Roller Rocker Ratios

[barrok69]

What is the biggest roller rocker ratio that can fit on a Gen3 set of 3400 heads without Major modifications required?

1.62:1 , 1.65:1... 1.7:1 ??1.8:1 ????

Thx.
~Rob

[bszopi]

The only thing out there that we have found to actually fit it 1.6. No one has taken the plunge to try anything larger, mainly for $$ reasons. There are several 1.65 and 1.7s out there that "might" work, but at ~$500 a set, its a risky venture. The clearancing shouldn't be a problem, its bolting them to the heads and maintaining proper geometry that would be the biggest issue.

[smilinguy99]

The only thing out there that we have found to actually fit it 1.6. No one has taken the plunge to try anything larger, mainly for $$ reasons. There are several 1.65 and 1.7s out there that "might" work, but at ~$500 a set, its a risky venture. The clearancing shouldn't be a problem, its bolting them to the heads and maintaining proper geometry that would be the biggest issue.

Here's a way to reduce the risk: You don't have ot buy whole sets of rockers to see if they work, you can buy them one at a time. I've done that with lots of parts that normally only seem to come in sets. Crane does it, Harland Sharp does it. Lots of companies will do this. It's not completely without risk though, it will cost you about $30-$40 per rocker.

[SappySE107]

yup, been there done that. Hard to sell a single rocker on ebay though when they dont work.

[FastGT31]

harland sharps 1.65 should work since they are a narrow body rocker. summit has a set of 16 for $215.95, part number csp-s1003. i am going to use these when i do my top end swap

[geoffinbc]

HS rockers will work. They meet all the specifications for a SBC narrow body rocker. But the only issue is with lower intake manifold and valve cover clearance. Crane rockers fit the valve covers but not the LIM. Also you may need to file the guide plates for pushrod clearance. But not a big issue.

[Syn]

just go with a better cam

[torq455]

just go with a better cam

but that's more expensive and more work.

[Syn]

but going with prolly what custom rods and haven to measure them and ect it becomes a good amount of work too

just yankin your chain. curious on what someone is gonna try

but still upping the ratio won't you have to worry about the springs or no?

[barrok69]

im building a complete engine russ.

i got LS2 springs sitting in my basement, cam is still undecided... and pistons... forged 9.0:1 Wiseco's etc etc..

was looking at the HS 1.65's a while back but never knew if they'd fit properly.

i'll probly just buy them and give'em a whirl.

[torq455]

why not just go with what you know will work with 1.6, and just get a cam with the lift you are looking for? Russ, i didn't have to measure my p-rods for a different rocker ratio. they are just fine.

[Syn]

dang rob u never told me, def good news to hear

going boost as well?

[barrok69]

dang rob u never told me, def good news to hear

going boost as well?

yeah i'm building a "built" & boosted 3400 on the side.... that way i can still daily drive my current 3400 z24

[Syn]

sweet man i've been to windsor a few times and u never answer my pm's whats with that

hec from v6 wants to come out

[barrok69]

harland sharps 1.65 should work since they are a narrow body rocker. summit has a set of 16 for $215.95, part number csp-s1003. i am going to use these when i do my top end swap

I have a 2003 3400, should I be looking at rockers with 3/8"s studs or 7/16"s ??

the S1003's have 3/8" stud, whereas the S1006's are 7/16" stud.


....need help....