I purchased your Chevrolet TH350 non lock-up, w/ 6" tail shaft (P/N 311038) transmission w/ a converter (P/N 241538). It is being mounted onto a 85 SBC 350 crate engine. When I went to mount the transmission it had a gap of about a 1/2 inch from the flywheel to the mounting pad on the converter. I'm only able to get a couple of threads of the bolts into the converter because of this issue. I believe I have a flywheel of a car that had lock-up would this be my problem. Or is it the years of the converter not matching the year of the crate motor. My question is what flywheel from TCI or a year and make of a vehicle that I could get one from a local part store that would fix my problem with the clearance issue.

Transmission
http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=TC&Product_Code=311038

Converter
http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=TC&Product_Code=241538

You will need to get longer bolts and add washers, the same number on each to keep the balance, between the flywheel and t/conv to pull the conv forward about 1/8 inch.

Normally, a gap of 1/8 inch is normal when using stock eqt. Then it gets pulled forward, you can reach in and manually pull it forward to meet the crankshaft and bolt it together.

If you were to do this to your set-up, the conv would come out of the oil pump and after you got it all together, added oil, lowered the car, you would find it would not go anywhere because of no oil pressure.

I do suggest looking at the flexplate to make sure the it is installed correctly. The bosses the t/conv would bolt onto, are raised and are even with the ring gear side. This raised boss goes toward the t/conv.

Oh, welcome to the Club!

if not mistaken, the flywheel is on the crank backwards...i dont think you can bolt a later model flexplate to the earlier crank...physically wont fit...but the converter would bolt up to either new or old style flexplate on their respective motors...everett`s right, the converter will come out of the pump dogs, and wont make any pressure if you try to use it like you have it...definately get the flexplate thing straight before going any farther...i prolly wouldnt use any spacers between the flexplate and converter...i`ve seen too many crack from being loose...any spacer in there will reduce clamping force and possibly surface area, which would result in a knocking sound, and possibly damaging the flexplate...jm2c...

what crate engine did you buy. part number of engine is better.do you got 1 piece rear main or 2?

what crate engine did you buy. part number of engine is better.do you got 1 piece rear main or 2?

I have this engine I ordered from jegs.
http://www.jegs.com/webapp/wcs/stores/servlet/product_10001_10002_752506_-1_10763

The way I have it set-up know is with longer bolts and washers. I was told not to do this, so I havent been driving the car.

You can shim it out, but only to a point. If the hub on the converter comes out of the crank, you will have issues. I had a converter that I used two grade 8 washers (about 3/16 total) on each pad to achieve the required spacing to the flex plate, and it worked fine.

so the flexplate is the same for a l/u converter and a non- l/u?
i am doing mine today also and the new motor had a 700r, now bolted to my t350.i had this gap also. my converter is not threaded just thru-bolted (3 bolts) the raised part of the flexplate is facing the right direction. i bolted it up and pulled the converter to the motor. i am not ready to start it yet so i dont know if i pulled it out of the pump.

i didnt think anything of it until i read this post. now i think i may have goofed.
thanks for the help.

There's no loss in clamping. Just use the same number/metal of washers to shim on all bolts.

Check for a burr on the converter/flywheel. They should fit flush (motor/tranny) if not there's a reason.

whether or not there is a loss of clamping force due to reduced pad size or not i`m unsure of...but there is a problem inside the bell housing...of that i am sure...i`m not trying to argue with you everett, because obviously you are a very knowledgable guy, but i respectfully disagree with you on the whole washer thing...figure out the root of the problem rather than putting a band-aid on it...so what would make the space diff in the bell???one piece rear main crank with a old style flexplate???or vice versa???maybe a chinese crank with the wrong offset on the output flange???chris, is the output flange on your crankshaft round, or oblonged with an odd shape???(no slams or spiteful comments were used to harm any egos during the production of this post):noway:

Mike, no problem with the discussion. Others ideas are always good to listen/read.

Flexplates from a 1-piece crankshaft have a smaller bolt circle than 2-piece f/plates at the crankshaft flange, so one plate design will not bolt onto the other crankshaft.

The flexplate may be installed backwards, but I think the plate would be forced into a saucer shape due to the chamfer of the ID on the plate and the radius of the crankshaft. The plate should be flat after bolting up and tightening the flange bolts with the mating bosses, those stamped in the hub, towards the rear of the car. This places the t/conv flush with the back side of the plate. If he is using the original f/plate, looking to see the lockwasher marks on the bolt pattern would be an indicator as to the side facing the rear or to the trans.

He has an aftermarket convertor and the oil pump drive may be at a different height than original t/convertor. Or the conv lugs may be at a different height compared to OE conv. Action would require removal of trans & conv and lay together both of them side-to-side and check with a straightedge.

Who knows, there may have been this much distance when the initial separation took place of OE equipment and it was not noted, happens all the time, even to me.

An easy check to see if the t/conv comes unplugged from the pump is to pull the conv towards the engine all the way to meet the crankshaft, turn the conv 90*, and push onto conv to see if it sinks back into the trans. If it does, then maybe the drive and pump mating are okay. If the conv does not sink, then it tells you they have become disengaged. Chris should do this several times just to make sure of engagement.

No rubber bands or spitballs were thrown during the writing of this post.

