Thread: Trying to pick a converter

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I,m trying to pick one of these converters all are from FTI.
1. 9.5". 2400-2600 stall
2. 9.5" 2600-2800 stall I,m thinking this one.
3. 9.5". 2800- 3000 stall.
4. 12" 2400-2600 stall.
Car is a 2dr 56 Chevy
3:73 rear gear
27" tire
700r4 trans
L31 vortec 350
Heads have been modified to accommodate higher lift cam.
Cam is a lunati 2008130
Adver. Dur. 278/288
Dur. @ .050 219/229
.503 lift int/exh.
1800-5800
Full length headers
670 street avenger carb.
Has a 2100 stall converter now, very sluggish off the line.
Not alot of experience with torque converters, but I do know I need a higher stall to get this to move quicker off line. My problem is knowing how much more. It,s my street car,. But needs to be fun.

Assuming that the present converter is operational to slip to 2100 (as designed), it should do a pretty good job of moving your heap off the line. Your final drive ratio is 11.41:1 in first gear (3.06 X 3.73), twisting through a 27" tire (with a modicum of engine torque, you should be close to getting some daylight under the left front tire on launch). You may not realize it, but the looser you go on the converter, the farther away you move the car from being streetable and you may just as well begin yanking out the extra seats, bumpers, bumper braces, etc., etc. as well as moving the battery to the extreme right rear of the car, using #2 welding cable from the trunk to the engine bay. Drill a hole in the bumper to mount a good quality master on-off switch (required by drag rules when you remount the battery anywhere other than the stock location. In my opinion, you have a great, streetable combination now, and going looser on the converter will only wreck that.

I'm going to change lanes and suggest that you make other changes to produce additional engine torque before you opt for the looser converter. You may or may not be familiar with ported vacuum versus manifold vacuum. Ported is vacuum taken from ABOVE the throttle plate. Manifold is vacuum taken from BELOW the throttle plate. All of us old guys are familiar with using manifold vacuum because that's the only type that was available to us before the advent of the Federal Government forcing auto manufacturers to clean up their act, beginning in 1967.

What I have in mind for you is a DUI (Davis Unified Ignition) distributor, together with the best plug wires money can buy and routing them away from each other by at least a full inch from the cap to the plugs, using standoffs and/or separators that will not conduct electricity. You will provide all the facts and figures about your combination and the engineers at Performance Distributors in Memphis will dial in your new distributor before shipping it to you. YOWZA, YOWZA. (901) 396-5782. I strongly recommend purchasing direct, not through a speed shop.
https://www.motortrend.com/how-to/16...nition-timing/
Ported vs. Manifold Vacuum
https://www.jalopyjournal.com/forum/...acuum.1103404/
https://bangshift.com/forum/forum/ba...vacuum-advance

By the way, do you have some find of non-slip device in the 3rd member?

This might be a good place to explain to some of the younger members, why most stock cars with have "one-wheel peel" on acceleration, with the left rear providing acceleration while the right rear tire spins and smokes. Here's the story.....A front-motor, rear drive automobile will twist the chassis diagonally on acceleration. The left front and right rear get light, while the right front and left rear get heavy. Of course the proper fix is a limited-slip or lock-up differential, but they are a bit pricey. So, I will outline a different way of getting both rear tires to grip evenly for somewhat less money. Most all manufacturers of tube shocks will also manufacture an air shock, which has an air line affixed so that you can change the rate of resistance in the shock. Remove the stock shock from the right rear only and replace it with an air shock designed for your car. Run the air supply line to a place in the trunk that is easy to get to or mount it outside the car, maybe on the bumper or a bumper bracket. Adjust more and more air pressure into the air shock until stripes from both rear tires are equal in length on the pavement in acceleration mode. When you have the combination correct, the right rear of the car will sit a little higher than the left rear. This is the price you have to pay for better acceleration and using both rear tires to their max. Of course if it were me, I would concoct some hocus-pocus story about the car coming from the factory like that when someone asked about the difference in height left to right.

I gotta agree that deal should be stout already. I'd think the carb is a tad small... R U sure the trans is in good shape?

Just so everyone knows, the # 2 post was made by Richard aka techinspector1'
I asked him to reply to jimbos56 since he has considerable more knowledge on that subject than I do.
Hopefully I can get him back on the forum.

Originally Posted by NTFDAY

Just so everyone knows, the # 2 post was made by Richard aka techinspector1'
I asked him to reply to jimbos56 since he has considerable more knowledge on that subject than I do.
Hopefully I can get him back on the forum.

