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Center mount turbo

buddy said:
The 4l80E can handle a lot, but most of them have 200,000+ miles on them, and who know what former abuse. Hot rods put them in, but they dont tow stuff to get them really hot. And GM wasnt very nice about giving you good pressures for handling more power. A tuned tranny would be happier than a modded one. And then there are the later model versions that should hold up better.
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A good cooler ELIMINATES heat buildup. So that isn't an issue.
a tuned trans does NOT have the capability of a modded one. That's why we mod them.
 
Yes, a good cooler could eliminate that, but Im just saying we dont have them stock, and so when you get it, the trans could have been through a lot of stress.

A tuned trans can do better. And by modding I mean the shift kits to get higher pressures. If you want 100psi line pressure I can just program it in, but still only 20psi at idle. If you want more at shifts the program can do a shift only modifier, rather than needing the line pressure always high. I do recommend other reliability mods, but not shift kits that mechanically raise the pressure over programmed. I can customize the pressure for throttle percentage and vehicle speed to lower it at cruising situations, but raise it up when youre using lots of pedal.
 
It will take more than 100psi to cope with what we have under the hood. Tuning alone can't get enough pressure to make the shifts happen fast enough.

You are correct, my trans has 266,xxx miles on it. I hoped it would go a few more miles with the transgo. Obviously not.
 
And GM only gave it 56psi line pressure at near full throttle. So imagine running a stock TCM and trans with turned up DB2 and boost, or fooling a stock PCM to allow more boost or a little more fuel but still same low tranny pressure. Or an aftermarket PCM that gives you a lot more fuel and allows more boost, but did not address the tranny. These are some of the issues the tranny has to deal with, starting with GM's conservative programming in just enough pressure and very litte temperature compensation to boot, until it was already too hot. The programming can get you over 100psi with modifiers, like tranny temp and shift modifiers. So I would say anyone with a stock PCM or normal performance mods doesnt really need a shift kit, they just need a reflash that addresses the tranny. And maybe just a sure cure kit for the common wear items.

There are special cases, like this one, where additional measures may be warranted.
 
So you can tune my trans? I am using the stock tcm. The shift points are beautiful. But this kind of failure rate is simply more than I can afford :)

The 99 trans I have here is also toasted. So... it's rebuild time... and then it will HAFTA work :)
 
buddy said:
And GM only gave it 56psi line pressure at near full throttle. So imagine running a stock TCM and trans with turned up DB2 and boost, or fooling a stock PCM to allow more boost or a little more fuel but still same low tranny pressure. Or an aftermarket PCM that gives you a lot more fuel and allows more boost, but did not address the tranny. These are some of the issues the tranny has to deal with, starting with GM's conservative programming in just enough pressure and very litte temperature compensation to boot, until it was already too hot. The programming can get you over 100psi with modifiers, like tranny temp and shift modifiers. So I would say anyone with a stock PCM or normal performance mods doesnt really need a shift kit, they just need a reflash that addresses the tranny. And maybe just a sure cure kit for the common wear items.

There are special cases, like this one, where additional measures may be warranted.
Click to expand...

I don't have my book in front of me because I'm on the road, but I believe base line pressure with the force motor getting max current only drops down to about 55-60 which is as low as it can go. No current or full pressure should be up around 150 or so bone stock in drive, and around 225 in reverse. I'm not 100% on the pressures, but I know it is alot more than 56 at WOT as that would be idle or base pressure.
 
TCI I think it is has a 6 speed based on the 4L80E now. Its rated for 3 times the HP a 6.5 would ever put through it. I have not seen a price but I bet its big $$$. Sweet though.
 
L98TPI said:
TCI I think it is has a 6 speed based on the 4L80E now. Its rated for 3 times the HP a 6.5 would ever put through it. I have not seen a price but I bet its big $$$. Sweet though.
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Is that a dare? LOL !!

Must check this out. It sounds like something I'd like...
 
Yea I have a truck to be working on but being jobless at present doesn't get things moving at all. And I have so much more left to do coatings(damn sctrailrider), delta cam, valve job and blending of heads, van exhaust manifolds, list goes on and on and on. Old saying holds true..."Too much month left at the end of the money"

Points for anyone who can tell me who sings that :p
 
To anyone considering transgo for their 4l80e- BEWARE... much carnage happens.

The better safer option: Jakes performance in texas. Friendly customer service. I needed a full rebuild kit for the 99 trans I have here. They told me they didn't have one in stock, but he gave me the part number of the kit they use, and I got it locally. Also gave helpful hints on how it goes together, and some of the mods they do for reliability.
If you call them, dial extension 103 for Mike. Leave a message... he WILL call you back!

Now... I must get back to work and install this trans!
 
So... got my old trans apart. Broken case lugs on second gear, and blown gaskets on the valvebody.

It would appear the transgo pressure regulator was incorrectly machined, and was binding under pressure, causing max pressure at all times. So, I can't say a transgo kit is "all bad". But it does need "professional installation" as you MUST make SURE the pressure relief valve is working.
 
Cumminsfever said:
So... got my old trans apart. Broken case lugs on second gear, and blown gaskets on the valvebody.

It would appear the transgo pressure regulator was incorrectly machined, and was binding under pressure, causing max pressure at all times. So, I can't say a transgo kit is "all bad". But it does need "professional installation" as you MUST make SURE the pressure relief valve is working.
Click to expand...

All shift kits require proffessional installation as issues like this are more common than most will admit.
 
nmb2 said:
why not just buy an ATS tranny and 5star converter and be done with it?
Click to expand...

I could never disgrace ANY of my vehicles with an ats product.

Talking with alot of top dragracers. The ones that use 4l80 based trans refer to Jakes as the place to go.
 
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