This is normal when using an aftermarket or rebuilt converter (even if you buy one from GM it will be remanufactured).

The proper fix is to use a flat ground washer(s) to achieve proper converter engagement in the pump.

You want 1/8-3/16" movement out of the pump to the flexplate. If you have more than this you need to shim it so that you don't pull it out too far.

well that is totally new to me, so i stand corrected...we`ve got aftermarket converters all over the shop but all of them high end, so maybe thats the diff...idunno...i`ve got converters from b&m, dynamic,hughes, and stockers from dean transmission, and this is a first for me,so thats where i derived my thoughts...the backwards flexplate thing would be difficult to do for sure, but i have seen it before...(spent alot of time in a junkyard...lmao...)you see some pretty funny stuff working in a yard...i did when i was young, and it was a hoot!!!anyway,if using the washer thing, double check everything before re-installing into the car...

well that is totally new to me, so i stand corrected...we`ve got aftermarket converters all over the shop but all of them high end, so maybe thats the diff...idunno...i`ve got converters from b&m, dynamic,hughes, and stockers from dean transmission, and this is a first for me,so thats where i derived my thoughts...the backwards flexplate thing would be difficult to do for sure, but i have seen it before...(spent alot of time in a junkyard...lmao...)you see some pretty funny stuff working in a yard...i did when i was young, and it was a hoot!!!anyway,if using the washer thing, double check everything before re-installing into the car...


B&M isn't a high end converter IMO...
All converters are built the same way.

When they are remanufactured (and almost all are including "high end" pieces) they have to be cut apart. There is some material lost in the process, then the mounting pads may be trued up taking away some material.

When they are all welded back together the overall height is held by the machine that welds it back together.

I've installed $1200+ converters that needed to be shimmed.

well i know my flexplate is bolted correctly because when I saw the space difference i made sure. The converted is installed correctly and it is engaged and the is very little play when I push forward and aft on it so its not popping out. Its just the pads on the converter and the flexplate are not close enough to get the bolts I was told to use. So i used some longer bolts and washers. I saw a shim kit to use on the flexplate instead of using longer bolts would this be better of do yall think the washer is just as good.

Use the center hub to locate the f/plate, then pull the f/plate to meet the t/conv and bolt it.

Just be sure the f/plate is position correctly for full starter pinion engagement and for clearnce when starter is not in use.
This is why they call it a flexplate.

B&M isn't a high end converter IMO...
All converters are built the same way.

When they are remanufactured (and almost all are including "high end" pieces) they have to be cut apart. There is some material lost in the process, then the mounting pads may be trued up taking away some material.

When they are all welded back together the overall height is held by the machine that welds it back together.

I've installed $1200+ converters that needed to be shimmed.
all the high end converters i`ve used have been one offs from dynamic transmissions...harold builds and dyno`s them on site...he builds the high end stuff with new cases as far as i know, but also rebuilds and "tunes" used converters...b&m isnt a high end converter imo either, but i`ve never had to shim one...thats what i was saying...stuff from dean costing 150 bux has never given me problems...i`m not discounting your poinion at all...i`m saying its never happened to me, and thats why i piped up...and i did say "i stand corrected"...lol...

hmmm I have never had to shim a torque converter ever either first time i have heard of it... I have more experience with manuals but i have seen my share of autos and never used a shim on the converter .... hope i never will... if your going to shim the converter might i suggest a good strong bolt g9 (fine thread) would probably suffice and dont forget the loc-tite and lock washers! I would think this would be the weak link connecting the engine to the transmission.

so the flexplate is the same for a l/u converter and a non- l/u?
i am doing mine today also and the new motor had a 700r, now bolted to my t350.i had this gap also. my converter is not threaded just thru-bolted (3 bolts) the raised part of the flexplate is facing the right direction. i bolted it up and pulled the converter to the motor. i am not ready to start it yet so i dont know if i pulled it out of the pump.

i didnt think anything of it until i read this post. now i think i may have goofed.
thanks for the help.

hmmm I don't think I would have done this... How big was the gap? I think I would redo this with some longer bolts (if needed) and some g8 washers!

I think your flexplate is on backwards
this is the correct way it goes.
(notice the raised mounting points.)
http://webpages.charter.net/harrycoon/100_0265%20(Large).JPG

I guess I answered his question lol

The notches for the pump tangs are about 1/2" deep. Sounds like something is wrong. At 1/2" the convertor would disengage from the pump.

I think your flexplate is on backwards
this is the correct way it goes.
(notice the raised mounting points.)
http://webpages.charter.net/harrycoon/100_0265%20(Large).JPG
Sorry been out of the country. Mine is mounted that way.

can someone tell me a year and make of a car that would work with my tranny and engine? Im just going to go to the parts store and get a new flywheel and torque converter and see if it matches up better.

I would suggest a 70-85 350 CID (neutral balance) 153-tooth or 168-tooth flexplate.

Measure the diameter of the existing f/plate, it will be 12.5(?) inches (153-tooth) or 14 inches (168-tooth). Get a f/plate with a dual mounting pattern for the t/conv.

No lock-up conv for the trans.

i would reccomend the 168 tooth flexplate...it will turn the engine over easier as it is larger...this is especially important when running alot of compression and even alot of timing...