TH 350 in Turbo Buick

[lost2a6]

I'm working on a turbo Buick that someone has installed a TH 350. I'm going to install the alky kit along with the TT chip. As of now, the ECM doesn't know what gear that trans is in due to no longer having the harness plugged into the original 200 4r. Can I just install some pressure switches into the case of the th 350 and tie them into the proper wires on the original harness? I'm assuming that the wire would need to go to ground when the trans shifted to that particular gear. Also what color wire would go to 2nd, 3rd gear etc? Thanks!

 

[jasjamz]

TT chips use vehicle speed to make 1st, 2nd, and 3rd gear changes. Is the ECM reading vehicle speed?

 

[lost2a6]

I was under the impression that he used the input that came from the trans (2nd,3rd) to cut the timing back when it shifted into 3rd. I think that he uses the speed signal to ignore KR when you first hammer it until it reaches a certain MPH. But yes, the ECM is reading a vehicle speed.

 

[chris718]

I was under the impression that he used the input that came from the trans (2nd,3rd) to cut the timing back when it shifted into 3rd. I think that he uses the speed signal to ignore KR when you first hammer it until it reaches a certain MPH. But yes, the ECM is reading a vehicle speed.

Some chips use 3rd gear recognition to adjust timing.If yours does,use the third gear port on the trans with a normally closed pressure switch installed in it.The 3rd gear port is right under the cooler line in and out fittings on the passengers side of the trans.Be sure to not install the original switch that came on the valve body in that location as it has a bleed in it that will urinate all over the exhaust when the trans hits 3rd gear.The oil present in the cavity on the 2/3 shift will break the ground continuity in the switch and allow the ecm to recognize third gear has been selected.Terminal "C" is 3rd gear recognition wire.

 

[pacecarta]

eric can and usually does set up the chip to use mph for when third gear will be , usually the timing fuel will shift at 67mph

 

[lost2a6]

Awesome, thanks guys!