ok, here's one: cam timing?

[ratboy]

im building a 4.0 and using a crower 258 cam. the specs say the cam is good for 1500 and up. if i screw with the cam timing, i can(supposedly) move the power band around a bit. i was thinking of 4 degrees of advanve to try to get the cam to come around sooner. has anyone played with the cam timing of an aftermarket cam? im putting a 96 motor in a 95. currently auto, but a manual conversion will follow at some point(i want one ok?)
i was wondering what you guys might have for experience.

ok

go!

 

[ptschram]

call and ask Mark at D&D

 

[ratboy]

i am going to, i just wanted a more broad(brunette not blonde, please) input.

 

[CandiMan]

im building a 4.0 and using a crower 258 cam. the specs say the cam is good for 1500 and up. if i screw with the cam timing, i can(supposedly) move the power band around a bit. i was thinking of 4 degrees of advanve to try to get the cam to come around sooner. has anyone played with the cam timing of an aftermarket cam? im putting a 96 motor in a 95. currently auto, but a manual conversion will follow at some point(i want one ok?)
i was wondering what you guys might have for experience.

ok

go!

If valve timing adjustment is possible, wouldn't it be on the crank sprocket instead of the cam?

 

[92rrrandall]

Mr Ratboy

I have checked the timing on just about every camshaft ever made for a Rover V8. It would be very hard for you to find a camshaft that is better matched to a Land Rover than the Crower 229(you call it 258).

The cam you are refering to is already had it lobes ground with 2.5degrees of advance. That means that the lobe centers have already been rotated from center by that much. All you have to do is install the cam using the keyway slot marked "0" and you have some advance.

Advancing the cam lobes by 2.5degrees will cause the torque curve to shift downwards by ~100rpm. It will also allow for some wear in the timing chain in the future.

The only problem with Crower (and almost every other aftermarket cam) is that there is no relief for the cam retainer. I make the cut myself on a lathe. Very easy to after you have done it the first time.

Randall

 

[ratboy]

Mr Ratboy

I have checked the timing on just about every camshaft ever made for a Rover V8. It would be very hard for you to find a camshaft that is better matched to a Land Rover than the Crower 229(you call it 258).

The cam you are refering to is already had it lobes ground with 2.5degrees of advance. That means that the lobe centers have already been rotated from center by that much. All you have to do is install the cam using the keyway slot marked "0" and you have some advance.

Advancing the cam lobes by 2.5degrees will cause the torque curve to shift downwards by ~100rpm. It will also allow for some wear in the timing chain in the future.

The only problem with Crower (and almost every other aftermarket cam) is that there is no relief for the cam retainer. I make the cut myself on a lathe. Very easy to after you have done it the first time.

Randall

i was wondering if the cam had some advance in it allready. as for the retainer, i am not sure if i am going to bother with it. i may make a different retainer or cut the cam, not sure. since advancing the cam will only move the torque curve 100 rpm's or so, i think ill just install it "straight up" as it dosent seem worth the hassle. thanks for the info.

 

[ptschram]

If valve timing adjustment is possible, wouldn't it be on the crank sprocket instead of the cam?

Not necessarily, although it is much more common for the crank gears to be broached for 4' advance and retard. It is difficult, if not impossible to put a vernier adjustment on th crank due to space limitations.

While the Crower 229 is a wonderful camshaft, extensive modeling using Desktop Dyno has shown that the 230 is without doubt the best performing cam in these trucks, all other things remaining equal. Mark and I have discussed camshaft selection at length and he was pleased to hear from me that I had run every cam profile for which I could find data online. I was kinda surprised that some of the more radical cams didn't produce more power or torque, but if you're gonna run a simulation, you ought to believe what it says, if you've put the info in correctly.

 

[ratboy]

Not necessarily, although it is much more common for the crank gears to be broached for 4' advance and retard. It is difficult, if not impossible to put a vernier adjustment on th crank due to space limitations.

While the Crower 229 is a wonderful camshaft, extensive modeling using Desktop Dyno has shown that the 230 is without doubt the best performing cam in these trucks, all other things remaining equal. Mark and I have discussed camshaft selection at length and he was pleased to hear from me that I had run every cam profile for which I could find data online. I was kinda surprised that some of the more radical cams didn't produce more power or torque, but if you're gonna run a simulation, you ought to believe what it says, if you've put the info in correctly.

k. i went with the 229 cause i didnt want to cut the guides in the heads. trying to save a little as this is a budget regulated rebuild. figured it was better to spend the monnies on rings and arp rod bolts.

 

[ptschram]

k. i went with the 229 cause i didnt want to cut the guides in the heads. trying to save a little as this is a budget regulated rebuild. figured it was better to spend the monnies on rings and arp rod bolts.

AFI and I have put many 230s into unmodified cylinder heads and have yet to encounter a problem with valve guide interference.

Budget builds do not use ARP products. FWIW, rod bolts were the one thing I did NOT replace with ARP when I put my 4.2 short-block together, in spite of it NOT being a low budget build-up.

