discretion), and see where you want to go from there. Bottom line, this is a heavy truck, with a small displacemnt V8 -- it's going to be loud long before it feels responsive. I think you'll get more bang from small improvements across the board -- change your fuel filter, update the spark plug wires, put in new plugs, put in a new air cleaner, and cut off the resonator; if it ain't too loud, then look at a new exhaust. This is only my opinion ... | ||
| Steve Turpin (Steveturpin) New Member Username: Steveturpin Post Number: 24 Registered: 01-2004 |
Well, I don't really think there is much you can do, short of an engine swap...I have a K&N and a Borla cat back system in my D2...and it sounds good, and I'm sure it helps add a few hp...but it's not the kind of thing that's going to make a real noticable difference. Keeping the motor running to spec, or doing a larger displacement swap for big bucks is the only real choice... | ||
| Leo (Leo_hallak) Dweb Lounge Member Username: Leo_hallak Post Number: 192 Registered: 02-2003 |
This has been talked about to death. If you have a 4.0 Rover there is not a lot you can do, its not a race car and it weighs a lot. Free flow exhaust and a K&N aren't going to make enough difference that you would even tell. Keep it tuned, run premium fuel, or you can always do a motor swap to a 4.6. If you have changed tire size say to 235/85/16 you can always re-gear it to 4.11 and gain back some of your power. BTW: You can always do a search and you will find a ton of people asking this same question. -leo | ||
| eric johnson (Eric2) Senior Member Username: Eric2 Post Number: 274 Registered: 05-2003 |
J Robison has been posting about good results with the Powerchip, but it's not an "un-plug the old chip - plug in the new chip" operation. It then needs some tweeking by a Roavacom unit or equivalent. He's writing an article about it in the March RN newsletter | ||
| Matt Anderson (Disco01) Senior Member Username: Disco01 Post Number: 276 Registered: 10-2003 |
One thing to consider when doing a free flow air intake, you basically just "leaning" out your engine by putting more air into the fuel mixture. I have often times been skeptical about the power gains here. My thinking is that at first they may add a few ponies but the computer probably adjusts to compensate for more air anyhow. But serioulsy, even if it does not you are gonna make your engine run hotter by leaning the mixture. I dont think it is gonna be anything significant with a K&N though. Also, remember that some exhast backpressure is good, so dont think you can put a true dual setup with 3 inch pipes and expect to gain any power.......quite the contrary, you will lose lots of low end torque.I know I put a freer flowing exhast on mine and it sure does sound faster! Hahaha........but I have no doubts that it really isnt. You could combine a lot of things listed above and probably get a few ponies but I dont think it would ever be enought to justify the cost. Just my $.02, so take it for what it is worth. Matt | ||
| Alan E. Foster (Vt_alan) New Member Username: Vt_alan Post Number: 33 Registered: 11-2003 |
... and, with increased HP comes decreased mileage. | ||
| Timothy A. Green (Tree_trimmer) New Member Username: Tree_trimmer Post Number: 4 Registered: 02-2004 |
I'm running a chip in my 95 D-1 and I have noticed more responsiveness, and worse fuel mileage. But the responsiveness does not equal horse power. I know this when I tow my travel trailer. According to Ian at RPI, the free flowing exhause system is not beneficial without the chip to use that to the engines advantage. He is also adamant about good spark plug wires. I am in need of a muffler and was thinking about going with the Borla to accent the chip. Don't know if I'll notice anything. I didn't notice anything with the K&N when I installed it pre-chip. |
