PDA

View Full Version : Boost Gauge Ratings?



ndamico
06-13-2002, 22:58
Alright,

finally time to bite the bullet on the gauges. going to go with the isspro pyro/boost pillar mount. my LAST (right) question is should i get the 30 PSI or the 40 PSI gauge? the 40 PSI says "manifold pressure" instead of "turbo boost". isn't that the same thing? will my dmax potentially ever get over 30 PSI with upgrades that come out down the road? my buddies cummins peaks around 31, but that's a dodge..

and odoh,

i'll be doing the install at my buddie's BMW/Porsche shop, so we can install yours along with my friends once i've jacked mine up and learned how to do it right!


thanks as always! ;) ;)

Kennedy
06-14-2002, 09:24
Unless you are going to mega bomb it, I would stick with 30 psi. I hit 26psi peak on my SPA measured post intercooler.

Future plans include an adjustable wastegate actuator to test the results of creeping the boost up towards 30ish. Blocking the wastegate hose has not yet (at least on mine) shown any improvement in performance, BUT this setup produces the maximum in pre-turbo back psi.

I may change my position when I install a modified turbo, but unless you plan to step it up to that level, I'd be satisfied with the 30psi as the resolurtion will be finer due to using more of the gauge's dial area.

SoCalDieselNewbie
06-14-2002, 12:26
Mr. Kennedy,

My understanding of the need to monitor boost psi is not for excessive peak boost but rather for insufficient peak boost.

In other words, when the boost psi should be high, it is actually low... thus creating a higher EGT than expected under that load scenario.

But heck all this turbo & diesel stuff in land vehicles is new to me. Hence the NEWBIE in my handle.

If you wanna talk Yanmar Marine motors, drag bikes or big block chevy; I might be of some use. :D


ndamico,

By the way, you think that we are a sick crowd?

Here is a buddy's shop...

http://www.rbtechla.com

He'll be doing my stereo and multimedia but what he normally does is custom work and performance parts for Mercedes Benz, BMW, Ferrari, Porsche & Bentley.

It is scary the # of Mercedes Benzs that I have seen over at his shop, with less that 10 miles on the odometer, that are pieces because the customer wants new suspension, brakes, wheels, exhaust and major motor mods. I guess it is only money.

Anyway, as Dr. Dre said to his buddy, while sitting in the lobby of the shop waiting for his buddy's Ferrari Spider to be done, "you may think you're a playa with your spider but if you ain't got a Bentley, you ain't even in the game."

JEBar
06-18-2002, 20:25
Agree with JK...30 pound gauge is fine unless you plan rocket level modifications :D

Nevada Hauler
07-03-2002, 01:22
ndamico,
Hope this isn't too late. Manifold pressure and boost are not the the same! MP measures ambient pressure plus boost (14.9 psi at sea level with the engine off), boost measures pressure above ambient ( 0 psi at any altitude with the engine off). MP gives you the total amount of air in the manifold, which is the number that is most important. You can approximate the ambient pressure by adjusting by 1 psi for every 2,000 feet above sealevel, Soooo, I would go with the 30psi boost gauge because the 40 psi manifold presure gauge will only show you 25psi of boost at sealevel. You would have to go to about 10,000 feet above sealevel to see 25psi of boost with this gauge.