Is there such a thing as too much power?

Guys,

I have been looking into doing my engine and trans swap this winter and when I sent out my new 4BT Cummins to get painted etc. the guy at the shop was talking to me about performance packages they can do and have done. My question is, is there such a thing as too much power in the H3? What is the point in which the weak front end combined with 35" tires just gives way to high end torque? Is 550 ft pounds of torque too much? I know a few of you have done 6.2 liter swaps and from what I can tell 1 went to a 2 wheel drive to 4 wheel drive select setup to only put high power to the rear. It is not unrealistic to have a 4BT pushing 350hp and 700torque with twin turbos.

My dad used to race at Lyon's drag strip in the late 50s/early 60s. One of his friends (until about 5 years ago) had his car that was a twin to my dads.... The rear axles they were using, with slicks, were smaller than the front axle of a H3. They ran 8s 1/4s. To say they were weak would be an understatement but they also had 300lb to press clutches and manual transmissions - yet few broke axles... it was all in technique that kept them from scattering into pretty bits. There are some people who are so hard on stuff that they could break rocks with feathers. Others, like my dad, did just fine with weak parts. It truly is all in how you drive. If you want to rock bounce, get a dana 60 under the front and 14 bolt in the rear.... or don't be a meatsack and drive with finesse.

is there such a thing as too much power

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Where to start. There is no such thing as too much power. Until you wreck because of it, or you break parts.

What is the point in which the weak front end combined with 35" tires just gives way to high end torque?

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The stock I5 in the right conditions and terrain.

It is not unrealistic to have a 4BT pushing 350hp and 700torque with twin turbos.

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That is 10# of poop in a 5# sack in the H3 engine bay. You will need several inches of body lift to fit a high mount high pressure turbo to find room for the large low pressure in a low mount. Will require a remote oil filter for sure. Do you still want your A/C? You will have to find somewhere to put the compressor where it won't be in the way of the turbos and intake. You could possibly use up some of the room over the fender where the airbox and puke tank are if you gut all that out, but then thats a lot of unsupported weight hanging way out there. Those power goals will definitely require intercooling and packaging that in. Those power levels will likely require upwards of 60# of boost pressure which will require head studs and possibly ringing the head.

[FONT=arial, sans-serif]200hp with a set of headstuds, injectors and minor adjustments. The hx35 turbo will support up to 425hp in a single turbo application saving room over the twin setup. Yes I do want the A/C. I was thinking of doing an inter-cooler setup like they do with the H1's on the front hood? Not sure if that is possible or not.[/FONT]

Maybe something like this on the hood for intercooling?

My point on suspension:

Im running 35s and a cammed 6.2 pushing 520 tqs at peak. With a stall my truck launches at 3500 rpm and thats around 400 tqs on the engine dyno and at this point all tires are spinning and the truck suspension doesn't handle it too well (I have stock 4.10 gearing too)
Basically the truck suspension loads and unloads unpredictably and the nose lifts up severely. Several times the truck would stir completely from its lane and pull to another lane just due to tremendous torque steer which is dangerous btw (and that was from a 20 mph rolling start!!!)

Point is, for a D.D. on the street the H3 will need stiffer suspension to handle 450 + torques if you are planning to floor it once or twice.
700 tqs, thats tremendous...

I think you know my answer....

Love it!

4speedfunk said:

I think you know my answer....

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Is that a 69 Impala?

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What would be a good starting gear ratio for 37" tires and 631 tqs with a 6 speed manual trans? 4:10 Casey?

Casey has mentioned before that the trq he was putting out with his 4BT seemed to be enough to overpower the traction control on his H3. I don't know if he got that part sorted though. I don't think there is any way the TCS and Stabilitrac would be able to work with 700 lb/ft of torque. I also think that a 700 lb/ft 4BT would have enough off idle to strip a front ring and pinion if it was even bound up a little. You may need a to pull the H3 body off the frame and bolt it on top of a whole other frame.

GreatDaneHummer said:

What would be a good starting gear ratio for 37" tires and 631 tqs with a 6 speed manual trans? 4:10 Casey?

