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1.9 modded rocker arms

01GrandPrixTURBOGT

01GrandPrixTURBOGT

New member
Im wanting to get a set of rocker arms and im just wondering what springs and retainers i would need so that i dont have to worry about valve float? Im doing this on my top swapped grand prix by the way.
 


Gotta love the support you get from GPF... I did 1.9 RR's and actually felt a good gain. I did 90# LS6 springs along with locators, beehive spring retainers (Manley), and comp locks. I believe they were installed at 1.720". 115# on the seat 300# open at .488 lift.
 


I know lol if i wanted to know which was better i would of asked but thanks thats what i was looking for i was debating on whether or not to get the 90#s or the 105#s.
 
Sushamouf said:
Gotta love the support you get from GPF...
Click to expand...
Yeah, whole forum sucks because the first two guys didn't answer the question. :confused: Please cut negativity and add the good info you know, instead of adding to the issue.

OP
Personally I wouldn't suggest the LS6 springs as they are tougher on the timing chain and dampner based on their spring rates as they are compressed. 105's or LS9/L76 would be a better choice. Proper install height on any LS based (LS6, L76/LS9, or 105) is expected/suggested to be 1.800". Our heads with stock retainers will yield 1.72x", with modded/Manley retainers you will see 1.78x" which is how 99.9% of people run.

As for rockers. If you don't already have the 1.9's. I'd suggest looking for ER's. They tend to get more performance out of an NA motor than 1.9's.
 
1.72 is asking for trouble with those springs.

.490 max lift is your limit at that height. That's right around what you'll see with 1.9s.

Is bad advice better than no advice?

Calculate spring pressure at your lifts.

Apparently 105s will be lower than ls6s with rockers.

You could also throw some l76 springs in there. Moderate spring rate 90s.

But its not like this hasn't been covered a thousand times.
 
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Actually max lift is .500. They were set up by an engine builder that does heads all day everyday. The guides were machined along with liners and retainer-to-seal clearance was checked along with coil bind. They are perfectly fine, you just need to know what you are doing.
 


Rated max lift is 570 when installed at 1.8.

What sort of magic math do you speak of?

If a pro set them up he would have asked for the recommended install height. Right now your seat pressure is probably way too high meaning you're going to see even more wear than you would normally expect out of ls6's.

You'll see 120 seat, 304 open.
Compared to 98 seat, 282 open.
 
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No, its .580 at 1.800 and therefore .500 at 1.720 and I looked, my install height with the locators was 1.770 not 1.720.

Sent from my Droid
 
BillBoost37 said:
Yeah, whole forum sucks because the first two guys didn't answer the question. :confused: Please cut negativity and add the good info you know, instead of adding to the issue.

OP
Personally I wouldn't suggest the LS6 springs as they are tougher on the timing chain and dampner based on their spring rates as they are compressed. 105's or LS9/L76 would be a better choice. Proper install height on any LS based (LS6, L76/LS9, or 105) is expected/suggested to be 1.800". Our heads with stock retainers will yield 1.72x", with modded/Manley retainers you will see 1.78x" which is how 99.9% of people run.

As for rockers. If you don't already have the 1.9's. I'd suggest looking for ER's. They tend to get more performance out of an NA motor than 1.9's.
Click to expand...
i have a top swap so wouldnt 1.9s be good?
 


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