Don Terrill’s Speed-Talk

Thanks for the input.

I have a "stock" '79 Ford 302. I need more muscle, but must be 'stock' Ford cast iron head. (rules).

First, I'm told a Ford 351C head will help. Will they fit my 302 block and intake?

Second, Are these really best?

Application, circle track, asphalt, stock class. 5500-6000 max rpm, 2bbl carb.

Need to make decision asap. Thanks.

racerx1622 wrote:Thanks for the input.

I have a "stock" '79 Ford 302. I need more muscle, but must be 'stock' Ford cast iron head. (rules).

yes

racerx1622 wrote: First, I'm told a Ford 351C head will help. Will they fit my 302 block

with some modification

racerx1622 wrote: and intake?

with some adaptors

racerx1622 wrote:Second, Are these really best?

not sure, which head, ported?

racerx1622 wrote: Application, circle track, asphalt, stock class. 5500-6000 max rpm, 2bbl carb.

Need to make decision asap. Thanks.

extra money in mods may
be better spent on carb porting .....stroking etc, etc

You would be better off finding a set of heads off of a murcury mountaineer. They are iron heads but the same ports as the gt-40 heads. Ford calls them gt-40p heads and sells them new through svo pretty cheap as far as heads go.

Before you use the gt40p , check out the spark plug angle and make sure it doesn't interfere with the exhaust manifolds /headers.
The plug placement is different than other 302/351w ford heads.
Also, what ever head you use make sure you keep your compression ratio up. It won't help much if you increase your flow but lower the compression.

The ports are so dam large on those C heads that a 302 cid motor is just starting to get into the bottom of its peak torque band at 5500! are you building that motor to buzz over 8k, cause thats where it needs to go with those heads.
The C heads flow some 280+ cfm@28" on the intake side.
351M heads may be a better choise, as these can be ported to a easy 240 cfm, or maxed out at some 270 cfm.
In stock form they flow some 215 cfm if I recall right with about half the port volume of the C heads and drop your torque band back down into a useable range for the cid motor.

Shopboss wrote:Before you use the gt40p , check out the spark plug angle and make sure it doesn't interfere with the exhaust manifolds /headers.
The plug placement is different than other 302/351w ford heads.
Also, what ever head you use make sure you keep your compression ratio up. It won't help much if you increase your flow but lower the compression.

GTP 40 heads are about the best flowing stock heads for a 302.But.....like the post sez, the plug angle will hit almost ALL 4-tube headers. One co.(can't remember which) make a specific application. The good news is...Hi=Po 289 manifolds will bolt right on. If your class calls for manifolds you are in....if not find that one co. and go from there. GT-P40's flow well...chambers are NOT huge like the Clevelands and WILL perform in your stated RPM range.
Just the sparkplug issue.
6sally6

IF you're real serious about using a CLEVELAND type head, on a 302 (8.2 deck) block, you might want to obtain a set of Australian 302 castings. They have small ports, chambers, and valves but respond very well to modifications.

I personally prefer the big ports over the small ones. It does require a bit of a different building approach, but if you get it right you'll know it - even from 2500 - to 6500 rpm.

Sounds like a good engine for the EMC.

Troy Patterson TMPCarbs.net TMP Carbs

Aussie 302cleveland 2v's are what you will need, 2v ports but smaller quench type chambers.

Are you OK with notching the pistons or changing them to one with reliefs for the Cleveland style head? Do they allow the use of the Cleveland canted valve cylinder head in your class? How far in or out of the hole is the piston now? Are you going to change the cam to match the heads or just run whatever you have? What fuel can you run and what compression are you looking for? Is the rpm limitation self imposed and if so why so low?

Either of the Cleveland heads will have the potential to kill a GT40 or GT40P. Looks like some of you might be surprised what a big canted valve cylinder head can do at reasonable rpm with 302 cubic inches. A lot of it has to do with the fact that a good cam guy can reliably get enough lobe area to make excellent power without having to use excessive seat and low lift duration to get it. Troy has some ideas on the carburetor side of things I'm sure. I then wonder how a bigger head is going to be such a problem with a two barrel carb choking everything off?

Can you use the iron Ford Motor Sport 351 N head? That would be an excellent option to consider.

steve25 wrote:The ports are so dam large on those C heads that a 302 cid motor is just starting to get into the bottom of its peak torque band at 5500! are you building that motor to buzz over 8k, cause thats where it needs to go with those heads.
The C heads flow some 280+ cfm@28" on the intake side.
351M heads may be a better choise, as these can be ported to a easy 240 cfm, or maxed out at some 270 cfm.
In stock form they flow some 215 cfm if I recall right with about half the port volume of the C heads and drop your torque band back down into a useable range for the cid motor.

Here a stock Boss 302 build that made peak torque with the way outdated stock flat tappet cam at 4,200 rpm. If you were to cam it completely wrong for this application what you're saying would be true. Think Chevy LS-x series engine.

http://www.hotrod.com/techarticles/engi ... Z_302.html

Are you talking about the 351w head or do you really mean the Cleveland 2v style 351m head? The 351-400m heads had a huge combustion chamber if memory serves me right. I wouldn't use them for anything.

I think the advice to secure Aussie 2V heads is sound. As long as its legal, there isn't any reason not to take advantage. The heads are reasonably cheap - $200-300 per pair - bare. (if have some if you are interested)

Now for the really good news...this type of combo is easier than it has ever been. This is going to sound like a commercial - but it's only because you can get just about everything at one place. Apologies in advance for any violations of protocol on that...

Tim Meyers in MN...

prepped 2V heads - with water mods - http://www.tmeyerinc.com/

pistons for most 8.2 combos - http://tmeyerinc.com/bosspage.html

Manifolds (single plane or dual) w/o the need for spacers - http://www.tmeyerinc.com/B&Aintake.html

Yes you can use those heads. You need to plug the water jacket holes on the deck side and open a hole for the intake water. Special pistons would be required. The heads can make good power at high RPM, but I would work to build as large of an engine and spin the motor 7K+.

Calvin Hill
Hill Performance
708-250-7420

Do your rules require that you run a 4412 500 cfm two barrel, or can you use the 650 cfm two barrel? If it's the 4412, there is more in fuel curve than cheating the venturi for more air.

One of the big advantages to running the big head be it the Australian 2 V with closed chamber or the 4 V, is the big valves. Camming is everything here - it can make it or break the combo.

Troy Patterson TMPCarbs.net TMP Carbs

Troy Patterson wrote:I personally prefer the big ports over the small ones. It does require a bit of a different building approach, but if you get it right you'll know it - even from 2500 - to 6500 rpm.

Sounds like a good engine for the EMC.

Troy Patterson TMPCarbs.net TMP Carbs

x2 the big port heads on the 302 only work poorly with the old style cam's intakes etc.
They make a great combo with intake floors raised, and fitted to our 302 clevo engine or the 302 windsor.
Very underrated heads.

The aussie 302 clevo head has the same ports and valves as the 351
clevo 2 barrel heads, just with a small chamber.