I ran a custom built 66/68 ball bearing turbo from Turbonetics.
It was a slug to get to spool.
Towing, I saw 1200-1400*F in lock up.
Had to drive 75-80 mph, or not locked up, to cool it down to 1000*F
It was a long time ago...technology with tunes has come a long way, as I'm running a BW 66/68/.70 right now, and it spools 10 x faster than the Turbonetics did.
I gotta correct myself here...
When I say slug...there were several issues...stock up pipe collector on a ford 6.0 is garbage.
The adaptor that Turbonetics supplied was not helping the issue get better.
To spool it on the brakes took a careful foot on the go pedal...in my case, I had to actually hear the engine to control the fuel feed to it, otherwise, I just over fuelled it, and nothing happened at all.
When I raced it, it had a 2.8+ second, 60 foot...as wearing a helmet, I couldn't hear what was happening...and over fuelled it again.
Pulling a 8000lbs trailer was a nightmare, as it ran extremely hot unless I was going 80+mph and the revs were above 2200.
On the street, it wasn't bad at all...even with a stock converter....a 22-2500 would have been perfect for it though.
With the one I ran, it wasn't gated at all, and had 80+ psi of drive to 40+psi boost.
Lots of things could have been done to remedy the drive pressure...
And the over fuelling was driver error, as well as tune adjustments...
