More 8 bolt flexplate questions

SIZEMOREMK

Junior Member
I need an 8 bolt flexplate for our stock converter.

I have searched quite a bit on the flexplates, but I am still not sure what I need.

I have seen some threads where some flexplates had a different depth, others where the bolts holes didn't correctly line up on the crank, and others that needed holes enlarged.

Has anyone ordered one recently that fit the crank correctly and had the pattern for the stock converter?

I don't like the idea of drilling into flexplates.
 
The flexplates some had trouble with most likely came off of an 05+ Auto Mustang, which will not work.
 
I read extensively on this on svt - many auto swaps done on Cobras. That plate linked is what they use. JW the wheel also has an 8 bolt plate.
 
Ok, I found what I hope is the right one on amazon.

The PAX units are made by PRW from what I found around the boards.

So PRW 1828111 should equal PAX28111

I ordered this one:
http://www.amazon.com/gp/product/B004L2UM2Y/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

I'll report back if it fits or not.

I seen here in the forums where there were some bolt hole issues on some of the PRW units, I also see where the PAX units had similar issues in the reviews on summit's website.

Hope I get lucky!
 
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Ok, I found what I hope is the right one on amazon.

The PAX units are made by PRW from what I found around the boards.

So PRW 1828111 should equal PAX28111

I ordered this one:
http://www.amazon.com/gp/product/B004L2UM2Y/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

I'll report back if it fits or not.

I seen here in the forums where there were some bolt hole issues on some of the PRW units, I also see where the PAX units had similar issues in the reviews on summit's website.

Hope I get lucky!
nice research!
I'm going to order mine now, thanks!
even less at autoplicity:
Sub-Total: $77.88 Shipping: $8.00 Order Total: $85.88
 
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If that one don't fit right with misaligned bolt holes and such, there may be another option from B&M.

First I called B&M and they couldn't tell the specs of the unit and that it was discontinued. There are, however, quite a few online sources that claim they have it in stock.

Then I called Summit and asked for the converter pattern. They said it may take a day or so to find the info, but they called back today after they got one in-hand to measure.

According to the guy that measured it at Summit, the B&M 50341 unit is suppose to have both 10 5/8 and 11 3/8 converter patterns.

It is here:
http://www.summitracing.com/parts/bmm-50341
Note the picture is not right, but several other pics of this part number look different:

Here's another pic of the same part number:
http://www.amazon.com/50341-Chromoly-Flexplate-Modular-Engine/dp/B007T413OW

Neither of the pics I found look to have the smaller 10 5/8 pattern in the pics, but the guy that had one in hand said that is the measurement.

If the PRW unit I have is messed up, I may try this one.
 
If the bolt holes don't line up, rotate the flexplate (with the crankshaft stationary) until they do line up. :D
 
If the bolt holes don't line up, rotate the flexplate (with the crankshaft stationary) until they do line up. :D

Hey, RacerX, do you recall which flexplate you posted a pic of showing a difference in depth in relation to the stocker?

Do you know if that difference caused an issue?

Thanks!
 
SIZEMOREMK. Hope this helps. I used one from Rock Auto Part #F249 for a 5.4. Only after going round and round with performance auto for a month with a defective P.A.W. Flexplate. (spacing was way off) I had my trans and converter out 12 times thinking I had something misconbubulated lol. I was told sorry no refund or new flexplate. If I remember correctly the rock auto f249 has holes for both converters. I Also I just checked ebay under 5.4 flexplates (all 8 bolt I think) alot with multi converter holes. Hope this helps Walt
 
SIZEMOREMK. Hope this helps. I used one from Rock Auto Part #F249 for a 5.4. Only after going round and round with performance auto for a month with a defective P.A.W. Flexplate. (spacing was way off) I had my trans and converter out 12 times thinking I had something misconbubulated lol. I was told sorry no refund or new flexplate. If I remember correctly the rock auto f249 has holes for both converters. I Also I just checked ebay under 5.4 flexplates (all 8 bolt I think) alot with multi converter holes. Hope this helps Walt
what spacing was way off?
torque convertor holes for MM mounting?
 
I have that exact flexplate, fits perfectly
do you have the stock MM bolt pattern on your convertor?
I'm wondering if this is the disconnect - my aftermarket convertor has 2 bolt patterns, MM and regular CV I think?
 
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do you have the stock MM bolt pattern on your convertor?
I'm wondering if this is the disconnect - my aftermarket convertor has 2 bolt patterns, MM and regular CV I think?

Yeah my Circle D has dual bolt patterns as well , the PRW flex plate is also what Chris from Circle D sells as well.
 
Yeah my Circle D has dual bolt patterns as well , the PRW flex plate is also what Chris from Circle D sells as well.
from DirtyDog convertors: Marauder size
11.25 refers to the converter diameter meaning it will have 4 holes on a 10 - 5/8 bolt pattern
Crown Vic Torque Converter Bolt Circle:11.400 in
 
I have the 258MM 10 1/4" converter , the flex plate also fits stock bolt pattern converters.
 
SIZEMOREMK. Hope this helps. I used one from Rock Auto Part #F249 for a 5.4. Only after going round and round with performance auto for a month with a defective P.A.W. Flexplate. (spacing was way off) I had my trans and converter out 12 times thinking I had something misconbubulated lol. I was told sorry no refund or new flexplate. If I remember correctly the rock auto f249 has holes for both converters. I Also I just checked ebay under 5.4 flexplates (all 8 bolt I think) alot with multi converter holes. Hope this helps Walt
still wondering what spacing was way off? did you have a CV converter with the large bolt pattern?
You know, with any convertor/flexpate, especially aftermarket stuff, you need to put the convertor fully into the transmission, and slide out ~ 1/8" - any space between the mounts and flexplate at that point will need to have spacers take up. I have had to slide grade 8 washers between convertor and plate a dozen times. Is this the spacing you mean?

I have the 258MM 10 1/4" converter , the flex plate also fits stock bolt pattern converters.

Roger, that;)
this flexplate has enough holes to fit many convertors - should not be a crank hole or convertor hole issue:confused:
164 tooth flexplate internal balance
Features 10.5 in. and 11.5 in. Ford bolt patterns, and 10.75 in. and 11.5 in. GM bolt patterns.
Meets SFI 29.1 safety ratings
Available in either 6 bolt or 8 bolt crankshaft bolt patterns
6 bolt configuration commonly found on all Crown Victorias and Panthers, most Mustang GTs 96-04 and Mach 1s
8 bolt configuration commonly found on Mustang Cobras and in some 5.4 truck motors.
 
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