blownup98

i know this was talked about before but im looking for a trans for my ls1.. Im debating between 400 or a 4l80e.. I know you need to get somethings to change to a 400,, does anyone know what has to be or if anything when going to the 4l80e? like crossmember,electrical plug etc? also i always liked 400 because of their strength,, are the 4l80e as strong? see the main reason im thinking about a 4l80e is i want my speedo and everything else to work,, i dont want to put a shifter in the car.. I had few cars with 400 trans in them and i needed to change everything over and nothing worked...Now the main question is , will the 4l80e if built hold up to a 1200 horsepower car? please let me know what you guys think..

Lethal Injection

There are a couple threads on this site here is two.
https://ls1tech.com/forums/automatic-transmission/254997-4l80e-vs-th400-gv-od.html
https://ls1tech.com/forums/showthrea...ighlight=4l80e

The 4l80 is a good option to keep overdrive and withstand power. I think the stock rating is 800ft. lbs.

Some of the guys here need to tell you about ecu issues.

blownup98

thanks but there so many different people saying diff thing and half of them cant even relate to the question on those posts.. ok mine is a 98,, what crossmember do you use,, the same or for a 400,because i seen in some trends you have to change crossmember,, another thing , some guys are changing over to manuel shift and deleteting the electronics ,, why,, if you have a electronic trans keep it electronic, if not go to the th400,, the main reasonim want this trans is because i dont have to shift it and can have the car looking stock.. what is the tci trans controller.. **** all this stuff i should just go with a dfi...can someone at least tell me what crossmember has to be used..

whitt1

I modified the stock crossmember on my tahoe to accomadate a 4L80E.Basicly the transmission mount is about 7" further back and about an inch lower than on a 4L60E.That being said the length the two transmissions was close enough that I was able to reuse my stock driveshaft,by adding a TH400 output shaft.Speartech can hook you up with wiring and tuning.The actual size of a short 4L80E is almost identical to a TH400 so a TH 400 crossmember might work.You'll also need a crank spacer and a position indicator switch to make everything work.

Lethal Injection

DFI and the TCI controller are two different controllers. F.A.S.T. injection controller is for the engine fuel. The TCI controller is for the trans only. F.A.S.T. must have made the TCI controller.

You need to check here for what year stock ecu will work on the trans. Some do I think.

There will be mod work on your crossmember to make it work or just have a new one made. You must understand that this is a new trans to the performance world, retail that is, so there are few things that just bolt on.

I agree with you on the shifting..... The TCI will let you set shift points. Some people are going to manual shift to save the money on the controller. There is no trans brake out yet for the racers to use. That should change as more people use the trans.

jxaxsxoxn

iTrader: (2)

I have a 4L80E and a few th400's.
I just measured....
4L80E length is 32 1/4"
bellhousing to trans mount is 31"
TH400 length is 29 (short tail(4")
bellhousing to trans mount is 27 3/4"
700R4 is 31" in length.
and 23 1/2" to trans mount.
new 4L60E might be different.
My point is, it's not the same length as the th400, the driveshaft might work with the right yoke.
I have no plans on doing the swap in my camaro but I can give some measurements for the transmissions.

jxaxsxoxn

iTrader: (2)

Keep in mind most '80's and '90's th400's were the long tail versions with the small yoke. Most camaro swaps use the short tail.
4L80E's come in two lengths one is normal, the other has a parking brake on the tail, the parking brake can be removed and the tail housing changed but the regular yoke won't go in all the way because of the machining on the output shaft so it ends up being about 3/4" longer.

blownup98

wow so by the way it looks neither the crossmember from the 4l60e nor the th400 trans will work on the 4l80e..does anyone know of a company that makes them,, id just go buy one,, i dont want to just fabricate something considering my horsepower..also does anyone know or is using that fast dfi set-up..does that control the trans and is it compatible to the 4l80e? also someone on here said you need a crank spacer and a position indicator switch ,does anyone know if any company out there makes that,, and onemore thing if i use that fast dfi do i still need the tci trans controller or should the dfi take care of everything? please let me know guys, i always changed it over to th400 and never did this conversion before..

Lethal Injection

I use the F.A.S.T. for my car. It does not control the trans. I hear that Big Stuff 3 has that option.You could check with them. I will be using the TCI controller. It was shipped Tuesday, should have it monday.

Have you did a search thru google for the trans companies? That could help you find the parts for your car. There is no reason not to fab a crossmember no matter what your HP. 1/2 day at a welding shop and you have what you need. They use a welder just like a crossmember company you buy one from would.

whitt1

The spacer and longer bolts are from a 2001 or later truck with 6.0 and 4L80E.The position indicator switch from the same truck will work.If you are serious about making the swap,buy a used transmission that has all the forementioned parts and use the transmission as a core.Most builders will charge you a $1000 core charge and you'll save $3-400 in parts you don't have to buy from the dealer.

blownup98

what i mean about making your own crossmemer of even at the weld shop is they need exact fitting or the car there,, my car is on jackstands with no rear end and isnt going anywhere,, thats why id rather buy one that is sized .. i dont care if it costs $50-$100 more,, but at least ill know it will bolt right up thats why i want to buy it done..

thanks about the info for the trans,, ill pick one up at junkyard and go fromt here,, also where do i find a fast dfi,, ive been looking on the net and am having a hard time findong it.. thanks guys..

Lethal Injection

You will be better off with the Big Suff 3, unless F.A.S.T. gets there new one out.

blownup98

what company makes it or do you have a number where i can call and get some prices for the big suff 3? also is that like a dfi and will it control motor and trans?

jxaxsxoxn

iTrader: (2)

If you're good at measuring and drawing there is no reason you can't bolt the trans up and draw up plans for the cross member.

Not knowing how much you know about these transmissions I will tell you this on buying a used one.
Don't get one older than '91 the design sucks. Try to find at least a '94 or newer. The best are '97 and up. I'm not sure if all have provisions for the position indicator switch, it needs to bolt to the case, and it needs a longer manual shaft (which can be changed).
The easiest way to ID a '97 and up is by the cooler lines, you want them to be the snap in type with one towards the front and one towards the rear. This indicates the trans has the latest factory lube improvements. The older years have cooler lines closer together towards the front.
Also on the passenger side should be a tag held on by one rivet, stamped almost right under the rivet will be the two digit year.

If you have it built be sure they use a sonnax pressure limiting boost valve, these transmissions are known for cracking cases due to high line pressure and cross leaks. I've seen the pressure in my '98 past 500 PSI, it broke the reverse servo with only 60,000 miles on it.
You might want to consider a guaranteed rebuildable core. A transmission guy showed me a 4L80E case that was bought as a core but had a crack in the worm tracks where the fluid goes for reverse, this can't be fixed.

Also grab the converter if it's included in the price, if you don't need it a converter shop will pay at least $40 for it.

blownup98

thanks alot for your help,,

does anyone know where i can find the fast dfi? also has anyone put one in ? if so ,, how hard was it to install?

Lethal Injection

http://fuelairspark.com/