A999 Transmission mated to a 73 340 motor

-
ChrisRom

ChrisRom

Well-Known Member
Joined
Mar 25, 2018
Messages
56
Reaction score
17
Location
Columbia, TN
Hello,

I have a 65 Dart and I swapped the /6 in for a 340 motor I had in my garage from an earlier project.
The 340 is a low compression '73 externally balanced. It has the proper balancer up front.
I installed an A999 behind it with neutral TQ and a B&M flexplate for a 340. This flexplate is meant for a A727 behind a 340 according to their website.
Do you guys know if bolting this flexplate to an A999 is a problem? The bolt pattern is the same.
I drove the car around the block and it seems it has some vibration. Just trying to eliminate some of the gremlins....

162263357_10157844560621475_4791020173601977139_n.jpg


161462236_10157844560571475_6074425980915369362_n.jpg
 
the 999 was never put behind a 340 and there may not be a correct flex plate for that ~ that could well be the source of the vibration ~ exactly which flex plate are you running? B&M 10230 And which TC? Of course vibration can be a lot of things... nice car BTW! :thumbsup:
 
lilfontleroy said:
the 999 was never put behind a 340 and there may not be a correct flex plate for that ~ that could well be the source of the vibration ~ exactly which flex plate are you running? B&M 10230 And which TC? Of course vibration can be a lot of things... nice car BTW! :thumbsup:
Click to expand...

I am using the B&M 10235 which is for externally balanced 340 with 727 behind it.
 
If the bolt pattern on the converter alings with the flex plate your good to go. The plate has no clue as to what transmission is back there it’s just for balance.

The 999 is a great trans and with the low 2.75 1st gear ratio lends itself well to cars with numerically lower gear ratios.

You have the right balancer?

Cliff Ramsdell
 
The 10235 is for the 727 but in some cases will work on the 904 series. The 904 flex plate is a smaller outside diameter and does not have the big converter bolt pattern on the outside edge.
Sometime if you use the 10235 with a 904 it will rub against the starter.
 
brian6pac said:
B&M doesn't balance them ? 10235 is correct for B&M
Click to expand...
But not correct for an A904/999. The balance is right, but the larger diameter (so it can use both 10 and 11" convertors in the 727) often rubs in the smaller trans., which is why it specifies 727.
Jadaharabi said:
Sometime if you use the 10235 with a 904 it will rub against the starter.
Click to expand...
Which brings up a good point- the 10235 could be rubbing, and the scallop makes it feel like a vibration.
 
Jadaharabi said:
The 10235 is for the 727 but in some cases will work on the 904 series. The 904 flex plate is a smaller outside diameter and does not have the big converter bolt pattern on the outside edge.
Sometime if you use the 10235 with a 904 it will rub against the starter.
Click to expand...
Thank you.
I had the rubbing against the starter when I first installed the transmission. I put couple of washers between the bellhousing and the starter bolts. The starter still engages abut there is no more rubbing.

This is a cruiser for my wife. I don't think the engine will ever see anything above 3000-3500 rpm.
The rear end is a 8 1/4 with 2.94:1 for easy cruising.
The only other problem I have with it is the radiator fan. I had to use a fixed/flex fan because of the lack of space and it is quite noisy, like a jet when it goes over 2000 rpm. I can do an electric fan but I like the security of the mechanical ones.
 
ChrisRom said:
I drove the car around the block and it seems it has some vibration.
Click to expand...
Narrow it down- does the vibration occur only when you are driving (moving), or anytime the engine is running (neutral, park)? Does the vibration increase with engine rpm, or does it increase with forward speed? Or is it a constant regardless of forward speed or engine rpm?
ChrisRom said:
The only other problem I have with it is the radiator fan. I had to use a fixed/flex fan because of the lack of space and it is quite noisy, like a jet when it goes over 2000 rpm. I can do an electric fan but I like the security of the mechanical ones.
Click to expand...
Nothing wrong with a fixed/mechanical fan- like you say, they can be a bit noisy at times, but with the space limitations in an early A, ya gotta do what you gotta do. I'd be a bit leery with a flex fan though, especially the cheaper ones. Lots of horror stories out there.
 
Professor Fate said:
Narrow it down- does the vibration occur only when you are driving (moving), or anytime the engine is running (neutral, park)? Does the vibration increase with engine rpm, or does it increase with forward speed? Or is it a constant regardless of forward speed or engine rpm?

Nothing wrong with a fixed/mechanical fan- like you say, they can be a bit noisy at times, but with the space limitations in an early A, ya gotta do what you gotta do. I'd be a bit leery with a flex fan though, especially the cheaper ones. Lots of horror stories out there.
Click to expand...

It vibrates in park/neutral, anytime the engine runs. I am thinking either balance, engine mounts, transmission mount.... hopefully nothing else more "major".
Also, this car was never meant to have a big engine in it. It is a small mid 60's car. Maybe it is just shaking from the torque of the motor.....
 
ChrisRom said:
It vibrates in park/neutral, anytime the engine runs. I am thinking either balance, engine mounts, transmission mount.... hopefully nothing else more "major".
Also, this car was never meant to have a big engine in it. It is a small mid 60's car. Maybe it is just shaking from the torque of the motor.....
Click to expand...
True, everybody's definition of "vibration" could be a little different- could be as simple as a slight misfire, or a bum valve/lifter/cam lobe and not a mechanical vibration... sounds like you've got a bit of digging to do. Good luck, though- she'll have a sweet little ride once you get the bugs exorcised!
 
What torgue convertor are you using?
Some have weights welded to them.
 
You must log in or register to reply here.
-

Back
Top