xr4x4ti
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I have been playing around with my 2017 Odin Supercharged AWD Mustang and stumbled into something weird.
A little background, I had to replace the short block over the winter and I installed the 9.5:1 CR Ford Gen 3 Aluminator short block. When I got the car running in the spring I swapped the stock 3.5in pulley the Odin comes with for a 3.3in pulley. The 3.3in pulley resulted in about 10-11psi of boost. After a few break in miles I swapped the 3.3in for a 2.9in pulley and all was well. I got about 13-14psi boost and the car likes 18-19+ deg of timing on 93 octane.
Now we get to this weekend and with the low compression I am confident I can run even more boost on pump gas and I swap the 2.9 for a 2.7in Griptec pulley with a shorter Goodyear belt. The 2.7 pulley results in about 15-16+psi but the belt with the current setup is not happy. It is noisy when it is first started up, squealing, etc. But after it warms up it seems to calm down and at least the squealing goes away even though it is still louder than the 2.9in "smooth" pulley.
Here is the thing, with the 2.7in pulley the car is pulling timing like crazy. I have it setup to allow up to 10deg of retard and it will max out sometimes, but 4-6 deg is pretty common. Even if you back pedal and hold the boost to 12-13psi, it still is pulling timing.
Thinking maybe I had a bad tank of gas, I put almost a full bottle of Torco Octane booster in the tank, no difference, pulls tons of timing.
So I go back to baseline and reinstall the 2.9in pulley and Gates belt and flog the Sh%t out of it. Just a few spots where it pulls a degree or two on tip in an then it ADDS timing under high boost as the RPM climbs.
It is not remotely conclusive, but my only thought is that the belt/pulley noise was causing false knock?
If that is true, are Griptec pulleys normally noisy? Am a reaching the end of a 6 rib pulley system? Should I try a Gates belt? Slightly smaller belt? VMP does sell a higher load tensioner I could swap in. I don't want to upgrade to a 8 rib system this season.
Thoughts?
A little background, I had to replace the short block over the winter and I installed the 9.5:1 CR Ford Gen 3 Aluminator short block. When I got the car running in the spring I swapped the stock 3.5in pulley the Odin comes with for a 3.3in pulley. The 3.3in pulley resulted in about 10-11psi of boost. After a few break in miles I swapped the 3.3in for a 2.9in pulley and all was well. I got about 13-14psi boost and the car likes 18-19+ deg of timing on 93 octane.
Now we get to this weekend and with the low compression I am confident I can run even more boost on pump gas and I swap the 2.9 for a 2.7in Griptec pulley with a shorter Goodyear belt. The 2.7 pulley results in about 15-16+psi but the belt with the current setup is not happy. It is noisy when it is first started up, squealing, etc. But after it warms up it seems to calm down and at least the squealing goes away even though it is still louder than the 2.9in "smooth" pulley.
Here is the thing, with the 2.7in pulley the car is pulling timing like crazy. I have it setup to allow up to 10deg of retard and it will max out sometimes, but 4-6 deg is pretty common. Even if you back pedal and hold the boost to 12-13psi, it still is pulling timing.
Thinking maybe I had a bad tank of gas, I put almost a full bottle of Torco Octane booster in the tank, no difference, pulls tons of timing.
So I go back to baseline and reinstall the 2.9in pulley and Gates belt and flog the Sh%t out of it. Just a few spots where it pulls a degree or two on tip in an then it ADDS timing under high boost as the RPM climbs.
It is not remotely conclusive, but my only thought is that the belt/pulley noise was causing false knock?
If that is true, are Griptec pulleys normally noisy? Am a reaching the end of a 6 rib pulley system? Should I try a Gates belt? Slightly smaller belt? VMP does sell a higher load tensioner I could swap in. I don't want to upgrade to a 8 rib system this season.
Thoughts?
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