i blew my head gasket so while the heads were off i decided to do a little clean up and gasket match everything from throttle body to exhaust manifold....i did a 5 angle valve grind and made those huge blobs in the intake ports sharp as razors....will i need the 1.6 ratio sbc rockers to get the full bennifit out of my engine?

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If you are not changing cams then 1.6 rockers will give you a little more lift. This will help your flow since you are port matching things.
Also you don't need to go to SBC rockers, Comp Cams makes a set of 1.52 and a set of 1.6 roller tipped rockers that are bolt-in for the 60* V-6 engines.

http://store.summitracing.c...14%2D12&autoview=sku

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Happiness isn't around the corner...
Happiness IS the corner.
ZZ4 Powered !!

Or even eaisier and WAY cheaper (mabey not eaiser for the auto-impared) go to a junkyard and pick to gm 3100's old 3100 with the fiberglass valve covers...hehe what i did just took a hammer and busted threw 2 valve covers on 2 different 3100 cars and unbolted the rockers and bought them for .50$ apiece..they look like these..


btw....i didnt notice a bit of change when i added them...i too did them with a head gaskett.

[This message has been edited by 88 Silver Formula (edited 04-29-2007).]

if you dont replace the intake or at least get it ported you will see no change above 4000 rpm, where those changes would make a difference.

ALSO, do not just slap in 1.6 rockers. you need different springs on your valves for those rockers. Now, doing this now means that improvement is sitting there waiting until you do upgrade the intake.

At lower RPM's the stock valve restrictions are non existant, it's only higher rpm where that benefit happens.

..you dont need stiffer springs.....i ran stock springs for over a year (running it hard as hell) and no issues..even at 5900 rpms theres no valve rattle...thats one of thoes "well you might want to" deals but its not needed...however it is needed on a 3400 conversion with 1.6's....the springs in that pic are 308lb to match the 3400 thoes heads are going on...

quote Originally posted by 88 Silver Formula: ..you dont need stiffer springs...

Second this.

If you have a stock cam and are adding the 1.6 rockers, the stock springs will work just fine.
I will add that if your springs are old and tired, they possibly should be replaced, anyway.

I used the Comp Cams 1.6 roller tipped rockers. They (combined with an underdrive pulley set) made a noticeable difference on my 3.4.

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Raydar
88 4.9 Formula IMSA Fasback..........................88 3.4 coupe -soon to be something other than red

Read Nealz Nuze! Praise the Lowered!

Just to clarify the last two posts. When I did my 1.6 roller tip rockers, I had my springs rate tested at the machine shop when I got my valves re-seated. Best to check old springs IMHO

Arn

thanks for the help....does it matter what year 3100's? or just any with the fiberglass valve covers?

any with fiberglass vlave covers, if you look at that pic i posted at the rockers, the top of them has a small tab that pertrudes over the pushrod...make sure the ones u get has thoes...thats a sure fire way to tell if you have the right 3100...and you can unbolt the 2 front eng mounts and remove the water line that stretches acrocc the valve cover....but its much eaiser to hammer the death outa them... lol, i dont recall acual makes/yr modles that have these pretty sure its between 91 and 95 gm 3100's not 3.1's...notice how mine are different colors..half dark half light...2 engines lol...its eaiser to hammer the front valve cover on 2 rather than unbolt the back valve cover on the same one..