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Discussion Starter #41
Where did you get that built at? we would love to know all the information you can get on it.

lockup built into the 700r4??? can you explain how that works? (I'm an auto newbie)
 

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why 800 for stall? just curious, i thought most diesels were around 1200 or so. maybe that's not even right? my low stall converter on my 700r4 is 1200-1400 i think.
 

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I said about 1200'ish when spec'ing it- he said 800 would be better, especially for a diesel & the RPM range I'm running. Cant really change it now :). This guy builds custom racing converters and has been in business over 30 years, I trust em ;)
 

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awesome, i'd really like to see how it turns out. i will be getting a well built transmission one of these days and i want to get a custom converter built for it.
 

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mine is also set up this way i mean the lock-up style...
the guy who built the trans said it was a cable lock-up?
mine works nicely...
still shifting perfectly after 2800 miles...
not many miles but no problems...
later
 

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I understand you can make the stock 700r4 lockup without a computer by way of pressure switches in the valve body which then engage the stock TCC solenoid.

I'll hunt the info down and post what I find.
 

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Question...

All of those who are using a 700r4 or th400 behind their 4bt, you must be using the GM adapter, right? So did you mount your motor in there with the 10 degree passenger side tilt to keep the tranny level? Thanks, Jed
 

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The TV cable on these has to have the correct geometry! Impropper TV cable setup will kill the 700R4 in a hurry. One of the auto magazines had a good setup photo some time back. I will look for the page. It will not work to just get close to the setup. There is also a company online that makes a setup for attachment on Quadrajet carbs. It may be adaptable. Search for it there is good info on that site
Lockup can be done in the transmission with switches. There is no computer needed. The overdrive automatically locks up after the tranny is in 4th and pressure comes up. Any tranny shop can do this, it's common with rodders. The lockup is then switched off when the brake light comes on, at least that is how my street rod works. My street rod also has a vacuum switch. If the vacuum drops the lockup unlocks. That part won't work with boost. There could be a switch added to the accelerator or on the injector pump that unlocks the lockup with full or near full throttle application.
Use care with bolt selection bolting the converter to the flywheel. The bolts cannot hit the converter shell. The lockup clutch is right behind the shell where bolts would hit. If the bolts bottom on the converter the clutch band is broken inside the converter. This will lead to a 200 to 400 mile transmission destruction. I know I did it twice before figuring out what the problem was. Both times I had to have a trailer come to retrieve my street rod, it was DOA.
 

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The TV cable on these has to have the correct geometry! Impropper TV cable setup will kill the 700R4 in a hurry. One of the auto magazines had a good setup photo some time back. I will look for the page. It will not work to just get close to the setup. There is also a company online that makes a setup for attachment on Quadrajet carbs. It may be adaptable. Search for it there is good info on that site
Lockup can be done in the transmission with switches. There is no computer needed. The overdrive automatically locks up after the tranny is in 4th and pressure comes up. Any tranny shop can do this, it's common with rodders. The lockup is then switched off when the brake light comes on, at least that is how my street rod works. My street rod also has a vacuum switch. If the vacuum drops the lockup unlocks. That part won't work with boost. There could be a switch added to the accelerator or on the injector pump that unlocks the lockup with full or near full throttle application.
Use care with bolt selection bolting the converter to the flywheel. The bolts cannot hit the converter shell. The lockup clutch is right behind the shell where bolts would hit. If the bolts bottom on the converter the clutch band is broken inside the converter. This will lead to a 200 to 400 mile transmission destruction. I know I did it twice before figuring out what the problem was. Both times I had to have a trailer come to retrieve my street rod, it was DOA.

the same people, bowtie overdrives have the adapters, etc. Yes, care needs to be taken, that's why i'm going to try it with a not so great trans first. www.transmissioncenter.com has a good writeup on TV cable adjustment. Honestly, i'm not sure how easy it will be to setup the 700r4's throttle to be adjusted properly... I haven't made my brakets yet, but they aren't the easiest thing to come up with at least for me...
 

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yeah mine has the tilt i used the advanced adapters setup to the 300 t case....
and by the way 3800 miles still going fine no color change in the trans fluid....

later all
 

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Discussion Starter #55
Thanks for taking the bullet for the rest of us JBox. Keep us updated on what that tranny is doing for you, please.
 

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• Does anyone else (besides JBox) have pictures of how they tackled the TV cable bracket/mount?
• Also does anyone have a picture how the motor looks installed 10 degrees off?
• How are the shift points for WOT? My understanding of the 700r4 is, there are springs controlling WOT shift points and to the best of my knowledge those are only available in a diesel application for 3600 RPM and the 4BT redline is 2500 (?). So I would think the trans wouldn’t up-shift at WOT because it isn’t getting the RPMs. Obviously just don’t do WOT and the trans will shift right, but does anyone know anything about WOT up-shifts?

Side note my 700r4 behind my 6.2 has been putting up with more than 400ft/lbs quite well. My 700r4 was built to handle 650 hp and 650 torque.
 

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Discussion Starter #58
Jbox,

This was a used tranny if I'm not mistaken, yes?

Very good news, heck if you can get 50K out of a used 700r4 with propper mods you are way ahead financially opposed to the guy whos only going to drive his swap 100K. and spends thousands on a NV4500 or 480Le.
 

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there are other advantages to the 4L80E other than reliability. I personally don't doubt the potential of a 700r4 in a DD vehicle. I do however doubt it in a DD/tow rig. I plan to tow 7k lbs regularly. I don't want to have to worry about my trans, and I want to be able to tow in OD and not worry about that either. the .75 OD in the 4L80E while it could be lower for DD use, is good for towing.

Also, i can control the shift points/firmness/etc/etc with the 4L80E from inside the cab :D the compushift controller, while expensive has a lot of very nice features that you will never see with a 700r4.

In related news...my unknown condition, supposedly rebuilt, 1983 style 27spline input 700r4 has put up with 3-400 miles so far. if i could get it to stop leaking fluid, i'd put a lot more miles on it... it seems to shift pretty well, though my lockup is funky. I have the kit from bowtie. when i hit the brake to go into a turn it unlocks the converter like it's supposed to. however, when i let off the brake, it locks up immediately. Then when trying to accelerate out of the turn, it stays locked and in OD, this bogs the engine and blows a large plume of black smoke. I have started shifting out of OD into D when driving in turns... maybe there is a solution to this, i haven't found one yet though...
 

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Discussion Starter #60
Good info DieselDurango... I think I'm gonna go the route you have gone with a totally used 700r4... just run the snot out of it... heck even plow my driveway with it and see what happens... I already have it around. I'll be putting it in a 94 s10 blazer with SFA swap.
 
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