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Chrysler 318 and 360

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Hey Everyone!

I posted a few days ago about my dead 318 and I appreciate the help. If I put a Chrysler 360 in my boat, will that match up with my existing tranny?:confused:
 
The relationship between the Chrysler 318 and 360 is similar to that of the SBC 5.0L and 5.7L.
The two should interchange, and since you will be increasing horse power and torque, your existing ratio does not necessarily need to be changed.

There are some knowledgeable Chrysler guys here that can confirm this.
 
The 318 uses a different (internally balanced) flywheel and damper pulley than the 360 (which is externally balanced). If you want to interchange the two, be sure to use all 360 parts. The bell housing bolt pattern is the same.

Jeff
 
The intake of 318s and 360s are interchangable. The only real difference is in their flywheels, damper pulleys, and oil pans.

Jeff
 
....and the left (port, drivers side looking from the rear) motor mount. You can get an adapter
or use a couple nuts as spacers to move the 318 mount into position.

Jack
 
I went through this a while back. I have a 273 and want to get a new short block and was wondering if I can move up to a 318 or 360 using all the 273 accessories, like heads, intake etc. I was told on here, that a 318 was as far as I could go. I am not a Chrysler guy and a seemingly informed source wrote that a 360 had some differences that would make my 273 parts not fit. I really don't know but would like to know for sure. It is on this forum somewhere.

I was under the impression that it is not like a 305 vs a 350 Chevy where everything will bolt up but I don't know.
 
Will heads, intake, exhaust, etc from a 273 bolt up to a 360? What would be different, ie what do I have to make sure is included with the short block. I see flywheel, damper, and pan, anything else?


Sorry to hijack but I think this will help us both.

Thanks
 
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fastjeff said:
The intake of 318s and 360s are interchangable. The only real difference is in their flywheels, damper pulleys, and oil pans.

Jeff
Click to expand...
And head CC and port. Small port 273 & 318, Large port 340 & 360. Small port have 60CC chamber and large port heads have a 68 or 70 CC chamber.

The 360 uses a different oil pan that has larger end seals.
 
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pismo10 said:
Someone once told me (on this forum again someplace) that the marine 273 uses 360 heads? True?
Click to expand...

I think what you might have read is the 318/360 marine engines came with 273 heads but I have seen no evidence of that. 273, 318, 340 will interchange everything but as far as the 340
goes you wouldn't want anything from a 273/318 on it. The 360 has those few differences as mentioned but it would've been nice if they didn't bother..

Jack
 
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Main bearing diameters on the 360 are larger than 273, 318 , and 340. Hence the need for the change in oil pans. The balancing difference most likely due to the use of cast cranks in the 360 as opposed to forged steel in the older small blocks. All the cast crank parts would need to stay together as an assembly.
MoparSB.jpg
360 heads could bolt up to the 273 but the larger valves might require a notch in the block deck for clearance. Not worth the trouble.
360 heads and intake on a 318 should work with no mods except maybe plugging air holes next to the exhaust ports.
 
daves69 said:
Main bearing diameters on the 360 are larger than 273, 318 , and 340. Hence the need for the change in oil pans. The balancing difference most likely due to the use of cast cranks in the 360 as opposed to forged steel in the older small blocks. All the cast crank parts would need to stay together as an assembly.
View attachment 5545
360 heads could bolt up to the 273 but the larger valves might require a notch in the block deck for clearance. Not worth the trouble.
360 heads and intake on a 318 should work with no mods except maybe plugging air holes next to the exhaust ports.
Click to expand...

360 heads on a stock 318 give you about 7:1 compression.
 
Will heads, intake, exhaust, etc from a 273 bolt up to a 360?

Yes. Not sure about the intake ports, but the exhaust ports of the 273 are the same sie as those on my 360s. In fact, I use 273 gaskets 'cause automotive 360 gaskets are way too big and leak.

Jeff
 
daves69 said:
My info says only 4 cc difference on stock head volume. Do you have other info?
Click to expand...
​
Casting NumberEngine CIDYearIntakeExhaust
24653152731964-651.781.50
25320802731964-651.781.50
253617827319661.781.50
265823427319661.781.50
2658920273/3181966-671.781.50
2843675273/3181968-741.781.50
22683413181962-671.841.56
265823431819671.781.50
28436753181968-741.781.50
37699733181975-831.781.50
40271633181977-861.781.50
40275933181977-841.781.50
4323302318 Fast Burn1985-861.781.50
4323345318 Police1983-861.781.50
25318943401968-702.021.60
3418915340TA19702.021.60
34189153401971-721.881.60
367158734019731.881.60
34189153601970-721.881.60
36715873601973-741.881.60
37699743601975-761.881.60
367158736019761.881.60
40275693601977-861.881.60
Table 1. Chrysler Small Block Cylinder Head Volumes (cc)​

Casting NumberYearChamberExhaust
Port		Intake
Port
2465315 / 26589201965-196664.560127
34189151971-19727169149
40275961980-19847165149
43233451985 -->7462150
43233021985 -->6254118
 
Damn, that's beautiful!

Where did you come up with all that? I'm very impressed. (It's a Keeper.)

The two heads for 1985 up are interesting. Note that one of them (4323302) 'appears' to be a truck/ marine head with maller ports for better torque, though it has less chamber volume for higher compression.

Jeff
 
Jeff, I just looked at the different Chrysler 318/360 combustion chamber volumes. I see anywhere from 62cc to 74cc.

Question: would swapping cylinder head castings not be similar to that of the SBC cylinder head chamber volumes, in that we'd best be careful when arbitrarily changing chamber volumes, without also a change to the piston profile?

I hate to make this comparison, but I'm not into the Chryslers like some of you guys are.

But with regard to the SBC Marine version, if we take a SBC set up for the 64cc chambers (typically fit with the full dished piston), and install 76cc chambers (typically fit with F/T's), our SC/R suffers.
Likewise in reverse, if we take a SBC set up for the 76cc chambers, and install 64cc chambers, our SC/R is increased beyond what most will tolerate without serious detonation concerns.

IOW, if you were to make a change to the chamber volume, would you not also make a change to piston profile as well?

Just curious!




.
 
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