383, A sense of direction

Camtron

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Torque Flights go boom when the drum free wheels somewhere past 9000 RPM. It's possible to hit this because when the conditions are met it's going 2x engine RPM. The fix for it is to replace the factory drum with a billet steel one.

Improper burnouts (not starting in 2nd gear) and a damaged rear axle can cause the sprag to fail; which will cause the drum to free spin.

Am I getting this right guys?

My 518 still has the factory powdered metal drum in it. When it comes out for a refresh it'll get a bolt-in sprag and steel drum.
So, say a ATI 30 roller sprag vs. our stock 10 or 12 (whatever it is) and a billet drum (from pick a company) would make for some decent insurance if someone is looking at running a decent amount of HP through a SB trans?
Would that be correct?
This is what is included with the 904 BIY kit from, Cope:
BUSHING KIT
WASHER KIT
BLOCKER ROD
BILLET 4.2 LEVER
HD BAND STRUT
PERFORMANCE FRONT BAND
PERFORMANCE REAR BAND
LOW REVERSE BILLET SERVO
MULTI SPPRING PACK
DEEP STEEL OIL PAN WITH FILTER EXTENSION
OIL PAN STUD KIT
RACE REBUILD KIT INCLUDES: PERFORMANCE CLUTCHES, STEELS, FILTER, TEFLON RINGS, SEALS & GASKETS.
From there it goes over using a forward or reverse manual valve body depending on HP of the build.
Now, looking at the billet aluminum vs steel drum is where a big price jump happens.
$600+ for the billet aluminum drum alone.
 

BudW

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Note: I have no bad opinions on the A904 Family of transmissions.
I do think a person will need to find a way to install larger front pump bolts if you plan on using a big block bell housing and cutting the bell off of a A904 transmission. The A904 front pump bolts are only slightly larger than Phillip head screws used to attach inside A-pillar trim on.

I know a lot of people using A904 guts inside of an A727 so no issues there, either - other than some machining work will need to be performed (in some cases).

No experience nor have any friends using a non-Mopar transmission - so I have no comment (good or bad) there.

There are many A727 cases that have exploded - so there is an issue there. In most cases that can be avoided using quality rear sprag components when in high torque situations (mud bog, tractor pulling, high output drag racing, etc.), and a high quality drum - if the sprag does fail. There are a lot of articles about that and most transmission builders know about it. The average street driver will not experience this, though.
The sprag is designed to allow the rear drum to freewheel when in any gear but first gear. What happens is the sprag gets stuck "engaged" which allows a drum to rotate at a way-excessive RPM in 2nd gear (twice engine RPM might be correct - or 12k RPM when engine is at 6k RPM - but might be wrong on the speed, going by memory).
The term "hand-grenading" the transmission will apply, when that happens, for it makes a bloody mess of things.

BudW
 

BudW

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BUSHING KIT
WASHER KIT
- these two items "should be" a given on any quality rebuild
BLOCKER ROD
BILLET 4.2 LEVER
HD BAND STRUT - This can be a weak link
PERFORMANCE FRONT BAND
PERFORMANCE REAR BAND
LOW REVERSE BILLET SERVO
MULTI SPRING PACK
DEEP STEEL OIL PAN WITH FILTER EXTENSION - more fluid is always a very good thing for any automatic transmission.
OIL PAN STUD KIT - ?? why?
RACE REBUILD KIT INCLUDES: PERFORMANCE CLUTCHES, STEELS, FILTER, TEFLON RINGS, SEALS & GASKETS. - Use a quality rebuild kit (one from a known name-brand) and NOT one unmarked or from CHINA.

I do recommend putting a dab of sealant on the bottom side of trans pan bolts. A small dab does wonders on pan gasket leaks
BudW
 

BudW

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If you into racing, every ounce, no, gram of rotating weight reduction is a VERY BIG DEAL.
If for street usage/racing/dual purpose, quality steel parts is good for long lasting durability.

Again, all of the above (last 3 posts) are my opinion.

When I get ready to build my BB A518 - I will take plenty of pictures of these items of the what's and why's - but that will be awhile.
 

