Anyone Using a 700R4 or 200-4R?

[Bilster]

Anyone Using a 700R4 or 200-4R? Can you give me details on what you used...Hughes adapter spacer....which flexplate? I heard a Hughes adapter with a stock 5.3 flexplate but I haven't been able to get a firm answer.

[retrolsx]

The LS engine is capable of running any older style GM transmission with ease. As mention at the beginning of this chapter the bell housing bolt pattern is almost identical to the Gen 1 small block. The use of the older transmission only requires only a few off the self items depending on the transmission used. This is becoming a very popular method to drop a LS engine in because of the minimal amount of modifications that have to be made to the car. The older transmissions need no modern electronic or adapters for speedometer cables and can make a quick conversion with existing equipment. The stock driveshaft can even be used in several applications.

Older GM Automatic Transmissions.
All the traditional GM the Powerglide, TH-350, TH-400, 700R4 and 200R4 use all the existing mounting locations on all Gen III and Gen IV LS and will bolt directly to the block. The next step is to properly align the flywheel to the torque converter. This can be accomplished in one of three ways.

The first and most cost effective solution is a GM spacer and longer bolts that will space out the OEM flywheel to properly align it with the older style torque converter. The slots that the torque converter bolt to can also need to be elongated for proper alignment.

The OEM flywheel can be seen with the dished center. This curve is what needs to be spaced out in order to attach the torque converter. The older Gen 1 small blocks featured a flat style flywheel.

The only version of the LS engine that does not require the adapter spacer for older transmission is the 6.0L Vortec truck engine when coupled behind a 4L80 from the factory.

The second option is to purchase a replacement flywheel that will appropriately space out the flywheel without the need for a spacer. The most common used version is the TCI flywheel that is also SFI certified for vehicles that plan to spend time on the track.


The third option is a custom torque converter that eliminates the need for an adapter kit. This is available from Bowtie Overdrives and will simply bolt to the OEM flywheel and slide right into the older GM transmission. This is a great option for those who want a higher stall and plan to run the older GM transmissions.

When running the 700R4 or 200R4 there are additional steps to make the system properly engage the transmission. These style transmissions relay on the throttle valve (TV) to properly engage the clutches. If the (TV) system is not properly synchronized its will not properly engage the clutches and cause a catastrophic failure of the transmission. This system can be adapted to run off the LS engines in one of two ways.

The first option is from Bowtie Overdrives that operates the (TV) cable as intended with a bracket kit for cable operated throttle bodies. This system will also need a longer spring added to the transmission. Without the longer spring the transmission will experience a Short Spring Syndrome condition which can quickly prove fatal to the transmissions frictions.

The second options is a constant pressure valve body from TCI. This removed the possibility of a catastrophic failure by forcing the transmission to operate at full pressure at all times. Once installed this will reduce the TV cable to nothing more than a shift detent cable only.

[the gas man]

OK, first off. LS2 is going into my c4 vette. Im reusing my worked 700r4. Now when you say oem flexplate, your not talking about the sbc flex but the ls2 flexplate that needs to be spaced and just reuse my 700's converter. Also this is the first I've heard about the constant pressure valve. With this constant pressure, there is no harm to the tranny??
Thanks Ernie

Also are you all working on c4 long tube headers

[chuckd71]

nevermind .