Author Topic: Magazine 431 build with 555 hp....  (Read 4996 times)

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WerbyFord

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Re: Magazine 431 build with 555 hp....
« Reply #15 on: July 17, 2018, 01:34:42 AM »
Good article - though for sure head flows leave us guessing  a little. I just cleaned up the Edels in the Gonkulator and it said
Torq 505 at 4700
Powr 551 at 6500
(To compare, you have to knock about 7hp off their results since they weren't driving the water pump)
Still, close enough given what we know and don't know.
Note the Gonk also feels like 6000 is way low for a peak.
A 950 Holley gonks about 17hp more, if that is really 650cfm at 1.5", wow, that's a small block carb!

The picture of the heads shows a heart shape chamber, doesn't look like the good old 1990s Edelbrock vintage, did I miss something there?
They don't say much about the heads other than that picture.

andyf

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Re: Magazine 431 build with 555 hp....
« Reply #16 on: July 17, 2018, 10:50:37 AM »
The only information in the article on the heads is that they were done by Maloney Competition in VA. If you do a google search on that you'll come up with a picture of a house on a country road. So your guess is as good as mine.

Personally I think a set of Trick Flow heads and a slightly smaller cam would make that engine work better but we'll probably never know.

mbrunson427

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Re: Magazine 431 build with 555 hp....
« Reply #17 on: July 17, 2018, 06:04:47 PM »
I just looked back at the cam Dema ground me for a BBM head 428, seems like the same basic deal, just bigger. Mine was 226@.050, .609"lift, 112 lobe centers, single pattern. Intended use is a '67 Mustang w/ 4 speed, street/strip use. Makes me wonder what design parameters he was handed.
Mike Brunson
BrunsonPerformance.com

westcoastgalaxie

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Re: Magazine 431 build with 555 hp....
« Reply #18 on: July 24, 2018, 11:32:38 PM »
I must have missed the solid roller part in the article, I guess my reading comprehension sucks as well. It would certainly be nice to know more about the heads, but Werby's gonk shows that there isnt anything magical going on there. I was also surprised by the low rpms, I thought at first it was hyd roller cam, but with a solid and the large of a bump stick i agree it falls off suspiciously early.

andyf

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Re: Magazine 431 build with 555 hp....
« Reply #19 on: July 25, 2018, 12:21:51 AM »
My guess (based on 20 some odd years of dyno testing performance engines) is that the heads aren't great and the cam is too big. That is a fatal combination. The big cam kills the low end power and the heads kill the top end power. I just saw this recently where a guy had some "custom" heads and a huge by huge cam in his SBC. The heads were big but didn't work very well and the cam was way too big for the engine. We put a much smaller cam in the engine and picked up 100 hp. There wasn't much we could do with the heads since the guy didn't have the money to replace them.


I don't think we'll ever know the answer for this engine though since it would require a complete redo to test the theory. But if a guy came to me with that engine and a stack of money I'd put Trick Flow heads on it and use a much smaller cam.