Boost gauge, need help ASAP!!

[Chris_H]

Ok I have tonight and tomorrow to get this hooked up. I am not sure how to hook up this gauge though. I have some vaccum line, but I don't see how it is supposed to stick to the back of the gauge. Seems the connectors they gave me with this autometer gauge won't hold the line into the back of the gauge. Where does the gauge hook into in the engine compartment?? I have to have this done by tomorrow night at the latest since I am heading out of town right after work on Friday for the weekend. I have school tonight, work tomorrow and school tomorrow night, so I am limited in time. I appreciate any help you guys can give me.

Chris

[RED92LX50]

The tubing should connect to the back of the gauge with a brass crush sleeve and a brass screw-on collar. you feed the tube through the screw-on collar, and then slide the crush sleeve over the tubing. Leave about 1/4" or less of tubing sticking out past the crush sleeve, then insert the tubing/crush sleeve into the gauge hole and then tighten the screw-on collar over the crush sleeve. Don't tighten it too much or you will cut into the palstic tubing.

On the other end, just connect the tubing to an open port on the Vac tree on your firewall. remove the rubber cap that is there now, and then slide some small diameter rubber tubing over the open port, then insert the vacuum line tubing into the rubber tube.

[exgmguy]

That's right.

Let us know how much boost you are seeing with the Novi. I have the Novi 1000 as well and I see 6 psi @ 6000 RPM.I did just order a smaller pulley from ASP though.

I am also interested in seeing blower dyno numbers for your car. My car made 309 RWHP on motor, I hope for 425-450 RWHP once the new pulley is on, and it is tuned.

rob Shackleton

[Chris_H]

Well I got the gauge working today. Thanks for the help. The problem is that I am up at 3900 ft and of course there is no air up here. I haven't fully ran the car with the gauge, but I saw all of 2psi when I did. I will run it hard tonight on the way home from school and see what I can come up with. I am not expecting more than 2psi though. I will be in Oklahoma tomorrow night, and my parents are are 1000ft, so I am hoping for at least 4psi. I am kind of dissapointed, but what can I do other than move to a lower elevation. Thanks again for the help. I will let you guys know when I get back monday.

Chris

[Mach 1]

If the air is being forced into the engine via blower, is elevation much of a factor if at all?

[PKRWUD]

Yes, it does make a difference. In fact, there is a formula (of course) to predict how much the boost will fall off:

(Alititude / 1000) x .2 = the amount of boost you will lose.

For example, at 3900':

3900 / 1000 = 3.9

3.9 x .2 = .78 psi

So, at 3900', you should expect the boost to be .78 psi lower than it would be at sea level.

Take care,
-Chris

[Chris_H]

Ok, well Chris seems to have hit it on the head. I took the car out on the highway last night with my wife and had her watch the gauge while I took off. Right about 6000rpm, and actually off the rev limiter (oops) I am making 4psi. That last pound was a pain to get, but right around 6000 I finally get it. To be honest I did't think I would make that much boost. But then again, I am usually shifting around 5200-5500 at the track. Wonder if this means I should run her up to 6000 everytime I run it. I am taking an 1100 mile round trip this weekend, so I will let you know the difference between 3900ft and a 1000ft. Can;t wait to see how she runs down there with the elevation and 93 octane which doesn't exist around here. Everybody have a safe weekend. Thanks again for everybody's help.

Chris