It looks like my heads are gonna go on a client's truck next week, as a result, I'm thinking it might be time to try my hand at some port-matching.

 

[rover4x4]

How would the head be modified to accomadate the 230? I am guessing you always replace the springs/pushrods/tappets when you do a new cam? What are the specs on the 230?

 

[AfiRover]

How would the head be modified to accomadate the 230? I am guessing you always replace the springs/pushrods/tappets when you do a new cam? What are the specs on the 230?

Some seem to think that the valve guides should be relieved to ensure the retainer does not strike the guide.

I've not needed to replace springs, nor pushrods, but tappets are required every time you swap a cam. As cam replacement has always been part of a headjob, I've had the heads to the machine shop and the springs tested. So far, I've never had to replace springs as my machinist has said he's amazed at how consistent Rover springs are.

Cheers,
PT

(yes, I know, I'm on his shop computer)

 

[ratboy]

AFI and I have put many 230s into unmodified cylinder heads and have yet to encounter a problem with valve guide interference.

Budget builds do not use ARP products. FWIW, rod bolts were the one thing I did NOT replace with ARP when I put my 4.2 short-block together, in spite of it NOT being a low budget build-up.

the specs for my rod bolts say torque to x foot pounds then another 80 degrees. i thought that meant they were torque to yield bolts and should be replaced. the head bolts are, are they not?

 

[ptschram]

the specs for my rod bolts say torque to x foot pounds then another 80 degrees. i thought that meant they were torque to yield bolts and should be replaced. the head bolts are, are they not?

To be honest, if one really wanted to be as anal as i'm often accused of, they would use rod bolt elongation as an indicator of tightness, rather than torque and further angular tightening.

The engine I've been building (for way too f#$%^&* long) is a 4.2 and may well be significantly different than a 4.0/4.6 due to the many changes in the later blocks/engines.

(you do know that you've just forced me to go look that up, don't you?)

 

[ratboy]

To be honest, if one really wanted to be as anal as i'm often accused of, they would use rod bolt elongation as an indicator of tightness, rather than torque and further angular tightening.

The engine I've been building (for way too f#$%^&* long) is a 4.2 and may well be significantly different than a 4.0/4.6 due to the many changes in the later blocks/engines.

(you do know that you've just forced me to go look that up, don't you?)

:rofl:

are they torque to yield? you did look it up, right?

 

[ptschram]

:rofl:

are they torque to yield? you did look it up, right?

Damn you! (head hung in shame) No, not yet, but I did almost get the engine finished I'm putting back together (it HAS to be done tomorrow no later than end of business).

Excuse me, I'm off ot look it up.

PT

ps-now that I think of it, there are differences in the rod bolts from the small journal engines compared to the large journal engines...

 

[ptschram]

Yup! there were two variations as I'd suspected! If the connecting rod has studs and nuts, it's a straight torque spec. If bolts, torque and angle tightening, but I found yet another error in the manual. If you look at the overhaul manual, it goes into great detail on installing the pistons, compressing rings, etc. It then says to fit the bearings and install the heads, nothing about torquing the rod bolts!

And, to further prove just how anal I am, I looked up the inspection procedure for the connecting rods. Nothing about the bolts.

Replacing them could not be seen as a bad thing, but it isn't addressed by Land Rover-curious.

 

[ratboy]

did we ever figure out the solution for this? arp only sells bolts for the early rods not the late ones. my regular supplier dosnt list them. i hate going to the dealer. i really dont need this motor coming apart three hours from home while in the woods with no cell signal and i dont want to buy new bolts if i dont have to. my paranoia may make me do it tho.

 

[robertf]

I reused rod bolts on my 4.0. Iit was a new shortblock that the retards in Oklahoma that I bought it from used cosmoline instead of assembly lube. Nothing has exploded yet.

A friend of mine advanced a 230 a few degrees in his 4.2 using I think the edelbrock timing set with the 3 possible settings. It ran like dogshit until he put it back to the stock keyway.

The retainer takes 5 minutes to cut on a lathe. IIRC the taper was 60* for the centers.

 

[ratboy]

I reused rod bolts on my 4.0. Iit was a new shortblock that the retards in Oklahoma that I bought it from used cosmoline instead of assembly lube. Nothing has exploded yet.

A friend of mine advanced a 230 a few degrees in his 4.2 using I think the edelbrock timing set with the 3 possible settings. It ran like dogshit until he put it back to the stock keyway.

The retainer takes 5 minutes to cut on a lathe. IIRC the taper was 60* for the centers.

i like these answers. i think i will replace my bolts out of paranoia anyway.

 

[ptschram]

i like these answers. i think i will replace my bolts out of paranoia anyway.

Due to te amount of engine work I've been doing lately, the topic of reusing rod bolts came up. No one I've spoken with has had one break or otherwise fail.

Given the relatively low price of the rod bolts, and the high cost if they should fail, I'd replace them if they are torque to yield fasteners.