I called B&M 2 times and i got 2 different answers from 4 different people.
Which would you use? $165 vs $240

1970 4 barrel w/Q-jet
350 bored .020 over SMALL BLOCK
10.25 compression
Lift .444
Duration 280
@050 214
2" manifolds with 2.5" dual eshaust
Turbo 350 w/ shift kit
3.31 posi
26.2" tall tires

engine is rated at 350 HP and 380 ftlbs at 3200 rpms

which would you buy for a weekend cruiser that i will be able to get on it once an while. I might go to the strip once just to see if i can run below 14 seconds

I'd get the 2400 IMHO and experience

another vote for the 2400

im using the b&m 2400 in my biscayne, which is similar to your combo except it has less compression(9:1), less cam(266 advertised), 3.55 gears and 27" tires. i drove this combo daily for a few years before parking the car for rust repair, the car always performed very well and was very reliable. this combo surprised alot of unsuspecting people, which i think has alot to do with the converter, since the combo is nothing special and the car is pretty heavy.

My vote is also for the 2400, but I would look into PTC, same price, better converter. Check them out on the web, get the phone and call them.

I'd go with the 2400 but it also depends on your intended usage:

2400rpm converter:

Yours is an L-46 350, fairly similar to an LT-1, isn't it? (albiet less compression and cam) Weren't they known more for screaming rpms rather than torque?

Also with a heavy car like yours with mild 3.31 gears you will need the advantage of the converter.


BUT you should also consider that:

2000rpm converter:

with 26.2 in tires 55-60 mph is about 2300-2550 rpm for you are right on the verge of the 2400's stall, and confortably above it with the 2000. The 2000 rpm converter is gonna be more efficient in until higher speeds.

Since our cars aren't known as fuel-sippers anyways I kind of feel like "whats the point" and just go with whatever works better for the car. I think 2400.

Also I don't really know what type of stall they rate them at (flash stall?) and not sure how that translates into slippage when cruising at that rpm. Rule of thumb is to select a converter that stalls where the engine starts to make hp. That is at least 2400 rpm for that engine, probably a bit higher.

2400. Especially with a 3.31 ring and pinion. My .02.

I think i am gonna go with the 2000.
1. I talked to another "expert" and he said with my cam i should see 2200 from the 2000 and about 2300 from the 2400.
2. a 2000 will create less heat
3. $120 cheaper
4. the 2400 will be at the stall speed.... at speeds i plan on dirving.
I understand it will be slower but...its better than stock and good enough for whos it for

Guy who did my converter said he shoots for 200-400 above the torque peak (or start of the torque line in BBC's). He exlained why, but to be honest I don't recall. I use the radiator cooler and an external cooler, and trans temps are always normal. I'm not sure what the real story is behind cruising @ an RPM before the stall of your converter, or if its just a bit less efficent and generates a bit more heat.

That being said, with the CR and such, go for the 2400. I had a 2000rpm large diam. converter as my 1st one, and it was so tight it would near stall the engine at stop lights pulling through the brakes. This was a 9.6:1 motor, so 2400 might be better for you, and others here have used that converter, and have good tings to say.
matt

This is interesting, because I have been using a 3000 stall 10" behind my 408 motor with 3.73's. This motor seems to be at 3000 RPM all the time when under load in my '69SS. I will be looking to a 2400 (max) converter for the 502 motor. Last 350 I had used a 2600 converter that worked well. For me putting a 2000 stall converter behind a low compression 350 would not be worth the money spent.

For me putting a 2000 stall converter behind a low compression 350 would not be worth the money spent.



amen to that.

I was advised with my 406 and 700r4 to stay with a low stall,which I did for a few reasons. First there is less heat buildup,second I had way more torque than I could hook up anyway even with only 2200 stall,third if I launched like a ProStocker vary often I'd have to second mortgage the house to keep me in transmissions.
That said,if I were you I'd keep the stock converter and spend the same money on some gears.The combination you have isn't that far away from stock,and the stall will only help you on a hard launch,where a gear change will gain you torque advantage in every gear.

I beg to differ
IMHO and experience,a stall convertor also helps provide improved throttle response,due to the fact it gets the engine into the powerband quicker.
I've also seen and experienced a stall convertor swap improve ET more than a gear swap too.
You mention you went with a 2200 stall.You also mention you have a 700R4
They have a steep 1st gear (3.06) vs. a TH350 (2.48)
With that much torque multiplication of your 1st gear,not much stall is needed.
You can't compare your combo (a 406 too) to a TH350 and a mild 350
Also the heat build up "difference" from a 2000 to a 2400 stall is a moot point.
And they are both 12" convertors too.

I beg to differ
IMHO and experience,a stall convertor also helps provide improved throttle response,due to the fact it gets the engine into the powerband quicker.
I've also seen and experienced a stall convertor swap improve ET more than a gear swap too.
You mention you went with a 2200 stall.You also mention you have a 700R4
They have a steep 1st gear (3.06) vs. a TH350 (2.48)
With that much torque multiplication of your 1st gear,not much stall is needed.
You can't compare your combo (a 406 too) to a TH350 and a mild 350
Also the heat build up "difference" from a 2000 to a 2400 stall is a moot point.
And they are both 12" convertors too.
Not exactly apples to apples here I realize,but the combination looks pretty much stock,and he mentioned racing it once just to see what it would do. Not exactly a race car,so why build it like one.You can put 4.11's in Mom's station wagon and it'll be a blast on the street.On the other hand 400 rpms more stall would't hurt,but for the money....I'd go for the gears

Not exactly a race car,so why build it like one.You can put 4.11's in Mom's station wagon and it'll be a blast on the street.

