Technical 350 turbo 153 tooth flexplate question

I've got a 327 engine connected to a 350 turbo transmission. my original 153 tooth flexplate was flat. the new flexplate I bought has raised surfaces around the holes where the torque convertor mounts. I was told the recessed side of the flexplate goes toward the torque convertor?? the raised pads on the flexplate are on the not raised side... Hope the question is not too confusing. Which way does the flex plate mount to the crank... recessed side towards the crank or recessed side toward the pressure plate.
thanks for any help.

 

The pads that bump out will go to the converter.

 

You will want to make sure that you have to draw or offer up the converter to the flexplate after the trans is bolted to the block.

 

Yep, this is the side the convertor bolts to.

 

there should be a raised edge on the middle hole, that fits over the crankshaft...make sure the raised edge fits away from the crank flange, not towards it.

 

If your engine was a stick shift before remove the pilot bushing from the crank or it will cause the flex plate to crack...

 

Huhhh?

 

the last time I installed the flex plate I turned the recessed side toward the crank shaft. this flexplate had no pads where the convertor bolted. there was interferance between the starter and flexplate. I had to shim the aftermarket starter and still the teeth bottomed out and messed the flexplate up. I installed the new flexplate with the recessed side to the torque convertor, but the pads are facing the crankshaft. Now I have only half engagement on the flexplate teeth. Looks like once again I have to split the motor and transmission apart and turn the plate around..

 

Might make sure it's not the starter causing the problem?

We might be talking past each other as far as what direction is recessed, etc.

And posting pictures is a really good way to convey information.

 

This is the for sure way to know. That raised lip is pointing toward the transmission to word it another way.

 

The pilot bushing in the crank sticks out just enough to place the center of the flex plate in a bind and eventually causes hair line cracks that will destroy the flex plate and make a sound like you lost a bearing/I went thru this adventure.....

 

What your actually saying is this. Your pilot bearing wasn't seated properly or walked out causing you to have issue's. Because a pilot bearing that is left behind has never been a problem at all other wise.

 

The snout on the torque converter will hit some pilot bushings or some torque converters snouts have a design that will hit the pilot bushing. A guy may get lucky and get the combo that doesn't have a problem but my luck says that I will always get the combo that doesn't work and have to pull it back apart and pull the pilot bushing

 

^^^^^ I never had one hit. Lucky ! Thanks

 

I pulled the flexplate back out last night. turned it around to where the raided lip and convertor mounting pads were toward the transmission. DUH... Had to shim the mini starter with a .060 shim. works like a charm. thanks for all the help guys. Only took me 2 hours from start to finish last time. lol..

 

Good to hear you got it figured out.

 

Old Thread - but I have a new question.

Bought a project from an estate with what appears to be an 85 or 86 SBC 350 and potentially a rebuilt Turbo 350.
The combo is just sitting in the frame and nothing was hooked up due to owners p***ing.

The converter spins free and there is about a 1/4 inch gap to the flex plate.
Is this normal and can I try to tighten up the mounting bolts? Gotta buy the bolts - none were installed.

No starter came with it and the mounting bolts are 3/8 - not metric - if that helps identify the block and flex plate.
Flex plate has the raised area - is there an easy way to tell 153 versus 168 teeth?

 

Pictures help.

The 85 and 86 engines are different from each other...if you look where the end of the crankshaft is, the 86 and newer will have an aluminum housing that holds the rear seal.

The gap is normal.

Make sure you get the correct bolts/nuts for the torque converter. They're 5/8" long, and not available at hardware stores.

you should be able to measure the flex plate, it's either 12-1/2 or 14" diameter. When you get starter bolts, make sure you get the right ones, they're not available at hardware stores either.

 

Starter bolts, note knurling above the threads:
https://shop.advanceautoparts.com/p...FdyW5EUQl8tDekMRcZ8aAisbEALw_wcB&gclsrc=aw.ds

 

Chevrolet torque converter bolts:
https://www.amazon.com/Torque-Converter-Heavy-Duty-M10-1-50x15mm-TH-350/dp/B07HKR3ZPG

 

I verified the starter bolts are not metric today - bought the Dorman pack with 3 bolts.


I verified starter bolts are not metric and the auto parts store has torque converter bolts but I haven't bought yet.
Using some basic math of 12.5 x 3.1614 = 39.25 Diameter / 153 should be about .257 inch toot to tooth?

I have a working starter that came from a 88 350 700R4 but the mounting flange on that motor was 2 bolts and this block has 3 bolts so I ***ume I need to buy a new starter if I am successful mounting attaching the torque converter.

The gap in picture seems like may be too wide for the correct torque converter bolts?

 

That gap looks normal to me, but admittedly that was half a life ago.

 

The starter you have may or may not work. If the bolt hole bosses in it are the same length, it won't fit that flex plate. If one is shorter than the other, it will.

And your transmission is a 700, not a 350. And it takes special metric bolts, so you have another thing to chase.

 

I thought I measured the length but maybe was told it was a TH350.
Here's a side picture - I definitely I have spent a lot of time chasing missing parts and bolts.

 

that's definitely a 700, the servo on the side.. The MD8 logo on the bellhousing was the first hint, the lock up torque converter was the second.

 

So the 350/700R starter I have will probably work?

 

I don't know....I can't see it

 

No TV cable?

 

Johnny Gee would have an easier time explaining this very simple thing to this fence post it seems.
He explained it in explicit detail and forget the what transmission nonsense right not, for the starter that bolts to the block on a V8 small block all you are concerned about is having the correct starter to match the 153 or the 168 tooth flex plate/flywheel. Side by side for 153 tooth, offset for 168 tooth. Unless it is a specific heavy duty application I don't know of any Chevy V8 that bolts to the block with three bolts.