I have a stock 06 GTO. Can i run a 85 mm Borg warner turbo setup on stock block? Or could that turbo be too big?
I wana do the L92 heads first but will that even make a difference?
Thanks

 

you could run any turbo as long as its bigger than a 76mm on the 6.0 LS2 for it to be nice and efficient. There is such a thing as TOO big so yea i wouldnt go over 88mm on that especially being a street car and especially a stock motor at that. Anyways a borg warner 80mm (S480) is like $899 from most places and its good to 1100hp and imho its the best bang for the buck, or you could also get another borg warner for about $600 but it would be a 72-74mm but basically the same turbo on the exhaust side (just flow alittle less due to the smaller wheel up front). As far as L92 heads go making a difference, uh yea. lol They are badass heads and will only compliment the entire setup. They kick any other stock heads *** as far as flow goes... good luck with everything

 

There have been a couple guys break 700rwhp on stock LS1 and LS2 motors, they just dont last forever and your tune has to be excellent for it to last any amount of time on boost...other than that anythings possible we see it here all the time

 

The flow characteristics of the l92's are excellent to say the least. For a stock head, they're pretty much the mack-daddy of them all. They're only going to help you, so yes, do them first if you plan on going FI.

As far as sizing your turbo, it's already been mentioned that there is a factor of deminishing returns with regards to size. I'm going to use a Precision T76GTS with my 6.0L build, only because my car is street driven and I want the boost all-in by 3000rpms (give or take). An 80mm would probably be a good alternative if you're looking to grow into something in the future.

 

85mm is what I got, looking for 1K WHP. Gotta get that fuel system right.

 

Yea i figured for when i wanna turn the boost up and get to the 700 make i would have to do pistons and rods, is that big of a turbo gona be terrible for low boost like 6 or 7 pds. Like building boost really slow.

What kind of fuel mods must you do besides injectors and fuel pump?

 

Bump for answers. ;-)

 

The 85 is not going to get rolling fast under 10psi. We used a 74 on Daves ls-2 and it made 735/745 to the tires at 15psi and comes on pretty quick. Thats too much turbo for a stock bottom end. Its a good unit for above 800hp though.

 

Changing the stock heads for l92's will be a waste of time on the stock shortblock with boost. You will already be able to make enough power to blow the bottom end. If you do decide to forge the motor and up the boost, go for an aftermarket head with a thicker deck and better exhaust flow. The extra money would be well spent. If you were staying N/A, the l92's would be a great budget head.

 

The S85 will be a bit much for what you are wanting to do. To be honest, the TC76 will outspool all the units mentioned and make 700+rwhp. Its hard to beat that unit.

 

Hows the 80 mm look ? Still to big?

Well wat heads are good for turbo app?

 

80mm is a bit big for those cubes to be honest with you. The 76mm TC unit would spool much faster and still give you well over 700rwhp.

 

Ok i like the 76 mm. thanks for the help Doc

 

OK if i do the 76 mm borg warner turbo...... do i get the s300 or the s400?

 

I had a hell of a time packaging my GT42R turbos into my GTO!!!

 

S400 version....listed at the bottom of our site.

http://www.forcedinductions.com/productsborgwarner.htm