shotgun_000

Tax refund time is here, and I'm ready to continue my engine project. The next thing I want to add is a good set of roller rockers. I don't mean the cheap roller tips, I'm talking about true rollers.

I'm willing to spend $200-$300 for the rockers.

My only question is which ones to buy. I think I will avoid the 1.6 ratios, and stay with the 1.5's My DD2000 shows that 1.6 rockers provide little or no gain below 5500. My engine redlines at about 6000, so I think it would be useless to go with the 1.6's. Plus, correct me if I'm wrong, but the extra ratio can cause clearance problems, as well as other issues. I think the 1.5's would be easier to install and maintain.

Also, I think true roller rockers are larger in size, so will I have clearance issues? Do I need taller valve covers? The current valve covers I have are from an 87 corvette. The heads I have allow early or late model valve covers, so I went with the centerbolt design to help avoid leaks.

I'm running 3/8 studs on my Pro Action heads, so I know to watch for that when ordering. Anything else I should watch for?

Which rollers would you buy, based on my engine spec (see sig.)

Thanks for your comments or suggestions! :cheers:

Gordonm

You say the cheap roller tips. I'm running them to 7000 rpm with no problems at all. You will gain no noticable HP over the "cheap" roller tips. They both will provide the same amount of lift. you do not need roller rockers unless you spring pressure is over 350 pounds of pressure. Yes a little less friction but nothing noticable. If your heart is set on roller rockers you will need to get a set of higher valve covers. The best in my opinion is Crane Gold roller rockers. Not to many problems with them. Harland Sharp is not as well known but also make some good ones. Either one will work fine. :cheers:

L82-JWS

I have a similar question. I am running with the ZZ4, and was wondering if it would be any value to go with roller rockers? If so, 1.5, 1.6? Any additional mods if I go that route? Thanks! :confused:

garagedweller2

Harland Sharp claim to be the inventor

ED DINAPOLI

I had Crane gold roller rockers for about 10,000 miles. I had one fail last fall. The trunion bearings were the cause of the failure. I checked the alaignment of the failed rocker and everything checked out. I just recently changed to Crowler stainless steel roller rockers. I wanted to keep the roller rockers,as my compressed spring pressure is 450#. I agree with Gordomn on the roller tips . IF you decide to go to 1.6 ratio rockers then I would go with the roller rockers.

shotgun_000

When I say cheap, I don’t mean to imply that roller tips are junk, just that many people think they are they same thing as roller rockers.

I’ve read many articles on roller tips, and many of the articles showed that the roller tip was of no real benefit in reducing friction. There is little movement on the valve tip compared to the pivot point of the rocker itself. On the other hand, the article showed that it didn’t hurt anything either by using roller tips. Roller rockers are where the true friction reduction properties are, which results in more power.

My opinion is just based on these articles, and people I’ve talked with, not necessarily the whole truth to the matter. If I’m wrong, hopefully someone will step in :cheers:

Ganey

Based on your engine specs., you do not need full roller rockers, all you need is Comp Cams roller tip.
Where full rollers are needed, then SS are rec.
Have done many Roller Rockers posts. http://forums.corvetteforum.com/zero...870718#2870718

AlwaysWave

Another budget item. You have to check your rod length also, to insure the tip is centered on the valve stem.

GrandSportC3

I don't think that there's too much difference between brands.. I have used the cheapest Crane Roller Rockers and my current engine has Lunati Roller Rockers... None of them gave me any trouble..

:cheers:

Olivier

79 Midnight Blue L82

I put the Harland Sharp 1.5 rollers on my car last summer. I had a complete tuneup done at the same time the rollers went on so I really cannot vouch for how much improvement the rockers made as the whole engine just run much better after getting everything adjusted as it should be. I did have to go with the taller valve covers to clear the roller rockers. I got the Edelbrock Signature series and they really look nice.

442olds

I put a set of Self Aligning Pro-Form (el-cheapo brand) Full Roller 1.6:1 Rockers from Summit (part #PRO-66915 $179 for all 16 with poly locks) on my 93 Z-28. The clear the stock steel centerbolt valve covers, they are also the narrow body style needed for the centerbolt valve covers as well. So yes they will fit under stock vavle covers if your heads have the raised gasket mounting surface which they will if they are set up for both style valve covers.

Don't always hold the Desk Top Dyno to heart either. A set of full roller rockers at 1.6:1 freeded up a lot of power in my 130,000 mile Z28 over the entire powerband and I shift at 5700 rpms. What you need to do is look at the flow data for your heads and figure out what the maximum lift will be with your cam. If your heads still flow more air above the max lift of the cam you will benifit from having the valves opening the extra distance. The ideal situation is to open the valves as fast as possible to the point where the heads are at max air flow and hold it there as long as possible (cam duration) and then close it as fast as possible but not let the valve bounce off the seat.

So I say go for the 1.6's you won't regret it.

Oh yeah if you do go for the self aligning rockers remember to remove your guideplates if you have guide plates installed.

Tominator

Not to doubt the DD but with your lift of 454/.480 the 1.6 would bump it up which should translate into more ponies. It won't do much for your duration though. I would also think that it would be able to be felt after 2500 RPM.

I would guesstimate that it would get your lift into the .475/.500 range and would be a very nice combo in my opinon.

I went with the Summit 1.6 roller tip rockers and have put about 6000 miles on them and think I really put them to the test.

Maybe some the cam (Ganey and glad your back with us) experts can shed alittle more lite on this subject.


[Modified by Tominator, 12:35 PM 1/29/2003]

Shock

On my last America car project (a 1970 Mustang Mach I with 351C)

That engine was built pretty well. 4V heads, bigger cam etc. And I used the Crower SS roller rockers. On that engine they made 11 more hp over the stockers. The ratio was 1.73 which is stock for the 351C.

That being said, the 4V heads breathe better than any Chevy head aftermarket or not, so that might have made a difference. It was strictly a track engine for road racing, so it was built to see 8000rpm on overrev and shifts at 7400.

Mike the former Ford guy :leaving:

nunus79

Aren't those heads commonly referenced by many technical articles as an example of a head that has great flow numbers but are dissapointing performers because of the large runner sizes? Then those articles go on to say "bigger is not necessarily better, yada, yada, yada". :jester :troll

Glad you've seen the light! :chevy :chevy :chevy

Ryan77

:iagree: :yesnod: :yesnod: :yesnod: :yesnod:

garagedweller2

what's the difference between roller tip and full roller?

page62

The rocking action in the roller tip is just like OEM (i.e., thank god for oil). But the part that strikes the valve has a roller, unlike an OEM rocker which has a flat metal striking surface.

The roller rocker has needle bearings to facilitate the rocking action, plus the roller tip.

garagedweller2

oh, so the roller tip uses a stud as the pivot and the rollers a needle bearing?

spokewrench

Why not use the ones in the G.M. Performance catalog? :chevy :chevy :chevy


[Modified by spokewrench, 7:25 PM 1/30/2003]