When retrofitting a TPI do you need a vehicle speeds sensor ?

If yes, who sells items for retrofit applications ?

Thanks

Yves

 

a VSS can be somewhat important but you can get by without it. however the ecm will trhow code and stall coming to a stop. as well as not getting into highway spark mode and a few other code features.

check out a company called stealth conversions. they sell VSS stuff. depedngin on your application there might be a VSS option for you give me some details. im might be able to help.

 

I put a TPI 350 In my Jeep and do not have a VSS for the ecm. The only problems I have is it has a high idle when you first start it up no matter what I adjust. Once it has been running and you shut it off and restart it it idles fine. Might be something in the prom that came with the ECM for the conversion, but who knows. Mine has never thrown a code but on the scanner it always shows it is in park/neutral even while driving.

 

check to make sure the correct iac is in the TB. you should get a p/n switch or flip the switch in the bin for manual/auto tranny. also the vss signal could be had with a screw in adapter from stealth conversions or try a local speedo shop. i belive youll need 4k per mile to go directly.im not sure on the pulse count so check around. however you could alway change the road speed constant to match it up.

oh check the painless wiring website they have screw on vss senders that fit on the trans screw on to the orignal speedo sender housing and then have a adapting side for a speedo cable to plug into.

60115 is the p#
here the webpage its on.

http://www.painlessperformance.com/fiacc.htm

 

To give you more details about the application.

The retrofit is a 305 TPI with the injectors changed for a 350 engine.
The car is a Corvette 1979 with a manual trans and for the rest a 3.70 rear end (trans is a short ratio muncie)

the ecm is 1986 Vette.

I saw the manual trans enable/disable code in the bin. Is it enough to change it from auto to manual ?

Thanks

Yves

 

Even if you opt to not use the VSS you can disable diagnostics
on the switch table,And if your versionn does not have it Tunercat would probably be glad to help you with that.

 

TA I'm new at this, which diagnostic codes do you mean ?

Thanks

Yves

 

I believe its called vehical speed diagnostics error in the switch table. Uncheck that box.