TCC lockup - which scheme would give better performance?

[Bruce Plecan]

-----Original Message-----
From: Roger Heflin <rah at horizon.hit.net>
To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
Date: Saturday, January 09, 1999 2:20 PM
Subject: Re: TCC lockup - which scheme would give better performance?
 Bruce Plecan wrote:
>> From: Roger Heflin <rah at horizon.hit.net>
>> Subject: TCC lockup - which scheme would give better performance?

>> Don't lock the TCC under full throttle!.
>> The TCC is much softer than the other clutches in the tranny to prevent
it
>> from chattering.  I've gone thru 4 or so tranny overhauls in my 700R4.
Last
>> guy said ditch the TCC, and you'll never break it again.  Well put 50,000
>> on it, and it's still alive.  Cording to him what kills the 700's 4L60's
is
>> the
>> TCC fllaking off and contaninating the fluid, and at a microscopic level,
>> getting embedded in the other clutches, and then they fail so like the
3-4
>> clutch problem is really caused by the TCC.  I will admit, that I'm hell
on
>> trannies,
>> with all the calibration testing I was doing, but going to a non-lock up
>> converter was the best tranny money I've spent.  If you don't drive hard
>> often, or mileage is your primary concern ignore the above.
>>   Also, comparing the 700 to the GN 200 isn't a good comapro in my book.
>> The 200 as installed in a stock gn is light years ahead of stock 700, in
>> my opinion.

Let me clarify a point here, while I might be wrong when I refer to GN
I'm addressing the 86-87 Intercooled ones.  I'll in the future to write GNX,
and then everone will be clearer about which ones I refer to.

  Very early in the gn program, it was looked at to haul 4
>> guys with misc hardware at WOT in pursuit situations.  The 700 was
>> never really successful at that, from what I've seen/heard.
>>   Bruce
>
>Do you have any idea what that "chattering" sounds like?

Momentary vibration, sometimes felt, sometimes heard.

 I have a
>high perf aftermarket and it makes odd noises sometimes that might be
>described as chattering.

If strong enough to live at 300 for even a while, it's got harder clutch
linings in it, and it will tend to chatter.

 Also the company that I got the converter
>from makes multiclucth TCC to survive the lockup at WOT.  I wonder if
>the aftermarket torque convertors use a much tougher clutch?

Yes, they have to.   Also, remember all these plates to add area,
probably are adding some weight.  Then also displacing fluid from the
converter, so it's subject to even more heat,  all in all I don't see
any really good answers, and like I said my is living in it's current form.
For the money, and time for replacing converters when they fail to get a .1,
I'd dig some weight out, and worry more about details in tuning.

 I have
>had the aftermarket convertor for most of my cars life (70k or more).

What kind of ET's are you running, and how do you plan on going?.

Bruce
>
> Roger
>