PDA

View Full Version : TPI question


Draven94blackbird
07-19-2005, 09:14 AM
What years were the tpi's controled by speed density and not mass air flow? and what do you think is better?

foff667
07-19-2005, 09:23 AM
What years were the tpi's controled by speed density and not mass air flow? and what do you think is better?

gm kept going back and forth...i know my 89 was maf but my friends 91 was SD...they both have their good & bad points...i would definitly ask fasterthanyou as to which has more potential in the long run...in ls1 cars SD tuning is like the hot thing to do now...just takes a while to get each car dialed in right but once you do they generally make more power but dont adjust to outside conditions as well nor can it compensate for new mods very well...as a new tune is required for new mods.

Untamed
07-19-2005, 09:36 AM
I recall the MAF systems being more accurate with their readings since they took direct information from the MAF in the ECM, making the TPI units from 85-89 more fuel friendly. The Speed Density systems were from 90-92 (in the third gens) and used an average calculation in the ECM, allowing for more power in the low and mid range.

I think the Car Tech book on TPI said it best. Stacked against an LT1, TPI cars can still beat LT1's across an intersection, however the Lx1's have the better top end.

foff667
07-19-2005, 10:07 AM
in the end the maf is just one more restriction in the intake track...without it stock for stock the non maf car should make more power.

maroman88
07-19-2005, 10:21 AM
85-90 maf 91-92 SD

Batman
07-19-2005, 02:27 PM
in the end the maf is just one more restriction in the intake track...without it stock for stock the non maf car should make more power.

Possibly, but with a MAF it compensates better foor poor weather conditions, altitude changes, ETC. I think they both have their ups and downs but Ilike the MAF systems better for a street car.

foff667
07-19-2005, 02:44 PM
in the end the maf is just one more restriction in the intake track...without it stock for stock the non maf car should make more power.

Possibly, but with a MAF it compensates better foor poor weather conditions, altitude changes, ETC. I think they both have their ups and downs but Ilike the MAF systems better for a street car.

"but dont adjust to outside conditions as well nor can it compensate for new mods very well" i think thats what i said?

Tru2Chevy
07-19-2005, 02:49 PM
in the end the maf is just one more restriction in the intake track...without it stock for stock the non maf car should make more power.

Possibly, but with a MAF it compensates better foor poor weather conditions, altitude changes, ETC. I think they both have their ups and downs but Ilike the MAF systems better for a street car.

My speed density car runs the same in all weather condidtions.......like KOLL :lol:

- Justin