327 300hp Rebuild

[Merrill Anders 32014]

I have a stock motor in my 65 with 130000 original miles 3:36 rear,all correct #'s and marking. Want engine to look orginal on the outside. What can I do inside to gain hp and make her sound a little healthy ie 350 cam or???

[Jim T.]

Re: 327 300hp Rebuild

Why not just keep your original 327/300 intact and pull it out and drop in a ZZ4 crate engine and enjoy the roller motors extra HP and the healthy idle. You could even use the 300's AFB on the ZZ4 and with adapters from GM you could use your original valve covers. That's what I did to my 70, the 350/300 is stored in the garage still in sight of the car it came out of.

[Duke W.]

Re: 327 300hp Rebuild

Install the L-79 cam, L-79 distributor vacuum can, pocket port the heads with a three angle valve job, and match the inlet manifold ports to the heads. This will give you about 40 to 50 extra HP up top with useable revs to over 6000.

Leave everything else alone. It will look completely stock. It will have a bit of lope at a 750 RPM idle speed, which would be detectable on a PV and a bit less low end torque, but your wide ratio four-speed and 3.36 gearing is pretty short, so the low end loss will not be too noticeable, From 3500 on up it will be a LOT stonger.

Use OEM or equivalent replacement parts for everything else including the standard 1.94"/1.50" valves. Flattop
hypereutectic pistons are a good bet, and set up the deck clearance and head gasket thickness to obtain a true CR of about 10:1. That way it should run without signficiant detonation on pump premium.

Duke

[Steve Jansky]

Re: 327 300hp Rebuild

You wont be able to use your original valve covers with the ZZ4 even with the vavle cover adapters becuase the Older Corvette valve covers lack the breathers that are needed on the newer blocks. Remember that the 327's have a road draft tube in the rear of the block in the center. Later model small blocks dont. I have a non original 350 in my '64 Roadster and want to make it appear original like the original 327/300hp but there is really no way without cutting holes in the valve covers to let the 350 "breathe".

[Steve D.]

Re: 327 300hp Rebuild

Duke

What is a PV ?

[Ed Jennings]

Re: 327 300hp Rebuild

Performance Verification

[Steve D.]

Thanks. *NM*

[Dale Pearman]

Re: 327 300hp Rebuild

Good Idea IF you want to always go like a bat out of hell on the public highways. You'd need the HP for 100 mph and above.

For neck snapping torque all the way up to 120 mph use the 151 GM 350 HP cam and install it advanced four degrees. Rhodes lifters will make things even better. You can go fast a lot quicker this way.

Dale.

[Mark Ring]

Re: 327 300hp Rebuild

Merrill,
I like the setup Duke and Dale recomend. I ran that setup for a few years in my car and realy liked it. Desktop dyno shows the 4 degrees advanced camshaft timing realy pumps up the lower end torque without any real penalty at the top end. If I were building it today, that is the way I would do it. Looks totaly stock and runs great without the hassles associated with more exotic setups that probably won't run any better.

-Mark.