how much boost should I be making?

**Tad3d** · January 1st, 2005, 01:47 AM

I've got a sohc (jdm d15b vtec)
with the stock crank, and a 3.8" sc pulley

the SC kit is for a 96+ civic, but I got the 92-95 sc pulley, and I put some washers on the idler pullies.

I've got 2 boost gauges,
one is an old vacuum gauge.. it reads around 6.5psi

another is a spi boost gauge,
it's reading 8psi!

I thought I was supposed to have 6psi though?
the spi does read like 1psi boost when its not even plugged in though.. I dunno.. one of these gauges has to be wrong..

**Tad3d** · January 7th, 2005, 08:09 PM

bump cuz i'm worried about running 8psi on the stock jrsc fueling.

**DC2NR** · January 8th, 2005, 03:29 AM

if it doesnt reset at 0 or close to it, then the guage is not calibrated right. no telling whats the real boost is. borrow someones autometer or any ones guage u know that works. shouldnt be too hard to switch out.

**JRCivic** · January 8th, 2005, 06:43 AM

Obviously, one cannot be registering 1 psi when his car is OFF... so that gauge must be reading at least 1 psi high. This would put the two gauges within 1 psi of each other... and then factor in any one (or more) of the many variables that can actually change one's boost pressure level... crank pulley diameter, cam timing, exhaust size, cat efficiency, header choice, atmospheric conditions, elevation and intake filter location are just a few... and you can easily see why you might be reading 6.5 to 7 psi.

I really wouldn't worry yourself anymore about it. Boost pressure is not the issue... it is blower speed. The blower pulley size of 3.8" is the stock size... and you claim to have the proper crank pulley... so you simply cannot be adding any more air to your D16Z6 than any other "stock" JRSC kit does.