[staleg]

Hi!
I'm in the process of building a '34 Ford Roadster. It has a L05 Chevy small block 350 engine. Factory roller block, flat top pistions (I've read somewere that L05 engines from 9C1 package cars have flat top pistons, correct me if I'm wrong). It's rebuilt from TBI to carb.

Quick Fuel (Holley based) 650 cfm dobbelpumper carb with annular boosters, PP Crosswind (Air Gap knock off) intake.
Rewarder semi length headers, 2 x 2,5" exhaust.
Transmission is a T-56, 6 speed manual from a 95 LT-1 Camaro. Jaguar IRS rear axle, ratio 4,09:1. Rear tires are 295/50-16.
My plans for the engine is to use it as it is from the start, but later rebuild it with modifed Vortec heads and a suitable cam.

A while ago I came across a pair of nice 906 Vortec heads that I got for cheap. The seller also included the tools I will need to modify them.

As my choice of valve springs will depend on what cam I use,
what cam do you recommend together with modified Vortec heads on a car like mine?


These valve springs/retainers/locks are told to bee good for up to 0,590" lift, with no clearance problems and to fit right on the Vortecs with no modification:
http://cgi.ebay.com/ebaymotors/ws/eB...K%3AMEWAX%3AIT

If I go this route, I don't need to machine the heads at all, except enlarging the push rod holes and switch to 7/16-14" threaded screw in studs.
Comments?

[NXS]

vortec heads respond well to cams with 224-235 in HYD roller setups pretty nicely. the 224 cam will stock near stock, by 230* you will hear a little cam and by 236 you will have a cam with a nice sound to it, and perform very well.

if it were mine i would go with the 232-234* cam

[TNshadetree]

A good proven cam that matches well with the Vortec is the GM Performance hot cam. Here's a nice write up on it.

http://www.chevyhiperformance.com/te...ams/index.html

I am building a Vortec based 350 and I purchased the Hot Cam kit that includes the roller rockers, but the cam can be purchased separately. Check Scoggins Dickey for pricing.

[staleg]

Thanks for your answers!

Will springs suitable for lift up to .590" be too stiff for a .525" lift cam?

[NXS]

you need to be looking at spring rates, a 590" solid roller spring is way different then a flat tappet spring....

[ap72]

For a stock set of Vortecs I woldn't go much past a 220 duration at .050" on a 350. If you do you're just making noise, not power. HOWEVER if you do some bowl and port work you can extend tha range by a very healthy margin.
Also you'll need to machine the guides to prevent yor retainer frm smacking into your valve seal.

[staleg]

Ok, I will check that out.

But the springs in the link in my first post is told to be for a hydraulic roller cam with max .590" lift. Wouldn't that fit my OEM roller engine?

And the retainers and locks in the same kit will cause no guide to retainer clearance problems on Vortec heads, according to the seller.

[NXS]

ap72, a vortec head on a 350 needs a 236 @ 050" cam to reach it's full potential and if you read his thread he has found a seller on ebay that provides a setup that is good to 590" lift with vortec heads.
I do the same by using a dirt track solid lifter 1.25" spring (with damper removed) and different valve seals, he uses a different retainer.

at any rate to answer his question, these springs will be fine for a oem hyd lifter.

[ap72]

Well I guess cam opinions are like ***holes, everybody has one and everyone thinks theirs doesn't stink.

I don't know if those retainers will work with stock rocker arms.