[tull9643]

I have a 2007 GEP turbo 6.5L I built a turbocharger with an extended billet compressor wheel.
I put a boost gauge on it and am rather disappointed with what I am seeing, but also a little confused at what I am seeing.
I am running around 7psi at 75mph and 2200 rpm, if I lift my foot and then get back into it it will jump to 10psi for just a second then drops back to 7 psi.
another thing is while accelerating the boost drops off as the rpm increases,,,is this normal?
I guess I will try to build an adjustable waste gate controller, the HMMWV just has a spring loaded waste gate as they do not have vacuum, but I have not seen an aftermarket manual controller for the GM-7 center mount.
That should not be too hard to build...
THANKS!!

 

[OkDually]

I have a 2007 GEP turbo 6.5L I built a turbocharger with an extended billet compressor wheel.
I put a boost gauge on it and am rather disappointed with what I am seeing, but also a little confused at what I am seeing.
I am running around 7psi at 75mph and 2200 rpm, if I lift my foot and then get back into it it will jump to 10psi for just a second then drops back to 7 psi.
another thing is while accelerating the boost drops off as the rpm increases,,,is this normal?
I guess I will try to build an adjustable waste gate controller, the HMMWV just has a spring loaded waste gate as they do not have vacuum, but I have not seen an aftermarket manual controller for the GM-7 center mount.
That should not be too hard to build...
THANKS!!

Normal...
Boost is not a constant. It is commanded by the ECM when needed.

 

[tull9643]

No ECM all mechanical and only a spring loaded waste gate controller

 

[Keith_J]

Exhaust volume (RPM X boost) and EGT drives the turbine. Since you have an all mechanical setup, this could be waste gate opening by back pressure. As you didn't state engine speed, also consider the injection pump starts limiting fuel above 3400 RPM.

Measure EGT and exhaust back pressure. Plus engine tach.

 

[Tommygunner]

This may work
Center mount mechanical Turbo WG control for H1 & Hummer. From a site supporting vendor.

BD-Power 1059651 Turbo Boost Control Wastegate

Check out the deal on BD-Power 1059651 Turbo Boost Control Wastegate at Xtreme Diesel Performance

www.xtremediesel.com

Also make sure your exhaust is not restricted as posted above. If your H1 has a catalytic convertor, it is most likely plugged.

 

[tull9643]

Never drive it over 3K, don't need to as I have a 6L80 transmission, I am going to try building manually adjusted waste gate controller, I saw a youtube vid, the guy was running the same setup and boost as I am until he installed a manually controlled (screw adjust) waste gate controller, seems the military did not have much use for boost.
BTW he was running 17 PSI (had the same aftermarket compressor wheel I have) I have no need for that much boost but his EGTs came down with the increased boost, he also turned up his pump 1/3 turn.
I asked KBD about a boost controller and they said it was too easy to mod a stock spring type controller which I have several of.

 

[Tommygunner]

I asked KBD about a boost controller and they said it was too easy to mod a stock spring type controller which I have several of.

Yeah 140 is a lot of coin to spend. Here is a thread to mod your stock mechanical waste gate control for next to nothing. It uses the side mount controller but yours should be similar

Home made boost controller

This was way to easy not to post and a lot cheaper then paying $110 bucks for one. Before we started the truck was peaking at about 6 psi on the street and only holding maybe 4.5-5 psi. We started by cutting the housing where it bends over to brake it open. As you can the inside is very...

www.dieselplace.com

 

[tull9643]

Yeah 140 is a lot of coin to spend. Here is a thread to mod your stock mechanical waste gate control for next to nothing. It uses the side mount controller but yours should be similar

Home made boost controller

This was way to easy not to post and a lot cheaper then paying $110 bucks for one. Before we started the truck was peaking at about 6 psi on the street and only holding maybe 4.5-5 psi. We started by cutting the housing where it bends over to brake it open. As you can the inside is very...

www.dieselplace.com

Thanks!!