JF WS6

Anybody successfully running like Harland Sharp, Yella Terra or other aftermarket non-adjustable rockers with Comp R's?? I'm just wondering if this can be done. I want to buy Comp R's but I don't want the expense of the shaft mounted adjustable rockers..... would this be too hard to set up? TIA

BOO HOO BRIAN

iTrader: (-10)

You will need diffrent pushrods since the lash on the lifters is diffrent. Some yella terras are adjustable by using shims under the pads.

JF WS6

Would it be reasonably safe to say that either a 7.35 or 7.4 pushrod would work? Comp R's like less preload than the stockers correct?

LS1_Cruz

ttt. I was going to ask the same question. Thanks.

JF WS6

I have LS6 heads milled .015, custom 230+ comp cam and I will be using the HS rockers.... currently I have Manley 7.4 prods, I guess I'm wondering if I can get Comp R's to work with my current prods or if I need some 7.35's.....

I know it won't be PERFECT because of the non-adjustability, but I figure I should be able to get close..... hopefully.

KRAZY K 2000 TA

iTrader: (5)

I didnt know u could not use them with the stock rockers.I have them on my current combo with a comp custom XE-R cam 236/236 @.050,and .589/.589. also have 8000+ miles

1QUIKWS6

iTrader: (61)

From what I understand - there are a few that have already installed the HS rokers with the Comp 'R's with no problems & needed no shims with std 7.4 pushrods.

Shims can be used if necessary under the HS rockers just like the YT's. I will be using PP 5.3L Stg2 heads with HS rockers, Comp 'R' lifters, 7.4 Manley PR's and a LPE GT2-3 cam. Of course, I'm having Mike @ RapidMotorsports work on my car - so if he can't do it, no one can!

JF WS6

If this is true, then I may just go ahead and give it a shot then. Thanks!

Country Boy

iTrader: (24)

Can you run the Comp Rs with the 7.4 pushrods, yes, BUT you may/ will damage the lifter and it will be noisy as hell. I did it for ~2500 miles. You need adjustable valvetrain or shims to get the preload to .002-.004. They have a preload spec for a reason. You wouldnt torque your lugnuts to 200 ft lbs, would you?

JF WS6

Well, even with the non adjustables there has to be a way to get near to the desired preload with either different length prods or shims somehow...

How much preload does a stock rocker have on Comp R's torqued to the standard 22ft/lbs. with a 7.4 prod (assuming an average aftermarket cam with a smaller base circle)? If that is too much then I may need to go to 7.35's.... I just want to get it somewhere close so I don't do any damage like you mentioned.

BOO HOO BRIAN

iTrader: (-10)

The comp R lifter only wants a zero to ten preload. Around 70 percent of the cars will need an adjustable valvetrain. If there is to much preload they will come apart.

Unaffliated Racing

iTrader: (15)

the Comp R's only require .002"-.004" preload..like counrty said they could be damaged with anymore than that..if you change pushrod length, that will in turn change your valvetrain geometry for the worse..it would be better to shim than change pushrod length

JF WS6

Why is shimming better? To me, shimming changes the valvetrain geometry as well by lifting the rockers up. Going to a slightly shorter pushrod would put less pressure or preload on the lifter to keep it within the acceptable preload range would it not? Why is that not good?

Any guys running the HS rockers and Comp R's measure their preload with no shims and 7.4 prods?

Steve Burger

iTrader: (33)

I will be doing the HS rockers as soon as Nate gets them in. He assured me that this can be done and will be doing the installation. I will post the results on this once the install is done. This seems to be a big topic lately and I want to get this right as well .

I hope this is a good soluition for the Comp R setup.

Unaffliated Racing

iTrader: (15)

Doing the HS rockers will be exactly the same as the stock rockers...since they are non adjustable..you wil be putting between .030"-.050" preload on the Comp R lifters..so if you went to a shorter pushrod (7.35") you would have none..or even less than none preload..thats why it would be better to shim..most rods only come in .050" increments

JF WS6

Ok..... that makes sense. So one size down from the 7.4's is too much. Well, I guess the only way to do it would be shims then like you said. I don't think HS sends shims with their rocker set either.....

Guess I'll have to buy some washers from Home Depot.....

JF WS6

Hmmm...... well if what Spectacle Solutions says is correct, if you used the HS rockers with Comp R's and 7.4 p-rods you'd definately have too much preload at .030"-.050". In that case you would have to shim to get within an acceptable range.

BOO HOO BRIAN

iTrader: (-10)

Any more than 0 to 10 preload and you will be picking up lifter parts out of your engine. The cup that the pushrod rides in is pressed in and not retained by a c clip. Once that is moved out of place with too much preload it cannot hold the internals in.

For less preload you have to do one of two things: shim the rocker to move the pushrod out of the lifter, or get shorter pushrods.

JF WS6

Spectacle Solutions was saying that the next size shorter off the shelf pushrod (7.35) is too short and would cause zero preload or slack even....

I guess I could get a set of custom p-rods, but shimming sounds easier than that.

Nasty N8

iTrader: (33)

I have set them up with Comp R lifters many times with no issues. It is a little trickier to get it just right but can be done.

Nate