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  #1  
Old July 9th, 2007, 15:19
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killer98xjsport killer98xjsport is offline
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roller rockers

I am installing a new 4.0l this weekend and I want to know if anyone has installed roller rockers. Is it worth the $340.00
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  #2  
Old July 9th, 2007, 16:11
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Re: roller rockers

I'm curious about that myself. Anyone? Beuller?
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  #3  
Old July 9th, 2007, 16:53
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Re: roller rockers

i have built quite a few chevy motors and the rollers make a big difference. much less friction being on of the biggest gains. but i really dont know of anyone that has done that on a 4.0L, or on an off road machine. i would like to know what the "bennies" are as well. i would love to do it on mine.
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  #4  
Old July 9th, 2007, 17:43
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nosigma nosigma is offline
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Re: roller rockers

I have them on my 4.0

cylinder head that is heavily ported with 3 side draft webers and a big cam sitting in my 1966 Rambler convertible. I run that motor up to 5750 rpm all the time.

Personally I wouldnt bother with it on an offroad engine that sees low RPM. Its not like I need the reliability or the extra hp in the rocks. Put the money towards gears if you need them, you will get more pulling power for the money spent.

John
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  #5  
Old July 9th, 2007, 18:40
MrShoeBoy MrShoeBoy is offline
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Re: roller rockers

I have roller rockers on my 4.6L stroker motor. I have built several other motors with out roller rockers including my old stroker and I HIGHLY recomend them. If you run any type of cam thats bigger than factory the factory rockers dont like it and will show some wear with in 60k miles. Plus the factory stamped rockers make all sorts of noise with a higher lift cam. I now run a Hesco cam with roller rockers, its so much more quiet than my old motor with a crane cam and factory rockers, and the Hesco cam is much more agressive than the crane.

AARON
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  #6  
Old July 10th, 2007, 10:56
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Re: roller rockers

Quote:
Originally Posted by nosigma
I have them on my 4.0

cylinder head that is heavily ported with 3 side draft webers and a big cam sitting in my 1966 Rambler convertible. I run that motor up to 5750 rpm all the time.

Personally I wouldnt bother with it on an offroad engine that sees low RPM. Its not like I need the reliability or the extra hp in the rocks. Put the money towards gears if you need them, you will get more pulling power for the money spent.

John
X2 your $ would be better spent elsewhere.
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  #7  
Old July 10th, 2007, 11:35
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Re: roller rockers

honestly, i dont really think roller rockers would have much of an impact on a non-high-performance motor. on a stroker that will see higher rpms and a greater amount of power/work, id say go for it. but a stock 4.0, i doubt you'd notice anything

i agree, spend the dollar signs somewhere else [perhaps first stroke it, THEN use the roller rockers]
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  #8  
Old July 10th, 2007, 13:31
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terryd terryd is offline
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Re: roller rockers

roller rockers reduce friction on the top end, reduce load on liftes (easier to "rock") and produce lower oil temperatures. i dont see a down side? h/p gains are minimal, but with the other benifits they are a good addition to any engine. you could drop the $$ else where, true. $340 is a locker, two tires, SYE kit, or any number of other things...... how do you drive it?
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  #9  
Old July 10th, 2007, 17:09
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Re: roller rockers

Quote:
Originally Posted by MrShoeBoy
I have roller rockers on my 4.6L stroker motor. I have built several other motors with out roller rockers including my old stroker and I HIGHLY recomend them. If you run any type of cam thats bigger than factory the factory rockers dont like it and will show some wear with in 60k miles. Plus the factory stamped rockers make all sorts of noise with a higher lift cam. I now run a Hesco cam with roller rockers, its so much more quiet than my old motor with a crane cam and factory rockers, and the Hesco cam is much more agressive than the crane.

AARON
I don't see how they could make less noise than stock. My stroker has 22K on it now, it was built reusing all my stock valvetrain which now currently has 211K on it. I use a crane cam(I know I am nervous lol) and the ONLY thing you can hear on my motor when its idling is the injectors ticking. I drive it like I am trying to outrun the rear bumper as well lol.

