LS1 and 1.85 rocker arms?

**GMCAMARO** · 01-04-2009, 02:07 PM

I have a question. I am considering going to 1.85 ratio rocker arms.

Currently, I have Comp Cams valve springs, do these need to change? They have a spring rate of 441 lbs/in.

My cam dimensions are as follows.

Intake Exhaust

Intake Gross valve Lift .525 .532
Lobe lift .3090 .3130

Will these springs work and will the valve cover require modifications?

**9t8z28** · 01-04-2009, 04:01 PM

What rockers are they?

**squee** · 01-04-2009, 05:39 PM

I wouldn't go with 1.85 rockers. If anything, I'd get Crane quick-lift rockers. The geometry is different.

**GMCAMARO** · 01-06-2009, 01:50 PM

Originally Posted by 9t8z28

What rockers are they?

Okay, I am sort of changing my mind.

I am thinking about going with the Crane Cams, Gold Race Extruded Aluminum Roller Rocker Arms for LS1/LS6 in 1.7 Ratio.

My concern is why do I have to concern myself with lifter bleed down. Just trying to understand why the bleeding is necessary. I read SLPs instructions yes I know they suck but they do not concern themselves with bleeding.

Just trying to understand why I do with the crane Rocker arms?

**Bouvers** · 01-06-2009, 02:52 PM

what else are you doing with the rocker arm change?

**GMCAMARO** · 01-07-2009, 04:26 AM

Originally Posted by Bouvers

what else are you doing with the rocker arm change?

While here pushrods also.

Any other ideas?

**nhraformula** · 01-07-2009, 07:37 AM

Originally Posted by GMCAMARO

While here pushrods also.

Any other ideas?

use an ls6 spring

**GMCAMARO** · 01-07-2009, 09:40 AM

Originally Posted by nhraformula

use an ls6 spring

Already have Comp Cams -18

**9t8z28** · 01-07-2009, 11:19 AM

Originally Posted by GMCAMARO

Okay, I am sort of changing my mind.

I am thinking about going with the Crane Cams, Gold Race Extruded Aluminum Roller Rocker Arms for LS1/LS6 in 1.7 Ratio.

My concern is why do I have to concern myself with lifter bleed down. Just trying to understand why the bleeding is necessary. I read SLPs instructions yes I know they suck but they do not concern themselves with bleeding.

Just trying to understand why I do with the crane Rocker arms?

The SLP rockers are actually pretty good. The Crane rockers are a little expensive but definitly good quaility. I would recommend the Harland Sharp rockers or the Yella Terra which are around $350-$400

What do the instructions state to do?

**nhraformula** · 01-07-2009, 12:07 PM

Originally Posted by 9t8z28

The SLP rockers are actually pretty good. The Crane rockers are a little expensive but definitly good quaility. I would recommend the Harland Sharp rockers or the Yella Terra which are around $350-$400

What do the instructions state to do?

The SLP rockers arent bad, i gained 9 rwhp and 17 lbs of tq when i had them put on. The problem with 1.85 rockers is that they limit your cam selection.
if you google nhraformula 1.85 rocker arms, you find my graph from the dyno.

**GMCAMARO** · 01-07-2009, 12:07 PM

Originally Posted by 9t8z28

The SLP rockers are actually pretty good. The Crane rockers are a little expensive but definitly good quaility. I would recommend the Harland Sharp rockers or the Yella Terra which are around $350-$400

What do the instructions state to do?

Which instructions?

The SLP one's just say unbolt them, put them in, torque them and way you go. The Cranes say bleed hydraulics.

**mrr23** · 01-14-2009, 11:33 AM

Originally Posted by GMCAMARO

Which instructions?

The SLP one's just say unbolt them, put them in, torque them and way you go. The Cranes say bleed hydraulics.

SLP rockers are just like stock style. non adjustable. the crane are fully adjustable. so you need to set correct lifter preload. ran them on both of my cars. got a solid 17 rwhp gain using the 1.8 rockers.

here is how you adjust them
http://vincihighperformance.com/LS1%...TRUCTIONS.HTML