Jeffski

I'm in the planning process for my new engine, currently a tired L 48. I don't want to do anything outrageous. Pretty much stock rebuild of the bottom end, maybe increase in compression ratio. Have a couple questions.
1 What is the highest comp. ratio you can get away with and still use cheap gas?
2. Should I try to get a set of early heads i.e. 492's or go with the vortec heads?
3. Do you have to run special headers with the vortec heads? I know you need to have a vortec intake.

My goal is get somewhere around 300-350 HP. The car currently has 350 turbo, 308 gears, stock converter. I drive the car whenever I can. Also drive it on the Highway, I'm also thinking about a tranny swap to get the overdrive.

Thanks in advance for any tips or advice.

Jeff :cheers: :cheers:

69schemers

If you run aluminum heads, you can get away with 10:1. With Iron you should stay around 9:1.

The Vortec heads do flow more air then the older 492 heads. You would be better off getting a set of aluminum fast burn heads. They also will work with conventional intakes.

The Vortec heads do not require a different exhaust manifold.

The Money Pit

Your stock smog heads should get you close to 310-320 hp with the right cam.I'd recommend an Edelbrock Performer cam,and dual exhaust(preferably with headers)I hate to see people spend money where it's not needed when it comes to power.The 327's back in the late 60's made 300-350 hp and the heads were nothing special.

7T9Shark

With a 3.08 rear end, you'd better talk to someone at Comp Cams before you mess with a cam. You are going to be disappointed, especially if you are going for an ovedrive as well. Cammed motors like RPMs to really make the power. With tall gearing, you may even end up with less power than you had before. Remember, this is a small block that makes its power with revs.

For whatever it's worth.....