Pi engine and 3650 swap need help on speedo

green_fow_six

Founding Member
Jan 21, 2002
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16
Martinez, CA
Just did an engine and transmission transplant on my 96 GT!!! :banana: woo hoo. Everything seems to be functioning well except for my speedo. The new tranny doesn't use speedo gears, it is all electronic. needless to say, my speedo is not correct anymore, I think it read 100 mph going about 20.
Anyone know how to fix this? Does the SCT programmer work for 96-98 to fix the speedo. would it even work since my 96 computer is mated to a Tremec 3650? Would an electronic speed calibrator work. any info would help. BTW I have 3.73 gears and previously used a 23 t gear(still wasn't totally accurate but manageable. Thanks.
 
green_fow_six said:
Just did an engine and transmission transplant on my 96 GT!!! :banana: woo hoo. Everything seems to be functioning well except for my speedo. The new tranny doesn't use speedo gears, it is all electronic. needless to say, my speedo is not correct anymore, I think it read 100 mph going about 20.
Anyone know how to fix this? Does the SCT programmer work for 96-98 to fix the speedo. would it even work since my 96 computer is mated to a Tremec 3650? Would an electronic speed calibrator work. any info would help. BTW I have 3.73 gears and previously used a 23 t gear(still wasn't totally accurate but manageable. Thanks.
Call up Dallas Mustang and tell them you need an extended range speed cal. It costs about $100 and will fix your problem. I put a 3650 in my 96 and had to do the same.
 
wow you did the same thing I am going to be doing in a couple months. Anyways Did you do the swap yourself or have a shop do it? If a shop did it, how much did you pay for the swap?(if you don't mind me asking) and if you did it yourself what was the level of difficulty? I was just going to do the PI head and intake swap but dicided that my engine would need to be rebuilt not far down the road (130,000 miles) so might as well just swap a younger 99+ engine in since they are fairly cheap with low low miles. Is the speedo the only problem you have with the swap? I would greatly appreciate any info. Thanks!
Josh
 
Vette eater, I had a shop do the work but I ran into a few hitches. I planned on putting on some BBK longtubes in since the engine was coming out. First of all, the tr 3650 had a different mounting bracket, the mechanic modified the original mount to get it to fit the frame. Then the LT's had almost no clearance on the passenger side. He tried lowering and raising the engine mounts but it didn't help much. Also, the BBK midpipe would in no way fit! It didn't line up with the headers and the transmission mount was in the way of the CATs. I don't know if I received defective LT's or the wrong midpipewhat? What a piece of crap, anyways I ended up just getting the FORD shorty ceramic headers since I didn't have the time to keep my car in the garage too long. Other than that, he reused the old alternator and coil brackets, fuel lines. The good thing is he only charged my $650, not bad seeing how he had to drop my engine twice for the headers. Hope any of this helps. I can probably take some pictures if you need but I will be gone on vacation the next 2.5 weeks.
 
cool thats around what I figured they would charge. That sucks that the long tubes didn't work cause I was going to install long tubes when I do the swap as well..Guess that saves me a step. I am hoping to be starting on my swap around christmas time cause I figured that would be the best time to do it since I won't be driving it in the snow and ice anyways cause they are calling for a pretty nasty winter this year here. I am hoping to spend only about $2000 give or take for the whole thing. I think that is very reachable goal spending wise. Also I have a BBK x-pipe will I still be able to use that with the 99+headers or do they have to be cut? Thanks for the info!
Josh
 
if you don't want to try Long tubes, you can go with shorty headers (JBA, Ford, BBK) and reuse your x-pipe or you can also transfer your stock headers(manifold) from your old engine to the new one and your pipe will fit as it does now. The 99 and up manifolds are dinkier and won't fit our 96-98 pipes. Good luck.