Electronic Transmission Control

[Doug Dayson]

Hey Grumpy...

nacelp wrote:
> 
> > The stock HD (Vette/Trans Am/Z-28/Formula etc) 700R4/4L60/4L60E is rated
> at
> > 375 ft/lbs...lesser standard duty 700's (S-10 etc) at 325 ft/lbs...
> 
> CA, HP.  My 325 HP SBC ate several 84 MY versions.

The initial model year(s) were designed for the blazingly powerful 200hp
Cross-Fire 350's...700's were continually updated until mid 88...the latest
version can be identified by a lack of pressure ports on the case...don't
mistake the V8 700's (Chevy Bellhousing Only) with the 6-cyl version
(Universal Bellhousing)...
> 
> > Note that the mid 1988 and later 700R4...4L60...and 4L60E's are
> essentially
> > identical with the exception of the E's electronic controls...
> 
> When I changed to a 89 core, they lasted much longer.

Yep...
> 
> > The aftermarket can add "beef" to the 700 family to approximately 450
> ft/lbs
> > (TCI/B+M)...475ft/lbs (Premier Performance/Toy Shop)...and 500ft/lbs is
> > claimed by Art Carr...
> 
> Again, CA HP.

What the heck is CA, HP?

The factory figure's above are GM's...

If you're implying BS then say "BS"...as far as the aftermarket claims I'll
agree with you regarding the TCI and B+M stuff (I've seen lots of broken
ones)...but the others produce good stuff...stuff that lasts behind cars doing
mid to high10's etc...
 
> > Not sure about the stock 2004R's torque rating except that "stock" it's
> > somewhat less than the "stock" 700 family...remembering that "stock"
> T-Types
> > and GN's aren't that quick...
> 
> Ya, right, but with a little tuning run 12s, and the trannies last in stock
> form.  How many easily tunable 12 sec applications were the 700s used
> in?......

Many...any HP F-Car or Vette can be "easily" tuned
(heads...headers...cam...calibration) to run mid to high 12's...some folks
have even gotten those heavy Impala SS's into the 12's...S-10 V8 conversions too...

And how about the GMC Cyclone...that turbo Blazer thingie..."probably" a AWD
700R4 (it has a different case to mount to the AWD transfer case) in it eh...

Though let's not debate the virtues of Forced Induction vs Natural Aspiration
now...remember that "stock" GN's run low 14's to high 13's...and we all know
how blazingly fast the tweeked ones are!
>
> now a aftermarket 2004R can be built to be
> > similar in torque capability to a aftermarket 700...and the fast GN's etc
> chew
> > them up regularly...
> 
> Try, some more research.  A fast GN is what low 11s high 10s, how much work
> would a 700R take to live in those conditions?......

The same as those modified 200's get...

A small displacement turbo motor that doesn't make it's power until the
turbo's spin up (assuming streetable converters) doesn't hit the trans as hard
at launch either...put either "stock" trans behind a "healthy" 400ci or better
with traction and watch the parts fly...

> There are lots of 500HP Gns doing very well with 200R4s with hardened
> shafts, and a updated converter.
> >
And aftermarket steels and clutches and band etc...and modified servos and
pumps with raised line pressure etc...and blueprinted pump...HD sprags and
over-running clutch etc...either can be built to handle about 500 ft/lbs or
maybe a bit more with traction...anymore than that and either is living on
borrowed time if you hook...

If you're gonna drag race with 500ft/lbs plus of torque regularly on slicks
get preferably a TH-400 or 4L80E...or at least a beefed TH-350...or if you're
light enough a beefed 'Glide...

And back to the original thread of living behind a 300HP 350ci in a "street
driven car"...either member of the 700 family or the 2004R would work fine...

Important Note:...the 700R4 runs hot (not sure about the 2004R...it probably
does too)...if any severe duty (racing...towing etc) is forseen use a
aftermarket external cooler in series after the radiator cooler...

If coming from a TH-400 the install would be easier with a 700R4 as they have
a tail-housing with the rear mount in the almost same place (3/4" farther
back)...the cooler lines will fit...driveshaft will need to be shortened...

If coming from a TH-350 then either...though the driveshaft "should" (measure
in the car) work with the 2004R...but the mount will be in a different place
and the cooler lines will need modifying...

With the 700R4 the driveshaft will need to be shortened...and the mount will
be in different place...but the cooler lines will fit...

Most cars will allow you to slide the trans crossmember around enough to mount
either trans...

For both you'll have to get or fabricate a TV Cable mount at the carb or TB
and modify your shifter gate if you want access to all four forward
gears...and possibly re-route your exhaust if it gets too close to the larger
pans these OD Trannies have...

If a 63 thru 81 Vette...you'll also have to modify the parking brake linkage...

Regards...

Doug
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