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Converter?

PostPosted: 02 Apr 2008 14:10
by Linka
Hi!

Can anybody help me identify this converter? I have the numbers which is: 45291. I only know it is 10" converter. So if anyone could recomed a good site or something that will tell me what converter it is.

/Mikael

PostPosted: 02 Apr 2008 14:53
by dave-r
The only one I can find on the internet is for a M6 tank!

PostPosted: 02 Apr 2008 15:00
by Linka
Strange! :roll: It would be fun to know the stall speed etc ....

PostPosted: 02 Apr 2008 15:04
by dave-r
Well a 10-inch is probably going to be around 3000-3500rpm stall in a 440 just by the nature of the beast. Lower stall in a smaller engine.

PostPosted: 02 Apr 2008 15:09
by Linka
If I don´t remember wrong the guy I bought thought it was around 2200-2400. Is this reasonable?

PostPosted: 02 Apr 2008 15:11
by dave-r
It would be in a slant six or 318 at most.

PostPosted: 02 Apr 2008 15:14
by Linka
`Cuz when I tried to figure out what stall I have in my 727 last summer I stepped on the brake and gave it some gas till I did a burnout and I thought the tires made a spinn at about the same rpm... 2200

PostPosted: 02 Apr 2008 15:15
by dave-r
Actually. Even in a 318 it would probably stall at 2800?

PostPosted: 02 Apr 2008 15:34
by Linka
Yeah, but the guy I bought it from thought I had 11" in my 727 at the moment.

PostPosted: 02 Apr 2008 15:48
by dave-r
Hemi and six pack cars had 11" converters I think? I would have to look that up.

PostPosted: 02 Apr 2008 15:53
by dave-r
Yeah. A 727 would have an 11.75 inch converter as standard and a 10.75 inch in the High Performance cars. The Hemi stalled at about 2800 I think?

PostPosted: 02 Apr 2008 19:49
by Jimiboy
When you are in the subject guys, what size does the converter have stock in the 727/ rallye 340 cars Dave?

PostPosted: 02 Apr 2008 20:04
by Linka
How do you measure the converter to see if it really is a 10"? Is it the diameter or?

PostPosted: 03 Apr 2008 7:29
by dave-r
The rallye 340 should have a 10.75 incher same as the other HP engines.

I have a list of all Challenger engine/trans converter combinations somewhere. I will scan it when I get a chance.

Yes. You measure the outside of the converter body for the size. I think? I never thought to actually try that.

PostPosted: 03 Apr 2008 10:10
by Jimiboy
Ok! :thumbsup:


Thanks Dave! :D

PostPosted: 03 Apr 2008 19:06
by dave-r
Not sure how accurate this is and there seems to be some confusion between model year and calendar year?

PostPosted: 03 Apr 2008 20:54
by Linka
Ok, I think I got now. The converter I´m gonna buy is surely a 10.75". I measured it and as I could see I got approx 275mm. Then I converted it to inch and the nearest I came was the 10.75" which is 273.050mm. So I am pretty sure it´s a 10.75" converter I have there. So what would the stall be on that one I think? More than 2200rpm right? I hope it´s nearly 3000rpm.

PostPosted: 03 Apr 2008 21:00
by Jimiboy
Linka wrote:Ok, I think I got now. The converter I´m gonna buy is surely a 10.75". I measured it and as I could see I got approx 275mm. Then I converted it to inch and the nearest I came was the 10.75" which is 273.050mm. So I am pretty sure it´s a 10.75" converter I have there. So what would the stall be on that one I think? More than 2200rpm right? I hope it´s nearly 3000rpm.


2450 rpm from what i can see in the table of Dave's...?

PostPosted: 03 Apr 2008 21:35
by dave-r
Stall speed depends on what torque you are making. The more torque the higher it stalls. hence stall speed is lower in small blocks.

PostPosted: 04 Apr 2008 11:01
by Linka
Ok, then I will have to try it later this summer to see what stall I have. Thanx Dave for all the answers! :)

Converter size

PostPosted: 05 Apr 2008 5:21
by transman
From the factory, Chrysler made mainly 2 sizes of converters. An 11 inch unit, and a 12" unit. The 12" unit has a narrow ring gear on it (for sake of discussion cause I'm not a work to measure one) around 1/2". The 11" converter has a wider ring gear of around 1". These converters were used in all applications: everything from the leaning tower of power with a 904 to the big/small blocks with the 727. The hemi to the best of my knowledge is the only big block that had it's own performance converter. We've had at our shop 440 converters from various vehicles, including the 6 pack ones. Internally, (if its the 11" model ) they are identical to any other 11" converter for the 440. The same holds true for the 12" unit.
340' s are the like the hemi. They had their own converter. Chysler performance parts at one time had what they called the "J" converter. I've never seen one, but I've heard that they ranged in size around 10". Others said the converter was a 9.5" converter. They may have had others listed in the performance parts catalog, but I don't have any old performance catalogs anymore.
A 10" converter with a big block should stall around 3200 to 3500 rpm. This is pretty much the industry guide line. Of course, these stall speeds can be increased or decreased by the manufacturer to match the power band, engine design, etc.
In small block form, you should expect to see 2500 to 3000 rpm.
A modified 11" converter should stall around 2600 to 3000 rpm with the big block, and between 2200 to 2600 rpm in a small block application.
Engine design and camshaft power bands have a huge impact on a converters stall speed. Pay very close attention to what the cam maker recommends for converter stall.
In race applications of course there are many other factors to effect the stall speed of any converter; rear axle ratios, tire size, etc. There are no on the shelf race converters made by anyone. As each race car is different, these converters must be custom designed for each specific appication.

