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Mar 1, 2010 | 10:38 PM

88yellowvette

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Rocker arms

Is it worth changing out the stock rocker arms to after market ones?

Thanks,

Mar 1, 2010 | 11:45 PM

John A. Marker

Le Mans Master

Joined: Mar 2004

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From: Dublin CA

Are you doing the work yourself...if so then the cost would be reasonable. The formed steel rockers are supposed to be a 1.5 ratio but they range from 1.4 to 1.5. They also generate more heat since they are riding on a smooth surface whereas roller rockers have bearings.

If you change to roller rockers going to a 1.6 ratio you will probably gain 10-15 hp. That is not to noticeable...but it all adds up. Your engine oil temp. will also run about 5-10 degrees cooler.

.

Mar 2, 2010 | 12:19 AM

Pwnage1337

Tech Contributor

Joined: Oct 2008

Posts: 3,729

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From: Custer, WI

this is one of the most common mods suggested. you can pick up a full set of summit racing roller rockers for 170 dollars.

Mar 2, 2010 | 01:51 AM

rogerdoger1993

Instructor

Joined: Feb 2009

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From: Woodstock IL

I just ordered a set of these and they should be in by tomorrow. Cant wait to try them out.

http://www.prwonlinestore.com/blumax...kerarms19.aspx

BTW here is a lengthy article that shows proven dyno results of 1.6 full roller rockers.

http://www.vetteweb.com/tech/vemp_07...rms/index.html

Mar 2, 2010 | 06:04 AM

65Z01

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From: SE NY

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Quote:

Is it worth changing out the stock rocker arms to after market ones?

On an '88 you it's easier to go with non self-aligning RRs since you must remove the stock guide plates anyway. Also you should change the springs; the Comp Cams #981 spring works well with stock cam & 1.6:1 RRs. Once you have the springs off it's a good idea to replace the stock valve seals too...see how it "adds up"...

Mar 2, 2010 | 06:57 AM

aboatguy

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Joined: Jan 2005

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From: Slidell Louisiana

Quote:

Originally Posted by 65Z01

you should change the springs.....and if you're in that deep the OH BUY THE WAYS and might as wells start to add up.

Mike

Mar 2, 2010 | 02:15 PM

88yellowvette

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Quote:

Originally Posted by 65Z01

I have a mild cam from comp cams I put in years ago and also changed the springs. The 1.6:1 ratio rockers would still work correct?
I do have to remove the guide plates?
Are the stock push rods ok?

Thanks you and to everyone who is helping out.

Mar 2, 2010 | 02:55 PM

65Z01

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Joined: Dec 2000

Posts: 90,675

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From: SE NY

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Quote:

I have a mild cam from comp cams I put in years ago and also changed the springs. The 1.6:1 ratio rockers would still work correct?
I do have to remove the guide plates?
Are the stock push rods ok?

If you use self-aligning RRs, replace guide plates with spacers and stock PRs are ok. If you use non self-aligning RRs, replace guide plates & PRs with hardened units.

Calculate the total lift with 1.6:1 RRs using that "mild cam" to select the appropraite spring.

When I installed the Comp Cams ProMagnum 1.6:1 RRs I used CC 981 springs. Now that I'm having a CC 08-500-8 cam installed I'm backing down to 1.52:1 ProMagnums and staying with the 981s which are recommended for that cam.