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ok Engine swap questions from 318 to a 360 swap... A few small questions for the experts...

R

Rendered Safe

New member
Hello all,
I am thinking about swapping my blown 1979 chrysler marine 318 reverse rotation for a remanufactured chrysler 360 reverse rotation.

I guess my question may seem dumb to most of you , however I need to ask, having kids in and going to college makes things kind of tight around here these days...
so anyway..

Are all of my parts interchangeable from my old 318 to the remanufactured 360?
I mean valve covers, manifolds(intake and exhaust),oil pan,bell housing, etc. etc.
Can somebody please let me know what is and what is not interchangeable please...
Thank you for your time,
your help will bring me one step closer to a new engine......
Thanks again,
Eric
 
It's far more difficult than you are expecting. Sorry.

The 318 (and 340?) are internally balanced engines. That means the flywheel and damper are balanced. Not so the 360; it's an externally balanced engine, meaning the damper pulley and flywheel are deliberately unbalanced. (The motor balance is achieved via that plus balancing the crank internally.) So, you'll need 360 parts for that.

The oil pan is different, but if you get it with the 318, and it's a marine pan (cast AL) that will not be a problem.

Finally, the side mounts are slightly different. I'm told they can be modified, but be aware it's not drop in.

Jeff

PS: For a cruiser, the 360 has a TON more low end power than a 318.
 
I'll preface this by saying that I'm not a Chrysler Marine Engine expert.... not by any stretch of the imagination.
Jeff and a few of the other guys will be able to offer far more help than what I'm able to.



.
fastjeff said:
It's far more difficult than you are expecting. Sorry.

The 318 (and 340?) are internally balanced engines. That means the flywheel and damper are balanced. Not so the 360; it's an externally balanced engine, meaning the damper pulley and flywheel are deliberately unbalanced. (The motor balance is achieved via that plus balancing the crank internally.) So, you'll need 360 parts for that.
So Jeff.... if Eric can purchase a 360 with these parts..... he'll be OK.... correct?


The oil pan is different, but if you get it with the 318, and it's a marine pan (cast AL) that will not be a problem.
Jeff, you're suggesting that the 318 oil pan may work if it's one of the Aluminum Marine units????


Finally, the side mounts are slightly different. I'm told they can be modified, but be aware it's not drop in.
What all is involved?



PS: For a cruiser, the 360 has a TON more low end power than a 318.
Eric's boat is a 26 foot SDN F/B boat.... and is why I suggested the 360 to him.... of which he was already thinking about anyway.
This boat with the 318 would be underpowered, IMO.
Click to expand...


Questions for Jeff and/or you other Chrysler guys:

What piston profile will typically be found in the Chrysler 360 Marine Engine version?
(I have a reason for asking!)

One rebuilder mentions "Hypereutectic" dish piston in their 360 Reverse RH Rotation engine specs.
We all know that "hypereutectic" refers to the aluminum alloy (high silicone content).... but what do they mean by "dished" piston?
Full Dish... or partial dish...... just exactly what can Eric expect?



Transmission and engine rotation:

Eric's boat is using a Reverse RH Rotation Engine "flywheel forward" installation, with a V drive transmission.
He has not yet posted pictures of the transmission.

What, if any, V-drives are "oposite of engine rotation" capable?
In other words.... what is the chance of his transmission being capable of using a Std LH Rotation Engine?
This may save him a few bucks!

Lastly... Ignition advance curve graph:

I know that we've gone round and round on this over the last few years.... and have kept coming up empty.

Has anyone to date been able to find the OEM Marine advance curve graph for the Chrysler Marine Engines??????
Not just BASE advance.... and certainly not the Automotive specs.
I'm curious!



.
 
fastjeff said:
It's far more difficult than you are expecting. Sorry.

The 318 (and 340?) are internally balanced engines. That means the flywheel and damper are balanced. Not so the 360; it's an externally balanced engine, meaning the damper pulley and flywheel are deliberately unbalanced. (The motor balance is achieved via that plus balancing the crank internally.) So, you'll need 360 parts for that.

The oil pan is different, but if you get it with the 318, and it's a marine pan (cast AL) that will not be a problem.

Finally, the side mounts are slightly different. I'm told they can be modified, but be aware it's not drop in.

Jeff

PS: For a cruiser, the 360 has a TON more low end power than a 318.
Click to expand...

Jeff,
How much of a price difference in parts do you think im looking at, and basically what your saying is that if I just go with the basic 318 swap I should have no issues at all other than the occasional expected murphys law?
 
A 318 is a strong and reliable engine but as they say "there's no replacement for displacement".