Camtron

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@BudW, thank you for the detailed and insightful posts. Truly appreciated. @Duke5A and @XfbodyX, thank you for the replies and bountiful information as well. I do genuinely mean it. I certainly mean no disrespect towards you fellas.
I thought I even mentioned in a post that, I do regularly apply the things you’ve all shared on here and that I’m actively learning about this stuff, hence I ask questions and some times say things that just, don’t add up to you more knowledgeable individuals.
With that said, I’m also not trying to copy anyone’s build particularly (though @dukes old YouTube videos of his 5th Ave are a legit reason I decided to buy the car) And I don’t feel I’m trying to reinvent the wheel, I mean multiple companies make the parts to do this very thing. Clearly somewhere out there, people are doing this Combo.
In my head, which again, I’m still learning this stuff, a well built performance transmission shouldn’t have that great of energy traveling through the physical bell house and case itself, the energy should be going through the inner workings and moving parts of the transmission...it’s when those said inner moving parts fail and then exert that energy onto the case and bell house that you run into problems. Does that sound correct?
And that then brings me back to, why a small block trans built for 500-600hp/lbf-ft performance use with quality parts would suddenly be so useless behind a big block of similar power output?
We also established that this CRT adapter kit uses a new flywheel assembly to replace the flex plate and requires a new torque converter w/o ring gear, so it’s not quite like the adapters with bushings/spacers and block clearancing like you guys mentioned and were familiar with.
Im just working ideas, nothings set in stone.

...I would have expected this reaction if I casually said, “ I’m doing a 4 rotor Wankel build with sequential transmission”. Man, that would be neat.
 
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Oldiron440

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A good drum can help but they still let loose , a 727 can blow in the burnout box, on the hit and are dangerous to pedal.
cuda-xmsn-4.jpg
cuda-xmsn-3.jpg


I believe it's ATI that has a T400 case that bolts directly to a BBM, there are several companies who have a cut 400 case with a super bell. As you can see a 727 explosion is no joke and there's no power level that is safe, it can happen to a completly stock car. I'm going do the swap before my grandson starts running the Volare.

On the interior shot you can see the shredded trans blanket, the driver is lucky to have his feet.
 
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Camtron

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A good drum can help but they still let loose , a 727 can blow in the burnout box, on the hit and are dangerous to pedal.
View attachment 46764View attachment 46765

I believe it's ATI that has a T400 case that bolts directly to a BBM, there are several companies who have a cut 400 case with a super bell. As you can see a 727 explosion is no joke and there's no power level that is safe, it can happen to a completly stock car. I'm going do the swap before my grandson starts running the Volare.

On the interior shot you can see the shredded trans blanket, the driver is lucky to have his feet.
So you’re saying that with what you’ve seen, you wouldn’t even put your grandson behind the wheel of a car with a 727? Powerful statement. I’ve only seen the aftermath of one transmission exploding. My aunts 2003 Subaru Outback. Looked about the same as your photo.

I honestly don’t think my car will ever see a track or burnout box. I honestly get anxiety thinking about it. Have never been around it. My father in law used to regularly take his stroker 65 mustang to Great Lakes Dragaway, but he hasn’t been in years and has little interest in my car. We do get along, he just doesn’t care about a “80s shitbox”.

It’s weird, right before he stopped racing the car, really driving it all together, he had a custom 3 speed trans and rear end built by a neighbor of his who runs a corvette performance shop. I don’t even think the cars seen enough break in miles since he had them done about 3-4 years ago. I almost think he’s nervous to really drive the car hard because he’s always had to baby it and doesn’t want to risk the money/parts in the car now he’s gone through 3 rear ends and transmissions since he first built his car.

F026AF5C-FF59-4AE9-9620-C27301FA759A.jpeg


E52FE1C2-BCC1-4D47-A178-529D7E785B26.jpeg


1F8DB9E6-81F8-47E1-A587-354E982789DF.jpeg
 

Duke5A

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So, say a ATI 30 roller sprag vs. our stock 10 or 12 (whatever it is) and a billet drum (from pick a company) would make for some decent insurance if someone is looking at running a decent amount of HP through a SB trans?
Would that be correct?
This is what is included with the 904 BIY kit from, Cope:
BUSHING KIT
WASHER KIT
BLOCKER ROD
BILLET 4.2 LEVER
HD BAND STRUT
PERFORMANCE FRONT BAND
PERFORMANCE REAR BAND
LOW REVERSE BILLET SERVO
MULTI SPPRING PACK
DEEP STEEL OIL PAN WITH FILTER EXTENSION
OIL PAN STUD KIT
RACE REBUILD KIT INCLUDES: PERFORMANCE CLUTCHES, STEELS, FILTER, TEFLON RINGS, SEALS & GASKETS.
From there it goes over using a forward or reverse manual valve body depending on HP of the build.
Now, looking at the billet aluminum vs steel drum is where a big price jump happens.
$600+ for the billet aluminum drum alone.

You don't need an aluminum drum. Those are race pieces for the guys that are chasing every last bit of parasitic loss in their drive trains. Get the billet steel one.

Also, don't bother with deep steel pan and stud kit. Instead get the Summit deep cast aluminum pan and use the bolts it comes with. I hate steel transmission pans.
Summit Racing SME-1009 Summit Racing™ Aluminum Transmission Pans | Summit Racing
 

Duke5A

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The drum is the grenade if it spins fast enough, but it won't spin any faster than (engine RPM * first gear ratio). All 727 transmissions have a 2.54:1 first gear. It's easy to spin a factory drum faster than it's limit of about 9k RPM. The billet steel is something like 15k. Not impossible, but highly unlikely. I'd also run a rev limiter on your motor. 5.5k RPM is what mine is set at. Doesn't need to spin any faster as it's done making power by then anyhow.
 

