anyone use a comp roller cam and lifters in LA small block

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WildCat

WildCat

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I have tried to get info on the roller lifters from Comp Cams and they have not sent or told me anything.

My ? is What mods have to be done to the block to install roller lifters in a 1971 340 block?

I have been told they have some direct replacement lifters for this from a friend. I have heard the lifter bores would need to be bushed to install them form others

Does anyone here have any experience in installing them in an older small block not designed for roller lifters?
 
The old rollers needed bushed bores to restrict the oil. The new retrofit rollers have a different body design that prevents the oil hole from becoming uncovered.
 
What about the new Comp line of Thumpr cams, that have good sound, but are designed not to give away power for the sound? What does everyone think of those and do you have any experience with them? These are roller design if I remember correctly, so what is needed to make them work?
 
What about the Crane hydraulic roller lifters? Do I need to get the lifter bores bushed? They seem a bit loose and I'm getting ready to send the block to the machine shop.:read2:
 
Are you asking about solid or hydraulic rollers.

Shouldn't need to bush with the new hydraulic rollers unless something is seriously out of whack. The lifter bodies are tall enough to shroud the oil holes through full lift on most cams. There's another trick or two to avoid requiring bushing the lifter bores/unshrouding.

As far as direct drop in. No way in hell were the comp hyd. rollers going to fit in my 360 roller block. The valley needed to be ground to clear the tie bar on the "Drop in Retro-fit Rollers". Of course the short block was already put together. Disassembly to grind, rewash and re-assemble was out of the question for me when alternatives were available. I ended up getting the stock MP rollers, spiders and dogbones.
 
crackedback said:
Are you asking about solid or hydraulic rollers.
As far as direct drop in. No way in hell were the comp hyd. rollers going to fit in my 360 roller block. The valley needed to be ground to clear the tie bar on the "Drop in Retro-fit Rollers". Of course the short block was already put together. Disassembly to grind, rewash and re-assemble was out of the question for me when alternatives were available. I ended up getting the stock MP rollers, spiders and dogbones.
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How is that setup working. I'm in the process of assembling a factory roller block with a Comp XE hydraulic roller (280HR or 286HR) and I'm going to be using the factory lifters and retaining hardware. I have been told that I can expect to have issues between 5 and 6,000 rpm, as the stock goodies weren't intended to rev that high. I'm stubborn enough to have to see it for myself though. What about pushrod length, are the stocker gonna work?
 
65deuce said:
I have been told that I can expect to have issues between 5 and 6,000 rpm, as the stock goodies weren't intended to rev that high.
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I haven't put a hotter cam in any of my stock roller motors yet, but as a general rule if a motor has trouble running up higher rpm numbers it is because it lacks the proper amount of valve spring. The stock lifters are pretty heavy so it may take a higher spring rate to get the valves back on their seats.


Chuck
 
I am using the factory roller setup with the 280HR comp retro fit hyd roller cam. The engine it is and I'm finishing the project now so I havent' run it yet. I have heard about issues with the mopar roller lifters at high rpm but not sure I understand the reasoning. Don't the Mopar crate motors use a magnum block and stock roller lifter/dogbone setup? I haven't heard of the crate engines having issue over 6000.

It must like 340 Mopar said and the issue is with weak valve springs.

Steve
 
Does anyone know if the Comp Cams Retro-fit Roller Lifters are lighter then the stock mopar roller lifters? Just wondering if an engine will rev cleanly to 6,000 rpms with those lifters.

Also, is a bronze distributor/oil pump gear needed with the Comp Roller cams?
 
340sFastback said:
Does anyone know if the Comp Cams Retro-fit Roller Lifters are lighter then the stock mopar roller lifters? Just wondering if an engine will rev cleanly to 6,000 rpms with those lifters.

Also, is a bronze distributor/oil pump gear needed with the Comp Roller cams?
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Don't know about the RPM range but I do know that one of the members here works for a Mopar dealer (Mopar Super Center?) & they had the Comp Retro-fit roller lifters listed for almost $100 less than Summit. Also, I have a Comp roller cam. I called them & they told me that I didn't need a bronze gear with it. I'm still a little leery of that info & plan to double (maybe triple) check with them before I assemble my engine.
 
I have decided to go with a solid cam/lifters

Already have adjustable rockers so for the few times the valves will need adjusted will be no big deal, I think I remember how................LOL
 
'64 Cuda said:
Don't know about the RPM range but I do know that one of the members here works for a Mopar dealer (Mopar Super Center?) & they had the Comp Retro-fit roller lifters listed for almost $100 less than Summit. Also, I have a Comp roller cam. I called them & they told me that I didn't need a bronze gear with it. I'm still a little leery of that info & plan to double (maybe triple) check with them before I assemble my engine.
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I saw Hughes Engines has retrofit hydraulic roller lifters about $50 cheaper then Summit:

http://www.hughesengines.com/partDetail.asp?partID=11270

I don't know if these are the Comp Cams units or not?

