I’ve been working pretty steadily on my 1939 Ford Deluxe Coupe build. I’m currently having a problem trying to install a turbo 350 trans onto a 327 block which has a 283 crank. I was test fitting the torque converter into the pinion? ( not sure if I’m using the right terminology here) I mean the hole in the back of the crankshaft, the converter slips in the crankshaft fine but it bottoms out in the hole before the converter can meet the flexplate. My guess is that portion of the converter is about 1/16” or so too long or the 283 crank hole is too shallow. It would seem to me that I need a different torque converter. Has anyone experienced this problem? I’ve attached some pics. Thanks for any suggestions! Doug
If the converter isn't bottoming in the front of the transmission when it's installed, washers at the converter to flexplate lugs will cure the problem. You just don't want the converter to be in a bind when installed in the trans and bolted up to the engine.
Ok thanks I’ll remove those lock washers, thank you. I just picked up this other torque converter this morning from one of my gear head buddies. The front portion that goes into pilot hole is visibly shorter and it fit perfectly into the 283 crank. We confirmed that the input side of the converter will fit into turbo 350 trans with no issues so I’m gonna give this a try.
There's no pilot bushing in that crankshaft. The converter he started with looks like a stock Dacco B1A.
I thought I had brought you guys up-to-date on the latest issue. I’m having with the torque converter but apparently I did not. The torque converter with the smaller pilot fit perfectly into the back of the crankshaft, howwever, that converter was for a powerglide transmission not a turbo 350. So basically nothing has changed and I’m back to square one with no progress other than knowing the following facts: It’s not bottoming out because of a pilot bushing there’s no pilot bushing in the crank. It’s not bottoming out because the flex plate is installed improperly it’s installed correctly. It’s not bottoming out because it’s hitting the bolts on the flex plate. Plain and simple it’s bottoming out because the 1.7” pilot hole in the 283 crank is too shallow. What I think I need is a torque converter for the 350 turbo but with a shorter pilot like the one used on a power glide trans. I’ve called a couple transmission shops but nobody seems to understand this problem I’m having and google searches have also proved unsuccessful. I can’t believe nobody else has found this to be an issue.
When you bolt the trans up and the converter pushed all the way into the trans what is the gap between converter and flexplate ?
Knowing that the TC is not sitting properly in the crank I have not attempted to install the transmission. When I test fit the TC into the crank I’m approximately 1/8” away from the flex plate. I can’t put a spacer behind the flex plate either because I took some very careful measurements and I only have .100” to work with, meaning the “play” I need for the TC to operate properly.
Something is up with that converter obviously. If the glide converter fit any 350/400 converter should also fit. At least, as far as I know. Sound like another jacked up Daaco converter story to me. I got three out of a box one time, all three had only been welded half way around the neck. They were 25 bucks back in the day and would cost you hundreds in comebacks when they came apart. You shouldn’t have a problem rounding up another turbo 350 converter. Even just a junk one to mock up.
you don’t want to space it there anyway. As I’m sure you have figured out by now the converter should sit all the way in the crank and flush against the fly wheel. Then you should push it back an 1/8 to 3/16 of an inch and put your bolts in. If it’s not all the way in the crank, it will wipe the pump out, no matter what you do with the fly wheel spacing.
Yes I’m in total agreement with that. Please see attached photo of the pilot hole in the crank. Does this look normal? There is a little bit of a ridge at the rear of the pilot hole. Not sure if this is my problem. Should I take a burr to it? The pilot hole itself measures out to 1.7” which is correct.
Maybe someone with a 350 converter laying on a bench can take some measurements for you to compare to the one you have.
""""GM Automatic Transmissions """" If 1/8 gap between Flex plate & mount ears of converter, Converter nose up against centering of crank, """ Install """a 1/16 spacer washer , You want a Air gap in between Flex & converter ear mount .... Its No big deal , we somtimes have to install Spacers on 10-15 k setups 1/4 - 1/2 spacers ,,, Its Critical /Important to have converter nose against crank centering pilot hole before touching Ears to Flex plate ,, Also if you donot know ,when tightening Converter bolts, You snug each bolt three or four times, rotation engine flywheel before final torque
I don't know what part stores are next to you but where I'm at. I can go to advanced auto parts and get a torque converter for a 70 Chevy Chevelle with a Turbo 350 the next day for about 80 bucks.
Rarely are the pilots on converters replaced during a rebuild. They are non wear item. The pilot on the torque converter pictured, looks like a normal factory pilot. Dacco converters do leave a lot to be desired, but I don't think its a "them issue". The mounting pads also look to be normal height. I have a 350 crank on the shelf, a 327 and a 489 BBC on engine stands at the shop. I could measure the crank registers on all 3, next Monday when back to the shop. I don't think I have any stock 12" GM converters to measure at this time and a stock 13" converter has a different style pilot, so comparing the two, may come up different. This may sound like a crazy scenario, but I have run into similar situations like yours with 2 early to mid 60s Chevy small blocks and 1 Buick 455 that all had manual transmissions installed, that were originally automatics and the bores for the pilot bushing were only rough machined, not fully machined from the factory, only the bore for the torque converter pilot was machined to the correct size. Had to machine the pilot bushing to fit the crank, which was a real PIA. Rumor goes, some GM cranks were only machined for automatics. Don't know how much truth there is in that rumor, but I have seen it with my own eyes 3 times in 40 years. Could it be possible that your crank was only finish machined for a manual trans with a pilot bushing, I don't know? For your sake, hope not. Let me know if you want to measure. Bill
Wondering if a the back of the converter hub is solid material and a machine shop could cut off the required amount in a lathe....
Or if solid carefully grind off the amount needed. I had an AMC V8 engine that came with a stick transmission, and the crank hole was a different size than the same year engine that came with an automatic.
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