Ok you Magnum swappers here it is.

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TrailBeast

AKA Mopars4us on Youtube
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Just finished the major details and now working on the smaller ones.
This is my new 5.9 Magnum disguised as an LA smallblock, and at the same time I did a 904 to 42RHOD (A500OD)
I didn't actually plan on doing both at the same time, but just about the time I started getting ready to do the Magnum my existing 904 started making planetary gearset noises.
Within about two weeks the metal accumulating in the fluid started hanging valves in the trans and it didn't want to shift in the mornings until the fluid got circulating enough to rinse out what had settled in the valve body over night.
Buying the parts and a rebuild kit was really close to buying a used 42RH and a rebuild kit, so that is what I did.
While I was in there I added a stage 2 Transgo shift kit.

I don't want to go into so much detail that it gets tedious, but After just finishing this I can answer most concerns some may have over doing it, so feel free to ask if there is something I can help with.
As far as the trans being partially electrically activated (OD and converter lockup) I am not going to use switches on the dash that I have to turn on and off at the right times like most do.
I put together a kit for fully automatic shifting of ALL gears and am assembling that right now for 4th (OD) and converter lock. (you can see them on the back of the intake)
There is ONE place I found online that has a kit for this but they never got back to me, or even answered my email for over a week so I couldn't trust them so I built (put together) my own kit for this.
That companies kit has set shift speeds for those two shifts, and the one I made is fully adjustable so you can set your own shift speed preferences.

So here it is, a Magnum disguised as an LA smallblock in front of an 42RH overdrive.
EQ 62cc closed chamber Magnum heads (@9.1/1) with LA style intake bolt pattern, Oregon Cam grinders 214/224 at .50 with Hughes custom Magnum springs and accessories,
350+hp, 400+tq with a factory 1,800 stall converter.
400ft lbs at 3,500RPM's and runs just fine on 87 pump gas.
You can't see much of the trans in any of these pics, but that's good thing as the car goes I guess, but you sure can see those welded into the front subframe and crossmember subframe connectors. (2x3 .085 wall tubing)
. :D

MagnumswapLA.jpg


driverside.jpg


switches.jpg


SFconnectors.jpg
 
Well I've got to get mine back together and actually RUNNING first LOL

Did you get rid of the lockup converter or no?
 
Well I've got to get mine back together and actually RUNNING first LOL

Did you get rid of the lockup converter or no?

No it's still there, and will be on one of the combination trans pressure and vacuum switches so it will also be fully automatic depending on intake vacuum levels just like OD will be.
Today I am going to some onsite stuff and part of that run is on a 45mph stretch so I'll be testing the OD for basic function with an activation switch.
Once the testing is done OD and lockup both will be on their own settable pressure sensing switches so I can adjust at what speeds and throttle openings I want them to activate and deactivate at.
High enough governor pressure (determined by mph) will activate the ground circuits as the solinoids are keyed 12v all the time.
When they are switched on grounding the solenoid and activating the OD will be around 50mph and lockup at about 55.
Then if more throttle is given and the intake pressure drops to a certain point it cuts the power to both solinoids dropping back to 3rd gear like a normal 904 in high gear.
Let off the throttle, manifold vacuum comes back up and they are able to reactivate again (but only if at 50mph or over for OD, and 55 for lockup.)

The OD is .67:1 and then there is converter lock after that, so with my current gearing I should be at right about 1,600rpm at 80mph.
Let's don't even consider using OD manually and split shifting for a close ratio 6 speed automatic.:D
All it would take at this point is to manually control the OD lockup in between the normal gears.

Don't make me come up there and spend a weekend helping you with yours when it's ready. :D
 
Video. Or it's all a setup. LOL
 
Very nice set up I'm glad for you.

Thank you.
It's actually kind of amazing how exited one can get over a car and it's details. :D


Will you be making a kit we can buy I have a 42rh in my Dart

Probably not, but I can tell you what is needed and how to connect it all up.


That really looks good I'm buttoning up my swap also. I stayed with the la look.View attachment 1714933867

Man, you need to get in there and make a little bit of a mess of some kind.
It looks like a hospital room in that engine bay. :D


Video. Or it's all a setup. LOL

Not sure what a video can do that pictures can't unless it the sound.
I can do that if you really want me to.
 
I think that sounds really good. I hope you are happy with it.
 
Bet you still get an erection,driving it.....

Every time. :D
It's going to take awhile to get used to shifts after the normal 3rd gear, because I am still caught a bit off guard when it shifts.
After driving it for awhile I find leaving converter lock up disabled via the manual switch seems best, though I'm not really sure why it matters.
It doesn't go into lockup until 65 anyway, and I never use that around here.
Running down the road at 70 in OD without lockup is about 1,600- 1,700 RPM's and it seems to like that, and it only takes about 1/2 inch or less of throttle to do it.
It's a little hard to keep it under the speed limit above 65 in lockup.
I was driving along thinking about something else the other day, just kind of daydreaming and suddenly realized I was doing 97.
It tricks you because it doesn't sound like that fast.
 
It tricks you because it doesn't sound like that fast.

That right there is pretty funny!!!

Years ago, for about a year, I had a 81? Chev Caprice that had been the infamous diesel. Someone had swapped an Olds 350 gas in for the diesel. It must'a had about a .7 rear gear. Damn thing would do the legal speed limit (I think it was still 55 then) in first gear.
 
That right there is pretty funny!!!

Years ago, for about a year, I had a 81? Chev Caprice that had been the infamous diesel. Someone had swapped an Olds 350 gas in for the diesel. It must'a had about a .7 rear gear. Damn thing would do the legal speed limit (I think it was still 55 then) in first gear.

This trans has the low first gear set in it and I have dropped it into manual first at 40 and accelerated from there.
The shift kit had the option to change the valve in the valve body so you could go to manual first at any road speed, so if I am doing 40 and ratchet the shifter back twice and nail it that brings it well into the cam and frickin flys.
A couple of times from a dead stop I have nailed it pretty good and spun all the way though first and second till I let off at about 6k but alas, it's still a one legger (so far) unless I'm in a light left hand drift, and then it spins both :D
I swear when I get my gas bottle filed I'm going to weld it up. (It's only a 7.25 anyway so who cares)LOL
 
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