My machine shop guy says Summit is known for those tactics. Give a good price on the cam and then price up all the parts needed to make it work.

For the Xtreme Energy Retrofit Roller cams Com Cams web site says they will rev anywhere from 5500 to 6400 depending on the profile selected:

http://www.compcams.com/technical/Catalogs/106-07/26-37_228-229.pdf

Can anyone explain this bronze gear thing for roller cams? Why do some roller cams need a bronze distributor/oil pump drive gear?
 
I was told that the comp cams with a part number ending in a 9 are billet steel and require a bronze distributor gear. As far as I could find MP is the only bronze dist gear for a small block out there and guess what its expensive. Like $120.
 
Anyone running a stiff single valve springs for their retrofit Hydraulic roller cam. I have the smallest comp cam hydraulic roller cam 268HR. I have a 1971 340, stock heads and don't want to the machine shop to have my guides cut down to run double valve springs. Is there anyway around this? any help is much appreciated.
 
I am running a Comp Cam roller cam in a 76 LA 360 with EQ magnum heads. I used the Huges retrofit roller lifters:
rollerlifter01.jpg

pushrod%252520angle.jpg


The Comp Cam was a custom hydraulic roller with the fuel pump concentric on the front. 224/230 110LSA .513" lift I/E
 
Thanks, I wish I had a 360 with the magnum heads but I got the 340 with the stock LA heads that only allow a certain size valve spring height. Hoping anyone out there is running a retro fit hydraulic cam on LA heads to find out what kind of valve springs their running.
 
340sFastback said:
Can anyone explain this bronze gear thing for roller cams? Why do some roller cams need a bronze distributor/oil pump drive gear?
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If it is a cast iron cam, the stock distributor gear is fine. If the cam is made from billet steel, you'll need the aluminum-bronze gear. You'll have to ask the cam manufacturer what their cams are made of. If you already have your cam, the billet one is the one that is 100% machined, while cast cams will have rough/cast un-machined areas in between the lobes.

One other potential problem with LA motors with roller lifters is that often the pushrod holes in the heads need to be ground oblong to keep the more severely angled pushrods from rubbing.
 
Yea, old thread with good new info.

srunge55 said:
I was told that the comp cams with a part number ending in a 9 are billet steel and require a bronze distributor gear. As far as I could find MP is the only bronze dist gear for a small block out there and guess what its expensive. Like $120.
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Crane makes a gear (also sold by Hughes engines) that takes the place of the old gear that is compatible with any cam. See Hughes engines for info on it.
 
WildCat said:
I have tried to get info on the roller lifters from Comp Cams and they have not sent or told me anything.

My ? is What mods have to be done to the block to install roller lifters in a 1971 340 block?

I have been told they have some direct replacement lifters for this from a friend. I have heard the lifter bores would need to be bushed to install them form others

Does anyone here have any experience in installing them in an older small block not designed for roller lifters?
Click to expand...

We installed the Comp Cams solid roller lifters in a 340 block and needed some grinding on the block to clear the lifters and that was all. But MRL Performance sell solid rollers that will drop in with no grinding to the block and have pressure oiling to the roller bearings.
 
I heard of MRL and their drop in lifters for Mopars. At the moment, I have both the comp cam retro hydraulic cam xr268hr and matching lifters. They recommend a double spring of their but the Install height is 1.800 in. My LA heads have an install height of only 1.650 in.
Should I run a Mopar double spring that can handle the cams 535 lift? Is it safe? It is made by Mopar with the correct installed height for LA smallblock heads.
 
68fsh said:
I heard of MRL and their drop in lifters for Mopars. At the moment, I have both the comp cam retro hydraulic cam xr268hr and matching lifters. They recommend a double spring of their but the Install height is 1.800 in. My LA heads have an install height of only 1.650 in.
Should I run a Mopar double spring that can handle the cams 535 lift? Is it safe? It is made by Mopar with the correct installed height for LA smallblock heads.
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All dual valve springs require the spring base to be cut, which you said you don't want to do. Another alternative is to use Beehive springs. They use an ovate wire that delivers the pressure needed for your mild hyd roller cam yet their a single spring. Another plus is their lighter so they let the engine rev better. Their a little more pricey and require specific retainers but their an easy drop in solution to no machining. Call Comp cams and tell them what cam you have and the installed ht your working with and your wanting a beehive spring and they should be able to set you up.
 
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