Changing pulley/ boost gain?

[dvs bullet]

Let me retract my previous statement, my impeller is a pinkish color. Not sure what I was thinking but it's currently off car so I took a look last night. Sorry for the confusion...Attachment 1921

cool! Thx for the pics, i guess mine is just a stock impeller :(

[Michael]

Don't be so quick to say your impeller is stock just because it isn't pink. Color shouldn't be used as a basis for determining whether or not the impeller in your SN is an HO or stock; I've seen a few "as cast" grey HO impellers. Looking at the impeller through the intake volute won't help either. The best way to tell is to remove the impeller cover and inspect the impeller first hand.

For example, here's a couple of photos taken from another discussion thread here (courtesy of SCH member winfred) showing an HO impeller in an SN. The first image shows the impeller inside the blower; ignoring color, it's difficult to tell whether or not it's an HO impeller. The second photo shows the impeller sans cover, and it's far easier to see that it is indeed an HO (with it's slightly cupped impeller vanes).

If you don't want to (or can't) remove the cover, you can also run your finger along any of the vanes to feel for the slight cupping along the intake/leading edge. If you feel the cupped edge, then it's pretty safe to say you have an HO impeller.

[Duke]

My impeller vanes are not curved at all and it is grey and it is stock just how it came from summit racing back in 2000. all by the way stock crank pulleys on the 87-93 5.0 mustangs are 7'' go to your local ford dealer and ask!!

[Duke]

i also run 100 octane gas in my car so no need for boost retard box.

[dvs bullet]

Don't be so quick to say your impeller is stock just because it isn't pink. Color shouldn't be used as a basis for determining whether or not the impeller in your SN is an HO or stock; I've seen a few "as cast" grey HO impellers. Looking at the impeller through the intake volute won't help either. The best way to tell is to remove the impeller cover and inspect the impeller first hand.

For example, here's a couple of photos taken from another discussion thread here (courtesy of SCH member winfred) showing an HO impeller in an SN. The first image shows the impeller inside the blower; ignoring color, it's difficult to tell whether or not it's an HO impeller. The second photo shows the impeller sans cover, and it's far easier to see that it is indeed an HO (with it's slightly cupped impeller vanes).

If you don't want to (or can't) remove the cover, you can also run your finger along any of the vanes to feel for the slight cupping along the intake/leading edge. If you feel the cupped edge, then it's pretty safe to say you have an HO impeller.

Thanks soo much for the info!! I felt for that cupped edge like you said, sure enough it is cupped woohoo!!! Looks like I have one of those cast color HO impellers! On with the build I go, thx everyone!

[aseecobra]

Back in 1997 I had Paxton install the HO impeller into a SN-92 I had and it was grey. I also had a new SN-93 from that year that had a grey impeller.

Chris