1968 327 reubuild, vortec heads or not?

[lil hoodlum]

I hear what everyone is saying about the double hump heads and that the Vortecs flow so much better. That is one of the reasons why I was on board with using them hence why I purchased the ProMaxx units as I thought the earlier style intakes would bolt on. They are advertised as being drilled for both the vortec style intakes and the non-vortec intakes.

With that being said I am considering purchasing these aluminum heads 185cc intake runner, 72cc combustion chamber, 2.02"/1.60" valves. The heads are still ProMaxx Performance, just not vortec style.

http://www.jegs.com/i/ProMaxx-Perfor.../2171/10002/-1

[Marshy]

You might want to ask him what the quench distance is and if you can run a thinner head gasket to gain a little more compression with those larger style heads. I recently ditched my 0.040" thick head gaskets (FelPro 7733PT2) for a thinner 0.015" gasket (FelPro 1094). The change in thickness and diameter of the fire ring reduced the combustion chamber by 5cc and gained a half a point of static compression. I figured it went from 9.1:1 to 9.6:1, and runs fine on regular octane still. It could be more or less for you depending on your cylinder volume, don't assume you'll gain half a point in compression too, you need to run the numbers.

[lil hoodlum]

Just to update everyone, I ended up going with the ProMaxx Performance aluminum non-vortec heads, the 72cc ones.

The engine was broken in on the dynometer at the machine shop who rebuilt the engine. Peak torque was 336.8 Lb-Ft @4200 rpms. Peak horsepower was 308.3 @5600 rpms.

I took the delivered the motor to another shop to do the motor swap. Finally a little over a month it is due to be installed Wednesday morning.

I am nervious and excitied to finally be at this point. I'm hoping everything goes well.

[lil hoodlum]

First picture of my truck delivering its new heartbeat.

2nd & 3rd photos are of the motor after painting Chevy orange.

[lil hoodlum]

I'm really hoping that I can get some photos of the final assembly before install. I am told they are doing the final assembly of the motor tomorrow.

I am going with a rubuilt 4 barrell Quadrajet.

[rcazwillis]

That will be a good engine for your truck. Those power ratings will work well for a daily driver. Enjoy.

[Spullar]

Those look like some nice numbers. I love the filler neck on the intake. Good luck on the install.

[lil hoodlum]

Just wanted to update this, the 350 has been pulled and the rebuilt 327 is installed. i have had the truck for just over a week.

[garyd1961]

I hate be a negative kill-joy but those numbers aren't so great. All your power is at the 4200 to 58OO rpm range way above your normal driving range. Also it will probably cost you more to drive than if you went with the vortecs and premium gas.
A GM vortec crate engine will beat those numbers by a long shot for just a little over $2000.
I hope you don't take this personally. I don't mean it as an insult to you in any way and I hope you get many years of good use out of your motor but I think your builder could have given you better advice.

[Mollzyie]

Very nice man congrats ... I've read through this thread .... regardless the final specs are for the engine , it's gonna feel probably a bajillion times better than the old motor .

[garyd1961]

Originally Posted by Mollzyie

Very nice man congrats ... I've read through this thread .... regardless the final specs are for the engine , it's gonna feel probably a bajillion times better than the old motor .

I agree.

[toolboxchev]

Well this has been up for a while and I would love to here if your happy with your build. Have you any afterthought on those heads? I have considered them for a long time with today's ethanol based fuels.

It does look fantastic with what you have wanted to accomplish. I complement even more your choice of valve covers.