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Discussion Starter #1
Well, the next stage of my build is the Transmission.
I've done a lot of looking into this and decided to go with the 700r4.

I found someone local that is really familiar with the 700r4 and is willing to build me a "Heavy Duty" unit for my Vette. He said he uses the 30 (or 31? I can't remember) spline input shafts, and he said he would use Kevlar clutches for me. I told him I was going to install it into my car with the stock 200hp 305 for a while, until my motor is built. He said he would give me the appropriate TC and when I was done with the motor, he would re-stall my TC for a small fee (about half of a new one).

He did ask me a couple of questions;
How much power am I currently running? (200, of course).
How much will I be running? (about 400hp)
How do I want my TC to lock up?

So, here are my questions;
What size stall would you run on a stock 200hp 305?
What is the redline of a stock 305?
What size stall should I go with once my motor is done?
What way do I want my TC to lock up?
I was thinking of a B&M controller, but wanted your opinions on that subject.
How much is my stock TH350 worth?
It has 84,000 miles on it and works AWESOME!


And if you all are wondering, he's going to charge me about $1000 for the transmission and TC. I'm doing the labor (of course). He is giving me a 12 month/12k mile warranty.

He REALLY wants my TH350 for the core. That's why I'm asking how much its worth.

I'm sure I may be missing a few details, I'll post them as I think of them.

Thanks for the input!
 

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Well, the next stage of my build is the Transmission.
I've done a lot of looking into this and decided to go with the 700r4.

I found someone local that is really familiar with the 700r4 and is willing to build me a "Heavy Duty" unit for my Vette. He said he uses the 3031 is the number. (or 31? I can't remember) spline input shafts, and he said he would use Kevlar clutches for me. I told him I was going to install it into my car with the stock 200hp 305 for a while, until my motor is built. He said he would give me the appropriate TC and when I was done with the motor, he would re-stall my TC for a small fee (about half of a new one).

He did ask me a couple of questions;
How much power am I currently running? (200, of course).
How much will I be running? (about 400hp)
How do I want my TC to lock up?YES. Unless your guy has some magic trick I don't know of (very possible) the convertor lockup is part of keeping the trans cool. And heat is the enemy.

So, here are my questions;
What size stall would you run on a stock 200hp 305?
Dead stock no more than 1000 RPM
What is the redline of a stock 305?It'll go until it dies. I'd try to stay below 6000
What size stall should I go with once my motor is done?
Depends on idle speed, cam choice, and rear axle ratio
What way do I want my TC to lock up?
I was thinking of a B&M controller, but wanted your opinions on that subject.
Nothing wrong with the B&M except price. You can set it up so many different ways it's amazing. Vacuum switch to a pressure switch in the valve body, full manual control, and more.
How much is my stock TH350 worth?
It has 84,000 miles on it and works AWESOME!

A couple of other things- the rear planetary set was the weak one back until 89- use one no earlier than that. The next weak spot is the sun shell. There's one out there called "The Brute". I'm sure it can be broken, but looking at it, you're going to have to work at it. Use the Corvette TV Boost and 3-4 shift and TV valves, or you probably won't get 4th gear at WOT. Trans-Go shift kit.

One of the early problems, besides that rear planetary, was the sun shell. If the TV was adjusted correctly for firm shifts, a good solid 1-2 shift at or near WOT, the splines in that sun shell would spin out. :D


And if you all are wondering, he's going to charge me about $1000 for the transmission and TC. I'm doing the labor (of course). He is giving me a 12 month/12k mile warranty.

He REALLY wants my TH350 for the core. That's why I'm asking how much its worth.

I'm sure I may be missing a few details, I'll post them as I think of them.

Thanks for the input!
I suspect he's got someplace to go with your 350- I'm not too current on the prices, but even a brand new rebuilt can't be much. I have a BOP case 400 I can't give away.
 

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Discussion Starter #3
You'll have to excuse my lack of lingo and terminology here, I've always owned cars with a Man Pedal. So, this is my first Automatic that I'm delving into. Before I drop a grand onto this, I just want to make sure I have all the details iron'd out.

Yes, the TC is definitely going to lock up. I'm looking for driveability and MPG. I was asking "How" should I?
I'm looking for pro's and con's of the different methods. He said he would set it up any way I prefer, vacuum, electric, manually...
I was leaning towards the electric for the ability to be able to unlock/lock up the TC at will PLUS I could set my speed in which it locks up at. Like you said, its amazing how much you can do with it. And, I'm already spending a **** ton of money on this car, whats an extra couple hundred to make my driving experience a little more enjoyable.

So, basically a stock TC for the stock engine? Got it! That's easy :D

Can I really spin this motor 6,000rpms? Seems awfully high for a chocked down CA car. Maybe I should dyno it and just see where the peak power is and shift there?
Then again, I AM going with a new motor, eventually.

New motor plus new TC;
I am going with a full roller late model 350. I'm not sure on what internals I'm going to go with. The heads; probably just some AFR's that have a CARB# on them. A cam that will pass the sniffer. Hedman full length Headers with the AIR hookups, true dual, high flow CATS, X-pipe, Magnaflow SS mufflers. I want to put the largest cam I can fit in there and still be able to pass the sniffer (I hate CA smog laws). I'm not sure what my choices are, but I'll have to cross that bridge when I come to it. One step at a time with this build, and my mind changes constantly.
The rear gears? I just rebuilt the entire rear half of the car, so I had 3.55's put in the back. I like them, it helped with off the line performance a little.

Now, my experience with an Automatic has always been with a "loose" TC. They have always been in C5's and 4th Gen F-body's with H/C builds, Pro-Chargers, So basically LSx's. I really like the Yank 4400 and 4000 Stall TC in those cars! They are really loose up until they lock up (programmable, of course) and when your on the freeway all you have to do is tap the brake to unlock the TC and the car will just take off from there! I swear, that is the most fun I've had with an Automatic is when running a loose, high stall TC!

Yes, I have a B&M external cooler going onto the car plus an electric fan system. I have a '92 Camaro serpentine belt set-up for the car. I will be going with a Transmission gauge, and a deep sump pan with extra capacity and cooling fins on it.

So, use a 1989 or later 700r4? No problem, I'll pay attention to the code on it.
I would love for this thing to shift into 4th gear at WOT! that would be awesome! I'll DEF mention that to him.
I don't want "harsh" shifts, so what level of Trans-Go shift kit should I go with?

Thanks for all the info! I'm glad I asked so I know what to ask him. I'm not looking to abuse the car all that much, it will mainly be a "driver". BUT, its STILL a Corvette :partyon:
I also know it will never be as fast as my Firebird...and I'm ok with that. But I do want it more comfortable to drive then my Firebird, and I think THAT is attainable.

And, I'm glad he's giving me a 1 year warranty! Because I'll have the motor built within that 1 year and then I can REALLY test that transmission before the warranty is out, hahahahaha.
 

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Basically, I'm cheap. I'd wire the lockup with a vacuum switch and a 4th gear pressure switch that closes at 40-45 PSI. That way, it has to have high manifold vacuum (cruise speed), and 40-45 mph in 4th gear. Properly, it gets the power thru the brake lite switch so when you touch the brake, it drops the power to the TC.

No idea if it'll spin to 6ooo. Some do and some don't. Too many variables to even guess. I'd limit it to at the most 6ooo, but more likely somewhere around 5ooo. I've seen BB's come off the showroom floor and make 7ooo too.
 
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