Little update on my 80 slant

Idle Ender

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So, I finally had it all put back together and had it tuned just right and I have reason to believe I spun a bearing. Literally like 2 weeks later. Im sure the 3 speed non-overdrive and the 373 gears had the thing very high strung on the highway, which didnt help. It suddenly started knocking BAD while driving home on the highway. Hobbled it home with zero issues or loss of power, just really awful sounding. Since then Ive yanked the engine/trans out and have it sitting in my garage for a full inspection/rebuild. Taking this as an opportunity for a forced upgrade. New intake and exhaust manifolds, machine work, pistons, forged rods, small turbo for 10psi, and replace every wear item and gasket. Also researching ways to convert to an overdrive trans while I have it all out. I know there is a transmission thats almost identical to a 904 but with overdrive, I just dont recall the name of it. Any thoughts or experience with building up and boosting a slant?
 

Idle Ender

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20170427_235338.jpg
 

kkritsilas

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The A500 is the overdrive version of the A904/A998. I don't know if they came with a slant 6 bellhousing, though. I do know they did exist for the LA and Magnum V8s (same bolt pattern).
 

Idle Ender

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Ah, yes. A500. Is the V6 bolt pattern not the same as the slant? Ive heard of it being done with little issue on older Mopars, so I figure it is.
 

BudW

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They did not make an O/D transmission that will bolt behind a /6 (G or RG platform) – except for the A833 4-spd O/D standard transmission.

The V6 that Dodge used after /6 production quit, is 3/4th of a 318 (two cylinders lopped off).

There is a company who is (or was) modifying the A500/A518 (727 version) to fit the big block. What they did is cut off the bell housing off of an existing A500/A518 and a new bell housing bolts onto old case using the front pump bolts.

For a /6, that might fine. For a big block, 6 tiny bolts that hold the bell housing onto the transmission – seems like a big weak link.

On top of that, you will have to modify the transmission mount/crossmember as well as modify the floorpan of car to fit the bigger/longer transmission.

It would be a lot more cost effective and less time, to convert car to an A833 O/D 4 speed.
BudW
 

BudW

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A /6 with turbo – or even with fuel injection would run great and you would have plenty of room for “the stuff” under the hood.
The /6, however, is limited to transmission types that will fit.

The small block, on the other hand, has a lot more options. It also shares the same transmission bolt pattern as the new Hemi’s do, so one could put the new 8-speed automatic behind your small block, if one wanted to do so (again, transmission crossmember and floor pan will both need to be modified to fit). Even the 6-speed manual transmission could bolt behind your small block.

A 5.7L Hemi would be even more fun to drive – but they are not a direct bolt-in affair (a few here has done it).

I considered a new Hemi transplant, but also figured a big block would ultimately be more fun (for me).

A small block upgrade (or Hemi or big block upgrade) might net you more "smile" per buck spent, maybe. That is also not considering all of the necessary fabrications and trying to make things fit in places wasn't designed to go.

As far as that goes, even transplanting a 3.6l V6 with automatic transmission (from a new Charger), would leave you with a lot of power, extra space under hood and decent fuel mileage to boot – but, also, not a direct bolt in.
BudW
 

Aspen500

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The modern drivetrain in an older car can be a ton of work. Making it fit is the easy part. It's the electronics that cause the problem. Mainly interfacing between the new and old without having the instrument cluster module, body control module, ABS module, etc in the network. The newer the engine/trans, the harder it is. Some won't even crank without a BCM in place due to all the multiplexing and security on newer vehicles. Not meaning to deter anyone from doing it though!
 

kkritsilas

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I think that there are carb intakes for the Gen III Hemis, and I know that there are carb intakes for the Magnums. There are other issues (you would probably need to move to an electric fuel pump for either, and you would need to use an MSD Hemi-6 ignition system for the Gen III Hemi. If you have an small block transmission, that would bolt up; it may take some effort to get the transmission linkage to work out right.

I am of the belief that the Magnum swap is easier, as externally, the LA and Magnum V8s are the same, and will still give a pretty significant improvement in power, especially if you go with a 5.9L (360) Magnum. It is no harder to swap in a Magnum than an LA, and the Magnum V8s have significantly more power, use roller rockers (ie. no concern with ZDDP content in the engine oil) and a serpentine belt drive. There are also a lot places that state that the Magnum tolerances were much tighter than an LA engine. On the other hand, the Magnum heads do have a greater tendency to crack.
 

Idle Ender

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To clarify, I know doing a V8 swap would be the more practical choice as far as power per dollar. I just love the simple ruggedness of the slant and its quirky and simple design. Boost is more to pep it up a bit as a daily driver. I have an LT1 S10 build in the works for the go-fast. If for whatever reason the slant is toast, a magnum 360 is most likely the next course Id be taking.
 
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