Technical Hemi parts id. Marine, Industrial, Big Dodge truck?

I take it as a marine 354. Some one doing the stamping didn't get the memo on what numbers he or she was to stamp on it.

 

Found on another site ---
M was Chryslers code in 1959
354 engine size in a big Dodge truck
Any thoughts?

 

That makes the most sense.

 

So the industrial/ truck engines came with gear to gear cam timing. This means that the cam rotates ccw.
Industrial/ truck engines can be converted to automotive style chain cam timing with standard rotation cam by changing the cam, intermediate gear, distributor and timing set. There is no need on these engines for special machining of the crank. I’ve never had my hands on a marine version, so I can’t speak to converting those.
The truck/ industrial engines have a m***ive cast iron timing cover with high water pumps. They come with the long snout cam. Depending on what you want to do for a timing cover and fuel pump drive, you need to be aware that the block has lower water holes on the front of the block, so later automotive chrysler timing covers won’t work.
As I brought up in an earlier post, the truck/ industrial cams are different because of the ccw rotation. The drive gear is hobbed opposite of an automotive cam to correctly drive the oil pump in the correct rotation.
This means the intermediate gear is also hobbed different, and the distributor has to now hold the gear in place unlike the automotive version. see picture for a comparison.

 

Good info Trendz. I picked up this block, crank, heads and not much else. No cam or timing cover.
1 set of 1733463 blue heads, adjustable rockers and Marine covers.
1 set of 1733463 yellow heads which I believe went with the M354 block.
This purchase was a mix of Marine and 354 Dodge truck parts.
I am figuring out the differences between Marine and Dodge truck 354's with help from you all.
Thanks!!!

 

That would seem to be right. The use code for a marine 354 is M45SP-3

 

Some truck blocks has the use code on the front face of the block on the driver's side to the right of the timing cover, some have random things stamped there.

 

Sepculation: There are reports of 1 or possibly 2 int. shafts used on 354s made while 392s were in production that are longer than those used on car 354s. Someone once said the dizzy shaft of either the B or RB would fit the '56 car hemi if put in an LA dizzy. If shaft is same diameter. It would seem to be a possibilty on the ccw engine, if set up where the dizzy does turn ccw, that a RB dizzy could be used, might take a shaft extension to fit, like what's done to use the LA & OEM int shaft on the 331/354 blocks.

 

My 58 Dodge 354 has a timing chain.
L8 D7 is the stamping.
I still think the M is for a marine block.

 

One concern I always have with marine blocks/heads is if they have seen salt water use. Those cooling p***ages might be extra crusty and possibly have thinner walls from salt corrosion. Check them out good before dumping a bunch of work into them.

 

I am working on Mallory flattops from a 392 and an RB now. I will take some measurements.

 

There have been several 354 engines found, both Hemi and Spitfire, that have an extra thick/fat rear main cap that dictates the use of the longer 392 intermediate shaft.

 

I probably didn’t make it clear in my description. The engines I’ve had(I’m sure there are probably exceptions) were industrial 331s. The cam is driven gear to gear which makes the cam spin ccw, but the distributor and oil pump spin cw, the same as an automotive engine. This is accomplished by the gear tooth angle being reversed (see previous picture) When they did this, the cam wants to lift the intermediate gear up off of the block bushing, instead of driving it down against the block/bushing. The distributors on these engines are lubricated and more robust than the p***enger distributors. This is to retain the intermediate shaft in position. In the picture, above the cams, is the special intermediate gear that comes in the industrial engines. The engines I have come with a single slotted oil pump drive. Later B &RB and LA all have a hex drive intermediate shaft to drive the pump.

 

I am finding more differences in these parts I will share.
Cylinder heads:
354 Dodge truck are yellow and have tapped holes in the bosses on each end of the heads.
Date code on these are 12-18
Marine heads are blue and the bosses on each end are not drilled and tapped
Date code on these are SP-2
Can anyone ID these date codes?

 

That oil pump makes the marine transmission's hydraulic shift possible. I have a complete setup myself.