Hey Guys

As i am getting ready to swap in my new motor from a 97 TJ into my 89 YJ i pretty much have everything figured out but someone told me that the newer motors have a different CAM profile and that the newer camshaft wouldnt work well with the 89 EFI setup?? (I am using my old EFI and just swapping block and head from the 97 due to time and $$)

Is this true? If so, what causes that?

Other than that, piece by piece the motors are damn near identical.

Any opinions??

Thanks A Lot

Ok

Here are my Cam specs. Anyone have a FSM from a 97 TJ that can check these for the 2.5L?

Cam Lobe Lift:
-Intake: 0.265in
-Exhaust: 0.265in

Valve Lift:
-Intake: 0.424in
-Exhaust: 0.424in

Intake Valve Timing:
-Opens: 12 BTDC
-Closes: 78 ABDC

Exhaust Valve Timing:
-Opens: 56 BBDC
-Closes: 34 ATDC

Valve Overlap: 46

Intake Duration: 270
Exhaust Duration: 270

Anyone have a FSM for a 97 TJ 2.5L that can check these?

That would be great!

Thank you

This is just a guess..... assuming that the ECM's are the same on both engines I would venture to say the worst case would be that you need to get a PROM from the 97 to match the cam profile...

This also is assuming that the EFI components of the 97 are same as the 89. Such as sensor ratings, injector flow rates etc... You may be better off swaping the cam just to be sure.

Here you go Kevin.

Cam Lobe Lift:
-Intake: 0.255"
-Exhaust: 0.259"

Valve Lift:
-Intake: 0.4075"
-Exhaust: 0.4145"

Intake Valve Timing:
-Opens: 15.4* BTDC
-Closes: 58* ABDC

Exhaust Valve Timing:
-Opens: 52.8* BBDC
-Closes: 26.2* ATDC

Valve Overlap: 41.6*

Intake Duration: 253.3*
Exhaust Duration: 259*

Hmm

Thanks guys

think those small differences are a big deal?

I would swap them, to me it looks liket he YJ profile is a little more aggressive without being wasteful and it should work better with your ECM.

Hmm

Thanks for the replies guys!

I got a bit of thinking to do.

Main reason is, the motor i am going to swap in is a 12 hour drive to pick it up and i was going to get it next weekend.

Hmmm