I have a friend who has a 99 Suburban 4x4. He said it is a 5.7, which engine is it? I thought the last year for the LT1 was 97? Anyway, he wants to put an exhaust on it and doesn't know if he should do a cat back or add headers and go from there. Anyone out there with this vehicle?

 

It is not an LT1, it is the L31. If it is a Vortec 350. I have the same motor in mine, it started in 1996.

Yes, put some headers on there, then cats, xpipe, and mufflers. For headers I recommended the Doug Thorley ones as they are mid length and not the short length. You can even get the Pacesetter long tubes which you would have weld the EGR to it as it is an OBDII vehicle.

 

Thanks for the reply. I have never heard of an L31, it is a Vortec 350. Are there any smog legal headers for here in Califoirnia for that model?

 

Yes, I am in California too and passed with my Doug Thorley headers. I bought them from Summitracing for about $430. It comes with the Y-pipe too. After that you connect the stop cats to them and then put on new mufflers. I chose to go with an X-pipe and dual bullets after. It is a little loud for me and I plan on replacing them with Hooker Aerochambers.

 

Not trying to jack the thread, but I'm assuming these headers would fit on a 2wd 99 Yukon, right? My girlfriend is looking into buying a VERY clean 99 Yukon with 90k miles, lady driven for 8000 cash. Very smooth running. I was lookin on Summit Racing and saw some cheap summit racing headers. Anyone ever used those? HOw's the fitment on them?

 

I had a bad experience trying to put 2wd headers on a 4wd. Maybe it would work the other way around. I am sure they make some for your model, anyway.

 

I wasn't asking if a 4wd header would fit on a 2wd. I was asking what headers are good and if the Summit Racing headers are worth it. They're kinda cheap, but if they fit well, I'll get them. Any other info?