I have found thread after thread documenting installs with the 4t60, 4t65, f23, f40, etc... but I have seen little info on the 4t80 install with a 3800.

Just had a few questions if anyone knew the answers.

1) Mounting, the same or different? Furthermore does the combination fit in a fiero. I've seen it with a northstar, but wasn't sure if it would work with the 3800.
2) Axles, Obviously this is doable because it's been done with a northstar conversion.
3) What else is required for the install other than the following: Lower knock sensor relocation, redrilling of the flywheel if it's a 4 bolt torque converter as in the aurora mated 4t80's, and slight modification of one part of the block where it mounts to the transmission, and cut a place out for the starter.

I'm having a hell of a time finding a remotely good deal on a 4t65ehd here locally and the 4t80 is a dime a dozen. Also I'm going to be pushing a fairly high amount of horsepower with a twin turbo series III and I don't want to dump thousands into modding a 4t65ehd.

[This message has been edited by jasonfox (edited 04-16-2011).]

The has been talk of the 4t80e working behind the 3800. I have read a few threads where it's been attempted, but I have never actually seen one 100% finished.

I myself have talked with Darth Fiero about it a few times. While it's believed that it can be done, it requires a bit of work, including trimming some bits on the block and reworking the shift bracket and wiring harness to the trans. I have no idea about what kind of axle options would be needed.

On ClubGP, I believe forum-member 'Skalor" is in the process of swapping. but if you go this route, I'm 100% certain that you would be the 1st to do this in a Fiero.

quote Originally posted by AkursedX: The has been talk of the 4t80e working behind the 3800. I have read a few threads where it's been attempted, but I have never actually seen one 100% finished. I myself have talked with Darth Fiero about it a few times. While it's believed that it can be done, it requires a bit of work, including trimming some bits on the block and reworking the shift bracket and wiring harness to the trans. I have no idea about what kind of axle options would be needed. On ClubGP, I believe forum-member 'Skalor" is in the process of swapping. but if you go this route, I'm 100% certain that you would be the 1st to do this in a Fiero.

Well, ironically the piece on the block that needs trimmed down broke off on the engine I'm having shipped to myself and it needs welded back. Figure I can make it work at the same time. Also since I'm going to have to wide track the rear suspension I'm very tempted to go this route anyway and see if I can stuff it all in there lol. Anyone know the dimensions of the two transmissions?

Luckily there are threads on here about making axles since the northstar uses this trans. Shouldn't be all that difficult to do that part.

This is just my opinion, nothing more, but why use the 4T80? Yes it's "rated" for a higher torque level, but a 4T65E-HD can easily take anything a 3800 can throw at it when built. My main issue with the 4T80 is the size of it and the unbelievable weight. It weighs around 400lbs wet I think, compared to the 4T65E-HD being around 200lbs wet.

double post

[This message has been edited by jasonfox (edited 04-17-2011).]

quote Originally posted by jasonfox: Had you read anything I wrote you would notice why. I dont' want to spend a fortune on a "built" 4t65e. I think it's retarded. As for weight; my car already weighs significantly less than a stock fiero so who cares. And as for it easily being able to take anything a 3800 can throw at it I think fierox's recent chain break shows that's not the case. 4t80e wet weight is around 295 btw.

Whatever, your loss. Good luck on the wiring/mounting.

Your lack of maturity is inspirational.

The 4T80 is a huge transmission. It has been used on N* and with a 3.4TDC and at least 1 was bolted up to a SBC. It will not clear the LS(x) family of blocks, but I have never seen any information about trying it with the 3800SC engine. Here are a couple of pics comparing the sizes between the 4T80 and the 4T60e:



Here is a pic with the 3.4TDC on a fiero cradle:

[This message has been edited by fieroguru (edited 04-17-2011).]

Not that filters need to be changed often, but the 80 uses two filters. One in the usual location, and one behind the side cover that can only be accessed by removing the side cover. Not sure of the electrical, if a 3800 pcm can run it or not?

I've been told that you need the cadillac torque converter, as it uses a woven clutch that can not be substituted...unless you change the TCC lock up strategy in the pcm. But I believe this is true with the 65 also.

I had a list of the electronic fixes required to convert from a 65e to a 80e. In short, you have to swap parity on a few of the solenoids, and make sure you have the older style PCM that will do pressure control based on PWM.

The flexplate and converter should be pretty straightforward... The axle building process should be about as hard as making some 65e axles.

