too much tb?

[96darkhorse]

when i installed my 70mm , i expected to gain some oomph...... but i actually lost power and torque, i noticed it right off the bat....i only have bolt ons and an eddy mani. i guess i might see and feel the results if i had aftermarket heads.....i notice alot of people install bigger throttle bodys when they do an intake swap and before a head swap.....have you guys felt any power loss???

 

[toyman]

when i installed my 70mm , i expected to gain some oomph...... but i actually lost power and torque, i noticed it right off the bat....i only have bolt ons and an eddy mani. i guess i might see and feel the results if i had aftermarket heads.....i notice alot of people install bigger throttle bodys when they do an intake swap and before a head swap.....have you guys felt any power loss???

During the course of a recent discussion I had with Accufab Tech support they told me the reason they dropped the 70mm TB (94-95) was because there were no performance gains with a stock engine.

 

[Grn92LX]

You didn't lose power or torque. Only way a tb can be too big is if its larger than the opening on the inlet. I have noticed some people who use the junky brand tb's report it sometimes feels different. I did not experience this when I swapped from a 65mm accufab to a 75mm accufab on my 302 as recommended by Ed Curtis @ flowtech induction.

 

['94ChickStang]

when i installed my 70mm , i expected to gain some oomph...... but i actually lost power and torque, i noticed it right off the bat....i only have bolt ons and an eddy mani. i guess i might see and feel the results if i had aftermarket heads.....i notice alot of people install bigger throttle bodys when they do an intake swap and before a head swap.....have you guys felt any power loss???

Yes I felt a loss of power, whether it actually lost power who knows...and I didn't use cheap parts. I may or may not swap my 65 back on, we'll see!

 

[Dino Dino Bambino]

Did you set the TPS voltage correctly (0.95-0.99v throttle closed)? Most aftermarket TB's have an adjustment for the TPS so you might wanna check it.
I had NO power loss when I replaced the stock TB with a Summit Racing 75mm unit. I just enlarged the upper intake opening to match the TB size.

 

[tstang21]

i agree as well. i dont think youll lose hp/tq with a 70mm. check the tps voltage and see if its in the correct setting. this happened to 1 of my friends that he installed a bigger tb. once he set the tps voltage right, it ran really good.

 

[Tom95gt]

How do you go about checkin the voltage?

 

[Black95GTS]

Don't fear the gear, go 4.10s!

Whoops wrong thread.

Adam

 

[Dino Dino Bambino]

How do you go about checkin the voltage?

Easy if you have a digital voltmeter. Pierce the insulation of the middle wire coming from the TPS with a sewing pin but without going right through. Attach the positive lead from your voltmeter to the pin and the negative to a ground. Turn the ignition on (engine off) and read the voltage. Loosen the adjustment screws and rotate the TPS until the voltage is in the correct range (0.95-0.99v). Tighten the adjustment screws and if the voltage stays within range, you're done.

 

[tstang21]

:

Don't fear the gear, go 4.10s!

Whoops wrong thread.

Adam

i was about to say the samething also