I have a problem...

I just got my converter and thought I would get a TCI Flexplate for added insurance. It turns out that the converter's threaded bolt holes are 3/8" x 16, while the flexplate just has a 1/2" hole for the bolt to go into. While that is fine and dandy that extra 1/8" is enough space for the converter to not be 100% locked together. I can not drill and re-tap the converter holes as there is not all that much material there to work with and it may compromise strength. Has anyone else experienced this or know of anyone who has?

 

The LS1 converter has an M10x1.50 thread, not a 3/8"x16. Also the TCI flexplate has 7/16" thru holes for bolting up to the converter. I am not saying this is a good practice, just clearing up the facts.

 

Thank you for the clarification.
The converter is a Fuddle 3000 2.0. I dont think that it is a good idea to install it with that large of a gap between the bolt and flexplate and am wondering what others have done to compensate.

 

If I understand you correclty the hole in the Flexplate is bigger than the bolt you currently have that screws into the convertor. If that is correct ARP sells a convertor bolt that has a shoulder in the location of the flexplate that takes care of that problem. I hope this heps!!

 

Do most people usually get new flexplates with new converters?

 

I'm getting a TCI also with my Yank converter...and new ARP bolts to go with it.

I wasn't aware there was a bolt hole mismatch problem? I'm pretty sure I would have heard of it before after researching in this forum for months...

 

I should probably pony up then to a new TCI flexplate then just using my stock plate. I have heard that I need to take a dremel to one of the holes on the stock flexplate to get the bolt to fit nice.

 

I've run into the same issue witht he TCI unit in my truck. Wondering whether I should install it or not. A strong shoulder bolt or an adapter in the flexplate would make me feel more comfortable with it. Both probably impossible to buy..... and I'm not a fabricator.

 

Does anyone know if there are any issues with bolting the flexplate to the engine?

 

I had 2 TCI converters with both bolt holes being different sizes. The standard SSF converter had (fatter) bolts where as to my billet cover TCI has way smaller (skinny) bolts. Not sure on the sizes as of right now. I also had to get longer bolts when bolting it up to the TCI flexplate on BOTH converters. I just went down the the local hardware store and picked up 3 new 8 grade bolts that where longer. My cousin who works at a trans shop and helped me with the install assured me that they would hold. He has seen bolts of that grade that actually tore flexplates apart before and didn't even break. He has more storys of that nature also....
I think with the stock flexplate it would be fine to use the bolts that come with the converter....

I know one bolt hole from the converter to the flex plate MUST be started first with the last 2 bolts going in second and third. I think the one that is started first is the more oblong bolt hole.

Also I am VERY displeased with my TCI flexplate right now as I have to pull the trans in the spring to retighten the bolts to the motor because the whole flexplate was coated, and around the bolt holes the coating has come off in a years time causing the bolts to be loose and it rattles like a ****. Thought I broke a piston skirt or something last fall and we where all over the car, it turns out that is what it was.
A good freind of mine told me they now do not coat around the bolt holes on the TCI flexplate.....so that is my luck....Figures....

 

I had my flexplate come loose because of the coating, when i tried to contact them they ignored me. They lost me as a customer forever

 

I called the 800 number on hte flexplate to ask about the difference in size between the holes and the bolts and the guy had no freaking clue. He told me that the holes were the proper size for the stock converter bolts, so I told him that they were't and he just said that is the only one we make.

The coating on mine is flaking in a few spots, from the rough life of sitting on hte carpet next to the computer. I guess I will sand off the coating around the bolt holes to make sure that I wont have any other problems.

Anyone know what size bolt is used to attach the flexplate to the engine?

 

Mine, bought just couple weeks ago, is painted gray. Not the black and white coating I've seen in pictures of others. I don't see an issue with flaking. I also looked at the hole size in the stock flexplate. They have a lot of slop in them also so I'm gonna bolt it up as is. Make sure I get it torqued right and put some locktite on them.

My TCI flexplate came with new bolts for the crank don't know the size but they fit.

 

The bolts to the crank are 11mm and ARP sells a bolt set for a stock flywheel that work great.

 

Here's an interesting task for you to try. Take a 1/2" bolt and stick it in a stock flexplate bolt hole, passes right through. In other words the stock bolt hole is the same size as the one in the TCI flexplate.

One other thing....I have owned two TCI SF converters, the old one uses the stock 8mm bolts, the newer one uses 7/16 bolts. With the 7/16 bolts you need to drill the oblong hole to 1/2".

And one other thing... old th350,400 TCI converters came drilled for 3/8 bolts to be use with a bolt and a nut. They also came with instructions to drill the converter holes to 7/16 when used with a TCI flexplate (since the TCI flexplate has 7/16 holes).

 

I have yet to remove the tranny to check this in person, which is why I was asking... But thankyou for confirming that the stock engine to flexplate hole is also 1/2", on my crappy tape measure, or 7/16" in actuality.

 

Thanks for the response. Mine is also grey, so I guess it will be good to go. I am going to try to find some bolts that have a shoulder on them, rumor has it ARP makes a set, so that everything will be nice and snug. Thanks again!

 

what is the part number for the arp bolts from the converter to tci flexplate and also the flexplate to the crank....i have a fuddle converter thanks

 

Ok...lets see. The bolt vs. hole size is a non issue. Sometime yes you need to oblong the hole, but fret not if the bolt is slightly smaller than the hole in Flexplate. Next thing, you can use M6 ARP Flywheel bolts for the flexplate to crank, make sure to check depth and have some small flat washers (preferable some ground face chamfered like the ARP kind, I used a SS Flat washer though). And before you install, take the fricken powder coating off the area surrounding the bolt holes, that crank and flexplate ones both. I used a die grinder and sanded both sides of the flexplate after having the powdercoating melt off and loosen the bolts twice!