[LS1] Manifold replacement

So the ls6 has a 70mm intake right? The 76/98 is bigger yeah? I couldn't find the specs on this site.

 

Until 2009 LS2, L98, L76, LS3 and LS7 used the same 90mm throttle body, yes bigger than the old LS1/LS6 which is called 78mm but has 75mm blade.

 

Cool man :spot on: did they go bigger again in 09?

 

No not bigger, brass plate and upside down (opposite opening) plate and bolt-on MAP sensor.
To simplify, early TBs like L98 were 90mm aluminium and generally called the LS2 TB due to popularity of those engines, and the later L76, LS7, most LS3 and of course all L99 and L77 have 90mm brass plates, generally called the LS3 TB due to main use in that engine.
Either one works. the ls3 one flows more and has a better placement of the throttle plate. and better overall machining of the housing.
I had both on my car before, ported, settled on ported LS3 TB by far. Have spare complete stock LS3 TB for $150.
Only points are the ls3 actuator is larger so its a tighter fit but it works, also the LS2 opens up. vs the ls3 opens down, so pay to check ETC scale for your setup.

 

Ahhh. See I couldn't find this info anywhere. I even looked through my chev ls book and it didn't have much info on intake manifolds.

Cheers!