To Turbo or to Supercharge, that is the question.

[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.

[HummBebe]

Okie Dokie.....

all time 4 wheel drive. Lets clarify

It's "full time 4 wheel drive"

In 4 high mode the drive train is split 40% front, 60% rear.

In 4 high lock the drive train is split 50-50

In 4 Low lock, again 50-50

When you are in 4 low, (as I was going up the golden stairs ) trying to crawl an uphill obstacle, brake throttle modulation, I was at about 22-2500 rpms before the truck would even move. Thanks to the 4:1 transfer case and the 4.56's.

You are correct in saying that this is done at slow speeds. It is housing flex that causes the failure. However, prop shafts and diveshafts along with carrier brackets have failed as well.

Now a question for you.....do you or are you in possession of a 4WD dyno??

This could be cool

[HummBebe]

PS, those numbers look like the 3.7 not the 3.5. Yes?

[HummBebe]

Originally Posted by b1ownh3

Ok, thanks. I just don't want people to think I am only here pushing our product. We work with many other companies and test product all the time. I bought this truck personally, and hope to work on customizing it so I plan to ask others questions on what they have done.

I would also like to extend to anyone that would be in the Detroit area to come and test drive one of our vehicles with our Rotrex supercharger kits on them. I'm sure the boss wouldn't mind. LOL.

I'll post pictures as the week goes on, and get some dyno numbers up when I get them.

For now we'll consider it R&D

[b1ownh3]

Yeah, I knew it would only be a matter of time before I miss-spoke something. Sorry for using the wrong terminology. You explained it all just like the Hummer dealer. I guess I wasn't paying enough attention. I just wanted to drive it.

Hopefully I'll have better dyno graphs I can post next week so you can see what engine speeds the torque increases, and how much. The graph I have of the 3.5 engine has time across the bottom....not RPM. Hard to read it. Maybe I can get a better graph made up tomorrow and post it.

You are correct, the graph I posted is my '07, which is the 3.7.

[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.....

[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.

[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.

[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

[HummBebe]

Her upgrades so far, Magnaflow exhaust, superchip w/CAI (brought the HP to 350), lowered, and some other cosmetic stuff.

[b1ownh3]

The 15 degrees is the static mounting requirement. We posed the question to them a while back when we started working on a Jeep kit. They told us they see no issue with short term driving at steep angles. I'm sure once the pump is primed there won't be any issues. Now if the vehicle was parked at a 60% grade for hours then started up and driven on that grade I could see some issues. But I would be concerned with the engine having a problem with that also.

Since we are in the process of developing a Jeep kit, I am going to try and push to do some gradability testing of the Rotrex unit. We have specs for many of the OEM's, so we could use that as a start. I'm sure as we get into more and more off-road vehicles this question will come up.

As for power potential of the '07 H3, I'm not sure yet. We usually see over 50% increase in power. The base power was 175, so I would hope for at least 275....at the wheels.

[b1ownh3]

Hey Bebe, have you seen the glass back roof for the new stangs? We have one in a development vehicle. They are made by classic design concepts. They are SWEET! Heres the link....http://www.glassbackroof.com/

[HummBebe]

Too Cool !! Mee likes!

I'm still looking for a new hood too. So many choices it is hard to make a decision. I really need to go to a show and see them all.