I done a 89 model motor swap into my 79 bronco.. The motor runs great no issues but the thing won't rev past like 4800-5000 its like its hittig a rev limiter but the motor was in a running truck before I took it out and it seemed like it would rev to the moon( the donor truck didn't have a tach). Anyone have any ideas what this could be? I've checked fuel pressure and it's spot on, so I do t know

Any help is appreciated and thanks in advance

 

This is a stock '89 motor?

How high do you think it should rev?

If stock, looky here at where peak hp and torque are, and you'll understand that it shouldn't be anywhere near 5000 rpms if it's a stock motor.

Engine_Specifications

"Sound" is not a reliable gauge of rpm.....

 

If it is EFI and you are using a stock computer it is a rev limiter.

 

I drove it one day cranked it up and it would rev to whatever then I cut it off then it wouldn't go above 5000 after that and that's the only time it's done it