Comp gold 1.85 ratio rockers
07-21-2015, 08:49 AM
#3
Team Owner
When you add the rockers, you also need valve springs. Then you should check the wipe pattern which if correction is require, will result in new pushrods. Lot of money for marginal gain for this single modification. There may be better ways to spend the funds.
07-21-2015, 09:37 PM
#4
Pro
Thread Starter
Comp gold 1.85 ratio rockers
I have new springs I was going to put on a set of 243 heads and upgrade from my stock ls1 heads on my 98. So I am pulling it apart anyway. Figured aluminum roller rockers would be better than stockers and the extra ratio would hopefully help.
07-22-2015, 12:01 AM
#5
Melting Slicks
Ease of install , overall cheaper than a cam(associated parts needed that come with installation), and a SOTP difference. I'm doing a very tame build on my Z which will include 1.8 rockers and some PAC valve springs. The LS6 springs are good to .570-580 lift IIRC which if I'm not mistaken will hate 1.8 rockers. Or at least will push it to the brink of valve float.
Good luck with your build and let us know how it goes.
Will you be doing a LS6 IM as well?
07-22-2015, 12:15 AM
#6
Le Mans Master
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St. Jude Donor '13-'14-'15
Yes you must install better valve springs--- I saw an average 18 RWHP gains on the dyno with a stock cam and Yella Terra 1.8's --this was one of my 1st mods before changing the cam--
Depends on the year of your car--An older LS1 with a LS1 intake manifold will show somewhat less results as the intake manifold becomes the chock point--- Hoping that you have an LS6 intake as it will allow you the full 18RWHP gains--- PLUS another 10-12 RWHP over a LS1 intake even with a stock cam !!
Depends on the year of your car--An older LS1 with a LS1 intake manifold will show somewhat less results as the intake manifold becomes the chock point--- Hoping that you have an LS6 intake as it will allow you the full 18RWHP gains--- PLUS another 10-12 RWHP over a LS1 intake even with a stock cam !!
07-22-2015, 12:20 AM
#7
Melting Slicks
Yes you must install better valve springs--- I saw an average 18 RWHP gains on the dyno with a stock cam and Yella Terra 1.8's --this was one of my 1st mods before changing the cam--
Depends on the year of your car--An older LS1 with a LS1 intake manifold will show somewhat less results as the intake manifold becomes the chock point--- Hoping that you have an LS6 intake as it will allow you the full 18RWHP gains--- PLUS another 10-12 RWHP over a LS1 intake even with a stock cam !!
Depends on the year of your car--An older LS1 with a LS1 intake manifold will show somewhat less results as the intake manifold becomes the chock point--- Hoping that you have an LS6 intake as it will allow you the full 18RWHP gains--- PLUS another 10-12 RWHP over a LS1 intake even with a stock cam !!
07-22-2015, 09:50 AM
#8
Pro
Thread Starter
Comp gold 1.85 ratio rockers
Great info tblu92 with the heads and rockers I would be thrilled to pickup 30hp total 20 would even work. I am staying in tt3 group with Nasa so I don't want to make too much power. I just want reliable. Also I do have the ls6 intake.
Thanks everyone
Thanks everyone
07-25-2015, 12:02 AM
#9
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St. Jude Donor '13-'14-'15
If you buy heads that have been shaved to increase the compression ratio is when you generally have to change the pushrod lengths---
I would always check it anyway---It's easy to do
On cylinder 1 --color the top of both valve stems using a sharpie pen
Install one set of the 1.8 pushrods and rockers on that cylinder
Pull the fuse on the fuel pump and crank the engine over without starting for 10-20 seconds
A rocker arm swipe mark will show on top of the valve by wearing off the sharpie color-- You want the swipe mark to be in the CENTER of the valve tip---If it is not---either too close to the center of the engine or too close to the outer side of the engine dictates if you need shorter or longer pushrods--
Last edited by tblu92; 07-25-2015 at 12:16 AM.
07-26-2015, 05:57 PM
#10
Melting Slicks
I measured the valve geometry just to be safe and the STOCK pushrods were within spec with the 1.8's ----If you install different heads (as I did as my next mod) I measured the geometry again to be safe and again it was perfect-- I replaced my stock LS1 heads with stock LS6 heads---
If you buy heads that have been shaved to increase the compression ratio is when you generally have to change the pushrod lengths---
I would always check it anyway---It's easy to do
On cylinder 1 --color the top of both valve stems using a sharpie pen
Install one set of the 1.8 pushrods and rockers on that cylinder
Pull the fuse on the fuel pump and crank the engine over without starting for 10-20 seconds
A rocker arm swipe mark will show on top of the valve by wearing off the sharpie color-- You want the swipe mark to be in the CENTER of the valve tip---If it is not---either too close to the center of the engine or too close to the outer side of the engine dictates if you need shorter or longer pushrods--
If you buy heads that have been shaved to increase the compression ratio is when you generally have to change the pushrod lengths---
I would always check it anyway---It's easy to do
On cylinder 1 --color the top of both valve stems using a sharpie pen
Install one set of the 1.8 pushrods and rockers on that cylinder
Pull the fuse on the fuel pump and crank the engine over without starting for 10-20 seconds
A rocker arm swipe mark will show on top of the valve by wearing off the sharpie color-- You want the swipe mark to be in the CENTER of the valve tip---If it is not---either too close to the center of the engine or too close to the outer side of the engine dictates if you need shorter or longer pushrods--