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#1 | |
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If you look at a Rule Book or go on-line and look at a Rule Book, the "rules" regarding aftermarket aluminum heads aren't written down anywhere. Must be written in the Super Top Secret Tech Inspector Only Rule Book!
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Billy Nees 1188 STK, SS I'm not spending 100K to win 2K |
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#2 |
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Billy, regarding the whole aluminum head deal, supposedly the aftermarket heads were allowed because supposedly usable production castings were getting hard to find. Considering the majority of the "allowed" heads were made in huge numbers, it seems odd to me that guys were having trouble scrounging up SB & BB Chevy castings, SB and FE Ford heads, SB & BB MoPar wedge heads, yet the guys with truly rare heads, like the 413 and 426 Max Wedge guys somehow manage to able to carry on. Just seems a bit odd. Maybe as a guy whose combination was not blessed with aftermarket heads,(or intake manifold), at least for Stock, I am somewhat skeptical .
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#3 | |
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Somehow, the Mopar heads are being treated as if the aluminum head is a different combo from the OEM head with it's own HP factor. Not the +10 HP over the OEM head that NHRA originally assigned.
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#4 | |
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Billy- What happens when the "aftermarket heads" get the HP hit? Does it effect the "stock head" HP Factor too? |
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#5 | |
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IMHO, if the aftermarket head (carrying a +10 factor) gets a HP hit then yes, it should affect the stock head. The point of my side of this conversation is that whatever the "stock head" HP factor is, the "aftermarket head" factor should be +10! These "aftermarket" heads were not handed out to be of any advantage other than that of access to the Racer. If the Racer chooses to take advantage of the ease of access provided by the "aftermarket" head then the Racer should be willing to accept the +10 HP/weight penalty.
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Billy Nees 1188 STK, SS I'm not spending 100K to win 2K Last edited by Billy Nees; 02-07-2022 at 01:08 PM. |
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#6 |
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Aluminum or replacement heads - Some received a 10 hp adjustment and others 5. On our 318 combo we petitioned NHRA for the 5 hp like our Chevy bros recd and we got it. Noticed some bb chevy also recd 10. Not sure the thinking with NHRA. Typo?
All the engine gurus i talk to say the aluminum head loses 15 hp apples to apples. I'm thinking untouched that is probably correct but with the better combustion chambers etc who knows. So if an aluminum is untouched there could be a hp reduction under the then current factored rating. I know our 340 aluminum ss cant compare to the steel head factor. +17 hp difference on aluminum, not 10 or 5. Last edited by Mike Volkman; 02-07-2022 at 04:33 PM. |
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#7 | |
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Maybe they (NHRA) could use their recently enacted Rescission policy!
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Billy Nees 1188 STK, SS I'm not spending 100K to win 2K |
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#8 | |
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How about the stock heads make one natural class but the aftermarket headed combos change the natural class. Oh and add in the combos that give you 2 carb options and 2 different hp factors then add in aftermarket heads! 6 different combos out of one original combo! |
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#9 |
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Dave I don’t think the 427/445 69 Camaro can run AA/SA with the shipping weight of 3096. Divide 3096 by 445= 6.96 p/w. The natural imaginary class is two class below the 7.50 to 7.99 weight break. Adding 222.5 lbs to the shipping weight of 3096 would be 3318.5 lbs. Divide 3318.5 by 445hp = 7.457 p/w, the car would still not be in 7.50 to 7.99 window.
I believe class cars can move up or down one class from the natural class provided there’s a class for it to fit in. That’s how I read the rule book, I could be wrong. Uncle Al was wise beyond his years. |
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#10 |
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I think the 1970 Hemi Cuda got changed as well. I believe AA/SA is a no go now. How one of the fastest production cars can't run the top class is a bit off. It is hard to tell all the changes unless you own 20 different combinations. I thought a 70 340 Duster could run D/SA but I see the factor is a natural F/SA now. All the 71 Charger combinations became heavier.
Paul |
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