I have a set of erson shaft mounts for my other car so I know all the reasoning behind them I just don't see how they could make less noise than something that doesn't make any noise lol.
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  #10  
Old July 10th, 2007, 17:47
MrShoeBoy MrShoeBoy is offline
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Re: roller rockers

Quote:
Originally Posted by rocklandxjer
honestly, i dont really think roller rockers would have much of an impact on a non-high-performance motor. on a stroker that will see higher rpms and a greater amount of power/work, id say go for it. but a stock 4.0, i doubt you'd notice anything

i agree, spend the dollar signs somewhere else [perhaps first stroke it, THEN use the roller rockers]

Stroker motors see the same RPMs as the regular 4.0L motors. Just about everybody with a stroker motor in a Jeep is still using the factory ECU to run it and the rev limiter is still set at 5250rpm (HO motors). Reving the 4.0L regardless if its stroked or not past 5500rpm will blow it up. Cam harmonics will bust the timing chain.

Cuda, I always noticed a lot of valvetrain noise with my stroker with the factory rockers. When the roller rockers went on, that noise went away... Maybe the motor I had was just special?

AARON
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  #11  
Old July 10th, 2007, 20:32
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Re: roller rockers

Quote:
Originally Posted by MrShoeBoy
Stroker motors see the same RPMs as the regular 4.0L motors. Just about everybody with a stroker motor in a Jeep is still using the factory ECU to run it and the rev limiter is still set at 5250rpm (HO motors). Reving the 4.0L regardless if its stroked or not past 5500rpm will blow it up. Cam harmonics will bust the timing chain.

Cuda, I always noticed a lot of valvetrain noise with my stroker with the factory rockers. When the roller rockers went on, that noise went away... Maybe the motor I had was just special?

AARON
true, however...

stroker drivers frequently take their motors on more ... spirited ... drives than those of us with stockers.
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  #12  
Old July 10th, 2007, 20:37
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Re: roller rockers

Quote:
Originally Posted by MrShoeBoy
Stroker motors see the same RPMs as the regular 4.0L motors. Just about everybody with a stroker motor in a Jeep is still using the factory ECU to run it and the rev limiter is still set at 5250rpm (HO motors). Reving the 4.0L regardless if its stroked or not past 5500rpm will blow it up. Cam harmonics will bust the timing chain.

Cuda, I always noticed a lot of valvetrain noise with my stroker with the factory rockers. When the roller rockers went on, that noise went away... Maybe the motor I had was just special?

AARON
At least one of ours is special lol.
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  #13  
Old July 10th, 2007, 22:27
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5-90 5-90 is offline
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Re: roller rockers

Roller rockers are something usually done to complement other modifications.

If you're looking for more power, there are other places to look (boring/stroking being a great place to start. A cam swap is second best - but would also complement a bore/stroke job.)

If you're trying to wring every last little bit of power out of your engine, roller rockers will help to reduce parasitic drag losses in the valvetrain. However, you'll still have the huge parasitic frictional drag caused by the sliding contact between the lifter foot and the cam lobe - and, to date, there's nothing we can do about that (although there is discussion afoot on strokers - groups.yahoo.com/group/strokers.) The advantage to running roller-foot lifters would not only be a reduction in parasitic drag (caused by the significant reduction in friction,) but it would allow steeper valve ramps and the running of more aggressive cam lobe profiles - part of the reason, I'm sure, that OEMs have gone to roller lifters in the first place (it would also help address the issue we're having with engine oil. Roller-foot lifters would reduce friction between the cam lobe and the lifter by a couple orders of magnitude (in addition to allowing more aggressive camshaft profiles,) but they must be run with a "roller" cam - you can't run roller lifters with a flat lifter cam.

For maximum-effort engines, the "best" rocker would have a pivoting socket for the pushrod and a roller "toe" for contact with the valve tip, which would reduce friction in both spots. However, you don't see those anywhere, really. Putting the "roller toe" in is a positive step, however - that also reduces friction by an order of magnitude or two. (Seriously - it's that great a difference.)

However, taken as a percentage of the whole, you're not losing much in the upper valvetrain due to parasitic drag. You're going to lose most of your power at the lifter feet and in the friction between the piston rings and the cylinder bores, with the second-place winner being pumping losses (and there's not much you can do about the ring contact area and the pumping losses - although I've heard very good things about barrel-faced molybdenum-coated piston rings...)

Would I install rollerised rocker arms on their own? Not worth the money. As part of a comprehensive engine modification package? Certainly - because it would complement other modifications.
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