Congrats! I can't wait to see this thing on the road.

i was actually wondering if there would be benifits to the 3.73 in the rear and a 3.48 to keep the transmissions from shifting at the same time right now they shift one right after the other....it F*&king seamless! lol and the front (while really heavy the car is 51/49 weight dist f/r) trans wont have the weight transfer on launch so a taller gear would help on top end (Al dreams of taking the 442 to the salt flats )

one thing i considered is to have us get two 3.73 geared units and have a sepereate strip/street setup for the front trans shift points...if we have traction problems up front

you realise how heavy the 442 will be with two 4T80E'* two Turbocharged 3800'*

i'm thinking the next time we run Al'* skinny *** across the scales the car weighs 4600 lbs (and we ran 1.90 60'* at 4330) but with alot more power

4wd rules

oh i just said that so if anyone is considering this in their ride they can get an idea of what needs to be modified for PS headers (i only took a couple of measurements) if you want pics posted i can (for future swappers)

talked to a buddy and he suggested them they can do anything he said there was a good chance they can machine a setup similar to the aftermarket double and triple disk (TD truck) TCC assembly and fit it in the 4t80e converter...

he suggested i bring em a core converter and a couple of guys will cut it open and tinker with it (who knows if the LS4 equipped W bodies have the 80E with the viscous clutch?) they are always looking for new products to sell besides depending on what they can do we'll be buying two

i'm also thinking it would be nice to switch the converter to a 6 lug arangment

what are your thoughts oin the differences in the 4L80E and the 4T80E (internals wise) i have rebuilt a L not long ago

give em a call they are right next to rt20 in rockford (they did a couple of converters for me when i worked at Wayne'* World a TH400 and 4l80e)

Midwest Racing Converters
"Good Enough...isnt Good Enough"
3535 Kishwaukee St
Rockford IL 61109
(815) 229-9808
fax (815) 229-9874

depending whether we sacrafice the built 4T60E from the front of the 442 into this salvage title 98 Lumi is how soon the 80e is purchaced for test fitting in a first gen W
i already can get a 75$ core unit for spare hard parts and i'll be grabbing the next 80E converter i can grab easily to have them tinker with

Alot of quotes, hope I don't get too confusing:

I bought a converter from Transmission Crafters in Albany, GA. They built a Allante converter (B23) that uses a conventional clutch, not the viscous. All the 4T80 converters are furnace braized, so they can't tweak the fins at all (more stall). I called Midwest, they wanted 195.00. I paid 110.00 for the Allante converter.

You saw the pics, I built the rear header to clear the shifter and switch.

Sounds intriguing. I'm sure it would work since the two drivelines are not connected. Obviously you couldn't do it on a real 4wd. What you really need is a stand alone transmission control module to run both transmissions simultaneously. That way they are both commanded to shift at the exact same time!

The -80 weighs about 50lbs more than the -60/-65.

You got that right! I can;t wait for the day when I start building my AWD 6000. I am planning a 3900SFI/turbo for it. Hopefully about 400whp(?!?!?)

It was hard enough to get the 4-bolt drilled into the 3800 flywheel. I had to notch the counterweight in two places and add back the weight with the mig welder (see the pics)

two totally different transmissions, no interchangeable parts. Not like the old TH400/TH425

My next is to buy a junk 97-up W-body k-member and try the 3800/4T80 in it. I'd like to sell a package to the hi-hp GTP guys, with LSD. BTW, The LS4 W-bodies use a new 4T65E-HD with 5-pinion planetaries and beefed-up internals, GM billet input shaft, output shaft, etc.

Wouldn't it be better for them to shift at seperate times, that way there is always a drivetrain putting power down?

Maybe? I don't know. Hot Rod magazine, way back in 1987 or '88, had an article on a twin engine Honda CRX. They were identical CRX engines/transaxles. I'm not sure, but I think they were automatics. I remember distinctly, and the writers were quite surprised, that one engine was slightly overdriven by the other. It could be the very same principle I expect to put in use with the twin-charging, and that is this: when two engines are used, neither has to work as hard, and one pushes the other.

Which brings us back to my project....

(I am killing time waiting for an ebay auction the end... I have 44 minutes, so sit back, sip some hot chocolate and enjoy)

When the */c is sucking in atmosperic pressure, it has to overcome any/all restrictions in the intake tract - the MAF, the throttle blade, the upturn in the blower entrance, the flattening-widening of the roof of the blower - then, the air at atmospheric pressure gets pulled into the rotors and sqeezed out below. All of this work is done by the crankshaft via the belt and pulleys.

