Custom header question

[buckenbronco]

So I have a 363 stroker with a supercharger with a 4r70 and a np205. Builder says I should have about 650 horsepower to the wheels. He also said it would be better to run 3 inch exhaust with a 3 inch collector. I have a local header builder that can build what ever will fit. I will not have the bronco ready to bring to him for a couple months. So my question is what size tube can you fit between the fender and engine or any input from anyone who has done this before.

 

[pcf_mark]

I have made custom headers and I would not even try it without the truck fully assembled with all the bits and pieces in front of me. Select your primary tube diameter based on your heads and cam then it is all about trying to fit the right length into the space.

 

[nvrstuk]

What Mark said...do not build the header unless it's in the Bronco...

Yes, you will need 3" collector and probably 2" primaries.

What heads and blower? Matching 2" primaries to most SBF heads ...

I'm interested...

 

[u10072]

Do whatever the engine builder/header builder says. I’ll just say this- nice headers start being built at about $2000 and with that said I would have everything bolted down tight and ready minus the exhaust.

 

[68ford]

What did those leaf springs ever do to you? ;D

 

[Apogee]

What did those leaf springs ever do to you? ;D

No doubt...they're probably not long for this world once that thing is road worthy. That said, I wouldn't even bother trying to keep dual 3" exhaust with a cross-over between the frame rails, especially if you're going to try and exit out the back or behind the rear tire, but if you do, I'd love to see pictures. I've seen it done with custom frames that were wider, but not that big in a stock frame EB.

Since you're going custom anyway, fenderwell exit and run outside the frame rails...the question then is to where? Side dump in front of the tires can be loud and stinky. If you're running full-width axles, you might be able to run it behind the axle still, but maybe not. That's a lot of exhaust for not a lot of space IMO.

 

[nvrstuk]

buckenbronco--- I'm really interested to see some more info on your build if you're willing to share... 650hp at the wheels on a Bronco with 25-33% HP loss on a rear wheel dyno due to our inefficient Bronco drivetrains means you have got to be to be pushing 850 HP on an engine dyno...this is why I'm asking... sounds serious... be interested in hearing more info...


I've never heard of a Bronco with less than 25% efficiency losses thru the drivetrain...