Question concerning heads

[Chris'69Mach 23]

I have the 351c in my 69 Mach 1 and am toying with trying to get more power. I have talked to a guy that seems to be a gearhead and he suggested to me to have the 2v cleveland heads ported, polished and to shave them.

 

Would this be advantagous to make a hp gain? If so, can someone explain the perks would be to have this done?

 

Any input would be greatful.

 

Thanks in advance!

[jholmes217 65]

The porting and polish is to get better flow. The shaving is to raise compression ratio. Both are good for more power, but there are some things to consider; Will the the port and polish job cost more than a set of aluminum heads? Will shaving raise compression beyond the safe use of pump gas. Without know more about what has already been done to your engine, I can't really offer more.

[RPM 1,190]

And there are 2 styles of 2v heads, open and closed chamber. As posted in several threads, and confirmed by me, if you have to do much work to stock heads, a/m alum heads are less expensive. Unless you just have to use the stock heads, I'd go aftermarket, which I did.

 

Bob

[fordguy69 24]

CHI 3V heads. The best street head made for the Cleveland.

[LindenBruce 27]

You could also get a set of Aussie 2v closed chamber heads too. It all depends on what mods your engine already has and/or what your future plans are. Look here for aussie heads. http://www.ausfordparts.com/

 

Bruce

[Chris'69Mach 23]

CHI 3V heads. The best street head made for the Cleveland.

 

With theCHI 3v heads, would I need to change out the intakemanifold too?

 

The only thingthat has been done to the engine is it now has electronic ignition.... everything else is stock. I have been told this from the original owner.

[fordguy69 24]

CHI makes manifolds too. Not sure if you can use other manifolds. Check out Kaase's web site. He sells and uses CHI stuff as do almost all of the SBF Enginemasters guys.

 

http://www.jonkaaseracingengines.com/

[Wycked69 20]

In all do respect, you dont indicate if you engine is stock or not. If your engine is stock, your not going to see much improvement installing CHI or any other aftermarket aluminum head with out also matching a CAM and intake to the head.

 

For a stock street motor, the stock 2V head is most beneficial over the 4V. I have never seen a stock 2V head with closed chamber except for the aussie head.

 

So if you motor is stock, then your buddy was at least pointng you in the right direction with the 2V head. By shave, I assume he was referring to milling the head to insure its flat and not warped for proper fit to the block surface. The end result "techncially" increases the CR but depending on your head gasket thickness, it could be a wash

 

The CHI heads are great but you will have to use a matching CHI intake. Also keep in mind that many of the aftermaket performance heads have raised exhaust runners.

[RogerC 136]

In all do respect, you dont indicate if you engine is stock or not. If your engine is stock, your not going to see much improvement installing CHI or any other aftermarket aluminum head with out also matching a CAM and intake to the head.

 

Stated it as stock 2 posts above yours.

 

Clean the 2V heads up with a port & polish then match up a cam, intake and carb.

[shaun071 62]

For my last 351C I used closed chamber "aussie" 2V heads. The only mods were 4V exhaust valves and hardened valve seats. With a mild cam, electronic ignition and headers it made around 370hp and ran 13.8 @ 102mph down the quarter in a 3700lb Falcon. Personally I wouldn't touch the ports themselves just clean up around the valve guide area. To run pump fuel you will need to open up the combustion chamber as the compression will be around 11:1. As always it comes down to cost. Here in Aus, the 302 clevo heads are worth $50-100 and reconditioned with the mods described only cost $500 all up.

[Chris'69Mach 23]

Thanks for all the input.