Well, 2400 stall is not a race converter. 2400 is quite mild, and very streetable.

The $75 difference should not be the sticking point, IMO, he should get what's right for the car.

$75 could be applied towards gears, but he won't be likely to be able to outright buy a set for that.

You need a good foundation to build a good car. IMO 2400 is the right choice. 2000 is also not a BAD choice but 2400 will perform better, especially with his combo. I think with his mild gears he will be MUCH better off performance wise with the 2400. It's not like it's going to be slipping massive amounts at cruise speeds, I just thought I would point out 60mph lands close to his stall rpm.

I wish someone had a curve to post, just some sort of guideline, that would show the %slippage of a 2400 stall converter across an rpm range. I suspect there are just too many variables, though.

I bet your 2000 stall converter stalls somewhat higher than that anyways given that you have a 700R4 and a 406.

I'd go 2400,in any case.imo

My 355(xe 268,9.5cr) was much happier with the 2400 as opposed to the 2000,Now,the 402 runs hella better with the 3600 vs. the same 2400.Not just off the line either,the rate of acceleration is quite greater also.Trying to get to the strip to have some #s to compare.Heven't used the 3600 with the 4.56s yet,gonna do the 3.73s for a while,spray it,then swap back later,maybe mid summer.

p.s.-a 3600 stall(or 4.56s) on the street is not for everybody,especially a daily driver.

I would definetly shot for the 2400, We are currently using the 2000 in my buddies car right now and just pulled it out the past weekend due to problems that MadMarv had.

I would go for the 2400, you will be much happier. Have the 2k in a buddies car and it has issues.

I've also seen and experienced a stall convertor swap improve ET more than a gear swap too.

Ditto.

2400 is mild. IMO, too many people go too conservative with converters. In fact, I think 2400 is about right for a 9:1 350 with a STOCK '929' cam. I would not even spend the money swapping converters if I was going to run something smaller than 2400 rpm.

OK......I am getting frustrated!!
I bought the 2000 today ($174)
Since everyone says it causes trouble...(is it the converter or the application?)
should spend the extra 80 bucks for the 2400? All i really want is a something better then stock and take it to the track once just to see what it can do.
Or should i go buy a stock one?
Or different brand?
Coan for an addition 1$70

Brian

I want it to drive normally... and for it to roll from a stop. and when i punch it.. i want it to wake up.

worst case scenario,eat the shipping to send it back,and get the 2400

what about the issue of driving in the speed range of 55-60 and being in the stall range? will the extra 300 rpms be worth it?

I will take back the 2000 today. I will either buy a 2400 or I think I can buy ATI in the same price and stall range.

what about the issue of driving in the speed range of 55-60 and being in the stall range? will the extra 300 rpms be worth it?


I cruise at 3200 @ 70 MPH with 3.31's and a 26" tall tire
I used to have 2.56's
The 2400 worked fine with either gear without excessive slippage on the highway

Sorry to bring up that cruising at stall thing. I really don't know how much it slips at the stall speed under cruise conditions. I just wanted to point out that the converter is not in it's most efficient range.

It's not going to slip huge at that speed with cruise-throttle position.

Even a 2800 stall converter will still idle forward at a traffic light, you won't need to rev your 2400 to move.

2000 isn't much better than stock. If you want a difference you can really feel the 2400 is it. Or hey, how 'bout that 2800?

Think of it this way, if you had posted a poll the results would be pretty overwhelming.

At light throttle steady state cruise conditions, a good 2400 stall converter will be very efficient. I'm not sure I understand where the "don't cruise under stall speed" rule started, but I think people worry a little too much about that. At light throttle and low torque inputs, a converter will not "stall" at 2400 rpm. Read this and remember it: stall is dependent on input torque. Driving along on level ground at steady speed, you are not putting much torque through the converter, so it will couple with minimal slippage.

Look at Mr4speed... He had a 2400 converter with 2.56 gears, and I doubt he made sure to keep it above 75 mph everywhere he went, just so he did not fall below the published stall speed! (well, maybe he did... I am assuming not! ;) :D )

Novadude is right, the stall speed "moves" depending on how much oomph you are putting thru it. A big block in a heavy car will stall higher than a small block in a light one, with the same converter (assuming the big block puts out more hp that is).

I put the B&M Holeshot 2000 in last year and was surprised at the low stall of about 1500RPM. I am not pushing a lot of power but I was still surprised that the car wants to walk so soon. I will be putting in a 2400 as soon as I can afford it, maybe I can find a used one locally. It is a daily summer driver and I occasionally pull a trailer with a 4-wheeler but I do race it at least 5 times a season!

What do u think about using a 2400 with 3.08s? I allways woried it would slip too much on the highway

Ok I bought the 2400 kinda
I bought an ATI 11" converter that will stall around 2300. I bought an ATI because it was only $45 more. And i heard an 11" is better than a 12"