The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - What automatic overdrive are you running behind your Gen 1 small block?

Kawabuggy · 07-04-2018, 10:10 AM

Guys, please note that both the 700R4/4L60, and the TH200-4R are some of the MOST difficult transmissions to swap into vehicles that were not originally equipped with them. Both of those transmissions require a TV-throttle valve-cable to run properly. That cable, if not installed, and adjusted, correctly will burn your brand new transmission to the ground in under 50 miles. Further, it's not just how the cable is adjusted, the geometry of setting up the cable at the carburetor, or throttle body has to be spot on or total transmission failure will be in your near future. Do some research on this subject BEFORE you jump off into installing one of these transmissions into anything. Here's a guy posting about what is needed to set the TV cable up correctly; http://purplesagetradingpost.com/sum...o/700R4p1.html

Please note that if you are off on the adjustment, or geometry, the trans is going to melt down requiring repeated rebuilds until you get the adjustment and geometry correct.

The 2004R in stock form is also NOTHING to write home about. Either unit can be built to handle a little power, but by the time you waste thousands of dollars building one of them up you realize that you could have bought a used 4L80E for half the price, and have a transmission that is twice as strong as your 700/2004r could ever dream of being. Even after spending $2500-$4000 building up a 700, it will still be weaker than an all stock 4L80E. 4L80E's can be set up to run without a computer. There are many ways to do it. Or, if your engine produces 300 HP, or less, and you don't plan on running tires larger than 31", and you never plan on towing ANYTHING that weighs more than 2000 lbs., then a 700 might work for you. Might... As you can tell, I'm not a 700 supporter. I've been building transmissions for a living since the early 90's. With all of the other transmissions available to swap in and accomplish your desire to have O/D, and a lower 1st gear ratio, the 700 is the last transmission on the face of the earth that I would be looking at. It was absolute JUNK and even GM dropped it like the turd it was after a short run of only 10 years. Most other good transmissions that GM built ran for significantly longer than that. The 4L80E was built from 1992 through 2007, and was still being installed in GM vehicles long after 2007 until the old inventory finally ran out. Trucks need a truck transmission-in my opinion. Don't put a junk car unit (700r4) into your truck. Find a used 4L80E, and switch it over to run without a computer and you will be super happy. Or, install a stand alone controller-TCI EZ TCU, and have the ability to change shift patterns, and/or timing, and or pressure, at the punch of a few buttons.

There are now stand alone controllers on the market that will allow the installation of the 6L80E's and 6L90E's.. Yeah baby!

07-04-2018, 10:10 AM	#5
Kawabuggy Registered User Join Date: Jul 2018 Location: Houston, TX Posts: 16	Re: What automatic overdrive are you running behind your Gen 1 small block? Guys, please note that both the 700R4/4L60, and the TH200-4R are some of the MOST difficult transmissions to swap into vehicles that were not originally equipped with them. Both of those transmissions require a TV-throttle valve-cable to run properly. That cable, if not installed, and adjusted, correctly will burn your brand new transmission to the ground in under 50 miles. Further, it's not just how the cable is adjusted, the geometry of setting up the cable at the carburetor, or throttle body has to be spot on or total transmission failure will be in your near future. Do some research on this subject BEFORE you jump off into installing one of these transmissions into anything. Here's a guy posting about what is needed to set the TV cable up correctly; http://purplesagetradingpost.com/sum...o/700R4p1.html Please note that if you are off on the adjustment, or geometry, the trans is going to melt down requiring repeated rebuilds until you get the adjustment and geometry correct. The 2004R in stock form is also NOTHING to write home about. Either unit can be built to handle a little power, but by the time you waste thousands of dollars building one of them up you realize that you could have bought a used 4L80E for half the price, and have a transmission that is twice as strong as your 700/2004r could ever dream of being. Even after spending $2500-$4000 building up a 700, it will still be weaker than an all stock 4L80E. 4L80E's can be set up to run without a computer. There are many ways to do it. Or, if your engine produces 300 HP, or less, and you don't plan on running tires larger than 31", and you never plan on towing ANYTHING that weighs more than 2000 lbs., then a 700 might work for you. Might... As you can tell, I'm not a 700 supporter. I've been building transmissions for a living since the early 90's. With all of the other transmissions available to swap in and accomplish your desire to have O/D, and a lower 1st gear ratio, the 700 is the last transmission on the face of the earth that I would be looking at. It was absolute JUNK and even GM dropped it like the turd it was after a short run of only 10 years. Most other good transmissions that GM built ran for significantly longer than that. The 4L80E was built from 1992 through 2007, and was still being installed in GM vehicles long after 2007 until the old inventory finally ran out. Trucks need a truck transmission-in my opinion. Don't put a junk car unit (700r4) into your truck. Find a used 4L80E, and switch it over to run without a computer and you will be super happy. Or, install a stand alone controller-TCI EZ TCU, and have the ability to change shift patterns, and/or timing, and or pressure, at the punch of a few buttons. There are now stand alone controllers on the market that will allow the installation of the 6L80E's and 6L90E's.. Yeah baby!