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h2co-pilot
06-27-2007, 12:15 PM
http://www.detnews.com/apps/pbcs.dll/article?AID=/20070627/AUTO03/706270330/1149


.... they took a standard Hummer H3 and did some modifications that can serve as a template for anyone interested in taking his or her H3 more toward the extreme of off-roading.

Two things the engineers needed were: increased ground clearance and clearance to mount a set of LT315/75R16 tires that are 35 inches in diameter. The standard H3 comes on 32-inch tires.

Going to 35-inch tires was vital to the work the engineers needed to do, said Todd Hubbard, H3 vehicle dynamics engineer.

Hubbard added that 35-inch tires also are something that serious off-roading H3 owners will want to consider. However, he suggested those owners not go to the extremes the engineering team did. Instead, he said all they really need to do is to do a one-inch body lift, which can be done with a dozen one-inch spacers and longer bolts.

He noted that the H3 brush guard can be adjusted to hide any resulting gap at the front of the vehicle and that the H3 fan shroud can be rotated to prevent the possibility of rubbing.

Hubbard said this setup is practical and maintains a lower center of gravity than the more extreme measures on the engineering truck, which features a four-inch Rancho front suspension lift (see www.gorancho.com (http://www.gorancho.com/)).

After installing the kit, GM engineers and technicians at the Milford Proving Grounds modified the H3's rear suspension -- inverting some factory parts and fabricating others -- to raise the back end level with the front.

They also installed an electrically locking front differential, which is not yet available on the H3, and the wheel flares that are standard on the H3 in some overseas markets (those flares can be ordered through any Hummer dealership, Hubbard added).

Those flares were needed to fully cover the larger tires, which the engineers mounted on two-piece bead-lock wheels that were originally built for use by the Border Patrol. Off-roads often need to air-down their tires for enhanced traction and the bead lock setup means tires can be run at zero air pressure if needed. However, the wheels the engineers selected had to be modified to fit the H3 lug pattern and to provide the proper offset. Hubbard suggested that H3 owners should be able to find wheels for their 35-inch tires through standard off-road aftermarket suppliers.

The result with either with the simple one-inch lift or the more extreme Rancho package should be an H3 that takes its off-pavement capabilities to the extreme.

marin8703
06-27-2007, 05:17 PM
nice tips :beerchug:

stagger_lee
06-27-2007, 05:56 PM
I dont know about the front locker, but the pics look nice. I hate flares, but rims are saweet! I want beadies. :beerchug:

usetosellhummer
06-27-2007, 06:13 PM
WTF shackles? naaa I keep it just the way she is thank you. I want those bigg a$$ fender flairs from Japan!

Desert Dan
06-27-2007, 06:33 PM
What did they do with the rear suspension? A Spring over conversion?

I'll take the front locker, any part number out there?

dochummer
06-27-2007, 06:33 PM
that should be how the alpha comes standard...

HummBebe
06-27-2007, 06:42 PM
The first part of the article below...


Engineers make extreme Hummer:

Soup it up
Engineers make extreme Hummer
Larry Edsall / Special to The Detroit News

As part of their support of Rod Hall's off-road racing team, Hummer engineers needed a vehicle for testing components they were developing for Hall's Baja 1000 race vehicle.
So they took a standard Hummer H3 and did some modifications that can serve as a template for anyone interested in taking his or her H3 more toward the extreme of off-roading.



Here is a description of the mods on Rod Halls H3... http://www.entertainmentengineering.com/v3.issue11/EE_v3i11.pdf

