Thread: 4t80E trans swap

Sonnax has the fixes for it

Thanks james. Are your 4t80e swaps turned out good with the stock trans or you had to upgrade the trans/converter ?

there is only one.

let me fill ya in.

pontiac jeff got his bonnie rolling with his 80e controlled by an early 4L80 TCM/tunercat from a gm diesel truck.
i did it with the WhippledRiv and sorted out the issues with the oem 65e pcm controlling it just as if it was a 65e, sans TCC (manual was possible but who cares about 3-5% fuel economy when you get 15mpg on e85 with a 2.3l constantly compressing)

for a week we beat the piss out of around the neighborhood, till we finally went on the highway and see if it would upshift...well it downshifted. we were driving it around and flogging the **** out of it starting in 4th gear (the 4th clutches and hub are 3x the size of the 65) and wot "upshifts" to 3rd (hmm why did rpm go up?)

well on the highway it did a near wot downshift to second and we had our answer. that trans lasted a year after that, 100kish 371 fdr 99 aurora trans.

when it did go 4th started to slip above 50% throttle (he liked triple digits alot) then third, changed it out with a 65k mile 99 caddy 3.48 fdr, where he wrecked the car and it sat.
finally fixed it and repainted it, started driving it again where the trans died from the dummy not sealing the inverter setup and saltwater stuck the ckt closed...that took me 10 minutes to figure out...after he killed the trans driving in 4th.

another good trans was installed (none of these cost more than 250$) at which point the car burned to the ground on the way home.
a weldon 2035 will spray 13 gallons of fuel on top of a fire like nuthin.

fuel rail stand bolts backed out and the rail popped off the 160's.he

didnt shutoff the motor when he saw the first backfire/flames.... and the pump drained the tank.

no saving it.
then dave finally got around to shoving one in his gp
i figured it'd be a ****
so we said **** the oem subframes and went solid motor/trans plates.


rip WhippledRiv. we were planning on spraying 200 into it...2 stages...*sigh* guess the 442, your heap, and daves jalopy are it, but i havent had any soft shift issues with my testing so far. in fact, in light of all the trans issues the 65 has and the crap ive dealt with on the TR...i have no doubt the 80e is a better candidate if your not made of money for all the unobtainium parts the 65e requires....

http://youtu.be/loKvzFvR09Q?list=UUc...4buxnbHq7f1ICg

btw some trans comparison pics fer ya on the chainsets thats a 1" gmr next to the 80e's 1 1/16th" chain. i have more pics showing all the bearings vs bushings and the vastly larger bands and clutches. remember these had a heft tow rating in them caddy's. i fell in love with em after seeing how durable the trans was...**** the n*
gm woulda had a tank had the 3800 and ls4 been released with the 80e.
http://s260.photobucket.com/user/JAW...4T60E%20chains

in my eyes the nicest part is that most of the FDR is in the diff, which means your a diff planetary and sun gear away from a 3.71, 3.48 or 3.11 fdr swap to see what the car/motor/cam likes.

btw the aurora conv is probably gonna be way too loose for your stock cams.
id suggest the heavy 4.6 converter from the 3.71 fdr cars.

honestly most of all the info i had was wiped out when the dhp site went down.

the rest is in the whippledRiv's build thread on TCG

My 4t80e is out of a 99 deville. Didnt check the vin for fd ratio yet.
The converter isnt going to be loose. I have 3 turbo choices in case i have trouble with spool off the line.

As for the whipple riv ? You said it lasted a year ? But at what power level and et level was that ?

How abusive was the driver ?

The second trans was being driven stuck in 4th all the time ? And this is why it went ?

these things make plenty of tq as you well know, im not suggesting a tight/low stall converter for spool, im suggesting it since we dont need the tq multiplication on the bottom end, and we need the efficiency up top.

if johnbob's car is a decent comparison (though we were far more radical in some area's) then it was an easy 500+hp and 500+ ftlbs at the wheels, likely far more. than theirs at the time, best et was 12.60 at 111 but the best trap was 118 (liked the 3.48 much more and the N* converter even more,-i think the 3.71 with the aurora converter i have is going in the rear with a 3.11 or more likely a 3.48 front with the high hp N* converter), but everything was in the back half...2.3 60, really ****ty 330 pedalling it to keep out of spin.

we shoulda been in the low 11's if lady luck wasnt against us lol.

btw, we did snap the passenger stub shaft/side gear, but it was on a cold slick night that we shouldnt have even bothered...the car, slip and hooked constantly setting up quite the occilation) before it snapped....

