Torque Converter Recommendation

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Twagoneer
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Torque Converter Recommendation

Post by Twagoneer »

I have a 1990 GWagoneer with a 727 trans that I am having a 401 built, 268H cam, 9.5 to 1 compression, Edelbrock Pro Flo 4 F.I. targeting around 350to400hp. Will be running stock 323 rear gearing ratio. This is not going to be drag raced. Just weekend toy for road trips.
Question? What Torque converter do you guys recommend?
Where is the best place to buy one?
What are the advantages of a lock up?
How do I know what I currently have? Lock up or Non Lock Up
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dodgerammit
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Re: Torque Converter Recommendation

Post by dodgerammit »

You probably have non lock up. After pulling trans, look at input shaft. Splines all the way to end=non lock-up. Splines stop about 3/4" from end with small nub protruding=lock up.

I'm going to run a Hughes 501FUEL model (verify part # with them. Basically same as chrysler version 503FUEL, but AMC specific with no ring gear on convertor. Bought it direct through their company.

I am building mine to tow lightly (think small 1500# camper/utility trailer) and for low stall and fuel economy properties for my low end power build of the motor.

Factory, your Jeep will not have 3.23s. It will have 2.73 or 3.31 stock ratios.

Lock up will add a small rpm drop around 45-50 mph for fuel economy. Over time, it typically fails on the 727. Most that have had both prefer the non-lock up. Most have said fuel mileage difference is almost nill.

Non lock up is better for towing from what I've read. It is definitely a simpler design with less issues.
84 Grand Waggy-Radio Flyer (Garnet Red/3M Ebony Metallic woodgrain, with honey interior) AMC 360 :cry: 2004 4.8LS/Advance Adapter/727/242 D44/AMC20 Serehill tailgate and headlight harnesses :fsj: Ongoing thread-viewtopic.php?t=11897

92 Wrangler Islander 4.0/32RH/231 D30/D35 RHD

Topic author
Twagoneer
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Re: Torque Converter Recommendation

Post by Twagoneer »

Thank you, very informative. Just to be clear. Can I install either a lock up or non-lock up converter regardless of what is in there now with out any special modifications or requirements?

rocklaurence
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Re: Torque Converter Recommendation

Post by rocklaurence »

IMO, with the low axle ration I'd go with a TCI Saturday Night Special. It has a stall around 2000 RPM and will allow your motor to reach its torque range better off the line. If you do any towing, you'd likely want to add a Aux trans' cooler. Im going to put one in my shop truck to improve performance while towing. With the tires and gears I have now, it will hit stall around 40 mph around town which is perfect.
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fulsizjeep
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Re: Torque Converter Recommendation

Post by fulsizjeep »

Twagoneer wrote: Thu Apr 09, 2020 4:17 am Thank you, very informative. Just to be clear. Can I install either a lock up or non-lock up converter regardless of what is in there now with out any special modifications or requirements?
No. The 727 lockup version was used in 1980-1982 FSJs. It has a different valve body, input shaft and torque converter than the non lockup. The input shaft for non lockup is 24 spline and lockup is 23 spline.
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itselliott
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Re: Torque Converter Recommendation

Post by itselliott »

Twagoneer wrote: Wed Apr 08, 2020 11:56 am I have a 1990 GWagoneer with a 727 trans that I am having a 401 built, 268H cam, 9.5 to 1 compression, Edelbrock Pro Flo 4 F.I. targeting around 350to400hp. Will be running stock 323 rear gearing ratio. This is not going to be drag raced. Just weekend toy for road trips.
Question? What Torque converter do you guys recommend?
Where is the best place to buy one?
What are the advantages of a lock up?
How do I know what I currently have? Lock up or Non Lock Up
Stock 3:23 gears??? I am aware of 2:73 3:31 3:54 and 3:73 ( J truck)

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Twagoneer
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Re: Torque Converter Recommendation

Post by Twagoneer »

itselliott wrote: Thu Apr 09, 2020 1:01 pm
Twagoneer wrote: Wed Apr 08, 2020 11:56 am I have a 1990 GWagoneer with a 727 trans that I am having a 401 built, 268H cam, 9.5 to 1 compression, Edelbrock Pro Flo 4 F.I. targeting around 350to400hp. Will be running stock 323 rear gearing ratio. This is not going to be drag raced. Just weekend toy for road trips.
Question? What Torque converter do you guys recommend?
Where is the best place to buy one?
What are the advantages of a lock up?
How do I know what I currently have? Lock up or Non Lock Up
Stock 3:23 gears??? I am aware of 2:73 3:31 3:54 and 3:73 ( J truck)
Got it thanks they are 3:31.
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Stuka
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Re: Torque Converter Recommendation

Post by Stuka »

rocklaurence wrote: Thu Apr 09, 2020 4:36 am IMO, with the low axle ration I'd go with a TCI Saturday Night Special. It has a stall around 2000 RPM and will allow your motor to reach its torque range better off the line. If you do any towing, you'd likely want to add a Aux trans' cooler. Im going to put one in my shop truck to improve performance while towing. With the tires and gears I have now, it will hit stall around 40 mph around town which is perfect.
The problem with a higher stall is he will run more RPM on the HWY, and will put more load on the cooling system. The cam he has selected really does not require a higher stall than stock.

It would pick up off the line acceleration by letting it hit a higher RPM before it grabs. But, it will not impact the ramp speed of each gear in the transmission. Which is what you want when towing, and is why tow packages typically come with lower axle gears. Its not just to run more RPM at a given speed, its to increase the ramp speed of each gear.
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dodgerammit
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Re: Torque Converter Recommendation

Post by dodgerammit »

Stuka wrote: Thu Apr 09, 2020 1:54 pm
rocklaurence wrote: Thu Apr 09, 2020 4:36 am IMO, with the low axle ration I'd go with a TCI Saturday Night Special. It has a stall around 2000 RPM and will allow your motor to reach its torque range better off the line. If you do any towing, you'd likely want to add a Aux trans' cooler. Im going to put one in my shop truck to improve performance while towing. With the tires and gears I have now, it will hit stall around 40 mph around town which is perfect.
The problem with a higher stall is he will run more RPM on the HWY, and will put more load on the cooling system. The cam he has selected really does not require a higher stall than stock.

It would pick up off the line acceleration by letting it hit a higher RPM before it grabs. But, it will not impact the ramp speed of each gear in the transmission. Which is what you want when towing, and is why tow packages typically come with lower axle gears. Its not just to run more RPM at a given speed, its to increase the ramp speed of each gear.
Yep. Mine from Hughes is 1200rpm stall. Pretty close to stock.
84 Grand Waggy-Radio Flyer (Garnet Red/3M Ebony Metallic woodgrain, with honey interior) AMC 360 :cry: 2004 4.8LS/Advance Adapter/727/242 D44/AMC20 Serehill tailgate and headlight harnesses :fsj: Ongoing thread-viewtopic.php?t=11897

92 Wrangler Islander 4.0/32RH/231 D30/D35 RHD
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