1989GTATransAm

iTrader: (3)

As most of you know GM went from a TPI style intake system to a LT1 intake to a LSX intake system.

IMHO the TPI and LSX style intake systems are basically the same concept. The runners on each are shaped like a candy cane and feed from a plenum located in the same area versus the runners. The throttle bodies are in the front on both systems. The LSX is packaged tighter due to the shorter length of the runners and the use of plastic technology. So by modifiying the TPI intake system as we are we are actually updating it to an LSX style if you will.

IMHO the HSR and Mini Ram intake systems are in the same family as the LT1 intake system. So to stir the pot it looks like GM went back to the TPI intake system as being the all around best way to do things.

Guest

I suppose in theory you could say that. The LS1 is a lot better design overall though... mostly because they eliminated issues with transitions that the TPI fails miserably at.

1989GTATransAm

iTrader: (3)

MadMax what you say is true. However with what we are doing with the TPI I think we are "approaching" that of an LSX intake. Shortening the runners to the LSX length and making the transitions better. IMHO the GM engineers just updated the TPI manifold.

Stephen

iTrader: (12)

Yep....It kinda seems like the LSx is "simply" a "reverse image" of a TPI. Still runners, shorter overall, but kinda like putting the plenum under the runners instead of above them.

Kevin91Z

iTrader: (1)

If TPI engines had 18 degree heads that flow 300 cfm, and straighter runners, we'd be just as fast as LS1's are stock.