If this helps, in the automotive world:

I believe the odd bank mount tab locations are different and just need to be shimmed fore or aft as required. Maybe one could just use hardened threaded rod with jam nuts and shims or flat washers.

A neutral balanced (steel crank) flywheel can be modified to work on an external balanced (cast rank) per Mopar. Mod dimensions are available if needed. You would need the 360 harmonic balancer.
 
Rendered Safe said:
Jeff,
How much of a price difference in parts do you think im looking at, and basically what your saying is that if I just go with the basic 318 swap I should have no issues at all other than the occasional expected murphys law?
Click to expand...
Eric, when was the last time that your heard of anyone complaining about too much power???
I'd go for the 360..... because your 26 foot SDN F/B can certainly use the additional torque.


daves69 said:
A neutral balanced (steel crank) flywheel can be modified to work on an external balanced (cast rank) per Mopar. Mod dimensions are available if needed. You would need the 360 harmonic balancer.
Click to expand...

Simple solution.... purchase the newly remanufactured 360 complete with flywheel and harmonic balancer.
Problem solved!


.
 
If you need, I have a 360 Aluminum Oil Pan I'd sell you for 100$ The 318 will not work. You can have your flywheel drilled to balance it to the 360. A competent machine shop familiar with Chryslers can do it for you. The motor mount can be installed using a couple washers to make up the difference in spacing, its pretty simple when you look at it. By all means go with the 360 over the 318, the added torque will be very welcome, for maximum performance you may need to change your prop, or have yours re pitched. The added HP of the 360 might allow it spin to many RPMs at WOT, but that just means you can get more top speed with a different prop, and lower RPM at cruise...
 
RicardoMarine said:
I'll preface this by saying that I'm not a Chrysler Marine Engine expert.... not by any stretch of the imagination.
Jeff and a few of the other guys will be able to offer far more help than what I'm able to.



.



Questions for Jeff and/or you other Chrysler guys:

What piston profile will typically be found in the Chrysler 360 Marine Engine version?
(I have a reason for asking!)

It depends there are both full dish (non quench) and partial dish (quench) Hypereutectic pistons available Keith black makes both, not sure about speed pro, stock they were usually flat tops, but so far down in the bore They would blueprint out to 7.5 to compression, that is why it is so easy to make big horsepower gains with a simple rebuild, just upping the compression to 9.5 to one with proper quench seemingly opens up 50 free horsepower, as to the rebuild, obviously the partial dish would be the ones to get if it is an option.

One rebuilder mentions "Hypereutectic" dish piston in their 360 Reverse RH Rotation engine specs.
We all know that "hypereutectic" refers to the aluminum alloy (high silicone content).... but what do they mean by "dished" piston?
Full Dish... or partial dish...... just exactly what can Eric expect?



Transmission and engine rotation:

Eric's boat is using a Reverse RH Rotation Engine "flywheel forward" installation, with a V drive transmission.
He has not yet posted pictures of the transmission.

What, if any, V-drives are "oposite of engine rotation" capable?
In other words.... what is the chance of his transmission being capable of using a Std LH Rotation Engine?
This may save him a few bucks!

Lastly... Ignition advance curve graph:

I know that we've gone round and round on this over the last few years.... and have kept coming up empty.

Has anyone to date been able to find the OEM Marine advance curve graph for the Chrysler Marine Engines??????
Not just BASE advance.... and certainly not the Automotive specs.
I'm curious!

I too would like to know, the original distributors on my motors were long gone, replaced by Mallory marine distributors somewhere in the past. I would like to go to the Mopar electronic ignition as I have always had good luck with the automobile versions in the many Mopars I've owned over the years the only ignition failure I've ever had is a bad ballast resistor, an easy 4$ repair, I even mounted a second one on the firewall of a couple of my off road trucks for security, but never needed them.

.
Click to expand...

Or you could go all out and put a 4" stroke crankshaft in a 360 block and end up with 400" of big block torque in a small block package (The geometry of the bottom end is excellent at 4" stroke, remember the roots of the A block Mopar go back to the Hemi's of the 50s, and the 392 had a 4" stroke stock.
 
Eric.... a brief shake-down, if I may.

I'm going to bet that your Chrysler engine is fitted with a Borg Warner bolt pattern flywheel cover (bellhousing in the automotive world).

It mates up to the rear engine flange just as the automotive bellhousing would.

The six bolt pattern is unique to Borg Warner and is industry standard, as well as the all steel drive coupler and the shaft splines are also Borg Warner..... also industry standard.

Whether your V-drive is brand X or Y, it also uses the Borg Warner bolt pattern.
 

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