Originally Posted by Formula934

I was expecting the same results when i ordered the 4.5" pulley from you. The 9.7 psi is on the high end, its averaging about 8-8.2 psi @6000 rpm. I figured on the intake and heads bringing down the boost a bit but maybe the cam isnt bleeding off much boost and maybe the exhaust isnt all that efficient. I think if i were to put a cut out on it or step up the headers it may bring down the boost. According to hp tuners, the kpa readings off the map on the back of the intake seem to reflect accurate readings and i am using the boost pid map sensor 2 bar - baro, which is getting a true baro reading i think. I guess it wouldnt hurt to get another reading from a different source though.

Originally Posted by Bob@BruteSpeed

I'd check it with a 2nd boost gauge, that just doesn't seem right. Bob

Originally Posted by ddnspider

That makes me feel better. I only saw about 6 psi with the 4.5" pulley and people were telling me it was low.

Originally Posted by Bob@BruteSpeed

Normally with a bone stock engine with exhaust manifolds, a 4.50 pulley with the 7.65 crank pulley and a D-1SC will get you 9 psi. Add headers and exhaust and it will drop to somewhere around 8 psi. Throw in an aftermarket cam, etc and it drops off from there. Now he is running more compression but I wouldn't expect it to make much of a difference in boost. but Bob

Originally Posted by Formula934

Bob what about the fact that im running the bigger procharger filter and another smaller k&n off the intake hat?

Originally Posted by Bob@BruteSpeed

That really won't affect it at your boost level. Bob

Originally Posted by Formula934

Well i guess the only way to know for sure is an alternate boost gauge and see what it dynos. Im guessing if i cant break 600rwhp its probably not pushing 10 psi of boost.

Originally Posted by corvet786c

I have a 2002 base C5 A4 forged 347 LS6 D1SC (4.38) pulley patriot stage III heads Fast 102 LSXR, LS2 TB with 1 3/4 headers blower cam 3.42 gears.

with bad valve springs and valve float up top, it made 5 lbs of boost on a mustang dyno 430 rwhp 440 tq.

Now on my boost guage with new BTR .660 valve springs, according to my boost guage it's reading 7.5lbs of boost in 93 Hot Florida air.

Don't get hung up on a boost number, if the car is tuned right it will run like a beast.

Hey Bob, how much hp do you think I am making at the wheels, seeing I never re dynoed it?

I am thinking 460rwhp 455 tq.

Originally Posted by Bob@BruteSpeed

460 to 475 rwhp. What is your compression ratio, your #'s are on the low side. Bob

Originally Posted by Formula934

Just confirmed tonight bob was right. Seeing 7 psi consistently now with the clutch replaced.

Originally Posted by Bob@BruteSpeed

That's good to see! Bob

Originally Posted by Formula934

Bob would you venture a guess as to dyno numbers? Given the previous combo 430 rwhp and now putting out 7 psi, what do you think? Dyno is set for saturday.

Originally Posted by ddnspider

I still can't believe it makes that much boost on a 4.5 inch pulley with that heads cam setup.