good news is that if this is the weak point of the trans...it handles a 4000lb 3" pulley 2.3L whipple car literally humping the track till it snaps at the 1-2 while at 24psi on 295 mt's at 14psi....it may or may not be the case...the subframe and 2 lobes of theinner tulip do show contact with the cradle...we do not have any way of knowing if this was possibly the cause or resulted from it snapping (the oscillation and the "hey its still a street car bro, lets keep rubber mounts, but im cheap so lets modify chrysler K car inserts to fit the G body mount housings" probably didnt help.

eric was a traveling selesman, at one point he averaged about 150miles a day for a year with the first trans once the 800e swap and controls were sorted out. keep in mind we also were dealing with a whipple that didnt like the bbv (deleted) and other tuning fun with a huge overlap cam and a blower idling at 65kpa.

the wreck and econ downturn didnt help

he was quite abusive, to say he didnt give a **** was an understatement...we were finding good 80e's for pennies and even experimented with a welded diff (fun as hell but broke the axle trying to turn it tight lol. it did still drive though with the welded diff so we got it back tot he garage.

yes, the car sat, and likely since it was driven through 2 winters saltwater got in the relay and ate it, when he started driving it again it filled with water and was cuasing intermittent shifting issues that he thought were other things (ground loop issues since G bodies use the sheetmetal as the primary ground path to the engine) by the time i got up there to look at it the damage was mostly done and he swapped to the third trans...that was doing great (N* converter and 3.71) till it burned.

i have no doubt that the 80e is the th400 of the fwd world, give it a shot, trust me, you dont want the headaches we've dealt with on the TR...we coulda bought like 24 80e's by now....
while yes the 80e has issues, but look at the list of fixes and the costs for the 65 vs the parts for the 80e much like the 400 the 80e just needs a couple things and its good to 500+ all day
the 350 takes a bit more, much like the 65.

put it this way...you next option is an nsx trans or finding a direct mount to a corvette tranaxle, a V drive/live axle or the old toronado tranaxle...

btw the 80e is one reason i love PS headers...they dont need much to clear the trans.

a while back when i talked with dave over the 80e (while he was rebuilding the TR's 65e) i told him id figure out an easy mount setup if he'd take a look at the 80e guts and see what needs work....if yer willing to be a Guinea pig i can ship you plates if you can give me dimensions to fit the oem subframe for a final plate... so i can cut and ship him a set to play with (his mounting is pretty baller though, guy after my own heart lol)

talk to terry at PI, they use the t80e converter parts in other performance converters lol
its time the 80e comes of age and while i picked up the torch from jeff, your ass might as well pull some weight around here lol

i ****ing hate shipping to canada but its for the cause and yer a decent group of rednecks.

we're still gonna woop yer ass, we got 14 years head start lol

you should get some pics of yer heap with some tundra wookies laying on it...

Humm your answers leave me with more questions lol.

Hiw did you only get 2.3 60 foots on 295 mts ? I know it was a ****ty track night but even on cold glueless nights i easily ran 11.3@129mph with 2.0 60 foots on similar tires on the cheAp turbo fwd parts car


Does the 4t80e have a tendency to do one wheel spinning more than the 4t65e-hd ?

Also i discovered something with the twin engine on the stock 4t65-hd. I never killed a trans as a fwd with 2nd gear starts and killed two trans instantly as a rwd. The answer is simple. The traction from the rear engine on sticky mts cause a huge spike load on transmission input shaft and chains. On a fwd the spinning even on a 1.7 60 foot caused the torque peak seen by the trans to be much lower. Because i went straight to 5500rpm + on the torque converter.

With the lack of traction you had even with all that power didnt 100% prove the trans can take the torque from my rear engine. I have a bad feeling i will still be fighting breakage or slipping but we'll see.

that 2.3 was on the quickest pass (12.6) and its that high as i said because a 3.71 fdr 80 and the aurora converter are way too much for the instant tq.

you have no clue how uncontrollable the whipple was. hitting 10+psi at rpm's that even your relativly small turbo cant. id also hazard a guess that your turbo car didnt have subs, amps and even the spare tire in the trunk.
3.71fdr was the wrong gear, the FASTEST pass was with the 3.48fdr and aurora converter but the converter always came on too strong and broke the tires free so i dont think we got much below 2.0.

put that setup into a fiero and it'd rock your socks off...on the front end of a giant buick it was a recipe for smokeshows or slow easy starts till past the 60-100ft

the latest 3.48 trans and N* converter launched craploads better, the motor didnt flash as hard and it was far easier to feather the throttle without dealing with in and out of stall transitions on the looser aurora converter. id bet he coulda pushed that setup much harder

nope, seen far more 65e one legger's... admittedly since you dont see fwd caddy's at the dragstrip...