With a turbo providing pressurized air into the blower, the blower doesn;t have to work as hard to pull the air in. AND actual pumping losses inherent in a */c are reduced to nearly nothing due to the turbo "pushing" the rotors.

Here'* an example everyone can understand:

As a kid, I remember playing with a pinwheel, you know, the colorful plastic wheel on the end of a plastic stick. In the house, or on a still day, the only way to get that thing to spin (*/c) was to flick the end of the blades with your finger. The thing would spin about three turns and stop (let'* face it, the tolerances on that thing were like .062" on both sides... they had a butt-load of runout!). If you could flick thatthing over and over you could get it going pretty fast, but as soon as you stopped flicking it, it would go another three turns and stop. This is the */c. As soon as the crank stops turning, the */c stops, too.

NOW, something really cool would happen if you started running thru the house holding that pinwheel out in front of you - the dad-blamed thing would start spinning on it'* own!

WOW, COOL!!!!

When you introduced moving air in front of the wheel, it would spin all on it'* own! And the faster you went, the faster it would spin. You could never get it spinning that fast just by flicking it with your finger (nor would it accelerate as fast).

I anticipate, and expect to demonstrate, that a turbo feeding a */c as little as 1psi above atmospheric pressure will show significantly more power gain than 1psi boost would normally provide, based almost entirely on the reduction of pumping losses in the */c.

What does this mean in the engine? A roots-type */c is one of the LEAST effective power adders, taking away a huge percent of power.



At average boost levels, the M90 can use as much as 50hp. Some very knowledgeable folks in the 3800 market claim that at extremely high boost (25-up), the M90 can siphon off as much as 150hp just to turn it!

Ever hear about the draft? Not WWII, Korea, or Vietnam, but NASCAR! The car in the front uses less power to stay there b/c the car behind him is pushing him! (the car behind also has the added benefit of reduction in wind drag across the front of his car!)

So, what does thismean in the engine? Since the */c is not working as hard, it does not produce as much heat. That'* good. And since it is squeezing air that is already squeezed, it doesn't just add boost, it multiplies boost.

Ex: 10psi turbo pressure and 10psi */c prssure DOES NOT EQUAL 20psi. It goes like this:

10psi turbo = 1.67 pressure ratio (p/r) is 14.7psi atmosperic pressure + 10psi boost pressure = 24.7psi total pressure. Divide that by 14.7psi atmoshperic pressure to getthe p/r = 1.666666 or 1.67. Now, take that and increase it by ianother 1.67 p/r and you get this:

1.67 * 1.67 = 2.79 * 14.7 (atmospheric pressure) = 41psi total pressure - 14.7psi atmospheric = 26.3psi boost pressure.

10 + 10 doesn't equal 20, it equals 26.3! LOL!!!!!!!!!!!!

(31 minutes and 12 secs left)

The reason not too many people try this is b/c it is way too easy to make insane amounts of boost! If the turbo is not carefully controlled, it can get crazy.

At shown on the chart above and quoted from some bright guys, at 26psi on all */c, you'd be losing 150+hp in pumping losses! And producing insane amounts of heat! If you had a turbo doing all that work by itself, the same thing would happen - you wouldn't have the extreme power loss, but you would have an insane amount of heat requiring a huge air-air intercooler and it'* long charge air piping, or expensive an liquid-air intercooler with it'* plumbing, coolant pump, heat exchanger, and all the necessary hardware. Not to mention a turbo getting to 26psi would take a day and a half! That'* some serious lag.

I can;t wait to start experimenting with this. There is alot more than I have typed about here. Like turbo size and */c speed. Oh, well, time to go bid on the turbo in question!

Hope you enjoyed this (or at least, I didn;t bore you to tears, but then if it was that bad, you probably didn;t read it all anyway and certainly didn;t get to this sentence, so no apologies necessary. All right then....)

Slight hijack. Steve Mosler'* original TwinStar Eldorado used two different years of N* motor, with different gearing in each 4T80. He said the shifts took just slightly longer than normal, because the computers couldn't figure out the shift while it was still accelerating. But the difference in shiftpoints helped the car'* performance. He also said that the sound of the dueling engine notes was really freaky.
The Twinstars he built for sale all used matched drivetrains, though, but you still get mis-matched shifts because they couldn't be commanded together.

That is interesting.

BTW, I won the turbo.

Chinese knock-off, but for $137.50, if it'* a POS, I'll just use it as a door stop.

http://cgi.ebay.com/ebaymotors/ws/eB...m=250079004779

Interesting turbo. You got full specs on it?