58's and a stock turbo??

I think the B flow's more, check with Mr Haney, he has the flow #'s

 

I believe Mr. Haney said PDI's manifolds flow slightly more but the B's can be had for cheap at about any truck junkyard or repair facility.

I think you could get away with the 58's and a stock turbo for awhile. You will see a little more heat but watch the gauges you should be ok. The 58's don't flow a crazy amount of fuel like the 59's but they are a nice upgrade and burn fairly clean. It would be a nice match to a Michigan Stage 3.

 

Mr. Haney JUST answered this in the other forum. The question was asked about using a B model manifold.This is his direct quote...

I wouldn't do this modificaton unless you are over 750 Hp. A PDI manifold extrude honed is a better choice for a power gain at lower horsepower levels.

The advantage is less restriction, lower EGTs and a power gain with the B model manifold, because it allows the engine to breath, but it should be used with a non-wastegated turbo for optimum performance gains at higher power levels.

 

The B flows better, but hurts on a slightly modified engine. So I'd stay with the PDI below the 750 hp level and go to a B above this level.

 

RWHP!! is there any other,LOL