My '89 'stang LSx

[Atilla the Fun]

A junkyard 500 is cheap and serviceable, no argument there, and if it makes enough torque for him, then good. I can make a 502 equal it at idle, and surpass it all the way to 6500 rpm, but it comes at a serious $ figure. Also, the BBC can go to 638 ci, far past the cad. The bbc also gives many cheap options for MPEFI, rather than being stuck with a Q-Jet or ancient Bosch TBI. Anyway, if he's able to tow uphill in OD, locked, then he has the wrong axle ratio, and would find more mpg when not towing by going to a smaller number axle ratio. If he's running 4.10:1, he could go 3.42:1. Which is available for all rear axles installed in suburbans since 1970. To make the most of a JY cad, the recipe includes slightly larger valves, good porting, headers, Edelbrock's intake, extrude-honed and converted to MPFI, and a custom spec hydraulic roller cam. Early heads require dished pistons, which leads to hot pistons, while later heads take flat-tops, which leads to cracked heads.

[The Dark Side of Will]

Thanks for agreeing with me
For cheap slap it in and go towing engine, the Caddy is tough to beat. This particular engine does have a towing cam in it, but my dad doesn't remember the specs and has probably lost the card.

Yeah, the truck has more gear than it needs. It's got a 3.73 10.5" in a non-floating housing. I wasn't there for it, but my dad just finished a disk brake conversion on the 3.23 10.5" in the 14 bolt full floating housing that was in the previous truck, and installed it. My uncle's towing a car out to Missouri with it this weekend or Monday, so we'll see how it does.

However, the 80 can tow in third gear lockup and the 60 still needs to be unlocked.

[Atilla the Fun]

the 60E can be built to hold 620 ft-lbs of torque, more than any cad needs. And with the right converter, the huge rpm drop upshifting to second ceases to be problematic. I feel that the 80E's OD is too close, in ratio, to it's first gear, the 60 has a wider spread. For the turbo'ed LSx mustang, the '80 has a more suitable first gear, I just wish OD could be changed from .75:1 to .60:1 For your 80, you can get a gearset that replaces the 2.481818:1 first with 2.75???:1, and second goes from 1.481818:1 to 1.567567:1.
As for the pic of my sleeper, I took it as I said I would, but can't upload it right now, I tried.

[The Dark Side of Will]

Towing isn't drag racing. Without the ability to keep the convertor locked, the transmission will cook itself on long hills. Maybe you can get a convertor clutch for the 60 that will handle it, but those are very expensive and at that point it's cheaper to go to an 80. The 80 is designed for it, the 60 isn't.

[Atilla the Fun]

GM intends for either trans to tow uphill with the converter unlocked, that's what the converter clutch itself, the input shaft, and the hydraulics are designed for. You do need to add a B&M SuperCooler, Best to get their biggest one and bypass the GM one in the radiator. I did this back in '95, towing 17,500 pounds with a stock '94 4L60E. Plus the pickup was another 6000+ pounds. That's past what that trans was rated for, but I put 14x,xxx miles on that truck before trading it in. Trip after trip, from Arkansas to SLC, the trans survived. And the converter was not locked when going up any hill. Now, if you want to try it, Yank and others can make a converter with a clutch that will hold, but then the input shaft becomes the weak link, and while there is an upgrade, it's about as much $ as a new 4L85E-HD. I hate to get into arguments, but I more hate for people to have "facts" that aren't factual.

[The Dark Side of Will]

I'm glad you got one that was built on payday, but we've had the opposite experience, as noted.
Can't get around the fact that the 60's all the way back to the TH700 have poor cooler circulation in 4th gear unlock. The cooler is supplied through an orifice when unlocked, and through both orifice and convertor clutch piston leakage when locked. Piston leakage is actually significant and a greater flow than what comes through the orifice.
Maybe your extra cooler bandaided that problem.

[Atilla the Fun]

Back in '94, GM was saying to shift from OD to D when towing a trailer, and do all towing in D. Back then, there was no tow/haul button in the tip of the shifter. I will never tow anything in OD with any 200-4R, 700R-4, 4L60E, 4L65E, or 4L70E. Gas is far cheaper than any trans work.