For those with superchargers...Need technical advice

[OrangeCrush]

Well, finally installed the supercharger last weekend. I spent this last week buttoning everything up. I got to drive it home Friday and because I don't have an air/fuel ratio gauge, I didn't want to beat on it.

The tuning came from Allen Nelson so I'm pretty confident it's setup correctly. i'm going to make an appt this week to put it on a dyno just to make sure everything is okay.

During this weekend, I did punch it a couple of times out of the hole and within the first 2-3K rpms, the truck stuttered like the rev limiter was kicking in. I thought at first the belt was slipping but it's tight.

Anyone have any suggestions?

Thanks,

Mark

[HUMMERcustoms.com/TAZ]

Hey Orange,

I know this seems like some obvious questions:

What psi injectors did you use?

Did you do a fuel pump upgrade or use a Keene Bell boost a pump?

Fuel filters changed?

Air filter clean?

Double check with Allen on your situation as it sounds like timing may be off or something in setup is out of sinc.

Did You pop a check engine light?
Once when I was messing around I put my 10lb. pulley on with the fresh load of the kit tune and it ran great the first WOT run then popped a check engine light and went to a more stock type running situation but, more powerful still. I pulled the kit tune replacing with stock and before running I put the kit tune back in fresh the second time. The rig launched great again until I let off and just like the first time reduced power and check engine light. The timing was retarded for sure of which was expected since I was experimenting. I was just surprised the rig launched like a rocket after removing the kit tune and putting it back in fresh.

Not much help I know but I would contact Allen soon.

TAZ

[OrangeCrush]

Originally Posted by HUMMERcustoms.com/TAZ

Hey Orange,

I know this seems like some obvious questions:

What psi injectors did you use?

I bought the supercharger used and the fuel injectors were already installed. I may need to double check it but I can't imagine someone selling the whole setup and then putting in the stock injectors... good thing to check though.

Did you do a fuel pump upgrade or use a Keene Bell boost a pump?

Upgraded in-line fuel pump.

Fuel filters changed?

Yup

Air filter clean?

Yup

Did You pop a check engine light?

No, no lights. I cleared the couple of codes I had when I first got it fired up and the only one I couldn't (needed a tech II) was the crank shaft position learning code. Got that done by a friend that works at a dealership.

Not much help

Gave me some insightful things to check. Was much help.

I know but I would contact Allen soon.

Definitely today.

TAZ

Thanks bud, much appreciated.

[H2 Bill]

Hopefully Nelson eliminated the torque management when he did the tune.

[OrangeCrush]

Just a quick update.

I haven't been able to get in contact with Nelson yet but Tim did notice something that seemed to make a difference.

The supercharger was used and came off a Silverado. Apparently the Silverado 6.0 has a hose that connects both fuel rails in the front that the H2 doesn't use.

Point is, Tim and I removed it and the truck seems to run fine. No stuttering, no nothing.

I'm still going to put it on the dyno just to make sure the air/fuel numbers are correct.

The other thing is, I'm not sure how much "learning" the computer needs to do since it is a "new" computer.

I was bad tonight though. Some punk kid was in front of me at a major intersection tonight on the way home.

When the light turned green, he nailed it. He took off and I thought how funny would it be if I could catch him. (by this point, he had about 7-8 car headstart)

Not only did I nearly mow him down, I slungshot around him so fast, I'm sure he felt a vacuum when I passed him.

Damn truck runs good.... I'm impressed.

Of course, my mileage still sucks but hey... it runs good.

Mark

[HUMMERcustoms.com/TAZ]

Hey Orange,

We are going to get mostly the same milage with or without the supercharger
We may as well have some fun with the power and speed increase along with better towing capabilities.

Good Luck and have fun!!!!

Oh, the extra hose sounds like it was letting fuel bypass easily and allowing You to hold to low of fuel pressure. I run a fuel pressure and boost gauge all the time. I have the a/f that i can turn off and on when i need it. Plus once the new screen and computer is finished installing by Dragon I'm supposed to be able to keep my a/f scan up on screen after music or cd is playing so I can watch a/f in wideband while scanning what the rig is doing all the time to fine tune tuning all the time. The a/f I turn off is run off the factory oxygen sensors that are fairly reliable but, just not for tuning.

If fuel injectors are say 48psi then You can run gauge and it is just something else to help You diagnose if need be. With Keene Bell boost a pump I left off the extra fuel pump and I can fine tune my a/f by turning the knob up and down with a range on these injectors of about 45 to 54psi.

Orange Enjoy Your were patient a long time waiting to get the SC on. I hope You really have fun but, be safe. Hey it is cool not be that turtle on the road anymore isn't that right? Just imagine what it is like at 10lbs. of boost and I'm just dreaming of what it will be like at 15, 16, or 18 pounds of boost.

I really can't wait to begin slowly working my way up. With the computer though I can tune the rig down making it better on the street by just picking the tune of the pulley i change to stored and unload the one in H2 computer and flash it with the next one. I'm excited about seeing how flexible I can make the tunes with different tuning using water.met injection etc.

Anyone who happens to go to using the HPTUNERS software I will be, once tested and tried, upload them to HPTUNERS site in an area where tuners can place tunes for others to download and use. When I get one up I will let all know so anyone can go and get it.

TAZ

[rocketw19]

Originally Posted by OrangeCrush

Just a quick update.

I haven't been able to get in contact with Nelson yet but Tim did notice something that seemed to make a difference.

The supercharger was used and came off a Silverado. Apparently the Silverado 6.0 has a hose that connects both fuel rails in the front that the H2 doesn't use.

Point is, Tim and I removed it and the truck seems to run fine. No stuttering, no nothing.

I'm still going to put it on the dyno just to make sure the air/fuel numbers are correct.

The other thing is, I'm not sure how much "learning" the computer needs to do since it is a "new" computer.

I was bad tonight though. Some punk kid was in front of me at a major intersection tonight on the way home.

When the light turned green, he nailed it. He took off and I thought how funny would it be if I could catch him. (by this point, he had about 7-8 car headstart)

Not only did I nearly mow him down, I slungshot around him so fast, I'm sure he felt a vacuum when I passed him.

Damn truck runs good.... I'm impressed.

Of course, my mileage still sucks but hey... it runs good.

Mark

glad you got that fixed bro! what kind of tune did you get from nelson? did you get a pully also? i have been thinking of a tune also but not sure its worth it.