file.newsgroup.cars.103647 Maven / Gradle / Ivy
From: [email protected] (Brent Herling)
Subject: Re: Improvements in Automatic Transmissions
>In article <[email protected]>, [email protected] (Shazad Barlas) writes:
>|> I just wanted to know:
>|>
>|> To wheelspin in an auto, you keep the gear in N - gas it - then stick the
>|> gear in D... I've never tried this but am sure it works - but does this screw
>|> up the autobox? We're having a bit of a debate about it here...
>
>
>Ah yes, the neutral slam.
>
>I know that GM tested the old th400's and th350's by shifting from reverse to
>forward gears repeatedly while holding the engine at high rpms. the units hold
>up incredibly well. This is also the recommended technique to "rock" a stuck
>vehicle out of the mud. I think the hydraulics are up to the task, but the
>mechanicals of the driveline may object by breaking something.
>
>$0.02
>
>Ericy
I agree about the durability of the old TH400 trannies from GM. While I
never intentionally slamed my '68 Firebird 400 ci Conv. into gear, I would leave
the trannie in Low (read 1st), grab hold, hit the pedal, and once the tires
grabbed, take off. When I reached about 57-60mph the turbo 400 Auto would
shift to S (read 'super' or 2nd) and leave about 10 to 15 foot of double
stripped rubber on the ground. Most everyone I knew at the time was quite
impressed with 'peeling' out at 60 MPH. The trannie held up just fine.
Motor mounts would last about a year until I tied the motor down with large
chains. Oh yea,FYI: Pontiac 400 ci bored 0.04 over
Large Valve heads
Holley 650 Spread bore
Crain 'BLAZER' cam (don't remember the specs)
PosiTrac, Hooker headers, Dual exhaust
Get this (Conv., leather seats, power windows
power top, AC, Cruise etc.)
Oh yea, I also pulled the 'Cocktail shakers' (weights) from the front
and removed the lead pellet from the accelerator pedal. (Damn US regulations)
OH, HOW I MISS THAT CAR!!!
-- 0-60 under 6.7 sec and about 6 to 14 mpg (well I don't miss the mpg)
-- front wheels 4" off the ground with three quick jabs at the pedal.
-- bent pushrods, stripped rocker studs, every 6-12 months
( I really wonder what kind of rev's I was turning - no tach)
Re: Improvements in Automatic Transmissions
Anyone seen one of these lately? I'd buy it back in a sec!!!
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