Best Mopar engine for SSGT?
 

Just wondering what Mopar engine people think would make the best GT engine and why. Have been bench racing at the shop during lunch and discussed 340 360 383 and have different opinions. Lets here some more opinions. I like the 67 383 if NHRA would give it a HP break from the 68-69 since it has smaller E valves and AFB vs AVS Any thoughts?
Thanks

i, m buildinding a 400 to go in a 72 scamp for gt/ea[:-cheers-:]

sean ward
stk# 2882

What's the best head that ever came on a 383? That little stroke ought to be a killer deal with the right head.

"The future isn't what it used to be."

with heads from Eric at CFO flow will never be a problem on a 383...

I think the 906 casting was the best head for the 383, though I'm no expert. It's possible to get 300+ CFM out of one of those heads. 203 cc intake port and a 2.08 valve. I know of a 383 that made 620+ hp on the pump with more left in it.

Jared Jordan
7551 SS/BA

I think the 71 high compression 340 has a lot of potential on paper, but it may be hard on parts due to the high rpm it will require.

The 915 casting number has a closed chamber and flows as well as906's

The stage v head is best but not legal on a 67 383. The 915 is legal only on the 62 343/383. The small valve 915 may be and would be best. The 70 383 with the small Holley would seem the best combo. The 67 came with a small AFB and 516 heads or a similar casting which is the worst head ever made for these motors, Paul.

IHRA #9730 D/PS

Paul
NHRA blueprint specs list the 915 as OK for the 67 383. But with the 67 and 68 both at 300 hp for SS the AVS might be better (bigger) than the AFB.
Still think the B is a better choice than the LA based on HP ratings VS size.

RJ,

The 70 and 71 high compression 340's have a 2.02 intake valve. The 72 and 73 low compression 340's have a 1.88 intake valve. I am assuming heads with the 2.02 valve can flow substantially more air than the 1.88 with S/S style porting.

Charlie Walc ran one of the high compression 340's in S/S years ago. He said it was a fun car, but an expensive one.

Hi Stewart, I'm not sure if the 67 383 AFB has the weights in the rear or not. I have flowed the one without the weights and it was 565 cfm. The AVS is 635 and the 70 Holley is 645. These are clean stock carbs I had laying around, The numbers are rounded to the nearest 5. If the intake will be custom made the Stage V head which is similar to the 346 and 452 would be the best bet. If you use a store bought mani the 906 head can be an advantage. I would stay away from the 67. Paul.

Greg, for some reason NHRA says the 2.020" intake head requires the same intake port volume as the 1.880" valved heads, so I don't know there is much there once you sink the valve/fill in the floor. The piston is the only other difference, and I can get a piston weight at or below what the low compression 340's currently run.

Hey Paulie,
Sam Dillow is looking to contact you. Send me a message with a number he can reach you at.
Gmirza1236@aol.com

RJ, you may be right. The port volume may be restrictive enough that the bigger valve makes no difference. I understand that the area closest to the valve is the most important, and as you move back upstream, it has less effect. I certainly have no first-hand experience doing any port work. Perhaps Paulie, who has been posting on this thread, might have some ideas.

RJ, do you run a late model GTO? If so, how fast is it, and what modifications have you made to it?

I am not a mopar guy at all ... but it seems that wayne taylor , ken etter, Bob mazzolini have had pretty fast cars with the 318. i have no clue what year or car that combo is from .

Greg, e-mail me - carolinaperf@yahoo.com

The '70 Holley on the Road Runner/Super Bee engine (335hp) flows considerably more than 645 cfm. The primaries are 1.562" (same as a 600 cfm carb) and the secondaries are 1.750" (same as an 850 cfm carb). I had one on my flow bench recently and it was well over 700 cfm.

Stewart, you may want to contact Jim Fitzpatrick in Orlando.He does a fair amount of heads ..all Mopar I think.He seems to be very knowledgeable and alwaya willing to help.