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recommend? I have a 289 that we hope to get 300 hp. (for now) I am installing AOD from an 82 Mercury and my question is what size torque converter should I get for this project and where is the best deal. This car might see the strip once a year at the most. Im going to try to get this tranny done next week, while my car is waiting to go to its next body shop visit.
 

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Lots of options here. Number one is whether to go with a lock up converter or not. Most high performance converters avoid the lock up feature.

If you are looking for more punch off the line, a 2400 stall speed converter will give some without sacrificing too much mileage.

I'm building a 5.0 EFI to about 350hp at mid rpm range, and I've decided to use a stock converter in an AOD. While the stock converter stalls at about 1800 with a stock 5.0, I figure it will stall about 2100 with my setup.
 

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While the stock converter stalls at about 1800 with a stock 5.0, I figure it will stall about 2100 with my setup.
I'm not sure I follow that. I know that stall speeds are just general guidelines, but the stall speed is the speed at wich the converter becomes so effecient, that it would stall the engine, if you can hold it still.

It seems to me, that if a converter stalls at 1800 RPMs, it would stall at 1800 RPM's no matter what engine it's behind. I'm not sure how the converter would slip more behind one engine as oppossed to another.
 

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What cam, heads, and rear gears will it be running?

You want the stall speed in the power band, so that the engine can get into that power band quickly, before the transmission bogs it down.

I would recommend a lock-up converter. The lock-up only happens in overdrive. When I put my AOD in several years ago, everything I read said that the non-lockup was better for performance, so that's the route I went. Now that I've been using for several years, driving it daily and racing it a couple times a year, that whole argument doesn't make sense to me.

At the track, you'll never shift into overdrive. A) you don't have time, and B) there is such a huge drop off from 3rd to 4th, it wouldn't be very efficient (you'd be dropping to the bottom of your power band just before crossing the line, instead of "powering through"). So, basically, you use the overdrive when you DON'T WANT performance, such as freeway cruising, and don't use the overdrive when you DO want performance.

It's for that reason, if I were to do it over, I would go with a lock-up.

As it stands, I have a B&M 2400 Holeshot converter (2400 stall speed) with a healthy 289 (9.4:1 compression, 351w heads, Lunati cam, roller rockers, yada, yada) and a 3.50 9" traction-lok rear.
 

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Thanks Johnpro, I almost sent you a personal email. Im not sure the exact details (I can get that in the morning) The cam is more than mild, heads have been worked, and I am going with 3.73 8" traction lock rear. We have been getting everything from summit, is there a beter place to get the converter?
 

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I bought my B&M converter from Summit, along with the B&M Transpack shift kit. I would recommend spending the extra $, though for the TransGo shift kit. I am not all that impressed with the Transpack. It's ok, but not as snappy of shifts as I'd like. The only time I ever hear a tire bark out of my 1-2 shift is at the track, and I've never heard a 2-3 bark. I've talked to others with the Transpack and they said the same thing, yet everyone I've talked to with a TransGo shift kit has loved it (guess there's a reason it's about twice as expensive *LOL*).

You will probably do well with about a 2400 stall, in my unproffesional opinion.

My car runs consistent 14.1's and 14.2's at 100 mph in the 1/4 mile, and gets 20mpg on the freeway.

With the higher stall, you will sacrafice some RPM's on the freeway, and even more so if you go with a non-lockup. At 75mph on the freeway, I'm turning 3k RPMs. I can live with that, though ... oh, 3.50 gears.
 

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If you are going with an AOD, I think the lock up is in the transmission, not the converter. The AOD has a 2 piece input shaft. One shaft is inside the other. That setup is also one of the weak links on an AOD. If you have your trnsmission rebuilt for street/strip performance, the builder will probably want to put in a one piece input shaft, and that will do away with your lockup. On the AODE and the 4R70W the lockup is done with the torque converter. Both of those transmissions are controlled electronically. If you go to http://www.lentechautomatics.com/ or http://www.transmissioncenter.net/aode.htm or http://racetransmissions.com/store/product_info.php/cPath/1_31_143_149/products_id/273 you should see that there is no lockup converter offered for an AOD.
 

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Johnpro's right. Go with the 2400 stall B&M (BMM-40431) and the shiftkit, they're both in stock at Summit, that's where I got mine. $329.95 & $28.88 respectively.
 

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Excuse me, $53.95 for the B&M Transpak (was looking at the shift improver kit).
 

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It seems to me, that if a converter stalls at 1800 RPMs, it would stall at 1800 RPM's no matter what engine it's behind. I'm not sure how the converter would slip more behind one engine as oppossed to another.
I can't speak from experience (unfortunately), but only from what I've read. From TCI's site:

The primary thing we want to remember about torque converter stall speed is that a particular torque converter does not have a "preset from the factory" stall speed but rather its unique design will produce a certain range of stall speeds depending on the amount of load the torque converter is exposed to. This load comes from both the torque produced by the engine and the resistance of the vehicle to move from rest. The higher this combined load the higher stall we will observe from a particular torque converter, and conversely, the lower the load, the lower the stall speed.

But in reading the above, I discovered a wringle in my logic: While my higher output engine (hopefully 425 lb\ft torque) should cause the converter to stall at a higher speed, my 66 will be about 400lbs lighter than the donor GT that supplied the drivetrain. So while I have more torque, I'll also be launching less mass which will probably counteract the higher torque (in regards to the stall speed).

I guess I'll consider a 2400 stall speed converter instead of the stock unit.
 

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Thank you for clearing that up. This has been something that's always been a bit confusing to me, and after doing more research and looking at your links I agree. It appears that Lintech may actually have a lockup converter for an AOD, but it would only be used in THEIR transmission.

Here's a great article that I found.
 

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That's a very good article. But I think they are still doing the lockup in the transmission. Their valve body does some tricks and routes the lockup to the small shaft only in OD instead of 3rd and OD. This lets them use the big shaft for 1st, 2nd, and 3rd. I think the only way you can use a lockup converter is with an electronically controlled transmission. I thought about a 4R70W for my Mach I, but after reading that article, I might look at the AOD again. Wouldn't have to buy the computer to control the transmission, just a TV cable.
 
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