When you swap parity, do you go from even to odd or zero to one? How about the stop bits?

quote Originally posted by phonedawgz: How about the stop bits?

Brake parts have nothing to do with the tranny

quote Originally posted by jasonfox: Your lack of maturity is inspirational.

I'm 18, what do you expect?

The 4T80E/Turbo 3400 DOHC setup above was was mine. The transmission was heavy and the transmission seemed to soak up a lot of power. It really looked impressive. Chris at West Coast Fiero can tell you about installation which was physically simple . As we had a Twist Machine paddle shifter and an after market controller, I dunno about a 3800 electronics. There is no woven clutch. It had a torque converter.

I have a 2006 4T65HD with about 37K miles for sale for $400 plus shipping from West Coast Fiero located in Tehachapi, CA:



As I think about it, we had to have the aftermarket controller (about$1,000) and the paddle shifter was then doable, so we did it.

Regards

David

[This message has been edited by MountainHiBlue87GT (edited 04-17-2011).]

quote Originally posted by MountainHiBlue87GT: There is no woven clutch. It had a torque converter.

I was referring to the clutch inside the torque converter, the lock-up clutch.

Could be, but mine was from an Olds Aurora. To my recollection, it shifted very smoothly; Granny would have loved it. Broke the right axle at about 40 MPH in low boost.

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Metallic Blue/Silver 1987 Fiero GT - 2006 3800 Series III Drive by Wire; Ported & Polished by TrippleEdge; 1.7 Yella Terra Full Roller Rockers; VS Cam; Tuning by Darth; WCF CAI & 1 5/8 Stainless Headers, 3" Exhaust, Power Steering & Much More; MSD Coils & Wires; Porsche (Brembo) Calipers on 13" Viper Rotors; 18X8 TSW Indy Wheels; Paint by Phoenix Auto in California City.

My biggest concern is definitely the electronics aspect of getting it to work with a 3800. Even if I decide to not do it it would be nice to have a thread finally that covers what's required.

I think you will need a controller.

This is what I used: http://www.powertraincontro...com/transcontrol.php The price is now $750.

Do a google search and a bunch of controllers will pop up.

quote Originally posted by MountainHiBlue87GT: I think you will need a controller. This is what I used: http://www.powertraincontro...com/transcontrol.php The price is now $750. Do a google search and a bunch of controllers will pop up.

you do not need a controller, that is a fact.

[This message has been edited by darkhorizon (edited 04-17-2011).]

Dark:

I gave him an answer that will work.

Why don't you give him a non controller answer that will work?

Regards,

David

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Metallic Blue/Silver 1987 Fiero GT - 2006 3800 Series III Drive by Wire; Ported & Polished by TrippleEdge; 1.7 Yella Terra Full Roller Rockers; VS Cam; Tuning by Darth; WCF CAI & 1 5/8 Stainless Headers, 3" Exhaust, Power Steering & Much More; MSD Coils & Wires; Porsche (Brembo) Calipers on 13" Viper Rotors; 18X8 TSW Indy Wheels; Paint by Phoenix Auto in California City.

Alright, talked to gmtuners and the greatest possible problem to overcome is the pressure control solenoid.

4t80e is set to work at a frequency of 614htz, 4t65e is set to work at 292.5htz.

Any electrical gurus on here want to draw up a quick electrical diagram to solve this problem?

Perhaps a 4T80 E can be tuned to shft quickly, but I found mine to shift slow and soft in full auto or paddle shift.

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Metallic Blue/Silver 1987 Fiero GT - 2006 3800 Series III Drive by Wire; Ported & Polished by TrippleEdge; 1.7 Yella Terra Full Roller Rockers; VS Cam; Tuning by Darth; WCF CAI & 1 5/8 Stainless Headers, 3" Exhaust, Power Steering & Much More; MSD Coils & Wires; Porsche (Brembo) Calipers on 13" Viper Rotors; 18X8 TSW Indy Wheels; Paint by Phoenix Auto in California City.

[This message has been edited by MountainHiBlue87GT (edited 04-17-2011).]

quote Originally posted by MountainHiBlue87GT: Perhaps a 4T80 E can be tuned to shft quickly, but I found mine to shift slow and soft in full auto or paddle shift.

I would prefer that; just need something my hp & torq won't destroy over time.

The 65 will default to full line pressure too if the circuit breaks, as do all GM trannys with electronic pressure control. I can tell you from driving GM autos in limp mode (full line pressure), you will not like it. It shifts hard, but even with very light throttle input.