what you didnt think the rear trans was gonna carry most of the weight?
until the front can pull as hard as the rear off the line your rear is gonna handle the load till the front can claw its way back up to 50%. of course there's gonna be a load spike. the only way you can fix this is with the chassis to keep the nose down (where we are now)

no mater what you do your not gonna fix that problem with the tranny's, thankfully your turbo so you can get a few staged levels of boost to keep the front in check until it has the grip to pull its own weight. probably your only hope with the 65e would be to limit boost/power out back as well.

you want proof it will handle the power? well **** get in line.

i have plenty of proof its craploads stronger than the 65e...unless that 65e is like the TR's and has taken countless years and over 8k$ to get it to handle a measly 600whp in a lightweight fwd regal...

ive seen the same caddy haule an 18ft trailer from chicago to wisconsin 4 times a year for 5+ years, we replaced the motor and the 80e had 170k on it when he traded it in on a new caddy.

when was the last time you saw a GP towing a boat. look at the caddy and gp tow ratings...the caddy trans is made to handle twice the weight....if you dont think its got a better chance than the 65e, then id suggest you start saving cause that 65e build is gonna rape you like it did us (not to mention the trans has been in and outa dozen times now...)

i know you have a shop and a buncha guys you can put on this, but im sure with your low buck build you dont want a trans worth more than the car is....

your also running a 3.29 of 2.93 FDR in the rear....imagine how much easier on the parts it'll be with a 3.71 or even the 3.48...since youll be able to pare back the power while still getting moving.

plenty of pro cars dont use anything near full power off the line, what good is power if all it does is break **** or lose traction....you can often go faster with less.

im just trying to pass on what ive learned from all my work so far. as i said, you get to share the headache now.

HAHAHAHAAH

really though, teardown the transmissions and take pics (i never got around to the pic taking part)

tell me you dont think its stronger...yeah you may still be dealing with breakage and slippage, but at least it cheap...getting harder and harder to find good 65e's nowadays....maybe thats why the prices on good used 65's seem to be almost twice that of the 80e. break one, swap it out, run a 3.48, swap in a 3.11 diff and retest, etc etc

at that point limit the power and keep having fun/sorting **** out...or start dumping money in.

the 4t80e aint no magic cure but it is better.

besides, no more of that pesky line pressure drop on turns/hard accel with the 80e (dry sump trans)

I guess what I'm saying is that even though it's heavier n saps more power you're likely going to be happier with the 4t80 E

so quit being a ***** and join the fun.

have you decided whether you're going to use Daves fix for the PCM or whether you're going to just use an inverter?

Originally Posted by Turbocharged400sbc

I guess what I'm saying is that even though it's heavier n saps more power you're likely going to be happier with the 4t80 E

so quit being a ***** and join the fun.

have you decided whether you're going to use Daves fix for the PCM or whether you're going to just use an inverter?

I went with a Magnashift TCM820. It's can shift via RPM set shift points but downshift is manual through a toggle switch.
So I will only have to shift the front engine manually and the rear engine will shift by itself.

http://www.magnashift.com/magnashift_controllers.html

I wanna go to MS with a gpio trans control

those Chrysler K car mounts don't hold up very well unless you fill them and encase them in 3m window weld urethane

they are s*** loads cheaper than the OEM G n H body mount inserts

Originally Posted by Turbocharged400sbc

they are s*** loads cheaper than the OEM G n H body mount inserts

I'm not just using those mounts. The way I have them installed in terms of total sag we are talking between 1/16 and 1/8 max with the full weight of the setup.
The angle which I set them on make them stiff for holding the trans up and with more give front to back. I'm still running a stock mount engine side just moved the engine forward 1 inch by drilling new holes. I also am running a fourth mount that is stiffer but is just used to keep the trans level on the driver side. It doesn't do anything side to side. On top of that I still have the dog bones up top.
All in all. it is twice as stiff as stock and I made enough clearance around the rack. Huge job, lots of measuring putting the combo back in take it out, do that many times.

But now it is perfectly centered. With all the fab work I have I had to keep everything pretty lined up or else I'd have to refab other parts.

Trans is going into the car tomorrow morning.
We got the trans bolted to the engine.
The flywheel modified to fit. We actually had spacers made to exact specs to match the height of the 4t80e flexplate.
I noticed when test fitting the flexplate would have to flex to mate to the converter.
The spacers were carefully tig welded to be perfectly flush and fit exactly. We also tig welded weight back onto the flexplate after grinding some of counterweight off to fit the four torque converter bolts.

So James what have you done yourself to the flywheel apart from drilling 4 holes ?
Which final drive did you end up using ? I unfortunately have the 3.11, kinda of a waste when you have on a strong fourth on that trans...