Ron, you were talking about the TC you have, what is the size and stall RPM.

I have just ordered a HD rebuild kit for my 4L60e. I will be rebuilding it over the xmas break and will be needing a TC.

I am thinking of stock stall but these are only available in 12". I have not driven a car with a higher than stock stall (all my performance cars have been manual, except a Merc AMG).

I want good throttle response in gears so I am a bit apprehensive of going higher stall. Most of my track work is going to be circuit sprints not drag racing.

I would be interested in peoples experience.

 

Jaguar used a somewhat high-ish stall speed to begin with, about 2000 rpm.

With some anxiety went to a 2500 stall convertor in my XJS. I was pleased with the result. It did exactly what thought it would do.

Naturally it had a soft-ish feeling a low RPM but it was much less than I anticipated and the overall result was positive.

But I ran the 400 trans in my XJS.

The 4L60 has a fairly aggressive 1st gear, as you know. That alone should go along way in getting the engine into the power band when coming off the line. And in your track driving you'll probably spend almost all of your time well beyond the stall RPM anyway. So, in the end, I'm not sure you'll see much benefit from a higher stall speed.

Cheers
DD

 

Thanks Doug I was thinking going lower stall like 1200 or so but I am not sure. What I do not want is sluggish throttle response. I didn't know the OEM stall was that high.

 

What motor do you have?


I have a 700R4 and recently I upgraded from the stock stall to a 2000RPM stall. I found this was a great improvement. I'd strongly suggest you find out exactly what stall you have now. There should be three letters somewhere on the existing converter and if you google them you can find out the stall you have.


I was interested in changing my stall speed because my car crept badly which effected the refined feel I expected from my Jag. I have a stout SBC 409 motor that needed to idle at 750RPM. My stock converter stalled at 1400 RPM. I upgraded to a Summit Racing 2000 RPM lockup converter and no more creep and I was able to lower the idle to 650RPM. This greatly enhanced the refined feel of my all GM setup. There is a bit more slush box mushiness with the higher stall converter when compared to the stock converter but it's not noticeable above 20 mph. I've got a 3:54 rear end and setup the 700R4 governor to upshift a bit later than stock. I think an 1800 RPM stall converter would be perfect for my torque motor and rear gear and if I ever have occasion to remove the trans again I'll try it. The right converter for you really depends on what engine and mods you have if any.

 

I was assuming '89 XJS V12 in my remarks

Cheers
DD

 

You assumed correct Doug. And thanks I might seriously look at the 2500. With the 4L60 I will be able to lock the converter in 2-4 gears.

Currently it has the stock 5.3l V12. Interestingly I stalled it up on the brake this morning and it went to 2000rpm before spinning the wheels. This is the stock TH400 and converter.

What I do not want is sluggish low rpm throttle response

 

Well, the engine will respond to throttle perfectly well. The car will respond to the transmission just a bit more slowly.

But, you'll get closer to the power band, sooner. So it's a trade-off. As I say, I was pleased with the result.

I still question if you'll even need it with the 4L60, though, but it merits discussion.

What road speeds and RPM range are you planning on working in?

The 4L60 overdrive 4th gear is of no use for track/sprint, and the deep 1st gear won't be useful above 40 mph or so (guessing). That leaves you with 3rd (which is direct, same as the 400) and 2nd (which is like 1.72 or something...same or close to the 400)

Plus, the drop-off at the 1-2 shift is like falling off a cliff. You'll scream to the top of first gear and then hit 2nd at a relatively low road speed....and then there's a long, long climb back into the power band.

Depending on rpm and road speeds you might be better of sticking with the 400 !

Cheers
DD

 

Slight correction

4L60E 1.63 2nd gear 3.06 1st gear
400 1.48 2nd gear 2.48 1st gear

Cheers
DD

 

I would have liked a 4L80e but these are rare here in Aus so I purchased the 4L60 and $1100 for a rebuild kit. Then a Jaguar 4L80 comes up on eBay. I have 3.58 rear gears so at 100km/h with the TH400 it will be spinning at 3200-3500rpm depending on load.

