where does the 10 extra hp come from that a 91 mustang has over an 89 both being 5.0s of course?

Question

I read a response to a question and the person said that a 1991 mustang 5.0 motor had 10 more horse power than a 1989. I understand that each individual motor even same year models will have a variance in hp, but to say that every 91 5.0 has 10 hp more than 89s I do not believe is right. they are both mass air induced and have the same specs. what am I missing? Thanks for your help.

Answer 1

Strictly in the computer. The 91's have a more aggresive tuning (air/fuel, Timing) map than the 89's

Answer 2

I do not believe that Ford ever advertised any hp amount other than 225 for the '87-92 5.0Ls. They are the same thing.

There were major changes from '86 to '87. In '89 they switched to mass air ('88 in Cali) but the output didn't change according to Ford.

In '93 they dropped the output to 205hp but that was only because they were measuring it differently. The only difference in '93 was the switch to hypereutectic pistons.

Answer 3

Specifically..I can't say....but from reading car mags,I know a small HP boost can be had by improving the airflow (like a k+n airfilter) or putting on a different exhaust (to reduce back pressure) or just reworking the engine computer.

Ford may have done 1 or all 3 when they went from one model year to the next.......

Answer 4

Put a K&N filter in the 89 and the box it sits in drill a few extra holes in it and you will get the extra10+ ponies you want