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I would think that 3.73 gears would be cake and that 3.42 might start to make it sweat a little. It would of course depend on what the ratios in that 6 speed are.

It should be pretty close to this:
3:10
1.81
1.41
1.00
0.71
0.61

R: 4.49

Casay is making 135hp or so and 350 tqs is this correct? Not sure if I remember someone saying around that.

Mine dyno'd in today at 315 and 631.

Is that a 69 Impala?

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Yessir.

Motor:
502 crate motor (450 hp & 550 ft.lbs at 3200 rpm). Barry Grant 750vs, AeroMotive fuel system, Headers, 3" SS exhaust with Edelbrock SS turbo mufflers & turndowns, OEM 4-row desert cooler radiator, solid motor mounts. Motor is 100% stock rectangular port heads & dual plane GM intake, hydraulic roller cam. Was originally a 350-AT car. Did have AC...now has American Graffiti heater delete kit.
Trans:
Tremec TKO-600 5-speed manual (w/ .80 overdrive). Hurst shifter, Billet Flywheel, Centerforce clutch, Lakewood bell housing, Roller pilot bearing.
Suspension:
Stock front suspension with 90/10 Lakewood drag shocks.
Original 12-bolt with Eaton Kevlar posi, Richmond 4.11s, stock axle shafts. Stock rear 4-link with custom adjustable upper mounts and adjustable links. Custom lower links. All urethane bushed. OEM rear sway bar (F41 option). Airbags. Gabriel shocks. Custom driveshaft & loop.
Other:
Bone stock triple black (ext.-int.-vinyl roof)...one repaint in the 70s. No rust EVER. No wrecks. Been rained on once in 15 years. Interior has new carpet, original buckets, console, tilt wheel, OEM radio delete plate. Floor hump was enlarged for Tremec trans. Stock original 4-speed console. Has Alpine speakers mounted and wires ran back to the glove box (for I-pod or whatever)...no head unit. AC, cruise-control removed but still have. PS, PB, tilt-wheel, buckets, F41 police package suspension, wipers are functional but removed.

Runs 12.90s at 107mph with 9" DOT drag radials, mufflers. Left front hops a beer can when it hooks. Weighs in at a hefty 4400 lbs. Very driveable...8.5:1 compression ratio. Cruises at 60mph at 2000rpm in 5th gear.

Soon to be for sale. I must sell this boat to afford a sail-boat.

rsc said:

I would think that 3.73 gears would be cake and that 3.42 might start to make it sweat a little. It would of course depend on what the ratios in that 6 speed are.

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I think I remember reading he wanted to gear down to 3.73 with his engine and open up the boost.

As for traction control being overpowered, @ 400 tqs the TC is non-existent!

Once a long time ago needed a new engine for my 73' CJ5 to replace the 258ci straight six. Acquired a 232ci engine from a man who swapped out his 232 in a CJ5 for a 390 V8. Took his Jeep out for a run. Yes you can get to much power? Just my HO.

You will probably need to be 4.10s with tha much overdrive and 37s.

Go to grimmjeeper.com and enter your combos. Shoot for 1800 rpm at cruise for best fuel economy.

I cruise at 2000 at 70 with 35s, 4.10s and 0.696 overdrive. I stayed on the high end of the economy rpm to keep from hammering the transmission. I feel I could easily go to 37s on this gearing.

Got a dyno chart of that run? How hot are they pushing egts and how much boost to get those numbers on an hx35? Is that intercooled or non?

I've seen this car in person. Perfection,everything I would want in a cruiser. (4speeds Chevy)

amrg said:

Several times the truck would stir completely from its lane and pull to another lane just due to tremendous torque steer

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Was there for this test.. Its a frighting amount of power in a truck, I never thought I'd see the H3 move this quick.

That said.. It was an AWESOME experience.

About ten years ago, a young neighbor bought a Viper as his daily driver. He commuted on the busiest freeway in LA everyday. In a few months, he traded the Viper for a 528.

let me know when you put it for sale!