kongdong

I got a procharger (P-1sc stage 2 kit) installed and for some reason after I got the car dynoed the car was only using 7-8lbs of boost when I'm running on an 10lb pulley. Can anyone figure out why? The only mods I have are LT headers, high flow X-pipe, and Borla mufflers. Thanks everyone.

cobra dreamer

what size pu;;ey are you running ?
i have a 3.20 making 10psi

vanquish

Every car is different but you could be loosing boost from the longtubes you have. If that kit is intercooled there is another reason why boost is being lost.

kongdong

The kit is intercooled. It's a 3-row and why would the long tubes be affecting my boost? I was told they provide extra low end torque when you go with a supercharger.

Sxynerd

You're not "Loosing" boost, Your engine is running more efficient. Boost is a measure of restriction. Your engine is using the air flow and the numbers are showing it. When I added heads and LT's I lost 6-7lbs of boost

kongdong

Then how comes I'm not using all 10lbs?

PRO50SC

I will def disagree on the above statements.

If you are running stock heads, that could be the problem. Also make sure ALL the connections are tight, boost can be lost through the slightest small opening that might otherwise be undetected. Also, you will only see maximum boost at the very top of your rpm band. Pay closer attention to that next time you are there.

I run that same kit on my car. It was a 9psi pulley that I changed to a 14 so I could hit boost faster from running a smaller pulley.

kongdong

All the connections are tight. I double checked them. I am running stock heads though. Is that possibly the issue?

vanquish

What do you mean? How are stock heads a "problem"? If anything he would be seeing less boost with aftermarket cylinder heads. I'm sure procharger doesn't assume everyone has aftermarket heads when they claim some kind of baseline estimate in boost for whatever kit they make. In fact, I bet procharger, vortech, KB, etc. state the psi of their kit based on a stock car.

I have a supposed 10 psi pulley (3.33") on my car and I see 10 psi with a Vortech aftercooler.

If I had longtubes, aftermarket heads, aftermarket camshafts, and/or a conventional intercooler I absolutely wouldn't see 10 psi.


I shouldn't have said "lost" boost before I understand that it really isn't lost just easy to say in conversation.

Sxynerd

The bold underline section is the money maker to your question.

Think of it like as a Freeway. 5 lanes vs. 2 lanes. Lets say 10,000 cars are trying get to work during morning rush hour traffic with a 1 hour commute. The cars represent "Air", the Fwy represent "Pump that is your engine" and the lanes Represents the "Path". And the Time (1 hour) represents the boost gauge.

With 2 lanes the 10,000 cars are bunched up trying to fight for position to move forward and it takes them the 1hour they expected. (You expected 10lbs of boost)

Now, lets replace that 2 lane with a 5 lanes fwy. There is less restriction and the flow of cars takes less time, so the 1 hour commute now only takes 45 minutes. (you have LT's and are making less boost)


Adding LT's and a free flowing exhaust helps turn a 2 lane fwy into a 5 lane decreasing the time (Boost) all the while STILL moving the 10,000 cars. You did NOT "Loose" boost, your engine is still pumping the same amount of air (Cars) but it's doing it more efficiently. (5 lanes vs. 2 lanes)