Stock KA24DE Header Question

[boznuttz]

Based on Bwana's recent "el cheapo build", I have been inspired to also see if I can fab up my own T3 manifold out of a stock DOHC header that I had laying around. I had a pretty good idea of how I would weld on the flange for a 38 mm tial wastegate, as well as the proper placement for a T3 flange as well. I figured that the way I was looking at would be a decent setup while also avoiding boost creep.

Upon actually taking a look at the manifold now, I notice that it really is not a log manifold style setup, but the 1st and 4th runners and the 2nd and 3rd are completely seperate, and may make this a bit harder to do. I'll have some pictures up later as to what exactly I am talking about.

[boznuttz]

[boznuttz]

It looks like if I place the T3 flange on the top area, the only exhaust gases that will reach the turbo woudl be from the 1st and 4th runner...unless I do a LOT of work and completely cut it open to connect all the runners. Does anyone have any experience or advice? I don't want to compromise the strength by eliminating the space between the two main sections.

[boznuttz]

Lol, has it even been done before?

[Nissan_240sx]

I've never seen/heard about anyone doing this... lol try it out

[boznuttz]

Bleh, screw it, lol. I got myself a used SSAC bottom mount T2 for 70 shipped that I'll convert to a topmount T3 mani.

[ghx407]

Bleh, screw it, lol. I got myself a used SSAC bottom mount T2 for 70 shipped that I'll convert to a topmount T3 mani.

Do it, it works great.

[LayNLow240]

it is not recommended to weld cast in any way. if you do try to weld cast, it WILL crack unless you do it the proper way which involves a lot of time. you have to preheat it, weld it, then slowly cool it down. and then theres still a chance it can crack.