6-71 400b project

[68 Pure Fury]

Hello, Im new to forums, I need some help/info supercharging my 68 fury before I order parts. Getting ready to building a 400 currently has cast crank externally balanced 452 heads.i would like to know what i should do to prepare the motor for a 6-71 BDS, street driving conditions. I know I need to get the compression down around 8/8.5. also concerned about the crank blower hub clearance to the radiator, plan on running a 2v pulley behind the blower hub for alternator and power steering. things like what brand heads if need be, what head gasket would be best, cam profile. thanks in advance

 

[FURYGT]

My 2 cents is to talk with an engine builder that specializes in Mopar big block blower engines.

 

[MONC440]

Hello, Im new to forums, I need some help/info supercharging my 68 fury before I order parts. Getting ready to building a 400 currently has cast crank externally balanced 452 heads.i would like to know what i should do to prepare the motor for a 6-71 BDS, street driving conditions. I know I need to get the compression down around 8/8.5. also concerned about the crank blower hub clearance to the radiator, plan on running a 2v pulley behind the blower hub for alternator and power steering. things like what brand heads if need be, what head gasket would be best, cam profile. thanks in advance

Before we can help with any of your questions can you please let us know what you are expecting from the engine? You say street driving but that doesn’t mean much. You can put the 671 on a stock engine if you use pulleys that keep the boost at a low psi but you will not get a lot of bang for your buck. Tell us what your goals are and maybe we can help. If you’re wanting to make a bunch of hp and plan on high boost you need a totally different recipe.

 

[CBODY67]

CR down to 8._ level? It's already there.

I suspect you can end up with about 5psi boost, which is puny by modern standards, but was pretty good back then. Which might be about what BDS has designed the system for?

Rather than a 6-71 style blower, you might get better results from a Latham-type unit as that unit does not heat the incoming air nearly as much, which means more power at lower boost levels. It does not have the visual cues as the 6-71, though, if that matters.

In one respect, just bolting any huffer onto a reasonably stock engine will provide additional power, BUT more power can be had if certain things are more-optimized for the blower application. As I recall, the BDS system is more of a street system than purely for drag racing (as the orig 6-71 were used for). The one advantage is that any huffer can compensate for poor cyl head intake port designs. Which ALSO means an upsized exhaust system and headers will be needed.

What are recommendations from BDS as to cams and such?

Enjoy!
CBODY67