Thread: Put $$ into heads or rotating assembly?

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I'm still trying to decide on a combination to build a mid 300hp for my 65 Studebaker.

After pondering the combinations on Ryans car pages. I've pretty much rulled out a 400.

Would I be better off to put my $ in to some good heads and just rebuild the stock 350 rotating assembly, new hypereutectic flat top pistons. Will this support the hp?

or should I go for the 383 balanced rotating assembly. If I do this I'll be out of budget and will have to use my stock heads that I may attempt to port.

Already have Holley 750cfm, Edelbrock performer intake 2101

If this is gonna be a good street motor (at 350 hp, that's what it sounds like), I'd put the money in the heads and go for a cast or hypereutectic set of pistons. KB makes a 12 cc D-cup hyper that will yield 9.55:1 with a 0.039" gasket and zero deck with 64 cc heads.

Scoggin-Dickey sells Vortec head kits that include 12558060 heads (64 cc's) that have been modified for 0.550" lift, head gaskets, head bolts, rocker arms, Edelbrock Performer RPM Air Gap intake manifold, intake gaskets and 12-point intake bolts under part number SD8060AAG for $949.95

I see that you live in Michigan, so in the winter you'll have to let the motor warm up a little before driving 'cause these heads have no exhaust gas crossover to the manifold to warm the mixture.

Ya, I don't think I'll be driving it too far into the cold weather.

Interesting kit from Scoggin-Dickey. I'll have to see if I have the height under the hood for that manifold.

I already have a basic 350 rebuild kit with Speed Pro flat top Hypereutectic pistons.

I didn't see any specs on the heads thought.

Flat top pistons and 64 cc heads might give a little too much compression for street use. Under 64 cc heads, you will yield 10:1 compression with the piston set .015" below the deck and with a .039 head gasket. With 67 cc heads, you're looking at a 9.7:1 compression ratio. With 72 cc heads, you're looking at 9.21:1 which will run on whatever gas you put in there. World makes a head with 170cc runners and 67 cc chambers. It doesn't take much to make 350 hp and the 170cc runners of these heads would be excellent for the street. The combustion chamber looks a little dated, though. Dart makes a head with 72 cc chambers and 180 cc intake runners. It uses a much more modern combustion chamber which looks similar to the Vortec. The world heads will cost $800 for the pair and the dart heads will run you $1000. AFR makes the best street heads, but they will cost you at least $1200 for a pair. All of these heads will work with standard manifolds. For the cam, Comp's XE256H and dart's S/R heads made 330hp according to their dyno on 9.25:1 compressoion. I've seen numbers as high as 400 hp with different combinations of intakes, carbs, and heads and that cam. I am personally running that cam on 9.25:1 with Vortec heads and a dual plane manifold. It does make that power and it does make an excellent street cam. It makes more torque than a stock cam at every rpm, even off idle. It makes over 400 ft lbs of torque by 3000 rpm which is really useful when passing on the highway. It has no problem getting my truck rolling with 3.07 gears in the rear and a stock torque converter. For a litlte more performance, Comp's XE262H is the biggest cam they recommend for use with the stock torque converter. It still makes good vacuum and will idle, but it wont be perfectly smooth.

For the price difference in the World and Dart heads I can get a new set of pistons. Check out this link, is this the Dart head you are refering to. It has 67cc with 170 runners for $639 plus shipping.

http://performanceauto.us/store/prod...5d08c236ab7bc0

I have a cam that is close the the specs of the Comp XE262H, its the Comp 270H (pn 12-211-2). Rated a little higher on the low rpm 1800-5800, 270/270 adv dur, 110 lobe sep, .470/.470 lift

Where is a good place to shop for a good price on heads?

Should I have the assembly balanced? I don't think I will be running real high rpm's.

Originally posted by dcoffield
For the price difference in the World and Dart heads I can get a new set of pistons. Check out this link, is this the Dart head you are refering to. It has 67cc with 170 runners for $639 plus shipping.

http://performanceauto.us/store/prod...5d08c236ab7bc0

I have a cam that is close the the specs of the Comp XE262H, its the Comp 270H (pn 12-211-2). Rated a little higher on the low rpm 1800-5800, 270/270 adv dur, 110 lobe sep, .470/.470 lift

Where is a good place to shop for a good price on heads?

Should I have the assembly balanced? I don't think I will be running real high rpm's.

Comp. products has the same Dart heads for $560 plus shipping or the World Prducts heads for $ 730 plus shipping.I.M.O. these heads are a step up on the Vortec heads.

Originally posted by erik erikson
Comp. products has the same Dart heads for $560 plus shipping or the World Prducts heads for $ 730 plus shipping.I.M.O. these heads are a step up on the Vortec heads.

Do you have a link for them? Is one better than the other (Dart / World Products)?

Originally posted by dcoffield
Do you have a link for them? Is one better than the other (Dart / World Products)?

www.competitionproducts.com.The Dart heads look a little better as far as the castings.I don't have any idea about the flow numbers.I think the World heads will let you run the 2.02,1.6 valves but they are also more money.

Originally posted by erik erikson
www.competitionproducts.com.The Dart heads look a little better as far as the castings.I don't have any idea about the flow numbers.I think the World heads will let you run the 2.02,1.6 valves but they are also more money.

The Dart heads shown at Performance Auto says they have 2.02, 1.6 valves, unless it's a misprint.

Originally posted by dcoffield
The Dart heads shown at Performance Auto says they have 2.02, 1.6 valves, unless it's a misprint.

Th Dart heads I am looking at are called Iron Eagle S/S heads.

In heads this size, how important is the larger valves.

Originally posted by dcoffield
In heads this size, how important is the larger valves.

I would try and get the larger valves if I could but I would not get to excited about it.Another option would be to order them bare.They sell for $ 430 bare plus shipping.Then you could have a local machine shop build your heads then you could order the 2.02,1.6 valves for them.

Originally posted by erik erikson
I would try and get the larger valves if I could but I would not get to excited about it.Another option would be to order them bare.They sell for $ 430 bare plus shipping.Then you could have a local machine shop build your heads then you could order the 2.02,1.6 valves for them.

Check out this link. It looks like the same Dart Iron Eagle SS 67cc head but with 2.02/1.60 valve. About $120 more than the comp. product when you add shipping. Let me know if they are the same. I've emailed the store to see if the sizes are correct.

http://performanceauto.us/store/prod...e312ba3c4bf5a7

Originally posted by dcoffield
Check out this link. It looks like the same Dart Iron Eagle SS 67cc head but with 2.02/1.60 valve. About $120 more than the comp. product when you add shipping. Let me know if they are the same. I've emailed the store to see if the sizes are correct.

http://performanceauto.us/store/prod...e312ba3c4bf5a7

Yes they are the same.I would try and call comp. products and see if they could step the valves up to the 2.02 for a few bucks more.

I've sent them an email to see if they can upgrade the valves.

Do you know what style intake these take?