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440 six pack car for Super Stock

find out where the car falls in the power to weight ratio in it's class. then get an NHRA rule book to see what's aloud in the class, then see if it can run on the index that the NHRA puts out for all classes.
Do they rate the motor at 390 Horsepower as the factory did? Or did they assign it a different horsepower rating? I think the Hemi's were under rated by the factory, probably deliberately! Didn't NHRA rate the Hemi's at a higher power?
 
Well I have the time and the car, but not the big bucks it looks like it would require to be a contender. Maybe we could get a group of six pack lovers together to create a package that would work. Interesting that Stage 5 heads are allowed, but not Eddys? But Eddys are allowed if you run a Pontiac or Ford? Guess the Chevy guys don't need any help! Ha!
check the rules to see if you can run larger valves. i've got a set of stage 5's that are at least as good as OOTB edelbrocks. the pontiac, ford, and buick edelbrocks use stock valve sizes. you need to do a bunch of research. there's no telling how much money is just thrown at the chassis. definitely out of my league.
 
Do they rate the motor at 390 Horsepower as the factory did? Or did they assign it a different horsepower rating? I think the Hemi's were under rated by the factory, probably deliberately! Didn't NHRA rate the Hemi's at a higher power?
6paks used to be factored down a little; don't know about nowadays. NHRA factoring up the hemi probably contributed to their decline in some classes. a stock street hemi made 390-410hp according to the factory. the only mopar engine that i know of that wasn't over rated was the 340.
 
Looks as if an NHRA approved version of the Performer RPM head (60917 with an 84 cc combustion chamber) IS allowed in stock or super stock. As well as the MP 452A. Not sure how recently this happened.
 
I think a 906 with a modern valve job can equal a EDE RPM, my guess only. I've got EDE RPM heads & they don't seem to make any more power than I got from my home ported 906 or 915 heads.
 
i think the stage 5's i have make more power than edelbrocks. if your taking off a pair of stock unmodified iron heads then the edelbrocks will make a noticeable difference. if taking off a good set of iron heads for a set of edelbrocks i doubt there's big gains.
 
The 1969 Road Runner 6-bbl is listed by the factory at 390 HP. NHRA factors them Stock 380 HP and SuperStock 385 HP. With the replacement aluminum heads they are rated Stock 400 HP and SuperStock 385 HP.

In 1970 NHRA has 3 stock head factors 399 HP, 393 HP, & 390 HP. While aluminum heads are, SuperStock is 410 HP, 422 HP, 395 HP. I don't know exactly is going on with 3 factors, but some of it has to do with the transmission being stick or automatic.

And that all depends upon me reading this correctly..........
http://www.nhra.com/competition/classification.aspx
 
Guy running NHRA tells me that in Super Stock you have to keep the valve sizes that come with the heads and meet the port volume sizes but you can weld the fire out of the aluminum heads and move the ports around to your hearts content.
 
I believe this is the intake mentioned above. Yes there are lots of modifications published in the Mopar Encyclopedia Engine Book. All were performed on this one, and it won't run nearly as fast as my stock 6bbl intake. I messed with this thing for years, and multiple motors. Finally I gave up on it. My buddy had to have it. He mounted it on his car and it slowed down by .4! I like to tinker, but that thing owned me!!View attachment 375991

Damn, hard to believe the Weiand would not work well.
 
Guy running NHRA tells me that in Super Stock you have to keep the valve sizes that come with the heads and meet the port volume sizes but you can weld the fire out of the aluminum heads and move the ports around to your hearts content.
Well that's good to know! Is welding and re aligning intake manifold ports also allowed? If this ever gets off the ground, I'll know where to take the Edelbrock heads for port work! The Summit site lists the 60917 NHRA approved head having an 82 cc combustion chamber. Does this head have the same ports as the Performer RPM head but with a different chamber size?
 
I've never had the NHRA approved Mopar head in my hands. I asked him about manifolds. The way he told me was, you have to keep the carburetors in "roughly" the same location but you are allowed to fabricate your own manifold if you wish.
 
OK, I suppose that's why the STR type manifolds were popular back in the day. The Rat Roaster! Ha. I've heard that they are obsolete now. Fabricating an intake manifold sounds difficult and expensive.
 
OK, I suppose that's why the STR type manifolds were popular back in the day. The Rat Roaster! Ha. I've heard that they are obsolete now. Fabricating an intake manifold sounds difficult and expensive.
$2,000 and UP!
 
As recall the STR & Rat Roaster manifolds were really hard to tune. I thought the Weiand six pac was pretty straight forward. Don't have any direct experience though. It took me a while to get my stock six pak set ups to work well. Too much bullshit from Chrysler guys. I doubt my stuff would be at all competitive in the SS wars. Lots of technology needed there.
 
We're having the cam tunnel bored out for bearings in a 5.9 Cummins we're building. In talking with the shop owner who runs in Stock Eliminator he says, and I believe someone else has already stated, it's going to cost $100,000 to get a car ready to be competitive in Super Stock. I saved my nickles and I saved my dimes...........
 
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As recall the STR & Rat Roaster manifolds were really hard to tune. I thought the Weiand six pac was pretty straight forward. Don't have any direct experience though. It took me a while to get my stock six pak set ups to work well. Too much bullshit from Chrysler guys. I doubt my stuff would be at all competitive in the SS wars. Lots of technology needed there.
STR 14 wasn't bad to tune at all. The Weiand six pack tunnel ram was a disaster!
 
I think a 906 with a modern valve job can equal a EDE RPM, my guess only. I've got EDE RPM heads & they don't seem to make any more power than I got from my home ported 906 or 915 heads.
I agree with this. I just put CNC'd Stealth's on my RR to replace a well done set of 452's. Not much difference other than the weight. Need to get into the more serious heads to make real power. Maybe the next engine; )
 
Ok some of you guys know a lot more than me.
...the fact that it was a "disaster' shows I don't know too much...lol. I just spent a lot of time with the Weiand and the STR-14. The STR was a cross-ram though...not a 6-pak.
 
I think the STR had a couple different tops you could put on it. One for a single 4 barrel, and one for three 2 barrel carbs. I have seen pictures of both tops. When using the six pack top, you had to modify the manifold to make it (hopefully) distribute fuel better.
 
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