Buick V6 Throttle adjustments

[MathiaS]

i did the bellmouth the day i got the car
i got a K 'n N panel Filter, extractors, High Flow Cat, 2.5" exhaust and the difference between the stock and 70mm TB was ridiculous noticed it instantly and when i boot it it goes harder than the stock TB which opened fully where the 70mm only opens about 60% plus down low the idle and coast is WAY smoother only bad part is the gear shift, since its an Auto

 

[Jonah 101]

Holding the gears too long?

 

[MathiaS]

yeah Gears up about 1k too late if your giving it any go but then again its a 19yr old Box lol found if i throttle back its all good with the changes so gunna go easy till i get the Dyno Tune

 

[MathiaS]

BTW Jonah u can get the Twin TB's for the Ecotec u need the manifold to suit

 

[Jonah 101]

Yeh thanks, but thats too much flow for what I have planned lol

My ecotec is the same changing gears, memcal made this better. im unsure if the VRs trans is controlled by the ECU though..

 

[Andrew426]

The VRs trans has electronic kickdown, controlled by the ECU based on the signal from your throttle position sensor, which is all on the piss now. You need a retune.

 

[The1]

the adjustment for a Larger TB in the tune is for the TPS Gain, a larger TB will flow more at lower TPS than the smaller TB. You can get away without it on manuals but still best to get it adjusted, with auto's it's more of an issue as the Line Pressure Tables are controlled on one axis via TPS. Also depending where you buy the TB the stop screw may not be adjusted properly, you should sit at 0% TPS 500mv and 30steps IAC as a guide at IDLE.

 

[MathiaS]

Thanks The1 and Andrew426 i noticed the stop screw was out straight away (idling at 1500RPM) dropped that back to where my old one sat RPM wise And learned all about the TPS Coasting along at 60 the Tacho would fluctuate around the 13 to 14 hundred RPM range erratically and i felt engine braking but this cleared up when i reset the IAC (with the 3k RPM on startup) and let out the stop screw Just right this seems to be perfect now i have also been playing with the settings and think i found a nice middle ground i have finally got it Right open (Swapped the cable Plate from my stock TB) and now when i put it down it gears down twice (tested this at 60KPH all times) whereas before only shifted once i have got it gearing up around the same place as it did on the old TB (around 300RPM above) now i'm still planning on getting this tuned in probably a month once i get my fuel gear just wondering if there are any other adjustments i should make or if this is going to hurt anything.
Thanks again for the help guys your all legends.

On a side note, anyone know if MRHDT in Dubbo is good??

 

[St3alth187]

Your in Dubbo mate? Nice..
Im in Nyngan lol

 

[LS1 James]

I wouldnt be doing any WOT runs until you sort it out. The fact that you're adjusting the throttle stop screw and are actually noticing a difference in RPM is proof enough.
The IAC steps on a standard TB need to be @ 30 and adjusting the screw should have no effect on idle unless it is physically open so far that your TPS voltages are too high (which is most likely the case here) You also would have had a code thrown for sure but you wouldnt have seen it whilst adjusting the screw under the dash. It would be a TPS reference Error code.
The CEL doesnt stay on all the time for it.