Procharger help...
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Procharger help...
I have a m6 ls3 stock crank pulley, long tubes, tick performance stage 2 blower cam, upgraded valve train, and a p1sc1 with the 4.63 pulley. I read everywhere that you lose boost with upgrades and I seem to only be getting about 3-4lbs. I called procharger and they said a 4.25 pulley would get me to 8lbs but when I read everywhere else I see 4 and smaller. Any suggestions?
Drifting
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A big cam with overlap and long tubes will show a drop in boost but make power. What kind of numbers are you putting down. My LS3 with long tubes, stock cam and 4.25" pulley was putting down 550whp.
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boost is restriction so if you take a completely stock motor with "x.xx" pulley and it makes 10psi then add a cam and longtubes you might lose a few pounds of boost with the same pulley but make more power since your motor is now flowing more air... if you're making ~4psi with a 4.63 then a 4.25 will get you around 8psi just as procharger said... every .1" equals out to about 1psi... every combination is different, different motor, different blower, different mods, air quality, etc, etc, etc, so one pulley is not going to make the same boost on every setup... since you already have a baseline to go by on your car just go by that and don't worry about what everyone else is making with a given pulley
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I put down 549 with slipping belt and 4.63 inch pulley. I got the a&a bracket installed and fixed the slip. But I don't see much more than 3-4 lbs of boost. I ordered a 4 inch pulley but now thinking that might be overkill. Not really sure, but I'd hate to waste 90 bucks if I install it and it's way more than needed.
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Drifting
Joined: May 2008
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From: Jacksonville FL
I put down 549 with slipping belt and 4.63 inch pulley. I got the a&a bracket installed and fixed the slip. But I don't see much more than 3-4 lbs of boost. I ordered a 4 inch pulley but now thinking that might be overkill. Not really sure, but I'd hate to waste 90 bucks if I install it and it's way more than needed.
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I put down 549 with slipping belt and 4.63 inch pulley. I got the a&a bracket installed and fixed the slip. But I don't see much more than 3-4 lbs of boost. I ordered a 4 inch pulley but now thinking that might be overkill. Not really sure, but I'd hate to waste 90 bucks if I install it and it's way more than needed.
The standard 6 rib system can support and easy 750rwhp with the stock tensioner adjusted correctly. (as many have proven)
Actually most people order the kits to make 9psi on stock cars, which makes around 600+ rwhp, and go years without changing the belt. (if ever)
I have a m6 ls3 stock crank pulley, long tubes, tick performance stage 2 blower cam, upgraded valve train, and a p1sc1 with the 4.63 pulley. I read everywhere that you lose boost with upgrades and I seem to only be getting about 3-4lbs. I called procharger and they said a 4.25 pulley would get me to 8lbs but when I read everywhere else I see 4 and smaller. Any suggestions?
The 4.25" pulley would be a good start, plus you can always change your RPM redline a little to make the boost level what you want it. We also make a 4.13" pulley. Its easier to shift 200rpm early, then it is to try and make more boost by spinning the motor further. (Food for thought)
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If you were slipping a belt with a 4.63" pulley, and only making 549rwhp, either it was the wrong size belt, or it wasn't tensioned.
The standard 6 rib system can support and easy 750rwhp with the stock tensioner adjusted correctly. (as many have proven)
Actually most people order the kits to make 9psi on stock cars, which makes around 600+ rwhp, and go years without changing the belt. (if ever)
The cam is where your boost is going, since boost is a measure of restriction. (Cam removes restriction from the motor, by allowing more CFM flow through heads/motor)
The 4.25" pulley would be a good start, plus you can always change your RPM redline a little to make the boost level what you want it. We also make a 4.13" pulley. Its easier to shift 200rpm early, then it is to try and make more boost by spinning the motor further. (Food for thought)
The standard 6 rib system can support and easy 750rwhp with the stock tensioner adjusted correctly. (as many have proven)
Actually most people order the kits to make 9psi on stock cars, which makes around 600+ rwhp, and go years without changing the belt. (if ever)
The cam is where your boost is going, since boost is a measure of restriction. (Cam removes restriction from the motor, by allowing more CFM flow through heads/motor)
The 4.25" pulley would be a good start, plus you can always change your RPM redline a little to make the boost level what you want it. We also make a 4.13" pulley. Its easier to shift 200rpm early, then it is to try and make more boost by spinning the motor further. (Food for thought)
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