torque converter to flex plate gap

[NHCharger]

Installing my 727 to a new used 440 I bought from a friend. New flex plate from 440 Source. New torque converter from Frank at Dynamic Converter. When I mated the tranny to the block there is a 3/16" gap between the flex plate and torque converter. My new ARP bolts only have 1/2" of thread. How much of a gap is too much? Should I install one washer to bring the gap closer or is 1/8" still too much? My FSM had no answers.
Thanks

 

[Virg464]

When I set mine up I was told you want 1/8" (that's with the converter pressed fully into the trans), which is what I had. The issue you want to avoid is pulling the converter so far out (to mate to the flex plate) that you don't have good engagement with the pump. I think you'll be OK, but I'm sure one of the local FBBO gurus will chime in words of wisdom.

 

[dvw]

I've run them from 1/16" to 3/16". You'll be fine. Using washers is a pain to get them in there. Measure the thickness of each washer if you do use them. Washer thickness varies.
Doug

 

[4mulas]

3/16 should be fine

 

[493 Mike]

Installing my 727 to a new used 440 I bought from a friend. New flex plate from 440 Source. New torque converter from Frank at Dynamic Converter. When I mated the tranny to the block there is a 3/16" gap between the flex plate and torque converter. My new ARP bolts only have 1/2" of thread. How much of a gap is too much? Should I install one washer to bring the gap closer or is 1/8" still too much? My FSM had no answers.
Thanks

Did you pull the converter forward as far as it will move? Did you lube the hub? There may be a problem with the interface/clearance. The flex plate cannot be sprung out of shape with bolts trying to pull the two together.
Mike

 

[GTX JOHN]

3/16 will be OK
As you shim the converter back with washer you screw up
the starter engagement to flywheel teeth.

 

[1 Wild R/T]

3/16" is fine, the convertor hub will have plenty of engagement...

Next thing to be aware of.. There is one bolt offset in the pattern... It's close enough that plenty of people have gotten three bolts in and the fourth bolt cross threaded...

An OE flex plate will have a small hole to index the torque convertor... I just went to the 440 Source site, theirs doesn't... You need to match up the bolt pattern either before installing or simply use one bolt, snug it up & rotate the engine looking at the other three locations before installing any more bolts..

 

[NHCharger]

Thanks for all the replies.
Yes I greased the snout of the converter with grease. Trans shop said to just coat the shaft in the tranny with tranny fluid, not grease. Dynamic told me to add one quart of oil into the converter before install.
I know that the bolt pattern is offset. Before I installed the flex plate I lined up the flex plate and converter on my work bench, ran all the bolts into the holes to make sure there was no issues, and marked the alignment with some white spray paint so it will be easy to line them back up once in the car.

 

[Don Frelier]

I use blue loctite on the converter bolts.

 

[toolmanmike]

Correct me if I'm wrong, You install the converter in the transmission and push it in all the way. Install the flex plate on the crankshaft and mate the transmission to the block. You then pull the convertor out to the flex plate and bolt it together. I've never had a "gap" or an issue.

 

[Don Frelier]

Correct me if I'm wrong, You install the converter in the transmission and push it in all the way. Install the flex plate on the crankshaft and mate the transmission to the block. You then pull the convertor out to the flex plate and bolt it together. I've never had a "gap" or an issue.

He's talking about the gap when the converter is fully seated in the transmision.
If it's really large then pulling it forward to bolt up to the flexplate reduces the engagement depth in the transmission.
If the engagement is too small then bad things can happen.
I've put a few together with probably 3/8" (stock engines) and never had a problem.

 

[zyzzyx]

All of what was said plus: You do not want the convertor pushing on the front pump impeller
because it will chew itself into shavings and chips! 3/16" is perfect!

 

[Dave6T4]

I once put an aftermarket higher stall torque converter into one of my cars. In short order, the converter seal started leaking, like, BAD. On pulling the trans and converter, it looked like the converter was built not using a Chrysler shell. The recess for clearance of the crankshaft bolt heads was not deep enough. There were "witness" marks on this recess area where the bolt heads were interfering. Depending on whether a flat area, or a pointed area of the bolt head was contacting the shell, the torque converter was not running true. This not only took out my seal, but also the pump bushing, and damaged the neck of the converter. My dealer exchanged this damaged converter with one from a different supplier and it worked OK. This condition from the first converter was not anything I could have anticipated.

 

[Lefty71]

Referring to your other (second post).... the gap here that people are describing is necessary to show that the converter is properly aligned with the oil pump drive gear (fully seated), so you that dont have any tension on that gear when you bolt the trans and motor together. Dont confuse tho, you should easily be able to pull that gap closed, by hand, without any converter bolts needed once the trans is bolted to the motor. If you can not, then there is a problem with the mating of the crank/flex plate/converter hub. You would need to check that dry fit before assembly, or pull it back down in your case.

 

[Mike67]

Just out of curiosity what is the minimum clearance from the head of the bolt to the block? I'm using ARP 5/16 TC bolts and have about .070-.080" & it scares the crap out of me!

 

[1 Wild R/T]

Just out of curiosity what is the minimum clearance from the head of the bolt to the block? I'm using ARP 5/16 TC bolts and have about .070-.080" & it scares the crap out of me!

They do run close.. But since the end play on the crank is .007-.010 it shouldn't be a problem... And if a bolt backs out you can always post about the horrible knock in your engine...I haven't seen one of those posts yet this week...

 

[Mike67]

They do run close.. But since the end play on the crank is .007-.010 it shouldn't be a problem... And if a bolt backs out you can always post about the horrible knock in your engine...I haven't seen one of those posts yet this week...

They didn't like the dust cover on it at first, had to dimple a couple of spots in where the beads were rolled. It gives me the willys looking at it though!!!
Thanks!

 

[1 Wild R/T]

They didn't like the dust cover on it at first, had to dimple a couple of spots in where the beads were rolled. It gives me the willys looking at it though!!!
Thanks!

Did you know there are different dust covers depending on which convertor bolt circle you have...

 

[Mike67]

Did you know there are different dust covers depending on which convertor bolt circle you have...

I did not, any info would be appreciated!

 

[1 Wild R/T]

I did not, any info would be appreciated!

I had a photo on my computer that showed it really well... That computer died... I've just been searching the web & couldn't find a good picture... There are plenty of covers that have straight reinforcements , those always are stamped so they extend toward the engine... But there are also plenty that have a curve stamped into them.. Those have areas that recess back toward the convertor, it the area that recesses is in the wrong spot you might have a problem.... So Mopar used two convertor bolt patterns and made two covers with the curve...