Conversion of the Avanti Powershift AT to 1st Gear Start in Drive- Stan Gundry I'm describing how I created a 1st gear start in Drive on my Avanti Powershift automatic transmission (AT). I assume you all realize that the Powershift actually starts out in 2nd gear when it is in Drive. First I must give a disclaimer. John Metzker created this modification, not I. In fact, 11 years ago he walked me step by step through the conversion I will describe below. He is the Studebaker expert who answers AT questions in the Co-Operator column in TURNING WHEELS. His knowledge of even the details of ATs is amazing, and every time I speak with him I come away awestruck by his knowledge. I spoke with John just two days ago to clarify a thing or two. First, there are two ways that one can achieve the same result. According to John, each approach has its own advantages and disadvantages, but either one works well. John says he decides which route to take based on which donor AT is more readily available in the local salvage yards at the time. Keith Brooks has mentioned on this list several times that 1st gear start in Drive can also be achieved with an FMX transmission from the late 60s or early 70s. The FMX was the Ford version of the Borg-Warner transmission and was built by Ford, not by Borg-Warner. When Keith has mentioned this, I have questioned whether or not that was really so. But in our phone conversation, John confirmed that Keith is quite right that the 1st gear start can be achieved with the FMX. In an email written to this list 2 , years ago, Keith described the conversion as basically taking the FMX valve body, the FMX case and guts, but using the Powershift input and output shafts. This also requires running a vacuum line to the vacuum shift modulator. John agreed that this is basically how it is done with the FMX, though it works better if a TransGo shift kit is also used. Use of this kit has something to do with a weakness in the FMX setup, I believe the valve body. Perhaps Keith can clarify that point. If you want more info and detail on the FMX route, ask Keith. But it appears to be very similar to the next option. It is possible the FMX AT will be easier to find than the other choice, an AMX AT. The approach I took, under John's tutelage, was to start with a Borg-Warner AMX AT. These were used behind AMC V-8s from 1967-71 (either the M-11 or the M-12) and represent the next generation of iron case Borg-Warners after the Powershift. You install the Powershift coarse spline input shaft and front pump in the AMX unit, you install the Powershift manual lever in the AMX unit but you do not install the throttle pressure lever that originally went through the center of the manual lever. Instead you plug the hollow center of the manual lever shaft with an expansion plug and sealant. (Warning: DO NOT use the Powershift piston in the front clutch; you must use the AMX piston. I mention this because the Studebaker and AMC parts have the same casting number and superficially look identical, but they are not. The AMX version has a check ball in it.). Now if you want to use the AMX output shaft and tailpiece you are done. But it will not look even close to stock. And you will need to have a drive shaft custom made because AMX output shafts have different lengths that the Powershift. I did not want either of these, so here is what is required to get around that problem after you toss aside the AMX output shaft, spacer at the rear of the AT, tailpiece, and associated parts. You need to install the rear pump (but without the drive key and gears), governor, speedometer gear with drive ball, and output shaft and thrust washer from a Powershift. You also need the oil collector tubes from the Powershift. But before doing any of this, drill out the holes for the oil collector tubes in the AMX case to 5/16" so they will accept the Powershift oil collector tubes. The rear pump, which no longer has its guts, is now just a spacer and a support for the Powershift output shaft (the AMX does not use a rear pump). Somehow you need to get lubrication to the bushing in that Powershift rear-pump-turned-support. Do this by drilling and tapping a hole into the lubrication circuit of the AMX valve body to accept a 90 degree brass elbow with compression ring fitting. This fitting in turn accepts a cut-down Studebaker tube (part number 1541251) routed to take lubrication to the output shaft bushing in the now-empty Powershift rear pump housing. There is no way to better describe thisonly a picture can adequately depict it. See the photo that I will place on my website Photos page in a week or so. After all of this is installed, attach the Powershift tailpiece or extension housing. This leaves one last little detail. Screwing in a new vacuum shift modulator on the lower left side of the AMX case. Ooops, you can't do that because the Powershift tailpiece is in the way! But you can solve this by some very careful and precise grinding of the tailpiece case with a Dremel tool and its cutting/grinding disks. (See another picture to be posted on the Photos page of my website showing what has to be ground away). When enough is ground off the case to achieve clearance for the modulator, install the vacuum modulator. But remember that there is a rod that is inserted first that goes from the modulator to the valve body; if that is missing or bent, make your own from a 1/8" steel rod with rounded, polished ends. The finished length should be either 3.444" or 2.944", depending on whether you are using the longer (early) or shorter (later) modulator. Now, run steel tubing from a vacuum source on the intake manifold down to the modulator, and use rubber tubing to bridge from the modulator to the end of the steel tubing. Use the Powershift pan and dipstick and dipstick tube. The AMX has an electrical provision for kick down through the throttle. So if you want that rather than a manual downshift, you will need to install a kick down switch on the throttle control bellcrank assembly, connect it properly to a power source, and run a wire to the electrical spade terminal on the right side of the AMX case. The only two obvious things that will not look stock about this set up will be the vacuum modulator and tubing and the kick down switch and wiring. Of course, if you are going to go to all the trouble of making this conversion to achieve a 1st gear start in Drive, you should also rebuild the unit using all the appropriate standard items in a rebuild kit and checking critical parts for wear. Rebuilding a Borg-Warner is not rocket science, but that is another article. In fact, that article has essentially already been written and published in TURNING WHEELS, July 1985, pp. 25-27, "What the Shop Manual Won't Tell You About Rebuilding a Borg-Warner Model 8 Automatic Transmission," by Stan Gundry with John Metzker. The same principles outlined in this article will apply to rebuilding this unit, as it is the same essential AT. Before stopping, I should also mention that some of the Powershift parts mentioned above that go into the AMX AT can also be taken from most of the 60s Studebaker (Borg-Warner) Flightomaticsparts such as the front input shaft and pump and the tailpiece. But always check the Studebaker Parts Catalogs before doing this to make sure the Flightomatic and Powershift actually do share the same part #. For instance, the output shafts from the two look the same but are actually significantly different. The Powershift output shaft is the one to use; the one from a Flightomatic can be made to work, but only after some significant precision machine work. Now remember, in a week or so this article will appear on the Updates and Questions page, and the two photos will appear on the Photos page of my website, www.avantipublishing.com. And if any of you get really serious about doing the AMX conversion, feel free to call or email me with your questions. There are also several other tips I should give you about rebuilding the unit. I do not want to put my phone number on the web, but it is in the AOAI Roster or I can email it to you privately. BTW, I have been driving this conversion for 11 years and love it, and have had no trouble. Stan Gundry, Author/Publisher What The Shop Manual Won't Tell You: Studebaker Avanti Restoration and Maintenance. For information about this book, go to: www.AvantiPublishing.com If you have questions, write me at: sgundry@aol.com (Taken from the AOAI Chat Group - Mar 2003)