View Full Version : IMCO Poweflow exhaust

10-14-2012, 12:17 PM
I have a chance to buy as set of slightly used IMCO Powerflow exhaust with the standard A risers for my 1988 454 22' Donzi Classic. Does any one know anything about this brand and can I expect a noticeable increase in performance from this exhaust?
They are $2553 new, what would be a good buy for a used set?

10-14-2012, 01:03 PM
I bought the two sets that came off the Noreaster which had 1100HP engines which the owner changed to 1500HP engines with Stellings. You should not have problems with their performance. Bill

Just Say N20
10-14-2012, 01:28 PM
It is generally believed that if all you are doing is switching exhaust, it is not likely that you will notice any difference in performance.

To benefit from a freer flowing exhaust system, other changes must be also made to the engine. Intake/cam/exhaust together make a system that should be designed with all the components "matched" together.

If you are going for a different look in the engine compartment, switching exhaust is fine. If you expect bolting on different exhaust to wake up some sleeping horsepower, you will be disappointed.

10-14-2012, 06:04 PM
Buy a 502, it'll be exciting in and of itself, plus it'll give you something to build on.
Generally, a 454 just isn't the price of admission.

10-15-2012, 11:57 AM
Thanks for the input guys. I didn't think I'd get much noticeable increase in speed with just exhaust alone but I thought if I could buy them for $700-800 (or even less) it would be worth bolting them on. They sure look a lot better than the old Mercruiser manifolds and it might be a good start.

10-15-2012, 02:15 PM
Good thing is if you do buy a 502 they will fit.