95% of my driving will be road, lots of trips away are planned for next year. I will rebuild the 60 and install it then maybe later if I have problems upgrade to the 80.

I think I will take your lead and go for the 2500.

 

The 4L80E is legendary but you could stick with the 4l60E because there is more aftermarket support for it and you can customize it almost anyway you like. In either case 4 gears with lockup behind that V12 is going to be an upgraded driving experience.


A few things to consider...I think 2500 stall is going to be too much stall. It's going to be a total slush box. The Foot on break & accelerator test isn't an accurate way to determine stall speed.


You could consider an alternative planet set for the 4l60E because the steep 1-2 gear drop is annoying and your 3:58 rear gear will accentuate the drop. The PATC Mega Raptor 6 pinion planet set for the 4L60e is worth a look.
.... 4L80E ...200R4...4L60E...PATC
1st .. 2.48 .... 2.74 .... 3.06 ... 2.66
2nd .. 1.48 .... 1,57 .... 1.63 ... 1.55
3rd .. 1.00 .... 1.00 .... 1.00 ... 1.00
4th .. 0.75 .... 0.67 .... 0.70 ... 0.64


I hope you're going to use an upgraded LT1 AKA Corvette servo, Z pack for the 3-4 forward clutches and upgraded band on your rebuild. This is kind of necessary to make the trans live in applications over 300HP. Also consider an upgraded sun shell and 5 gear planet like the ones used in the 4L65e.

 

Good points.

I, too, see no particular advantage to the 4L80E unless you have a lot more power/torque than a stock 5.3 V12. Among other disadvantages it's quite a bit more parasitic than the 4L60

I almost went for a 4L60 in my XJS but the trans, an overhaul, an adapter kit, and the required upgrades started getting pretty expensive. I was advised by many that a standard configuration '60 would "no way" tolerate the 6500 rpm that a V12 is capable of.

Cheers
DD

 

Yes i'm aware of this. Flash stall is just over 2000 so actual stall will be higher.


I considered this but the cost of the CR gear set and rebuild I can buy a brand new 4L80e for $3800 (found this yesterday talking to a trans guy)


Yes the rebuild kit I bought has Raybestos clutches Kolene Steels, corvette serve, AC Delco 5 pinion rear planet, Beast sunshell wide band and new RI Drum plus all bushes etc

 

That was my logic while my V12 is stock it will be fine with my HD rebuilt 4L60. I have the adapter it came with my 6.0L engine. I was told the 4L60 will take the 6500rpm its the stock converter that will not.

There is a Jaguar 4L80 just come up on eBay here in Aus for $950, just after I bought my rebuild kit (typical). I am considering buying it and modifying the adapter to fit the 5.3L. The 6.0 and 5.3 have different bellhousing castings, and the back of the block is totally different.

 

warrjon most of the info here is spot on, not much i can add!

when i was looking for a different convertor, a talked with a convertor modifier guy!

i told him what i was doing(V12 jag against a 700R4,) i didnt want a lot of slippage at any speed, and i wanted light rotating weight,quicker response!

he made up from a GM 10" convertor using the insides of a 400 convertor, it stalls(foot brake) at around 2200rpm then tires start to slide,(no lock up clutch) works out perfect driving in slow traffic or fast hi-way cruising , no slip at hi-way speeds, not noticable!

goota go suppers on the table she says!!:LOL

 

True that you need a TC built for that RPM no matter what trans you're running.

What I was told by a number of people is that nothing inside a standard '60 is balanced for anything over about 5500 rpm and that (as I recall) a couple of the key components (clutch drums...?) were simply stamped steel....something like that?

Whatever it was, it was enough to scare me off. And these were not people who were in a position to sell me anything.

<shrug>

I'm not an authority on the subject (as you can tell). But you might wanna get a few different opinions from those who are.

Speaking of convertors, and FWIW, I got mine from TCI. They're on the web. They were very helpful and accomodating. And rather proud of what they were selling, if you get what I mean


Cheers
DD