Here is what is needed, you can get a case to test all the fitment out while your tranny is being built if you like.

you need 4l80e..preferably 97 up but they can all be modded

converter....some require the crank spacer...some dont. You can get it from GM for 46 bux..much cheaper than any sponsor price i found. I ordered the bolts too ...made it a few bux more.

4l60e to 4l80e harness......speartech or speed-engineering. When you hook up the ISS wires to the pcm, they go to pins 22-23 of the red connector, if you gently take off that red plastic (the part that makes it the RED connecter) the pins slide in VERY easily and you can see how they lock/unlock. The instructions with the harness tell you what wires go wherel....very easy and idiot proof...5 minute deal.

Crossmember...bmr or yank. Yanks has the torque arm mount made on to it.....i had to move it over 1" to give my bmr torque arm clearance between it and my brake/gas lines. I also had to slot the mounting holes for fitment but mine is a prototype so all that will be worked out quickly. Bmr has a crossmember with torque arm mount...prototype as well...I already sent it back to Lee and he will make a few changes for me to try and it should be ready VERY soon as well. You will need to remove the plastic clips holding your brake/gas lines to the tunnel beside the torque arm...2 bolts..30 sec job. You need to do this so you can push the lines around some to clear the torque arm and torque arm mount.

Stock pcm has to be changed to handle the 4l80. Despite what I said earlier, Hptuners does not have a way for you and I to change this in their software. You have to get your file edited...hptuners did mine and Quicksilverados. I think speartech and speed engineering does it as well.

stock tranny lines work....you have to gently bend them to a 90 degree angle. you can cut them and lengthen them with rubber tranny hose. On the rear line i whacked the tunnel for about 15 secs to give the 90 degree line a little room...no biggie.

The wiring harness on the left of the tranny...here is where you need to cut the tunnel a little. There is some bracing where this plug comes out of the tranny and it will hit. you can cut the bracing...like a 2-3" square...once you cut that and remove that piece, under it is the tunnel...beat that in with a hammer...and the plug will nestle right in that area. you dont need to cut into the floor/tunnel area....only that section of bracing. the speartech harness has a piece of black plastic on the end of the plug where the wires come out. You can pull that clip off and it gives you a little more room and that plug/wires will fit up in the tunnel like a glove. As bad as that sounds, it was a 10 minute mod...no kidding.

Your flywheel holes will not line up if you use a stock 4l80e converter, you will need to elongate them with air grinder or something. With a stock converter you will need the crank spacer. With an aftermarket converter made to fit the ls1, you SHOULD not need a spacer and the flywheel holes should line up.

Driveshaft....you are on your own. I have a stock rear and the stock driveshaft will fit. I have to use a 4l80e yoke and trim 1 " off of the YOKE and it will fit perfectly.

If you go full manual valve body, you dont need the harness or to cut the tunnel brace for that plug. If you have a body mount torque arm, you dont need to tweak the brake/gas lines any.

I will update/change this as I see things happen and add pics eventually.

 

we spent more time modding crossmembers and trying to fix the fuel lines and the driveshaft than anything else.....once the crossmembers go public it'll be an easy swap....

Jerry you have to change the name of the torque arm mount to the "Chuck mod"....

 

What is a crank spacer, how big is it and why is it needed (or not)?

Thanks,

Jim

 

nice Jerry, I will be doing this mod sometime soon, will have to get in touch with you about it

 

the crank spacer is needed for converters that arent custom MADE for our ls1 cranks. it lets the converter pilot reach the end of the crank. If you call precision/ fuddle, yank etc and have the converter made for your ls1 car, you wont need the spacer. As far as sized goes, it is not something you can make...you have to buy this piece if you need it.

 

Good gist cablebandit I have already done this swap with a manual valve body trans. I did not have to do any cutting or hammering... I just had a custom crossmember made by a local guy, turned out great. That was the extent of my troubles. This is a very good swap that can handle a lot of power Oh and I went with a Vig 5 disc... supposed to handle 1500 hp on the lock up

 

great post, my 4L80E should be here in a couple of weeks. Im going from 6speed to auto. My concerns now are which shifter to use or maybe getting a used stock ls1 shifter and console.

 

Thanks for the info!

 

What about the lock up feature with the full manual valvebody? Don't you still need electrical input from the computer to lock up the tq converter?

 

my understanding with full manual is that you can do it with a toggle switch...someone else will chime in hopefully who has done it.

 

you are correct.....we wired in a toggle right next to the shifter.......lockup on any gear except first on command

 

what kind of shifters did you guys go with on the manual valve bodies? thats the way I want to go.


thanks,

 

I spoke to a local builder and i asked him about htis swap....

he expressed that the 4l80e might be to heavy of a trans to swap into a f-body. Any replies/comments to this?

The lock-up switch, how/where can/do you hook it to?

This seems to be what im gonna go for, just wanta see all of the posible hickups prior i make my decision.

 

I am running a B&M pro-rachet.......I like it, and it seems to work well. You should be able to use any 4sp compatable shifter, some even use the stock A4 shifter, but it does not have the positive detent, and i wanted to eliminate the possibility of overshooting a gear.

IIRC, the T400 is about 40lbs heavier than the stock 4L60......My 4L80 is about 70lbs heavier than a T400......so figure about 100lbs over a stock A4 trans...... I dont really think it affects anything major, as the weight is centered under the car. does not affect handleing, ect. If the weight is a major concern, you can always cut weight somewhere else.....that is what we did.

 

when i went 4l60e to th-400...both with 9.5 precision converters, i LOST 20#.....dunno how the 4l80e will weigh in. the stock converters for each tranny vary in weight a lOT. I have to call Quicksilverado...he went 4l60e to 4l80e...12" converter to 9" and i think he gained 20#s.

TwnTrboCE has gone high 8s low 9s with a 3900# f-body.....thats proof enuff for me

 

low 9' in a 3900lb f-bopdy? how much is he/she pushing through the 4l80e?

 

I went with the same shifter. It fit under the console great and actually Dutch who I got the idea from Here is a pic...
Rachet shifter

I never wieghed my trans. I know it is heavy BUT it has 4 gears and it will hold Thats all I care about

 

TwnTrboCE is pushing 1200Fwhp

 

With the stock converter on the same scale the truck was 20 lbs heavier. With the 9 1/2 inch converter it is the same 4500# as it was with the 4l60e.

 

I weighed three converters, drained. Stock 4L80E is 64, stock 4L60E is 46, TCI SF for a 4L60E is 30 pounds.

Are you guys using the stock torque converter cover for LS type engines?
It works on all year 4L80E's to make them bolt up using the two engine oil pan bolts.
I think it's worth the extra support but thats just my opinion. This way it would be one bolt short of stock (the top one).