Kyle is right in some instances but the ecm is not a problem. Both ecms run the same, TBI is speed density and TPI can be either MAF or SD. The data line might have a different rate/speed but that isn't the speed of the actual mechanics. The TBI ecm is just as fast internally as any TPI ecm, both react instantly to TPS changes or you would have a good .5 second delay in throttle responce with TBI (which we don't). Just look at all the really expensive race EFI setups. They have less options than even the TBI ecms! Mostly because they aren't built for all around, not too many race cars looking for good gas milage (NASCAR but not efi!).
If you search for TPI and TBI in the archives you should look at the large topics (30+ replies). At one point I had a HUGE post that shut up a lot of the TPI die hards from bashing TBI. The real difference is this: Wet flow vs. dry flow
Both are efi but the TBI has some advantages common to the carb but at the same time has some of it's flaws. TBI is a cross between carb and TPI, it gives you a great EFI system that runs like a carb but with most of the advantages of EFI. A cross bread so to speak.
, Jon (350 TBI!
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