Gn1 headers ?

[434nova]

I am looking to get some new headers and was wondering if anyone knows if the gn1 headers work with a 3 inch Terry Houston down pipe? Thanks

 

[pacecarta]

their KB headers... i would say no .. if your pipe is a true terry houston he did make some wide swing pipes but not as many as the std
if your 'houston' pipe is actually an atr then it should be ok with the KB style

the SE headers ? the standard houston should work

 

[TR Custom Parts]

Only the SE headers will work. KB style will not as the crossover pipe comes up into the motor compartment where the downpipe normally would be. Of course if you have the downpipe made to clear that type of header it WILL work but more than likely you do not. And buy them from a vendor that supports the board! http://buickgn.com/headers.htm

 

[434nova]

Does the se headers come with a 4 bolt flange option or is it just standard 3 bolt buick ? Thanks

 

[pacecarta]

if you go 4 bolt you wont be running a terry houston DP

 

[434nova]

Yeah I know that Pace I figure I could sell the Houston downpipe and now would be a good time to upgrade to a 4 bolt turbo.

 

[pacecarta]

thing about four bolt is you need custom fab to make it all work , there is no simple bolt up unless you enlist someone like cotton to build it all custom , the gn1 3.5 vband pipe has a 3.5 vband which doesn't fit most 4 bolt turbos which are 3"vband and that pipe swings wide into the fender well requiring cutting the plastic to fit
and you'll have to plumb the external wastegate, you may need to weld on a pipe and flange off the header (my TA perf 4bolt headers had a flange but it just wasnt right for my install ) ,and then plumb the gate outlet either to atmosphere or back into the downpipe as required for some class racing

 

[434nova]

I guess it's alot more involved than I thought . I'll just go with the se headers and keep my down pipe. Car will only be a low 10s high 9s at best. Just keep it simple. Thanks

 

[TR Custom Parts]

SE headers are not available with 4 bolt flanges. You would have to get a conversion flange and then would have to deal with a bunch of mods as mentioned.