The converter in the photo looks like a TCI unit.
Hope this helps.
transman 8)

Converter Stall

PostPosted: 05 Apr 2008 5:35
by transman
Linka.
Try this to see what the stall speed is.
Bring the engine up to around 1500-1600 rpm. Release the brake and nail the throttle. Watch your tach and see what the converter flash stall speed is. :thumbsup:
With good performing engine even the smallest converter will cause the rear tires to break loose if you just try to foot brake it. For the converter to reach it's designed stall speed you must prevent the rear wheels from turning, and just using the brakes won't do it. A trans-brake of course is the ultimate answer but they're no fun on the street. :s023:

transman 8)

PostPosted: 05 Apr 2008 8:41
by ianandjess
gday while we're talking tourque converters can anyone tell me from experience how streetable or unstreetable the converter that came with my new tranny will be its supposed to be a 4500 rpm stall itll be going behind a 512 ci stroked 440 six pack with moderate workdone i havent decided on a cam yet im still working it out its all a steep learning curve
cheers ian

PostPosted: 05 Apr 2008 12:01
by dave-r
To use that converter you will need a massive camshaft and very low gears in the axle.

PostPosted: 05 Apr 2008 14:04
by ianandjess
thats what i was afraid of it might work out best if i get a 3000 to 3500 stall converter it would be better i think ,i guess if my gears are still to tall ill have to change them begrudgingly , i like to wind cars up on long straights but if i can drive it around town its no good either
ive been looking at cams & i think this may be as good as ill get as ive ordered a set of 440 source stealth heads as well as the 512 stroker kit what do you think dave
http://store.summitracing.com/partdetai ... toview=sku
my 323 rear end probably wont suit it but i dont see much point in going any smaller after the reading ive been doing also its about the closest i can find off the shelf to what eddie recommended
cheers ian

Converter

PostPosted: 05 Apr 2008 14:29
by transman
Ian: A 4500 stall converter is a RACE, not street converter. Great at the drag strip but an absolute bear on the road. Even a 3500 stall converter is not the best for the street if you're going to do a lot of highway driving. Remember, that at highway speeds, your torque converter must be past it's rated stall speed. In other words, if your engine rpm at 60 miles an hour (for sake of discussion) is 2800rpm and you've got a converter with a stall speed of 3500rpm, the converter is not being efficcent, and is generating ecessive heat that will lead to transmission failure, and excessive heat kills automatic transmissions more than anything else.
You can figure out your highway speed at a given mile per hour by using the calculator at www.ringpinion.com This is the website for Randy's Ring and Pinion. Put in your rear axle ratio, tire height, and highway speed in MPH and it calculates your engine rpm at that speed. :thumbsup:
A man much wiser than me in the high performance game once told me that for the engine to perform at its best, it must hand shake with the torque converter that must handshake with the rear axle ratio. Only when all these componets are working together will you have a well performing vehicle.

transman 8)

PostPosted: 05 Apr 2008 14:48
by Jimiboy
Hope you don't mind me asking. Is there any difference between the stock converter that seems to stall at 2450 refering to the table Dave showed us, and buy another converter that stalls about the same? Like this from Hughes Engines for an example(?)
http://store.summitracing.com/partdetai ... toview=sku
Will it stall the same then? Or is it better converters in other comparison?

I hope you get my thought/question right? :roll:

(I did not have that experience, and did not know the stall was that high really in my stock converter..)

PostPosted: 05 Apr 2008 15:16
by dave-r
The stall speed Chrysler states in its manuals reflects what the aproximate stall speed should be for that converter on that engine.

Aftermarket convertors are for all kinds of engines so usually they state what the stall speed would be on an average warmed over 350 chevy.

If you are lucky they will give you two ratings. One for "small blocks" and one for "big blocks".

But these are just aproximate figures.

Let me say again, as I have said many times over, the actual stall speed of ANY converter is determined by the amount of torque produced by the engine.
However, in general, the smaller the diameter of the converter the higher it will stall.

Example. If a converter stalled at 3200rpm in my 440 car and I sold it to someone else with a 440 but his had a smaller cam. The same converter might stall at 2900 in his car.

If he then sold the converter to a guy with a 500 inch stroker then that same converter might stall at 3500rpm.

Now I just made those figures up for illustration so don't think I am saying that is exactly what will happen but i hope it explains to you what this is all about.

PostPosted: 05 Apr 2008 15:45
by Jimiboy
Okey, thanks Dave! Too bad that there are no figures you can thrust really then, when getting a new converter. I can only try, and see what happens(?) :s013:

PostPosted: 05 Apr 2008 18:30
by dave-r
You are taking a chance with a used converter.
But if buying new then a good manufacturer (such as TCS that Transman works for) will ask you the spec of your engine and axle gears etc. That way they can sort you out one that will work the best for your combo.


Remember this simple rule though. The bigger the cam you have, the more stall speed, and the lower the axle gear you need.