Hey guys. Besides the 9" being more lightweight, what's the difference between the two? I'm assuming you can tighten up a 9" to hold more power? My current setup has a 12", 2400 stall. I'm going to be rebuilding the trans, so I'm wondering if I should be switching that out as well.

Definetly a size difference! I've been using 9"

To answer your question, This is what I have been told. Inside the converter there are vanes, much like a fan blade, but it drives the fluid. When spinning, they are pushing the fluid, and of course, the faster they spin the more pressure its building to move the car. Well with a factory converter, the motor can usually spin it up to 1400 rpms before it is maxed to the point that the motor can not spin it any more. With your converter, it goes approximately 2400 rpms. The way they got the stall higher, is the fins are at less of an angle. The trade off is more slipage at part throttle vs a stock converter.
Now with a 9in converter, they can keep the fins at a higher angle, but due to it being smaller, it will stall up higher, ie 2400 3000 or whatever you buy. But because it does have the higher angle it will offer better part throttle response then the bigger converter will.
So, all other things being equal, a 9in 2400 converter will have better street manners then a 12in. 2400 converter.
The disadvantage to the smaller converter is it will heat up quicker then the bigger one. To overcome that put a good cooler on the car.
Everything else aside, making the power you are, I would move up from the 12 in and go 9 and look for ones with anti balloon plates etc. to keep together with your hp.

Awesome explanation. Thanks!

And because it has less weight ( like putting lighter flywheel in a man car ) it spins up faster off the line ;
just watch your redline come up real fast

Hey guys. Just an update. The trans is being rebuilt right now. The shop that is doing it suggested upgrading as well. He has either a 10" billet or just standard 10" converters. He said that the performance would be idential although the billet has a bigger lock up converter clutch that is twice as wide as the standard which may make it last longer. The cost difference is $300 between the two ($400 vs $700). Anyone know anything about this stuff?

I'd spend the extra $300 for the improved lockup clutch - but that's me. I can easily put on 25K a year, so the extra durability is worth it to me.

Please do yourself a big favor, Call Yank converters. They are great bunch and very helpful. I have ran their converters for years and never any trouble. I have one in my truck right now.

http://www.converter.cc/

My .02
No such thing as a good cheap converter.
Take advice call the companies and talk to them.
Yank and Vigilanti are names you never hear people put down.
Try and ride in a couple of cars with what ever you want to go with.
You don't want something with that agravates you in you daily driver.
The big names will re-stall the converter if you don't like it. It will still cost to have it replaced.

I just put a Vigilante 9.5 inch in mine this weekend. 5 year unconditional warranty with a 2800 stall.

Hey guys. Sorry, I haven't updated my sig in a while. It's been a while since I've been on here since the car has been down for over a year. The car is now a garage queen now that I have another daily driver. My goal is the get it running, run low 10's or 9's on an 18" drag radial and then sell it or part it out. I'm getting married so it's time to go from two cars down to one, unfortunately. In addition, the usual pressures (kids, house, honeymoon) are starting to build up.

I'm going to go with the smaller converter but I'm unsure if I'll go with the billet or not since I'll only be using the car for a short while and more limited street duty. While the other brands are great, I'm leaning toward the local guy so that if I do need it re-stalled, I can just pull it and head over there and drop it off versus shipping it.

An interesting note on the trans rebuild.... while I was at the shop there were some local street racers that run f bodies with 4l60's dropping off one of their transmissions. The owner said that they're putting about 900 hp through them so I'm a believer now. If they're good enough for them and that power level when the money is on the line, then hey, it should be plenty for me.

Did you talk to Pete Kane about a converter. He built one for a friend of mine. Haven't seen him on the forum for a while but he builds good converters shipped to you for $500.

Got a Vigilante 3200 , never looked back
www.converter.com
you will be pleased !

B&M 2400 Holeshot Left -9.5 Inch Precision Industries Vigilante 3200 Right

If youre gonna just drive it some and sell it maybe going with the local guy will work. Billet huh? Nice.
Keep us posted. Nothign wrong with a good 10"

The 9" converters have lower "moment of inertia", which is engineering speak for "it revs faster".

The 12" converters are more durable. Bigger parts last longer. Personally I think 9" converters are for race-only applications. They do tend to run hotter than larger converters, which isn't a problem in a drag car.

I have a 12" Edge converter in my street-only car. Very good quality part with good fit and tolerances. If you have more than 0.100" between your torque converter and your flex plate get a better torque converter. My Edge converter was close to 0.