boost gauge vs vacuum/boost gauge

[corsair231]

Po-ta-to, po-tat-o. It is personal preference. I've had both and prefer just boost. The two things to consider are: just boost equals a larger scale size and easier to read but no vac., combo equals the added benefit of a vac reading but a smaller scale size and with a smaller scale any error will be off more than on a larger scale (1/8 inch on a small scale may equal 3 lbs but only equal 1 lb on a large scale). Of course gauge quality, range, and size all play factors in that.

 

[Steve]

I was faced with the same decsion years ago on my first GN. A buddy had a VDO 0-30 boost gauge with no vacuum for a bargain but I was torn because I really wanted a boost/vacuum gauge. I ended buying the bargain VDO and regretting it and then going back and buying the boost/vacuum gauage and have had the boost/vacuum set up in every other TB I have owned since. I like to have vacuum for lauching purposes also. When I am at the track and the track is not hooking well or I am on street tires its easier to build the boost to the proper level when I can see the vacuum also. WHen I tried to leave the line at say 2 psi(which is a 1.65 60' in my car and works well on my Nitto DR street tires) or so with the VDO I would get on the brakes and give it some throttle and I had no idea where I was until the boost shoot right past 2 psi then I had to back off the throttle and go back and try to find the sweet spot but with the vacuum /boost set up you can see the needle move all of the way from idle to the boost you desire and its easier to hit the target the first time when you see it coming!

 

[toofastforyou]

I'm replacing all my gauges very soon (probably this week) and these are what I ordered:

1° Auto Meter 2/16" Carbon Fiber boost gauge (pt# 4704)
2° Auto Meter 2/16" Carbon Fiber water temperature gauge (pt#4737)
3° Auto Meter 2/16" Carbon Fiber oil pressure gauge (pt#4727)

That's all I need...

Claude. :wink:

 

[turbofrank]

vacuum can give indication of bad valves, valve train, headgasket or vacuum leak.

 

[GNVYUS 1]

Here's a gauge that's pretty useful if you're past 30psi sometimes
Stewart Warner 114542 - Stewart Warner Maximum Performance Series Analog Gauges - Overview - SummitRacing.com

Here's one for the ricer in you
Stewart Warner 114524 - Stewart Warner Maximum Performance Series Analog Gauges - Overview - SummitRacing.com