IDI vs Pws

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Oct 23, 2007 | 04:48 AM

#106

Agemenon

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From: Edmonton, Alberta Canada

I'm always up late, anyways....I like my C6, the E40D doesnt sound all too powerful to me. Not to mention I'd have to go find a 4 speed steering column....another 300 bucks. Besides, I figure its quite possible to get somewhere around 1500rpm with 3.08's and a GV unit.

Oct 23, 2007 | 11:19 AM

#107

Finnzo

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Joined: Sep 2007

Posts: 69

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From: Corvallis/Albany, Ore.

Quote:

Originally Posted by Agemenon

So you cant mix a 3.08 rear with a 3.55 for a front for example? What would be the consequences of that?

Well ... off road, you'd have a lot less traction and steering because one wheel would be skidding/spinning at all times and if it was the downhill front one, say, while you were quartering down a 20-percent grade to get around a bunch of trees, that could be bad. On the road, if you forgot to disengage 4x4, your axles would wind up instantly and generate huuuuuge forces in both pumpkins and the peanut, the tires would chirp and something might break ... and you'd probably have some trouble getting the peanut out of 4x4. All in all, plenty more trouble than it's worth, IMHO ...

if you're changing gears anyway, have you considered popping a locker in there? It's not as good as full 4x4 but it's a lot better than an open diff ...

--Finnzo

Oct 23, 2007 | 11:29 AM

#108

Finnzo

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Joined: Sep 2007

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From: Corvallis/Albany, Ore.

Quote:

Originally Posted by Finnzo

Oh, whoa, there's EIGHT PAGES to this thread! I just hopped into the first one adn thought I was at the end. Sorry if I duplicated anything!

--Finn

Oct 23, 2007 | 03:24 PM

#109

David85

Lead Driver

Joined: Nov 2003

Posts: 6,900

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From: Campbell River, B.C.

Quote:

Originally Posted by Agemenon

I figure its quite possible to get somewhere around 1500rpm with 3.08's and a GV unit.

Actually its not. The torque converter will only start to transfer torque after the engine RPMs reach the stall speed, and stock stall speed is usually close to 2000 RPM. Even with a so called tow stall converter, I still have a lot of slushy zone below 2000 RPM.

Thats what I meant when I said you will not get a proportional reduction in RPM if you combine 3.08s and a GV overdrive at 100 KPH. 1800 RPM is my best guess as to how low you can go with an open TC, but if accellerating or climbing a hill, the revs will drift up, which is not alltogether a bad thing.

To give you a picture about what I'm talking about, I can actually start off on 4th gear with my transmission, but the lowest the revs it gets, is 1800, as I accellerate. It will hold between 1800-2000 all the way up to 120 KPH, and then will slowly climb.

Oct 23, 2007 | 08:58 PM

#110

starmilt

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Joined: Oct 2007

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From: Faibanks Ak.

I like my 4spd

Oct 24, 2007 | 01:33 PM

#111

Agemenon

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From: Edmonton, Alberta Canada

ok...so whats the difference between an open TC and a locking TC?

Oct 24, 2007 | 02:50 PM

#112

David85

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Joined: Nov 2003

Posts: 6,900

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From: Campbell River, B.C.

Quote:

Originally Posted by Agemenon

ok...so whats the difference between an open TC and a locking TC?

Exactly that....locking.

An overly simplistic way to think of a torque converter, is to place two fans facing each other, if you power up one of them, the other will start to spin.

Locking torque converters have the same basic principle as the open, but they also have a clutch that activates to remove ALL SLIP, so now your calculated drive ratio is the actual drive ratio, as long as the TC is locked. In most cases, the TC will only lock in top gear, and is disabled below a preset speed to prevent stalling the engine.

The E4OD has a lockup TC, the C6 doen't not even aftermarket. But I wouldn't think too much about a tranny swap just yet, since it will already be a night and day difference with 3.08s. 2000-2300 RPM can still be economical, and realistically, even a strong head wind can force me to downshift out of 4th gear @ 100KPH, usually I only use overdrive above 110 (which is testing the legal limits anyway).