To Turbo or to Supercharge, that is the question.

[b1ownh3]

Thanks for all the info. One question. I tried to read through quite a bit of the discussions on the front diff issues, and if I'm understanding it right the problems usually occur at real low speed. I'm a newbee to offroading, but it seems like most people broke the diff when they were stopped by an object and tried to ease over it. Most of which appears to be at pretty low RPM. Am I correct in this assumption? If so, a supercharger should really affect this, as you would still not be in boost, therefore not adding any power or torque. Someone correct me if I'm misunderstanding the situation that appears to be causing the failures.

Thanks.

[stagger_lee]

Originally Posted by b1ownh3

Thanks for all the info. One question. I tried to read through quite a bit of the discussions on the front diff issues, and if I'm understanding it right the problems usually occur at real low speed. I'm a newbee to offroading, but it seems like most people broke the diff when they were stopped by an object and tried to ease over it. Most of which appears to be at pretty low RPM. Am I correct in this assumption? If so, a supercharger should really affect this, as you would still not be in boost, therefore not adding any power or torque. Someone correct me if I'm misunderstanding the situation that appears to be causing the failures.

Thanks.

You are pretty much correct. Although with the 4.1 and 4.56 gears we can run 2-5 mph and be at 15-2200 Rpms and we would definately be boosting there, right? Thus adding torque to wheels and stress on diff. Does that sound right? I am not familiar how this supercharger works. I assume its belt driven and boosts all the way through the power band. Where does it hit max boost and what is it boosting at, 10 PSI max? I can only attest to muscle cars, but my pops has a blown Dart. My thoughts were this, and the difference in throttle response is night and day now we are blown. Now it is very jumpy, and when rockcrawling we dont want jumpy. We want it to be smooth and slow. Jumpy causes axle hop and breakage. I am simply speculating at this point because I have not been rockcrawling in a rig that was supercharged, just taking my knowledge of both and applying it.

[b1ownh3]

Ok. Step one has just been completed. We have baselined the 2007 manual trans H3. I have attached the dyno sheet. Little depressing, but we have a long ways to go. This is in all time 4 wheel drive, so it is at all the tires. We have an all wheel drive chassis dyno.

[stagger_lee]

At least we have nice even torque distribution through the power curve. Not too impressive though. Thats why we have big gears, offset tthe lack of power.

[ChevyHighPerformance]

Not bad. The weight on the dyno sheet should be closer to 5000 lb. This shows the drivetrain efficiency to be about 72%. You can see the two humps in the torque curve from the VVT. Keep dynoing in 3rd. You should see better numbers in 4th gear but you'll hit the speed limiter with the stock programming.

[wpage]

Too bad GM wont do some of this homework

[stagger_lee]

Maybe they did and didnt share. I cant wait to see the outcome of this whole thing. It just might prove to be a worth while power upgrade for us, if done right and tested significantly.

[b1ownh3]

Most people relate supercharger output to that of a roots style (like a magnuson or a Roush). The supercharger we use is a centrifugal style (similar to a procharger). With a roots style, you tend to make high levels of boost down low, which make for great low-end torque. However, they usually run out of air at higher RPM's and fall off. With the centrifugal style, you don't usually make boost till about 2500 rpm (depends on engine rpm and max boost) so they usually make better power up top. Now if you are concerned about over-loading the driveline at low rpm (15-2200), I don't see any added stress from this perticular supercharger. We have a system on a 2006 H3 development vehicle that we have been driving around. It has pretty much only been driven on the road, so I can't give any feedback to how it does in the crazy situations some of you are looking to put one through . I have a dyno sheet on it, but it didn't print very clear so it doesn't show up when I try to scan it. Here is a summary:

Max Power - 242hp @ 5800 rpm
Max torque - 226 ft-lbs from about 3200-5000 rpm
Max boost - 7.78

These numbers are pretty conservative for a stock engine. Of course you can push the boost for more power, but at some point I would worry about the pistons. I'm going to contact some of my guys at GM, as I know they have pushed this engine with both turbos and superchargers until they broke. I'm curious as to at what level they broke, and where they broke (pretty sure it would be the pistons). As I get info I will pass it along.

[stagger_lee]

Bebes.

Originally Posted by b1ownh3

Ok. Step one has just been completed. We have baselined the 2007 manual trans H3. I have attached the dyno sheet. Little depressing, but we have a long ways to go. This is in all time 4 wheel drive, so it is at all the tires. We have an all wheel drive chassis dyno.

Dont you think a supercharger would be a nice addition to your rig?

[HummBebe]

I can't afford 2, and teh Pony gets hers first

[deserth3]

On your technical specs it mentions a flat spot on the unit must be installed down and within +or- 15 deg from horizontal. I assume this is for oil flow and cooling.
When offroading it is possible that the vehicle will be more than 15 degrees off horizontal. What is the potential for supercharger failure?
How long will it last in this condition?
If it does fail would it be considered an out of warenty failure?

[HummBebe]

Great questions.....

[evldave]

Originally Posted by deserth3

On your technical specs it mentions a flat spot on the unit must be installed down and within +or- 15 deg from horizontal. I assume this is for oil flow and cooling.
When offroading it is possible that the vehicle will be more than 15 degrees off horizontal. What is the potential for supercharger failure?
How long will it last in this condition?
If it does fail would it be considered an out of warenty failure?

c'mon no one actually gets their H3 more than 15 degrees from horizontal! Hummer uses a special oil pickup on the I-5 as a poser mod, not one that's actually needed. I just measured and I only get 3-4 degrees going over curbs - that's the worst offroading I'd ever want to subject my H3 to in real-life situations.

[fourfourto]

Originally Posted by HummBebe

I can't afford 2, and teh Pony gets hers first

How much power you going to get on the 3.(and how many front differentials will you have to replace. )
The stang will kick a$$ with a supercharger

Bebe how come there are no pics or videos of the stang.
Lets see some holeshots ,flatspins and donuts


Ill post some of the 442 soon.

What about that 'stang? Details/pics maybe.

[HummBebe]

Spends most of her time in the garage. The H3 has 48K, the pony 8K, bought them within about 2 weeks of eachother.

I'll see if I can find some pics.


Edit: Found one