Grand national turbo headers fit 3.4?

[3.4grapeofwrath]

I was looking at these headers from a buick grand national and realized that they look similar to the 3.4 liter rwd motors exhaust port pattern. The 3.4 motor has two ports that are close to each other and the third port is farther away. The bolt pattern is not correct but could be modified to match up. Also the port shape is different but looks like it might work. Maybe with a little modding these could be used on our motors.
This would open up some options to turbo the 3.4 motor. I was thinking if anyone had a exhaust manifold gasket from a buick GN we could see if these headers could be used.

[ssms5411]

Re: Grand national turbo headers fit 3.4?

They look like they could be used for a 3.8 motor also nice find.

[darkflare999]

Re: Grand national turbo headers fit 3.4?

wow this would be awesome if it works for 3.4's!!

[FACTORYFREAK]

Re: Grand national turbo headers fit 3.4?

The bolt holes probably wouldn't bolt up to the 3.4 heads without modification

[3.4grapeofwrath]

Re: Grand national turbo headers fit 3.4?

The bolt holes probably wouldn't bolt up to the 3.4 heads without modification

I already said that in my first post but that's something that could be fixed.
The port alignment would be the most critical dimension and also the mounting angle 60 degree vs. a 90 degree motor. I'll have to see if I can dig up an exhaust gasket from a GN and check the alignment.

[3.4grapeofwrath]

Re: Grand national turbo headers fit 3.4?

I got a hold of some grand national exhaust gaskets to check the alignment of the exhaust port holes. It looks like if you center up the center port the outside ports are about a quarter inch off. I'm thinking if you cut the GN header flange off. Spread the two end pipes out and buy and weld a 3.4 liter flange (which they do sell) that this should work. Of course you would have to connect the two header pipes together somewhere. Next step is to find an old set of GN headers and check the fit on the 3.4 engine.