Article starts on page 9


As for the springs, the Team HUMMER H3 uses
higher-rate front torsion bars than production and the
rear leaf springs are stock components. The vehicle’s
factory 16-inch wheels provide a stock appearance, but
to accommodate the taller-than-stock 35-inch-tall tires,
the body was raised on the frame by one inch, using
solid body mounts.
The racing H3’s engine is based on the production
3.5-liter inline five-cylinder engine. Per the rules,
Team HUMMER made minor internal changes while
retaining the original cylinder block and head. A raised
compression ratio boosts horsepower to 248 and torque
to 238 lbs.-ft. The compression change enables the
engine to perform well on 100-octane racing gas. Also,
the engine-driven cooling fan was replaced with electric
fans freeing up some horsepower. The engine draws
air through a stock air cleaner mounted in the cab and
sends exhaust out a custom, low restriction exhaust
system.
The H3’s factory-installed Hydra-Matic 4L65 fourspeed
automatic transmission is used, with only slight
calibration adjustments. It sends torque to the stock
transfer case and axles, which use the factory 4.56:1
gear ratios. The stock oil and transmission coolers are
used, but an auxiliary trans cooler also is employed.
The most dramatically altered area of the racing H3 is
the purpose-built interior. It has been stripped of all its
upholstery, trim and convenience features and replaced
with only safety items and racing control items. The
trim panels, carpeting and other accoutrements are
removed in order to help offset the weight of a custom,
protective roll cage, which crisscrosses the interior.
Also included in the interior is a fire suppression system
routed to the engine, several fire extinguishers and a 44-
gallon fuel cell.
A pair of front racing seats replaces all of the H3’s
stock seats; one for the driver and the other for the codriver.
Racing five-point safety harnesses also replace
the factory safety belts (the air bags are deactivated
for racing). Air conditioning is eliminated, as it saved
valuable weight.
The H3’s instrument panel is stock and all the original
gauges are functional, but they are complemented by
a custom control panel and a PI Research data logging
system, which provides feedback on key powertrain
operations. A tracking system also provides real-time
positioning information that allows race officials and
anyone with an Internet connection the ability to track
the vehicle during a race. This is helpful in ensuring
the vehicle accurately followed the course and provides
location information in case of a crash.
“Performance in off-road racing isn’t just about speed,
it’s about strength” said Stump. To track the Team
HUMMER in the 39th SCORE Tecate Baja 1000 on
your computer, follow the link below on November 16
and 17.

Steve - SanJose
06-27-2007, 06:45 PM
Nice mods that work. Even the fender flares are subtle. Too many lifted rigs are really setup to just look cool at the supermarket.

usetosellhummer
06-27-2007, 07:41 PM
amen brother

h2co-pilot
06-27-2007, 08:12 PM
X3 Steve :iagree:

Yea, I thought it was cool too. Nice for someone to come along, do the research and tell you exactly what you need.
Especially coming from those guys.:beerchug:

HummBebe
06-27-2007, 09:58 PM
but but but it has nothing to do with Rod Hall, and a Rancho Lift??? Seriously?

Who "extreme off roads" with a lifted truck?

Hal
06-27-2007, 10:18 PM
Just remember, their mods are geared for high speed baja off roading. I think the majority of us want to gear our off road mods toward low speed trail riding, rock crawling and extended back country trips. Low center of gravity is a must so that they don't flip at 100 mph off road, but I would rather have more ground clearance, flex and suspensoin travel at low speed.

So what did they do to that rear end? it sure looks like a spring over axle conversion. I think I want whatever they did back there.

h2co-pilot
06-27-2007, 10:31 PM
I don't know what you guy's are reading, I saw the 1 inch lift done with spacers and longer bolts, 35s and adjusting the brushguard and fan shroud to prevent rubbing.

I didn't think it was that EXTREME... ((echo)).:giggling:

The actual one they race is totally and expensively modded almost to the point of non-recognition. This was what the engineers that support the research came up with for H3 owners in general. That's all.

HummBebe
06-27-2007, 10:59 PM
I don't know what you guy's are reading, I saw the 1 inch lift done with spacers and longer bolts, 35s and adjusting the brushguard and fan shroud to prevent rubbing.

I didn't think it was that EXTREME... ((echo)).:giggling:

The actual one they race is totally and expensively modded almost to the point of non-recognition. This was what the engineers that support the research came up with for H3 owners in general. That's all.

Cosmetically maybe, with light bars and such, but it's a stock class, the aren't allowed to "mod it beyond recognition".

The engineers in the article posted are modding the H3 with a front suspension lift.....Rod Halls H3 does not have a suspension lift, it has a body lift, per the link I posted. Completely different.

The title of this thread is "Hall's tips for 4x4 H3 mods", the link below it says "Engineers Make Extreme Hummer".

Really, I just don't think people should believe the a Rancho lift will make their HUMMER H3 an extreme wheeling machine. Or, that Rod Hall would recommend it...the lift I mean.That's all.:)

h2co-pilot
06-27-2007, 11:19 PM
Cosmetically maybe, with light bars and such, but it's a stock class, the aren't allowed to "mod it beyond recognition".

The engineers in the article posted are modding the H3 with a front suspension lift.....Rod Halls H3 does not have a suspension lift, it has a body lift, per the link I posted. Completely different.

The title of this thread is "Hall's tips for 4x4 H3 mods", the link below it says "Engineers Make Extreme Hummer".

Really, I just don't think people should believe the a Rancho lift will make their HUMMER H3 an extreme wheeling machine. Or, that Rod Hall would recommend it...the lift I mean.That's all.:)

Again, it said all you need is 1 inch spacers versus a 4" Rancho lift. Read it how you want to. It's just an article. I would try it if I had 35s.

