Whats the biggest TB u can bot on w/ the ls6 manifold w/ out any madifications?
 

Whats the biggest TB u can bot on w/ the ls6 manifold w/ out any madifications?

going bigger than the opening wont gain you anything, I think the opening is 78mm but I could be wrong...

Port your stock one. That's about the best you can do. Dont have any dyno numbers but a buddy did some major surgury on a stock ls6 manifold and stock ls1 TB and used 6% more injector to get the same A/F on a wideband. It was alot of work.

will an 85mm bolt right on w/ a n ls6 manifold?

It will bolt on, but with a reducer to 78mm like i told you many times before. It is pointless to go larger than the opening of the ls6 intake. Why dont you either search or at least read through this post you posted 4 times already.

Now seriously stop making 4 separate posts for the exact same question, and please search from no on as this has been asked 1000 times before.

https://ls1tech.com/forums/generation-iii-external-engine/807812-whats-biggest-tb-u-can-bot-w-ls6-manifold.html

What these guys are saying is. If you were to take throttle blade out of a 78mm TB and try to stick it down the throat of an LS6 intake manifold, it won't fit. The throat is too small. So what is the point of buying a bigger TB other than wasting money. The TB may have the ability to flow more air, but the hole behind the TB can't.
What Doug did was totally take apart the throttle body, bolted it to the intake, filled in all parts that were thin with a type of epoxy. Then bored an 80mm hole through the whole thing. Then had an 80mm throttle blade machined and reassembled the TB. This was a ton of work and if you don't have the resources on hand it would be expensive. He works at a shop the builds American LeMans cars. These guys knew what they were doing and it didn't cost him a thing. I have no doubt that his car picked up some power.
However, your origional question of bolting on a bigger TB without modifications just got shot out the window. So back to your ? Yes you can, but you won't see any gains. If you insist, it is your money and your decision.

BTW, a stock LS6 intake necks down to 75mm just before opening up to the plenum.

thanks guys.