Camtron

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The drum is the grenade if it spins fast enough, but it won't spin any faster than (engine RPM * first gear ratio). All 727 transmissions have a 2.54:1 first gear. It's easy to spin a factory drum faster than it's limit of about 9k RPM. The billet steel is something like 15k. Not impossible, but highly unlikely. I'd also run a rev limiter on your motor. 5.5k RPM is what mine is set at. Doesn't need to spin any faster as it's done making power by then anyhow.
Good info. I’ve actually really wanted to get my hands on a, Rev-N-Ator (anyone hear of it or use one?) they’re a Mopar ignition module look a like with built in rev limiter and come with a matched coil to eliminate ballast resistor use (I know there’s other means of getting rid of the ballast resistor) however they haven’t been available since the start of Covid. Will likely just end up going with a MSD box purely for availability factor.

46401AB0-EA82-4F1D-800A-708FD25F2A98.jpeg
 

Oldiron440

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So you’re saying that with what you’ve seen, you wouldn’t even put your grandson behind the wheel of a car with a 727? Powerful statement. I’ve only seen the aftermath of one transmission exploding. My aunts 2003 Subaru Outback. Looked about the same as your photo.

I honestly don’t think my car will ever see a track or burnout box. I honestly get anxiety thinking about it. Have never been around it. My father in law used to regularly take his stroker 65 mustang to Great Lakes Dragaway, but he hasn’t been in years and has little interest in my car. We do get along, he just doesn’t care about a “80s shitbox”.

It’s weird, right before he stopped racing the car, really driving it all together, he had a custom 3 speed trans and rear end built by a neighbor of his who runs a corvette performance shop. I don’t even think the cars seen enough break in miles since he had them done about 3-4 years ago. I almost think he’s nervous to really drive the car hard because he’s always had to baby it and doesn’t want to risk the money/parts in the car now he’s gone through 3 rear ends and transmissions since he first built his car.

View attachment 46768
The manual valvebody can exacerbate the problem with the forward coast in a first gear or all three. The problem is that the slack needs to be taken up before applying power or the case will be opened up.
The first time I saw a TF go off was at a strip in Wisconsin on a fairly stock Duster.
 
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Camtron

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Good thing I didn’t order that cam kit for the 5.9Mag from Hughes engine. Dave just sent me an email that all his customers orderers are on back order so any parts that do show up are already spoken for; and he has no ETA for any incoming parts...still doesn’t have the intake gaskets I ordered about a month ago. Thank goodness for, RockAuto.
 

Camtron

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Cleaning the garage turned into pulling the heads off the 5.9mag. It’s a low mileage engine driven by a little old lady, but the last two sets of heads I had pulled at the junkyard, had the typical cracked water jackets. I needed to be sure I wasn’t heading into the same issue.
No cracks to be found. Plus now I have a reason to replace valve guide seals and head gaskets, ect...and now the engine should easily last until the stroker build comes together.
Think I’m going to paint the block Chrysler Corp blue, the tins black and the heads and intake will be/look aluminum. Not 100% sure, but I like how it looks in my head.
 

Camtron

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Damn. My lung is too far gone. Get to have the upper lobe of my right lung removed, April 12th. Just when I thought I was about to make a little progress on the car too.

Oh well.
 

Camtron

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My buddy’s going to drive up on the 2nd and help me knock out the converter and engine swap.
Figure the two of us together should be able to knock it out in a afternoon. Give me a week to drive the car around a little bit.
Have the car together with a solid engine incase my wife has to quickly sell it. Hopefully I get to keep it for some more good years, lol.

Oh well. Such is life.
 

Camtron

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Spent 13 hours in the hospital yesterday getting the bleed in my lung under control; nearly drowned in my own blood when I went to sleep. Fortunately, I’ve been teamed up with one of the better Thoracic surgeons in the country and he’s moved my surgery date up to, April 4th instead of the 12th.
Today I gotta go to my wife’s shop and hang some cabinets and shelves. Try to get out to the garage later tonight and finish buttoning up the Magnum for the swap.

Just trying to keep on keeping on. Lung issues (as I’ve learned over the last few years) are the f*#&ing worst; but doing nothing doesn’t help. Gotta keep moving, breathing and coughing sh*t up. It’s been a tough game to play.
 

Sub03

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Sad to hear about your lung problems Cam. Good luck with the surgery, get well soon.
 

Camtron

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Surprise phone call this morning moving my surgery up to today. See y’all on the other side.

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