Don't worry Ken.. we all could tell who it was. LOL.. Tell Richard we said HI!

Originally Posted by 34_40

I gotta agree that deal should be stout already. I'd think the carb is a tad small... R U sure the trans is in good shape?

techibspector1 here, I 100% agree with you. Any self-respecting 350 Chevy with L31 heads that will be streetable needs a 750 carb mounted on a long runner, dual plane, CLOSED intake manifold. DO NOT USE AN AIR GAP INTAKE ON ANYTHING OTHER THAN A 100% DRAG CAR,where the throttle is NOT modulated. By that I mean that there are basically two settings with a drag motor, idle and wide open. Street motors require modulation of throttle position as well as heat in the manifold to help atomize the air/fuel slug going into the motor. Personally, I think Edelbrock should be ashamed of themselves, suggesting that the hot tip for a street motor is the open plenum Air Gap. An Air Gap used on the street will work great in hot weather, but when the weather turns a little chilly, expect the motor to buck and snort because the fuel mixture is not homogenized.

I would choose a Cliff Ruggles 750 Quadrajet mounted on an Edelbrock 2516 or equivalent manifold made by another manufacturer because the price on this manifold is beyond ridiculous. I guess it's the "Marine" description that drives the price up. The description I would look for would include 1. (1500-6500RPM operating range), 2. (Vortec 1996-2002 heads), 3. (Spreadbore carb mount for the Quadrajet).

With this combination dialed in, you'd think you were driving a fuel injected motor.

Correct me if I'm wrong, but there seems to be a post missing from this thread. IIRC, it was made by a somewhat newby refugee from hotrodders.com
My personal opinion is that he would be better served if he returned to that website.

Lots of us go to many websites. Some of these other sites offer things we won't find here. In any event, even the OP was on multiple sites asking for opinions / help... don't seem to get any other input from him either. Oh Well.

Originally Posted by chasracer

Ahhh, my old nemesis.

I see that the admin deleted that post and that's fine with me - I don't think the OP wanted an education on it, he just wanted a few people to okay the one that he already decided upon. That's one reason I didn't bother to repeat my post on it.

And no, I'm not any kind of refugee from some other forum site - I visit a lot of different ones, never know when somebody somewhere might have a good answer or a better idea.

Have a good day!

Hey Chasracer,
I feel the same, if I'm trying to learn answers I really don't care who answers if they're trying to help. When I saw your post disappear I figured it was because you direct linked to the other forum. Too often these days some guys want instant gratification so if they post and no one answers within a minute or two they leave!

Take good care, and stay safe!

Originally Posted by rspears

Hey Chasracer,
I feel the same, if I'm trying to learn answers I really don't care who answers if they're trying to help. When I saw your post disappear I figured it was because you direct linked to the other forum. Too often these days some guys want instant gratification so if they post and no one answers within a minute or two they leave!

Take good care, and stay safe!

I could be wrong, but I think Mr Mustang saw trouble brewing and nipped it in the bud. If I'm wrong I'm sure he will correct me.

Originally Posted by jimbos56

I,m trying to pick one of these converters all are from FTI....Not alot of experience with torque converters, but I do know I need a higher stall to get this to move quicker off line. My problem is knowing how much more. It,s my street car,. But needs to be fun.

Perhaps back on topic and hope that jimbos56 checks back and re-engages. He's been around for 5 years so I expect he will.

I also hope that chasracer will stick around! He posted a couple of years ago looking for help with electrical connectors and thanking someone for the help; and then two days back had a great post about age, heat, humidity and amazing details of his drag racing exploits. I'd like to hear more, but on his thread, not here! I hope the next post here is from jimbos56! Or from MrMustang if he sees the need to weigh in.

I agree with jimbos56 returning as far as chasracer goes that's another story and I'll pass.
I've been around drag racing since 1959 and raced some in the 60's and I've seen many like him, reminds of the two idiots that burned down and got disqualified in the 1st round of Pro Stock last Sunday at Topeka.

I don't see Topeka in the same light as you do Ken. One driver was doing all the talking and you can bet your bottom dollar all the other pro stockers were listening. That driver was tired of the games and said no more! I'll burn it down if I have to but I ain't getting pushed around no more! Stupid? Not hardly, those guys are part of a million dollar operation, they don't get there by being stupid imho. And I'll be willing to wager his crew chief set the tone before they strapped into the car. I think someone grew up this weekend! Again, just my opinion.