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Kustom_dude
05-09-2006, 09:43 AM
I really dig Steve's Shrifter so I had to find a 4L80E.

Now that I have 4L80E It is out a truck its bone stock with less the 30 thousand miles on it. It came with the stock converter.

Now to the million dollar question, what upgrades can I do to it with out having to do a rebuild. Do I get a new torque converter or keep the stock one, shift kit or no shift kit….

Also if any one knows the best place to get a dip stick and such please advise.

Oh ya this thing is super heavy do I need to run big block springs? I have a small block with aluminum heads.

Thanks in advance for the help!!

Kustom_dude

Steve Chryssos
05-09-2006, 12:25 PM
What's up Dude,
Thanks for the kind words. If you tripped over that 4L80E and dug it out of the dirt, it should handle 500HP. You didn't specify engine output, so I'm not sure what mods to recommend. A performance rebuild IS a good idea since you get heavy duty bands, clutches and such. But if the doner vehicle was in good shape, feel free to wear it out and then do a major rebuild. A shift kit is recomended since it build mechanical line pressure. Then you will be able to fine tune the pressure curves with a computer.

Spring swap? It ain't THAT heavy. So no. Just heavy-er. Reply with engine specs and maybe I can be more helpful.

Kustom_dude
05-09-2006, 01:09 PM
Steve,

I have around 475 dynoed hp going into a 71 convertible Chevelle. The car is in a billion parts right now. Money kind of got tight due to all of the other stuff I needed. I could have bought new, just would have had to skemp on a few other parts and I really wanted the shrifter.

If I would have bought a new trany.. well you know the price tag on all of the goodies I need. So instead I went with a stock trany with all of the goodies.

Seemed smart to get a stock trany and do some light mods from every thing I have heard. I will most likely get it rebuilt when its time, but for now I am getting close to havingthe body back on the frame. I want to put a few miles on it and make sure every thing is up to par, then blow it apart for final paint assembly.

Your advise is appreciated.

Kustom_dude

EFI69Cam
05-09-2006, 01:09 PM
I would also check to make sure the converter is not a dual stator. They stall at like 500RPM, and don't work will with any sort of performance engine.
I used a Hughes 2500RPM in mine.

Steve Chryssos
05-09-2006, 03:22 PM
Oh, and for a dipstick, go down to your local GM dealer and get one from an Impala SS. It'll take a little tweaking, but at least you will know that it is measuring accurately.

Edit: It also locks so that it doesn't get blown out at 150mph.
/Steve

71Formula
05-10-2006, 01:35 PM
I am basicly doing the same thing for my 71 Firebird. I ended up just calling my transmission guy to see what he recommended, this innocent question ended up with me having him do a complete high performance build with almost every part swapped out inside, but at $3500 it isn't really the budget option. Now all I need is to find a flexplate strong enough to match the rest of the unit.

I agree with Steve about the springs, the 4L80E only weighs about 40lbs more than the th400, this shouldn't even make a noticable difference.

Summit has a TCI Saturday Night Special Torque Convertor for $410 (TCI-242900) that would probably work well for your car. You could give TCI or Hughes a call and they will spec out a torque convertor specifically for your application.

Good luck with the swap, let us know how it turns out.

Kustom_dude
05-15-2006, 09:17 AM
I was looking at the TCI Saturday Night Special Torque Converter and also the Hughes 2500 Torque Converter.

I am going to do a shift kit. I just don’t know which brand. Any one have any advise on what kit to buy.

The tuff part about swapping this trany is that my frame is a convertible frame and it is boxed so I have to make some tricky extensions for the new cross member to work. I will take some picture and post them in the next few days.

Thanks

Kustom_dude

myclone
05-15-2006, 03:46 PM
I am going to do a shift kit. I just don’t know which brand. Any one have any advise on what kit to buy.

Thanks

Kustom_dude

Transgo HD2 is what I use in the 80E's. Bout $110 once you buy it on line and have it shipped.

BTW, that stock torque converter is where most of you extra weight is coming from IMO (heavy SOBs arent they!). Get a higher stall after market piece in there and the weight will come down quite a bit.

Kustom_dude
05-17-2006, 02:17 PM
Ok im a little confused here on the shift kit choices.

1. 46930-HD2 4L80E Performance REPROGRAMMING KIT.

The other kit says...

2. 46930 4L80E SHIFT KIT valve body kit is designed for installation installed during transmission rebuild. There is NO GASKETS INCLUDED.

So is one for the copmuter and one goes in the trany? Do I need both kits?

Please help,

Kustom_dude

myclone
05-17-2006, 06:51 PM
Ok im a little confused here on the shift kit choices.

1. 46930-HD2 4L80E Performance REPROGRAMMING KIT.

