I have a 383 (480 hp) w/ AFR 190 angle plug heads, to be installed in a 70' El Camino ... w/ factory air. It appears that headers and clearance will be a problem. I would like 1 3/4" but might need to settle for 1 5/8 inchers. Will this size adequately let the engine breathe? Also, with "shorties", would the loss of torque be very noticable in this mostly street used engine? All opinions appreciated.

I doubt you'd notice the torque loss by shorter primary tubes...maybe you would if you did a back-to-back test.

1-5/8" would be OK. You don't lose too much power by the smaller primaries, nothing I'd sweat about anyway.

What kind of headers did you use when you dynoed the engine?

Not sure what is causing your clearance problem, but I am running 1-3/4" Hedman Elite's on a Big Block in a '69 Chevelle with plenty of room. In fact, I could probably run this set up on a tall deck block if wanted. Surprising, I even have plenty of clearance for a full size stock starter. I have been able to install the headers from both sides without lifting the motor or anything else. You really need to explore this a little more.

You can get away with smaller primary tubes when you run shorty headers IMO.

I agree that 1-3/4" primary long tube headers would be ideal, but 1-5/8" shorties shouldn't hurt too much.

Before you settle for something you don't really want check around a little more first. I'm pretty sure Hedman makes a 1-3/4" full length headers for an SBC -- check p/n 65101, these come painted but you could get them coated local if you wanted.

if you decide to run 1 5/8" tubes i would definately run the long tubes. you might lose 5hp up top but you'd have 20-25lbs/ft more torque where you need it. but i think the 1 3/4" headers would ultimately make more power on an engine making that much hp. that's a pretty stout 383.

I think the Hedman's are for straight plugs only. I need to run a short plug in # 7 with the 1 3/4" tubes. Part # 66101

I think the boob I talked to at Jeg's is screwed up. # 4 plug doesn't fit either. Makes me think the Hedmans are better suited for angle plugs.

I need a graemlins/beers.gif