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Converter/flex won't line up 66/67

Moparnocar

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Putting a 67 383 727 trans behind a 1967 413.

I know 66/67 slines on the converter are different, but what about touque converter bolt holes location? It's off by almost 1/4 . I've spun the converter twice t
 
Mark each converter bolt hole 1,2,3 and 4. Mark only one hole on flexplate. Put bolt in marked flexplate hole and number 1 convertor hole. Turn engine to see if all hole line up. If not put marked flexplate hole in convertor hole 2, turn motor to see if holes line up. Follow this process with 3 and 4 holes. If you do all 4 holes and they still don't line up you have a problem.
 
Mark each converter bolt hole 1,2,3 and 4. Mark only one hole on flexplate. Put bolt in marked flexplate hole and number 1 convertor hole. Turn engine to see if all hole line up. If not put marked flexplate hole in convertor hole 2, turn motor to see if holes line up. Follow this process with 3 and 4 holes. If you do all 4 holes and still doesn't line up you have a problem.

This is what I did, still won't line up. Flexplate holes seem alot smaller than I remember
 
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then you have a flexplate/ converter mismatch
did you check the flexplate to converter alignment before you bolted the trans to the engine?
 
then you have a flexplate/ converter mismatch
did you check the flexplate to converter alignment before you bolted the trans to the engine?
I did not, probably should have..

That's why I'm wondering if there is a difference between that pattern on 66/67 big blocks. I was under the assumption they were the same
 
I did not, probably should have..

That's why I'm wondering if there is a difference between that pattern on 66/67 big blocks. I was under the assumption they were the same
are you able to start and thread a converter bolt at all?
don't quote me , but it seems I remember 2 sizes of bolts that were used depending on application. maybe the flex plate holes are actually smaller and not a different spread pattern. I'm not sure.
a flexplate for a 10 or a 9" converter will be noticably smaller , by about 1/2".
 
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4BF2A1AF-5F42-4FEC-89BE-797CFCC170E1.png
There is a 11” pattern and a 11 3/4” pattern..
The larger bolts were only stock on the Hemi, but some aftermarket converters used them too...
 
A 1967 413? The 413 engines were last produced for passenger cars in 1965. Do you have a truck/industrial engine? Could that be part of the problem?
 
A 1967 413? The 413 engines were last produced for passenger cars in 1965. Do you have a truck/industrial engine? Could that be part of the problem?
It came out of a low mileage 1967 imperial, it was original. The owner said it was a 440. It had 915 heads, 1967 440 intake/carb etc. It was unmolested. The pad was stamped (4 1) almost like a mis stamp, and they ran out of 440 short blocks that day, and thought no one would notice. No one did till I tore it down and measured the bore. Car was turned into derby car, I got the engine full dressed
 
Please don't take this as an insult, but because it has happened..... do you maybe have the flexplate on backwards? If so, the offsets will be backwards, and wont line up anywhere.
 
Please don't take this as an insult, but because it has happened..... do you maybe have the flexplate on backwards? If so, the offsets will be backwards, and wont line up anywhere.
No insult taken, open to ideas

No, not backwards, unless Chrysler did In 67, I never removed it
 
My experience was that the flex plate holes were quite a bit larger than standard 5/16" torque converter bolts. I tried 3 or 4 flex plates including an old Chrysler one before settling on one to use - holes were oversize in all of them. Seems that maybe Hemi's use 3/8" bolts and special flex plate. If you didn't mark the off-center flex plate hole and torque converter hole before assembly, it may make quite a chore getting them to align once all up in the chassis. I turned the crank to put the off-center hole in the flex plate at the bottom and marked it with a sharpie. The converter off-center hole had been marked with a sharpie and I just rotated the converter until the two marks lined up and started the first bolt. Then I rotated the crank to each of the other 3 and inserted them, and then went back around and torqued them. If the off-center flex plate hole is marked you have about 4 possible combinations and with neither marked I think you have about 16 possible combinations and 15 of them will be wrong.

IMG_3940_zps7kugou8p.jpg
 
My experience was that the flex plate holes were quite a bit larger than standard 5/16" torque converter bolts. I tried 3 or 4 flex plates including an old Chrysler one before settling on one to use - holes were oversize in all of them. Seems that maybe Hemi's use 3/8" bolts and special flex plate. If you didn't mark the off-center flex plate hole and torque converter hole before assembly, it may make quite a chore getting them to align once all up in the chassis. I turned the crank to put the off-center hole in the flex plate at the bottom and marked it with a sharpie. The converter off-center hole had been marked with a sharpie and I just rotated the converter until the two marks lined up and started the first bolt. Then I rotated the crank to each of the other 3 and inserted them, and then went back around and torqued them. If the off-center flex plate hole is marked you have about 4 possible combinations and with neither marked I think you have about 16 possible combinations and 15 of them will be wrong.

View attachment 838732
They seem small on mine, off by about 1/8 to the side

How is there 15/16 possibilities? There's only 4 as far as I can see

May end up hogging out the holes
 
Mathematically there would be 16 possible..... but not if they are in a fixed position. Four possible, three of them wrong.
If you have tried all four, then either the flexplate or converter is wrong. Since you say the flexplate wasn't off the engine, which means it's likely not aftermarket, and worked fine in the imperial, the likelyhood is the converter is wrong. The factory flexplate offset hole is easy to see, the hole is NOT centered on the tab, the converter, not so much. On mine, i just get a can of spray paint and mark both with a big splotch of paint.
Rather than pull it apart again, i would just oval the hole in the flexplate .
Edit: also if memory serves, stock converter bolts are 5/16, hemi and most aftermarket or race converters are 7/16.
 
If you have the off-center bolt on either the flex plate or the torque converter marked - then there are 4 possibilities. But if neither is marked and all you can see through the opening is one flex plate and one torque converter hole each at a time - you can rotate the converter through all 4 positions on the first flex plate bolt and never know if you find a match because you can't see all the holes at once. You can then rotate the flex plate to bring the next hole into view and again rotate the converter through all four positions trying to find a match for one where all the other holes line up - but you really never know because you can't see all four holes in each at once. 4 x 4 = 16 possibilities but it's actually worse than that because unless you get real lucky you may not know when you hit the right alignment because you can't see all the bolt holes and their alignment at one time. It's enough to drive you crazy.

Short of pulling the transmission again here is what I would do, rotate and mark the 4 torque converter holes 1, 2, 3 and 4. Carefully measure center to center for each set of holes and record the dimensions until you identify the off-center hole. You aren't dealing with a major difference - 1/4 inch or less I think, so have to measure carefully. Turn the torque converter and try to get the off-set hole and an adjacent hole both in view at the same time though the splash shield opening. Then rotate the engine and flex plate until you get a match to those two holes and slip the two bolts in loosely. Then turn the engine and insert the other two bolts - I can't see any way this should not work as long as you can see two bolts at once.
 
. The factory flexplate offset hole is easy to see, the hole is NOT centered on the tab, the converter, not so much. .

I actually forgot this - if flex plate has tabs which originals do, the off set hole is off set in the tab.
 
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