I promise I won't make you or anyone do it.

I edited the title- happy dumb****.:rolleyes: I think Rod can sleep now.

Desert Dan
06-27-2007, 11:38 PM
I don't think Hall uses Rancho stuff for racing

Steve - SanJose
06-28-2007, 12:52 AM
Just remember, their mods are geared for high speed baja off roading. I think the majority of us want to gear our off road mods toward low speed trail riding, rock crawling and extended back country trips. Low center of gravity is a must so that they don't flip at 100 mph off road, but I would rather have more ground clearance, flex and suspensoin travel at low speed.



Yes. And low center of gravity is very important for most of us that drive ourselves and our families 90% plus on the street at speeds up to 80mph daily (in California and Nevada).

HummBebe
06-28-2007, 02:43 AM
on the engineering truck, which features a four-inch Rancho front suspension lift (see www.gorancho.com (http://www.gorancho.com/)).


The truck they are referring to has a 4 inch lift, not something the Hall truck has.:D

SR1355
06-28-2007, 03:04 AM
Seen that truck in person this past April at Silver Lake Dunes... the spring over conversion was trick if your looking for a lift and more clearance under the axle...

h2co-pilot
06-28-2007, 03:16 AM
I am going to explain it for the paste lickers.



This article is about an "Extreme" template that GM engineers that support and work for Team Hummer owned by ROD HALL made. They spend their days screwing around with your vehicle and checking it's performance off-road.

IN the midst of the article about the "extreme" H3 they built- with a 4 inch RANCHO lift and did some other pretty cool stuff too, imo. They mentioned this as a tip:

Hubbard added that 35-inch tires also are something that serious off-roading H3 owners will want to consider. However, he suggested those owners not go to the extremes the engineering team did. Instead, he said all they really need to do is to do a one-inch body lift, which can be done with a dozen one-inch spacers and longer bolts.

He noted that the H3 brush guard can be adjusted to hide any resulting gap at the front of the vehicle and that the H3 fan shroud can be rotated to prevent the possibility of rubbing.

Hubbard said this setup is practical and maintains a lower center of gravity than the more extreme measures on the engineering truck***, which features a four-inch Rancho front suspension lift (see www.gorancho.com (http://www.gorancho.com/)).


*** in which the original article is about.

I suggest if anyone thinks that what they have done to the template in the article is not "extreme" or offends them in any way, they may call or write them on the website.

I was posting the article for the tidbits of tips and the rest of it's content for its relative coolness.

HummBebe
06-28-2007, 03:28 AM
Crystal clear now....thanks:D

Has anyone on the board done a bodylift to accomdate their 35's ?

I'd like to hear about it. I think I mentioned it a while ago, but it was brought to my attention that I would not be able to now, unless I wantyed to change everything back bumpers etc....

I think it would be cool. Not sure that it's necessary tho.

Sewie
06-28-2007, 03:54 AM
I just don't see the point of a body lift on an H3. The main purpose is to allow clearance for the tires. We can already fit 35's fine the way it is.

deserth3
06-28-2007, 03:59 AM
About the only thing in their list I'd be interested in is a front locker. And maybe a set of 35's for Moab use.

Mr_Pat
06-28-2007, 04:51 AM
front locker

X2

H3slate
06-28-2007, 04:47 PM
I love the look of the rod hall Hummer.

http://i91.photobucket.com/albums/k301/knappe18/tn_geyserbros_laughlinparker070.jpg


They did some custom suspension work up front. The body lift would only help if you had more suspension travel than stock right? It wouldn't give you more ground clearance, and if you are already getting full suspension travel with only a little bit of rubbing I don't see how it would help.

When I get 35's I would definitely want the higher spring rate torsion bars, the fox shocks, and the newer, stronger tie rods.

Wisha Haddan H3
06-29-2007, 01:07 AM
... When I get 35's I would definitely want the higher spring rate torsion bars, the fox shocks, and the newer, stronger tie rods.
x2

Idaho-Hummer
06-29-2007, 02:54 PM
When I get 35's I would definitely want the higher spring rate torsion bars, the fox shocks, and the newer, stronger tie rods.

x3

Desert Dan
06-29-2007, 04:09 PM
x4

I like the side mirrors too. Less likely to get snapped off by branches:)

GotSandH3
07-06-2007, 05:29 AM
A lot of Chevy Colorado drivers have done the rear spring over axle conversion... Looks very simple to do...My H3 is my daily driver so its kinda hard to tackle a mod like that...