Its pretty much unanimous here....check out edge racing or circle d. If you want a gutted out upgraded/reinforced stock converter that will offer pretty good performance you can't go wrong with either (around $500). If you want a true custom made converter for the best performance go with circle d, they start I believe at $750 and go up to $1050. I went with the 258mm Pro II 2800-3000stall ($850), It should be ready by the end of next week.

 

Just don't expect your fuel economy to go UP if you install a higher-stall-speed converter.

 

Just don't expect your fuel ecoomy to go UP if you install a higher-stall-speed converter.

From searching this forum and others forums, pretty much everything goes up including mileage.

 

trans can you explain why mpg wouldn't stay the same or go up? i really know nothing about this. tks

 

Because a higher-stall converter will generally have more slip (in the converter) when the TCC is unlocked. More slip = less efficiency = lower fuel economy.

Think of it this way.... when you take off from a stop (gently), watch the engine RPM. As soon as you tip into the throttle, the engine speed will come up to some value (let's say 2000 RPM) before the truck starts moving. Now let's say you install a high-stall converter. Now your RPM may come up to 2400 instead of 2000. Your engine burns more fuel at 2400 RPM than at 2000 RPM.

If Chrysler could change the converter blading (use a higher-stall converter) to give better performance AND better fuel economy, don't you think we would have done that already?

 

You should have 4.56 gears for a tire that tall and heavy.

I'm planning 4.56's for my 32" Grappler's
they weigh about 90 pounds on my stock 20's

a 37" Trail Grappler is almost 100 pounds without a Rim,
and your effective gear ratio is dropped from 3.92 to about 3.48:1

Combine that with a higher stall TC is going to raise your transmission fluid temps considerably.
You'll likely need a deeper tranny pan, and maybe an upgraded cooler.

 

Hey Blackramhemi,
I was just recently told if I run 37s that I only need to gear up to 4.11s because if I get anything bigger then 4.11s then my top speed would only be like 60mph. I'm not sure if that's exactly true but I've heard it from 4 people at a transmission shop near where I live.

 

Is there anyone running a 258mm single disc tc in there 4x4, maybe with a lift that we could get some feed back from

 

I don't know if you read this but its a 258mm triple disc circle d install thread

http://www.**************/forums/showthread.php?p=4325082

 

Yeah when I meet with Chris last week he gave me the tour and he showed me the $500 one vs the custom 258mm single disk ($850 one). There really wasn't any comparison because it was a far superior converter inside and out. I believe the single disk would be the best choice because Chris told me unless you tow 5-6k consistently I won't be getting anything out of a multi disk. He also told me the 258mm single disk would be able to handle 900-1000hp and my tranny would go out before I could achieve this. He's installed these in plenty on lightings and chevys with twin turbos pushing well over 700hp and they never had an issue. I pretty much left know I was getting excellent custom torque coverter and can't wait to take that stock POS out.

 

When are you getting yours man? You have a shop to take it to yet, for the install?

 

It will be ready on Wed or Thursday but won't be picking it up until Friday. Yeah I have two options either Juan or Flaco both are Houston Performance Truck Sponsers. I would say Juan because all he doesn't is transmission work and is gonna charge me $225 but Flaco actually owns a 2011 rt and is more a performance shop, he charging me $300. Both prices are install with all fluids....you know of any other options?

Did you do your header install yourself or did AL do it?

 

x2

a Higher Stall TC in an undergeared truck rolling larger tires is also going to have trouble staying in lockup (1:1)

So expect a significant drop in fuel economy, even at highway speeds
and higher trans temperatures with a TC that's always slipping.

 

OK, just got home from having the TC put in. What they said would take 4 hours and $380, turned in to 8 hours $400. It looks as if I may need to get the bigger tranny pan as the whole way home, I was at lowest 175, but got as high as 200 on temps in stop and go traffic. So I held off stomping it. I may let it cool and then go try it just to see if I will see the results off the line. Even with my Jet 180 T-stat, I am still in the 190-200 temps on the coolant. Maybe I actually needed to disconnect the Negative battery cable?! Any thoughts or input on all of this?

Like I said, higher stall speed = less efficient. And all your inefficiencies get turned into heat. So less efficient converter = more heat generated = higher sump temp = shorter trans life.

 

Like I said, higher stall speed = less efficient. And all your inefficiencies get turned into heat. So less efficient converter = more heat generated = higher sump temp = shorter trans life.

Well I've had a Circle D TC installed for about 3 weeks now and haven't experienced anything you've mentioned. I haven't lost any efficiency, heat on my tranny is the same, and lastly its a hell of alot more fun to drive now!

I know your some kind of Engineer and all but what sounds good in theory doesn't always translate to the real world. For example, I work at a refinery and deal with Engineers all the time. They try to change how something works but end of making it worse. It all could have been prevented if they talked to operators and got their opinon first because they work with the equipment everyday....just saying

It's kind of what we have here with guys and their experience with different mods on their trucks. IMO I've much rather listen to a guy that hands on experience than someone that doesn't.:smileup:

An experience person will always win out vs someone that read it in a book somewhere:doh:

 

sorry double post