Header Help.

My A429's have been drilled and tapped for BBC flanges. I'm thinking now I'd like to go through the hood.
Couple of questions:
1) What size primary should I go with 2.125 or 2.25? Both sets have a 4" collector. Motor (466) makes around 525hp/600tq. Turns 6000-6200. Hoping to make a few changes this winter. Shooting for 650hp at 7200. Only want to buy one more set of headers for the next few years. It runs good now with 2" maddogs.

2) Will a set built for BBC point straight up on my heads? Meaning are the head angles the same?

I'm looking at Schoenfeld Truck/Tractor line.

The head angle is not the same, and if your buying headers once for whatever you build later , I would probably buy the 2.125 dia. Through the hood headers don't have any compromises like chassis headers do. I have 2.125's on my 557 and it made 861 hp. I doubt the 2.25's would gain you much and the 2.125's will help you small motor now.

JMHO

2.125" headers will leave you a lot of room to grow in the future. It isn' that hard to "adjust" the angle on the headers once you find out how they fit. A buddy of mine did a dyno test with downswept headers vs. the Schoenfeld uprights and gained about 40hp. The downswept were 2" vs. 2.125 for puller headers.

IDT-572 wrote:The head angle is not the same, and if your buying headers once for whatever you build later , I would probably buy the 2.125 dia. Through the hood headers don't have any compromises like chassis headers do. I have 2.125's on my 557 and it made 861 hp. I doubt the 2.25's would gain you much and the 2.125's will help you small motor now.

JMHO

That's what I was thinking. Although I was hoping they would fit.
I'm looking to use the BBC holes to get away from the crimp my headers have now, around the bolts.

schmitty wrote:2.125" headers will leave you a lot of room to grow in the future. It isn' that hard to "adjust" the angle on the headers once you find out how they fit. A buddy of mine did a dyno test with downswept headers vs. the Schoenfeld uprights and gained about 40hp. The downswept were 2" vs. 2.125 for puller headers.

That sounds pretty good.

They don't look all that bad really.



I Cut and added the Flowmaster Merge Collectors on mine.There tall but no way are they hillbillyish.

Sweet. I could live with that.

TRUKPULR wrote:They don't look all that bad really.



I Cut and added the Flowmaster Merge Collectors on mine.There tall but no way are they hillbillyish.

Nope, that aint hillbilly, that looks kick-a$$!!

Bill