The other kit says...

2. 46930 4L80E SHIFT KIT valve body kit is designed for installation installed during transmission rebuild. There is NO GASKETS INCLUDED.

So is one for the copmuter and one goes in the trany? Do I need both kits?

Please help,

Kustom_dude

Ive ordered ~15 of the below kits and they come with VB gaskets every time. Misprint IMO.

http://www.transmissionpartsusa.com/4L80E_HD2_Performance_Reprogramming_Kit_p/500-046930hd2.htm

You dont have to rebuild the trans to install it. There are a couple of parts that are included with the kit that arent mandatory which require tearing the trans down but like I said (the instructions say this as well) they arent mandatory parts. The kit can be installed just by pulling the pan and valve body.

Just be aware that the Transgo kit directions are HORRIBLY written which means you should definately read through them (more than once if need be) before you pull the pan. The text doesnt really flow from one page to the next real well as in you get to page 5 and find out you need to drill hole in the valve body that you could have done 2 pages ago when you had it disassebled the first time.

Kinda hard to explain but I assure you that youll cuss at least a couple times when you have to go back and take something apart again to do another part of the install. Theyre easy to put in once you do 2 or 3 but the first time is a little bit of a pain.

BTW, you prolly already know this but just in case be sure to replace the front seal (doesnt come in the kit) since murphys law says it will leak if you dont. Might as well replace it since youll have to yank the trans if you skimp out and it leaks when you fire it up.

HTH

Kustom_dude
10-09-2006, 04:11 PM
Ok been a while since I have posted. I have been enjoying my summer with my new toy. I bought a new boat, well not new just new to me.

My car is almost done I finished my frame and now I am ready to put the body back on the frame but I would like to put the motor and trans in first.

I am have bought my shift kit & torque converter for my 4L80e trans. my question is how do I swap or convert my nose cone to work with a regular style yoke? Who are the vendors I can buy from?

Here is a picture off my trans.

Kustom_dude
10-12-2006, 04:47 PM
no love.....:hmm:

Kustom_dude
10-18-2006, 09:47 AM
Ok ... I found out from making a bucnh of calls that Strange Eng. makes a conversion tail shaft peice that works for this set up. It runs about $180

myclone
10-18-2006, 11:22 AM
I just noticed your post so my apologys for not helping out a little.


The 80e needs a slip on yoke to replace the bolt on yoke as youve found out. You can source one from GM by asking for a yoke for a 2500 or 3500 series truck that is short bed regular cab. The short bed regular cabs have a one piece drive shaft so a slip yoke for the trans is used rather than the splined two piece drive shaft in the longer wheel base trucks. Sorry but I dont have a part # handy but any GM parts dept should be able to get it without much trouble.

Heres the rub....(theres always one of those)...the output shaft that uses the bolt on yoke doesnt have the splines cut very deep into the trans since the yoke doesnt move with suspension comression/rebound so you need to pay close attention to the spline engagement when setting up the drive shaft. You dont want the splines on the yoke and output shaft to bottom out before max suspension compression nor do you want the yoke so far out that there is minimal spline engagement.

I set mine up so that at max suspension compression I have about 3/16" before the splines bottom out on the yoke/output shaft which gives me enough spline engagement at ride height that I feel comfortable theres enough meat to handle the power. Thats just my opinion so take it FWIW.

BTW, yeah you can swap in the slip yoke output shaft that has the longer splines but it requires tearing the trans down to do the swap. However, I set up a trans/driveshaft for a twin turbo chevelle with the above method thats making in excess of 1k ftlbs (mild tune:scared: ) and everything is holding togeather so far (except for the owners wallet LOL).

Oh yeah you asked about dip sticks... I went to the local GM dealer and bought one for a pick up truck of the same year as the trans. It was about a mile too long so I cut the tube down and rewelded it to shorten it up and then I cut the dip stick itself down and remarked it. LOKAR makes a nice braided blingady ding ding piece if youre into shiney stuff. Im anti-chrome/bling so I use modified stockers which works out just fine...just be aware that if you try to shorten the stock dip stick by cutting a section out and rewelding it you soon be fishing the broken off end out of the tube. The dipstick is spring steel and doesnt take kindly to welding...it never crossed my mind so I got to drain brand new fluid and drop the pan to get the broken off piece out of the dip stick tube DOH.

HTH

Kustom_dude
10-19-2006, 11:11 AM
Thanks myclone for the help i need to get back on track. i ordered one from strange Eng I hope it works.. i will post back when i get it.

I am working on a 71 chevelle convert the frame is done. powder coated, brakes, blah blah blah ... now its time to make a cross member for the trans bolt the motor and trany into place and put the body back on.

i will post some pics of that in the project up dates

Thanks Kustom_dude