[Aaron75]

I recently had my car stuck on a dyno and noticed that instead of shooting horsepower out to 4800rpm as my engine dyno said, it started dropping around 4200rpm.

The dyno folks said this is probably due to the belt driven fan sitting on the front of my waterpump and showed me a mustang w/ a befor and after that made this a pretty convincing argument. So this lead me to do a bit of research.

I've got a matching numbers '70 w/ a 455 no AC. According to the shop manual all GTOs w/ a 455 HO had a 19" 7 blade fan w/ 2 1/2" pitch. Thus my fan should have a clutch according to their info.

The thing is my engine has a 5 blad 'power flex' fan. Anybody else have a '70 455 w/ this type of fan? Anybody else have a '70 455 w/o AC that has the 7 blade clutch fan?

Thanks.

Aaron

[Held for Ransom]

My 455 has no A/C and a 7 blade clutch fan (sales code 691 and UPC code K02). It was ordered that way.

[Aaron75]

thanks Mr. Ransom.

I guess i'll go to the clutch and see what kind of hp improvements that gives me. Junk yards here i come.

Aaron