head gasket done, car feels slower

ndp7486

New Member
Apr 30, 2008
11
0
0
Minneapolis
i recently took the head off my car changed all the gaskets and timing belt , water pump, plugs, wires, cap, rotor, igniter. i tourqed the new head gasket to 65 ft pounds to be on the safe side and not strip anything out as this is the first major job ive ever done on my supra. but now my car feels like it has less power than before, but its much smoother through the powerband. i just dont get it! if anyone has any suggestions about what it could be, please give me some insight on it. thanks alot.
 

Poodles

I play with fire
Jul 22, 2006
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Fort Worth, TX
65 is too low... the proper torque is in the 70's (you can search for that answer)

There are a huge number of reasons it could be slower. Sensors out of adjustment, ect. Check for codes first off.

Make sure all your vaccum lines are hooked up properly as the GE's have a system that changes the path of the air in the intake...
 

suprahero

naughty by nature
Staff member
Aug 26, 2005
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Did you use the stock headgasket or a thicker one? You could have changed your compression ratio.......:dunno:
 

CRE

7M-GE + MAFT Pro + T = :D
Oct 24, 2005
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Denver, CO
WARNING: Car may run like ass after having been disrobed for extended periods. Be supportive and remember... she's the bashful type, ya big lug.



Uhh.... nope, can't say I recall that.
 

Poodles

I play with fire
Jul 22, 2006
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Well, if you reset the ECU and other things have changed, it will take some times for the ECU to make better maps...

I've always thought it would be a fun prank to pull the EFI fuse for a bit on someone's car so it runs like ass :D
 

ndp7486

New Member
Apr 30, 2008
11
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Minneapolis
either way ill double check the timing and adjust if neccesary, if it feels restricted again then ill try a new tps and see if that helps. im almost certain the tps on the vehicle has been there for 22 years.
 

ndp7486

New Member
Apr 30, 2008
11
0
0
Minneapolis
Poodles;1086316 said:
Well, if you reset the ECU and other things have changed, it will take some times for the ECU to make better maps...

I've always thought it would be a fun prank to pull the EFI fuse for a bit on someone's car so it runs like ass :D
what is the best way to let a ecu remap itself? city/higway? what about fuel types and air temp? are there any factors that could have a negative/positive effect on this?
 

amichie

New Member
Apr 13, 2006
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sYDNEy
ndp7486;1086325 said:
either way ill double check the timing and adjust if neccesary, if it feels restricted again then ill try a new tps and see if that helps. im almost certain the tps on the vehicle has been there for 22 years.

You can test the tps at the TDCL connector without removing it. Read the online supra tsrm to find out how. It's in the automatic transmission section from memory.
 

Clied

Wangan Supra
Jun 8, 2006
367
0
16
36
NorCal
After my BHG job my car had problems idling. Vacuum would be at 15 and slowly start dropping. I checked ignition timing and if any of those hoses were loose but I couldn't find anything wrong. I just decided to test drive it around the block a few times and in doing so my idle smoothed out and my vacuum went to 20. I think since the battery was disconnected for so long the computer just had to get use to the car running again(car was sitting for a little over a month). May not be the case for you but it worked for me.

I found from many people on the forums that the recommended torque specifications on stock head bolts is 72 which is what I torqued my head to. I also did a re torque after 5 heat cycles.
 

shaeff

Kurt is FTMFW x2!!!!
Staff member
Super Moderator
Mar 30, 2005
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If you don't have a TPS code, then why would you replace it? Are you made of money or something?