Welcome aboard chris. Ive spent some time on the buick site getting help from you guys on my 200's programing issues. You,ve been very helpfull. The trans is workin like a charm now. We should have a transmission section on this forum too since they are often the subject at hand. Without a trans section the questions get dropped into the general catagories which may be in any of the year based catagories. C1and 2, C3, C4, C5. Considering these vettes have a 50 year history I think this site would benifit from a specific trans section where more of the trans topics could be consolidated. How about it moderators?

 

thanks for the welcome.you car nuts are the reason i go to work everyday (besides my wife child and myself).it would be a pleasure to assist in a trans tech forum and help out.hope to see it materialize.to answer some of the qs about rebuilding a trans by the average guy its hard to give an answer without knowing the person in question. i will say that more of the people that have posed this q to me were able to do it sucessfully than those who werent.a 700r4 is alot easier to do than a 2004r for a novice.we are currently working on 2 books and 2 videos for these transmissions and anyone interested in helping out by testing the tech and providing info / pictures most definately should contact me.as far as the loe engine speed in o/d with the 2.87 rear i certainly can say it is definately not a problem as long as the car backshifts / kicksdown as soon as needed as not to overload the overdrive frictions.this is because of the torque convertors torque multiplication in this window of operation can overpower the frictions at a set throttle angle without a backshift.overdriving means output is faster than input and because the front and rear planetary sets are locked in overdrive and the overdive planet is overruning the less speed you turn in engine rpm the less heat you will generate.hey we have a .75 overdrive planetary for the 2004r out of us maill trucks with overdrive.this helps overcome too low cruise rpm in o/d with tall tires or being below the powerband causing lugging with certain engine combinations.


[Modified by CHRIS718, 7:00 PM 8/5/2003]

 

Hey, now THAT's what I call an answer! I'm a soon-to-be returnee to GM/Chevy after a 32 year hiatus - last one was a 67 SS 396 375hp Camaro in 67, of course warmed up some! Sick of fighting w/brand F, and brand M just don't have any neat streetable daily driver muscle cars (also used to have an original 66 Hemi back in the good old days!). ANYWAY, the reason I asked is because I've researched and tried to educate myself on the trans issue, and noted the big ratio spread with the 700. Calculating all that stuff out, I see that first is lower with a 700 and 3:08's than a 200 with 3:23's (and I don't seem to see any 3:23's or even 3:36's available for Dana 36's??). SO - wanting to keep good hiway gears yet have a good stoplight blast - - (this old man ain't dead yet ;-)

About settled on a 383 LT1 with AFR 190 LT1 heads, about a 320/low 500 Comp Cam roller, 2200 to 2500 rpm stall, and (don't shoot me here!) a GM dual plane LT1 intake converted to efi to enhance low and mid-range torque. GM's ad says it ads 30 lb ft on a stock 350 LT1. I've read a number of dyno tests w/383's with those heads, and cams in that range or slightly larger, mostly with RPM Air Gaps that put out horrendous torque (like up to 440 at 2500) and peak near 500 lbs around 4000, with also near 500 hp at just a tad over 5000, so thought that surely ought to make a 3400 lb 82 scoot even with the wide gear spread. I've rebuilt and hopped my share of brand F (HATE those AOD's!) and brand M auto's, and don't see that either of these would be anything too tough to build and update with the available tough parts.

And, yes, I'll sure contact you when I pull the trigger! Never have gotten into what turns when to that degree in the GM's (last one I did was a TH350), and am always interested to learn more about what makes things tick and what is the most efficient.

 

Chris,
Thanks for the informative reply. It's also given me a better understanding of what's going on in the trans (if I've got an idea of how things work then there's less chance of me breaking them :D ).
A separate forum for transmissions is a great idea.
:cheers:

 

Guys, I can only speak for the 1995 Chevy Caprice. Oh, and equipped with the full police package, which included the Corvette LT-1, "Ultra Low 1st Gear" 700R4(according to the window sticker), a 3:73 rear end, and heavy duty everything.

In one year, I put 35k city/highway/pursuit miles on mine and never had a problem with the tranny. Maintenance consisted of a tranny fluid/filter change. Period.

I miss that car -- the "Ultra Low 1st Gear" would smoke the tires every time, something the Crown Vic can only dream of doing...

 

Question for CHRIS718: I live in the rolling country-side of SW Pa., and do a lot of 'scenic-driving' at 40-50 MPH (1000-1200 RPM in OD/lock-up) on 2-lanes in my Vette (see sig). Quite often, the Cross-Fire 'lugs & chugs', so I've been driving around in 3rd Gear (1:1), which raises the RPM to 1400-1700. It just 'feels' better, and it doesn't 'lug & chug' (2.87s & 27" tall tires DO that!). My question is; am I 'hurting' the 700R4, or ANYTHING ELSE, in the drive-train, by doing this? Once I'm in steady 50 MPH traffic, I click it into 4th/OD again. Additionally, CHRIS718, in the future, I plan to install 3.73s gears; how will THIS affect the 700R4 (besides raising the RPM approx 30%)?

As far as 'serious racing applications', I'd go with a THM400, with the available 2.75:1/1.57:1/1:1 gear-sets (I have TWO THM400s w/ TCI low-gear-sets). I think the THM400, behind a SBC, is damn-near 'indestructible' (you won't come 'home-on-a-hook' from the strip, the gear-spacing is MUCH more desirable, and you'll make one-less shift, good for consistency in 'running-the-number'. As for the heavier weight of the THM400, going fast don't mean SQUAT, if you can't make the next round once eliminations start. Neither of the low-gear/THM400s have EVER crapped-out; I swap 'em every 5 years, whether they NEED it, or not! Just my $.02 worth, and thanks for your insights, CHRIS718..... :chevy

 

Just my .02, I am no longer an advocate of the 700R4. It just can not handle the torque. I'm putting down alot of torque and with nitrous, it can't take the abuse. I know alot of people will not agree, but go with the 4L80 or a TKO.

So far I have put about 300 miles on my 700R4 and it has been to the shop over 5 times for adjusment, valvebody problems, pressure problems, and now lock up problems. This will be my last 700R4 and probably my last automatic. :cuss