I have a Commander and an Isspro boost gauge that is tapped into the manifold airhorn. When i put the wood to her the Isspro maxes out at 38psi but the commander goes to 45psi. I can stand seeing 38 but the 45 scares me. I would like to be able to floor it and not worry. I don't do it often but when i do it is becomming a pain to modulate the throttle and try to avoid bark at the same time.
Thanks
Deck

 

Does the isspro have a sender? or is it tied into the manifold sensor?

 

The isspro is not electronic. Just a tube from the airhorn. I am sure someone can correct me if i am wrong. but to the best of my knowlege that is how it is setup.
deck

 

I would say to believe the Isspro then. Make sure the Commander is set up for your truck too. There are different settings for Year Make Model ect. Som eof the older trucks had the MAP sensor starting at 14 PSI (atmospheric pressure) as a base and then boost would build from there. So 20 psi of boost would actuall = 34 on the screen. The commander compensates for all that. Although 45 would not work out for the numbers as I described, I think 45 is as high as the factory Map sensor will read.

 

Thanks vz. I did check the Commander and it is set up for an 06.. THe last think i want is chunks of the Holset blowing apart.
Deck

 

Does it read 45 all the time? Or does it move up and down as the Isspro does, and are the numbers corresponding until they get high?

 

The numbers on the Commander is 1-2psi high down low and 3-4psi high from 20-30 and then at 45psi on the commander the Isspro reads 38.
Deck

 

I'd say it would definately be worth a call to quad and the guys! The can surely fix you right up. Let us know what you find out with them.

 

I ran an outlook monitor and isspro gauges and I think the isspros were more accurate. As far as 45 psi, I ran my stock turbo for 7 months and 15,000 miles at 48 psi and it had no shaft play whatsoever when i changed it out.

 

I will see what i can figure out! One interesting side note, I had to send the Commander in for work. It never read above 38psi before that. When i got it back the first time i let it rip she jumped up to 45 and i about crapped my pants!
Deck

 

I'm not sure I would automatically trust the IssPro over the Commander just because it's an analog gauge. I had a brand new Autometer boost gauge that was defective from the factory. It can happen.

 

44-45 psi is perfectly normal and is accurate with the Standard Module. I would actually be worried if you were only getting 38psi with the module turned on.

I can guarantee you the Commander is accurate.

Not that Isspro is bad but, you have to realize that the intake horn is not a great place to read boost from. The factory MAP sensor reads boost in the actual manifold and not in the horn or stream coming to it.

Where you have it placed might be the whole reason it only reaches 38psi. That or the nylon tubing might be smashed or kinked where the compression fittings go in.

I would say if you do a search that 44-45psi MAX with a box is much more common than 38psi measuring with any gauge.

 

Quad,
Thanks for responding even when you weren't asked. That is why my business is with you! So if i am really seeing 45psi is that safe for my stock turbo. I would like to see 4-5 years out of it. I don't do this all the time but when i do i like to have all i can get. EGT's are fine.
thanks again,
Deck

 

It is not the 45psi that hurts stuff. It is that super fast rise to 45 psi or the super fast drop from 45 psi that will hurt stuff.

The biggest thing I can tell you is that your turbo will last a long time if you don't bark it. When you are at 45 psi roll out of the throttle and make sure you do not abruptly jump off the throttle.

That will keep you safe.

 

Quad,
Just send that guarantee up signed and dated and i will send you a copy back.
Thanks for responding! Is 45 as high as the map sensor reads?

This makes me feel better. Maybe i will tear it up tonight.

Declan