3800 Pulley system or no pulley system..?

[imported_Theautoguy]

OK, I used the last couple of trips to the track to focus on the next little mod to the Regal. I was eyeing a pulley system with a stock-sized pulley, a 3.4 pulley and 3.25 pulley, I'm currently running a 3.4. I want the versatility of changing from a daily driven 3.4 to a track 3.25 to a more Winter friendly stock size for the wife to drive it. I recorded knock and boost number for the last few runs and I'm observing a burp or two of .5-2.0 degrees of knock retard near the top end. With that, I'd feel comfortable to go to a 3.25 pulley at the track...but...I'm also reading a peak of 12 pounds of boost too! I'm hesitant on running a smaller pulley and risk boost stacking and a potential gasket failure. I do not want to dump headers or an I/C in this thing anytime soon.

I suppose what I'm asking advice on is with a knock count of 0, a knock retard under 2 in tiny little burps and the boost regularly peaking at 12 pounds around 6000 RPM, can I run a 3.25? If so, should I shift before 6000 RPM and before the peak boost levels, perhaps at 5800 RPM? Am I going to stack boost to the point of failures or ???

In addition to the 3.4 pulley, my pertinant mods are;

U-bend delete
Full 3" exhaust
MSP CAI
180 degree thermostat
DHP

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[Mike K]

Keep away from the 3.25 unless you plan on running race gas with it. If you're running any knock with an existing pulley, you're not yet ready to drop down another size, at least not in my opinion. In the winter you might be able to get away with running a 3.3, perhaps a 3.25, but I wouldn't push it.

Would the wallet allow rockers and a Modular system? That would set you up quite nicely.

 

[J.E.T.]

Regardless of your decision, you definately need a modular pulley system. It's just soooo much more convenient and versatile!

J.E.T.