AW IR C3

Has anyone on this board worked with the 6L80e in an aftermarket capacity yet, such as swaps, performance rebuilds, tuning, etc?

If so what are your experiences with it and has it come to be a replacement for the 200s, 700s, and 4L series of performance overdrive transmissions?

Also, does anyone have experience with one in a C3?

Note: I'm not talking about the version adapted for the corvette transaxle. Also this is in reference to mild street applications (~600hp or less)

Corey_68

The 6L80E is a massive tranny, will take a considerable about of work for it to fit in the tunnel.

It can be done, just needs some mods to make it work.

Alwyn678

700-R4 is the best 4 speed automatic to me, especially if you are putting 350 + HP. A Great option to replace a TH-400 or a 350.

AW IR C3

I understand the 200 700 and 4L trans are the dominant transmissions out there and people all have their opinions. I am less concerned about what you think about a 700R4 and more concerned about someone who has practical experience with a 6L80e. Thanks anyways.

For all intents, I'll probably start off with a 4L60 to get OD now and look into the 6L over time. However if someone has done most of the leg work on sciencing it out then it may be a more realistic prospect for the first trans for me.

Alwyn678

Wish I had the answer......

mrvette

My '72 had a muncie in it and when adding the 700 at first some 18 years ago, I had to significantly widen the pass side of the tunnel, cut the hump down lo and swing it out a couple inches, glassed it back in and made an access panel to allow get at the cooling lines, etc.....

I switched over to a 200 some years ago, reason was the huge rpm drop just crossing an intersection in traffic, the 200 is more suited for this weight car......and I noted the extra width was still necessary.....

now the issue about having an auto already in the car, I really dunno if there is/was a difference between the stick shift cars and the automatic cars on that point.....

as for the L80 trans, way too heavy and bulky, THAT much I know, tight enough with a 200-700

JimLentz

FYI:

https://www.corvetteforum.com/forums...e-in-a-c3.html

diehrd

I run a 4L80e ..

It was really tight but no cutting required .. I think the 6L would take a lot more to fitting her in and require cutting of the tunnel. I also am not sure there is any benefit and have seen where people take it out in favor of the 4L80e because of how robust the 4L80e is ..

AW IR C3

Thanks for finding that. I searched earlier and missed it.

As with a lot of these threads its mostly useless information but at least I know of someone who is working on it. Thanks

This car won't have more than 500 horse anytime in the near future. I think the 6L would be capable of that. Chances are though that I'll leave it be around 300-350. If I were talking even 550-600 horse though I wouldn't consider it a viable option. No need for more gears with that much torque.

68blvert

The only experience I have with the 6L80 is in full size trucks. It is a massive trans. probably weighs around 300 pounds. First gear is utterly useless in a lightweight vehicle. First gear is somewhere around 4 to 1 with second gear around 2.5 to 1. Has an almost 50% drop between first and second. You would also need a stand alone control module. It is a total control electronic trans. The trans control module is part of the valve solenoid assembly and is NOT serviced separately. Expensive sob when they die. The tcm is controlled by the pcm. Hence the need for stand alone controller. Can be done but won't be cheap or easy. At least with the 4L80 you can use the stand alone tcm that was used with the old 6.2 turbo diesel.

mrvette

My '72 was a 4 speed muncie and 336 rear, I shifted it from 2nd to 4th up in the city of Wash DC region.....at 80 mph poor L48 with FI was getting 24 mpg on I 95 to Florida and back....turning 4 grand all the way....

down here in Florida the shifting point is needing a overdrive.....but stick shift overdrives ran some 5 grand or better some 18 years ago.....

so the trick was to get overdrive on a more affordable basis, that finally sorted through a 700 and into a 200 4r auto....still keeping the small brake pedal, which they look at the hurst stick shift lever and the pattern on the console, and everyone questions about that .....

and I can not figgure out for HELL, why anyone needs a 6 speed automatic trans in other than an 18 wheeler....it's BS, you gotta know the clutches don't have the room or thickness/diameter for so many gears....stupid already....

WTF is a TORQUE converter FOR???

with my 200 and the 336 rear, I can turn the street tires at will....anything more is silly.....

and why add weight?? it's supposed to be a 'sports' car, not a truck.....

AW IR C3

Man, I must be having a long day because I think that was all gibberish?


__________

Side note: I'll be postponing any thoughts about the 6L for some time yet. I just priced out everything to get an EZ efi on this bad boy and that's gonna break me. Looks like I'll just work with the 4L60e.

diehrd

I have a year old EZ EFI I am going to list for sale .. PM me ..

Zip Corvettes

YES YES YES
I guess I should have included this subject in my alerts
We are deep in the process of making a kit for this. Our 76 test car has had it in there for two years now. The 6L80 is an awesome transmission set up. You will not believe the performance gain from just the swap. We drove the car to Carlisle averaging about 24 miles to the gallon. That was with the car running 70+ the whole time. I am waiting on two brackets to be made in production and the kit will be available with or without a new 6L80. We have all the controls for it and several options for gauges that I have not completely solidified yet. Exhaust will be a small issue, if you would like to run the stock exhaust you can use the stock crossmember but if you want dual exhaust you will have to wait for our custom crossmember.

jim2527

How much tunnel/firewall modification?

Zip Corvettes

None

JimLentz

AW IR C3

That is truely exciting news. I will be in touch. Have a phone number?

Zip Corvettes

Of course

Zip Products, Inc
800-962-9632 ext 256
I'm Justin at ext 256. If you are close you are welcome to come drive our 76 with the 6L80 in it.
It completely changed my attitude towards our 76. This car was nervous at 60mph, it has a 290HP crate engine in it.
Once the trans was in it, on the first day I was riding with the calibration engineer in it and we were doing 90 which I didn't even think the car would go that fast. You can cruise easily at 70 and pull out and pass. It is fun to drive now. Don't get me wrong on 70's Corvette's I have had plenty of them and have a 75 now but none of them drive as good as this car now.

hugie82

I was going to do one in my SS Silverado and the controller alone was well over a grand. That was enough for me to stick with a built 4L65 with the beefed up parts from monster transmission.