Author Topic: Question about 'porting' six pack manifolds  (Read 858 times)

Offline Road_Runner

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Question about 'porting' six pack manifolds
« on: November 27, 2011 - 10:02:24 PM »
OK, I think I'm going to start gathering parts for my stroker build for the Roadrunner and I'm really liking the idea of the 440Source Super Stealth heads, BUT I'm concerned that the heads may be overkill with my plans to use a six pack setup.  The Roadrunner has the fresh air hood so I'm limited in manifold choice and already have the six pack setup ready to go and really want to use it.  I have an original B motor Mopar Part # intake that I will use if I don't have to modify it, but if I need to hog it out to flow enough for the Super Stealth heads I'll get a new one to cut up.  So does anyone here have experience modifying six pack intakes to flow big numbers and how successful were you?

Thanks in advance, Jim
1970 383 Roadrunner Tor Red
1973 318 Barracuda Mist Green
2014 Mustang GT/CS Convertible All Black




Offline Challenger6pak

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Re: Question about 'porting' six pack manifolds
« Reply #1 on: November 28, 2011 - 12:23:44 AM »
My guess is that you will need another intake to modify.  The one I would recommend to ask this of is Chryco.  He has a lot of experience in this area. I'm sure there are others here that can help also.
1969 Sport Satellite H code convertible, 1970 Cuda 440+6, 1970 Challenger R/T 440+6, 1970 Challenger 383 R/T auto, 1970 Challenger R/T 383 4 speed,1971 Challenger convertible.

Offline Chryco Psycho

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Re: Question about 'porting' six pack manifolds
« Reply #2 on: November 28, 2011 - 08:07:00 AM »
it is very hard to really increase flow dramatically in the 6 pack , being a dual plane the lower plane is virtually inaccessable , I have opened the bores to match the the carbs base , blended the curve into the runners under the carbs & opened the ports into the heads with no problems but the increase would not be huge . I would still use the SS heads though 

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Offline Road_Runner

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Re: Question about 'porting' six pack manifolds
« Reply #3 on: November 28, 2011 - 11:04:13 AM »
it is very hard to really increase flow dramatically in the 6 pack , being a dual plane the lower plane is virtually inaccessable , I have opened the bores to match the the carbs base , blended the curve into the runners under the carbs & opened the ports into the heads with no problems but the increase would not be huge . I would still use the SS heads though

I'd rather use the original intake for that "70's correct" look, and since it sounds like its not worth modifying I can go ahead and use it as-is and run it with the ss heads.

Thanks, Jim
1970 383 Roadrunner Tor Red
1973 318 Barracuda Mist Green
2014 Mustang GT/CS Convertible All Black