I'm thinking of swapping the TBI to TPI in my new vehicle. I'm wondering how much low end you guys lost when the TPI was ditched to a carb. I'm looking for some more low end.

 

I gained some torque from the swap to carb starting at around 2500 RPM.
My combo was specifically designed for low end and midrange from the beginning though. I think most people lose a good bit in the 1000 - 3000 RPM range depending on the combo. I've known of people losing around 50 lbft below 3000 RPM, but most people don't dyno at that low an RPM.

 

Im glad I went to carb but you will find others that say different. If I was gonna spend all the money to keep the TPI it would be worth it. Here is a graph from my swap. Stock TPI with shorties, headman y pipe and hooker cat back. I swapped to a 600 edelbrock, performer intake and a summit tpi cam. The cam might as well be called stock.

[IMG][/IMG]

 

Well this is going in a lifted K5 Blazer. I'm looking for tq under 2500 rpms. Never see it on dyno graphs, thats why I asked for some personal experience. I'm willing to bet its quite a bit in that range. I want the thing to get goin from idle and jerk the front end a little in the 1-2 shift, lol. I was even thinking about dropping in a 400 with TPI.

It does need to have a little bit of midrange for the highway. I remember my old S10 blazer had great off idle tq but the midrange sucked and it needed 75% throttle to go 70mph. Sucked the gas to say the least.