To me, the 80 would not be my choise. I would use a built 65 first. But I admire your interest and I know it can be done, just wondering at what expense? You can buy some pretty strong parts for the 65. I know you said you don't want to go that route.

Maybe it would be easier to use a northstar pcm and program it to run the 3800?

I do not see a reason why it won't work. Go for it...

FWIW, I have the service manual for my 96 Aurora wt 4T80E. If you need specific data, I might be able to dig it up.

Bob

quote Originally posted by 1fatcat: The 65 will default to full line pressure too if the circuit breaks, as do all GM trannys with electronic pressure control. I can tell you from driving GM autos in limp mode (full line pressure), you will not like it. It shifts hard, but even with very light throttle input. To me, the 80 would not be my choise. I would use a built 65 first. But I admire your interest and I know it can be done, just wondering at what expense? You can buy some pretty strong parts for the 65. I know you said you don't want to go that route. Maybe it would be easier to use a northstar pcm and program it to run the 3800?

Honestly, this picture is what sold me on teh 4t80e



I have seen junkyards sell the 4t80e for as little as $50. Even with buying the $750 controller I'm sitting cheaper than building a 4t65e only to have to build it over and over again as it breaks chains, etc...

I think that this needs to be explored and done by someone; preferably with a simple solution. The 4t65e hd is getting harder and harder to find on car-part.com for a reasonable price.

You can operate the solenoid with the difference in frequency, it works fine, you just have to adjust the pressure to where you like it.

I'm currently running a 65e with a smart relay to run the solenoids. It's just a simple up down counter but it also disengages the tc on any shift. I am running full line pressure and it isn't too bad but obviously not ideal. Shifts are fine, just going from park to gear can be felt pretty good and you better have good brakes. Ryan Hess is also comming out with a controller which should work. There is a thread in General chat. If you want to use my route here is the link. https://www.fiero.nl/forum/Forum2/HTML/105101.html It would probably be best with a 60e though. It cost a little over $120 I think and I use a cadillac shifter with tap shift.

quote Originally posted by darkhorizon: The only part that nobody has ever broken (due to power anyway).

Speaks to the nature of the entire construction of the 4t80e

I've been in discussion with Dave over at www.tripleedgeperformance.com about doing a 4T80-E swap on my 3800 Series 2 Turbo Fiero (which currently has a 4T60-E -- that still works) for some time now. In our discussions, I've learned there has been at least one other guy (with a Grand Prix, I think) who has swapped in a 4T80-E with a 3800 and got it running (presumably with the 3800 PCM). I don't know the fine details as to what he had to do in the tuning or electrically to get it to work, but here's what I've learned from the GM service manual...

The logic for the transmission fluid pressure (TFP) manual valve position switch is identical between the 97-02 4T65-E and 1998 model 4T80-E specs I was looking at, so there should be no compatibility issues there. However, the 4T80-E (at least in 1998) does NOT have a TCC release switch which the 3800 PCM is going to be looking for. I think you can use some sort of relay circuit or equiv. to produce this signal and just tie it in with the TCC solenoid output from the PCM so the PCM will see the TCC release switch signal as "released" when the TCC solenoid is not activated.

The 2-3 shift solenoid in the 4T80-E works oppositely as it does in 4T65-E applications (ie: it is off in 1st and 2nd gear, and is turned ON in 3rd and 4th gears); so the logic of this solenoid is reversed compared to the 4T65-E. So you would need to either build a transistorized circuit or use a relay to reverse the logic/operation of the 2-3 solenoid control output coming from the 3800 PCM. This should be easy to work around.

The pressure control solenoid used in the 4T80-E is designed to work on a fixed frequency signal of 614hz (at least according to the 1998 model year info in the GM service manual). According to the same year service manual information for the 4T65-E, the PCS used in these transmissions is designed to work on a fixed frequency of 292.5hz, which is about 1/2 the frequency of what the PCS in the 4T80-E is going to be wanting. PCM-controlled electrical current flow thru the solenoid's windings determines line pressure, not frequency. So there may not be any issues running the 4T80-E's PCS at 1/2 the frequency it is designed for...

-ryan

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OVERKILL IS UNDERRATED

Custom GM OBD1 & OBD2 Tuning | Engine Conversions & more | www.gmtuners.com

[This message has been edited by Darth Fiero (edited 04-18-2011).]