If you get a converter from a reputable company like FTI, PTC, Coan, Ultimate Converters etc, they will spec the converter and stall ratio for your combo.

The car will drive great around town and feel pretty similar to stock, until you mash the pedal, then it will loosen up as it should based on the torque its seeing and the weight its pulling, as wheel speed increases, the converter will tighten up.

Actual "stall" speed / flash rpm really won't effect the driveability if the converter is built right.

The FTI I had in my C5Z would flash to 5200... it would go 5500 on the trans brake, yet driving around town it barely felt looser then stock, at least until about 1/2 throttle.

My 71' has a custom 10" converter built by a local trans guy, its a "tight 10" meaning he built it a little on the tight side for my combo. This thing literally feels like a stock converter with maybe a few hundred rpm more stall (say an 1800) when driving around town. This is as close to a stock converter feel as I think you can get for normal driving, yet it flashes to around 3400 ish at WOT behind my torquey 496. Good enough for 1.50' 60's at 3660lbs. I paid $300 for this one...

If you buy a good stall converter, its not like the old days where they slip all the time, make a bunch of noise and heat, and lose MPH.

I really recommend FTI converters....All my friends are using them, all the fast guys are using them and I had great luck with them with my C5Z. They have a nice custom street converter for $329.


Stay away from JEGs/Summit converters, stay away from B&M, TCI, Boss Hogg etc etc... They'll all drive like **** and be inefficient.


You will need a good plate style transmission cooler for any converter, and its good for the transmission anyway. I run a B&M Super Cooler, plate style....I think its 30,000 GVW....

Another good one is a B&M 70297 with the fan, if you are really idling in traffic a LOT and have a sloppy converter, this is the band aid. But the point is to only have the converter "sloppy" when it needs to be....(WOT).

 

you both seem to miss the point... THE OP DOES NOT HAVE A CUSTOM BUILT CONVERTER!!! HELLO! Nor does he want to change it or put out $1500 for one as suggested . he has what came IN THE CAR ...a low budget high stall ..... I never said it can t be done... get it now?
I recommend he uses a cooler.. do you not ?

 

I recommend an auxiliary cooler on EVERY automatic trans in a performance car.... For $150 you can put a cooler on it, no reason not too...


FWIW, I have a $300 converter, its been in the car for 24k miles, I have over eighty mid 10 sec 1/4 mile passes with it, I live in Houston and drive in 100* ambient temps all summer long, sitting in traffic all the time.... never had any issues with my $300 "3500" converter nor my stock-ish T400 trans.


But yeah, if his "3500" converter is a cheapy from Jegs, then yeah its probably sloppy down low (and up top) and probably will drive like ***.... However with a good trans cooler it will live fine.

We and I suspect he, really have no idea what his converter really is...

Most people have no understanding of what "3500" stall even means....even some converter manufacturers. lol

 

I would tend to say that something is wrong with your tune if you get 6-8 mpg. here are some coolers. I used the big B&M

https://www.summitracing.com/search/...1%2B4294947235

 

B&M Super Cooler installed....for reference.

 

thanks Gcull. I probably exaggerated the gas mileage. I just can't my foot out of the gas. I'll look at the B&M.
Thanks
John

 

Be careful. B&M makes a 3/4" thick one and a 1 1/2" thick one. You want the thinner unit if you are putting it in front of the A/C condensor. It will just clear the hood when opening.

 

True, unless you lay it down flat. It will get fed airflow from the bottom, not block your radiator flow and not hit the hood. (see my pics above)

 

Where were you two years ago when I had to wrestle mine into a vertical position?

 

LOL... Man I posted pics of mine mounted like this about 8 years ago.
But at first I did try to mount it vertically but it was so close to my AC condenser, it was going to hit the hood when I opened it. So I just made staple shaped brackets and mounted it horizontally right over the air holes in the lower chin area in front of the air damn. I figure it will get plenty of air while moving....And at idle, it won't pull air through it unfortunately, but laying flat it, heat should "radiate" vertically off of it.... Its been like this for 24k miles and the trans is still going strong. I've shot the cooler with a laser temp gun before and its never been over 150*.

 

Do you have some 1/4" hardware cloth on the bottom of the unit to act as a stone guard?

 

Well I took the air off. So should it be okay. I mean it wouldn't matter which one I use?
John.

 

This is the one you want:

https://www.summitracing.com/parts/bmm-70274

That’s the one I use and it works great, especially if you have a lot of stall speed.

 

That's the same one I got from Gkull when I bought his Art Carr 700R4. It's a nice cooler.

Mike

 

I would never run a high stall torque converter on the street unless it was a locking torque converter. Excessive oil temperature will harden (and destroy) the piston seals and o-rings along with shortening the lubrication life of the oil. It's about the same as slipping a clutch to gain additional rpm.

 

This is sound advise. Give one of the better converter companies a call
and they will set up you up for what you are doing. You are hearing advise based on old technology that is no longer the case. Things have come a long ways from the vega converter days.

 

That is why you should limit your responses to the threads for people looking to use factory parts only. Some of us like to play with the toys we own. We don't always follow the rules.

 

I have been running a 3,000 stall, NON-LOCK-UP for a decade w/o issues. B&M with cooler, shift kit. No issues.

 

I had the biggest cooler mounted nearly horizontal in the nose. My thoughts concluded that the tranny temps would be the highest level when stopped or at slow speed with minimal air flow. Secondly I didn't want to block air flow to my aluminum radiator

I was into drag racing........ where you are power braking to get the rpm's up and loading the tranny


​​​​so convection air flow was important and like AJ statement about c3s being a bottom air feeder it does get air flow at speed. I had it like that for 20 years in front of powerful engines

 

PLEASE stop posting the bad information on subjects you know nothing about.