Anyone used '87-92 cylinderheads on older 360s?

[bikinkawboy]

I was reading some stuff on the internet (and we all know everything on the internet is true) and they talked about using '87-92 cylinder heads on older 360s. It appears the newer heads have the smaller valves (1.75" & 1.5") like the old 318 heads, but with the more effecient combustion chamber design, they will produce more power than the older 360 heads with their larger valves (1.8" & 1.6"). Supposedly they will swap without any modifications or changes and you can still use the older intake and exhaust manifolds.


I'm interested for a couple of reasons. The exhaust valves on my old 360 heads need to be replaced and while not unusable, there is play in the valve guides. Another plus is that the newer heads have hardened exhaust valve seats that should eliminate any possibility of valve seat recession from no-lead gasoline. Several years ago I had to replace the heads on the 318 industrial engine on my combine due to one valve on each head being terribly recessed. Funny that it was only one and on each head, with both being at the very end. I can't remember if it was at the same ends of the heads or at the same end of the intake manifold. So I figure that if I'm going to have to spend a chunk of money for valves and seat grinding on my old heads, I might as well invest in heads that produce more power and have hardened seats.

 

[bear]

Yes the 87/92 heads is a bolt on swap . You will have to block the smog ports that are under the exhaust ports though . What I do is tap them and thread in a plug into each cylinder .

 

[kork340]

Yep, the "308" heads are good from everything I've read. You can put the 1.88 valves in them. And like Bear says tap and put plugs in the smog holes. 1/4 in tap I believe and some allen head set screws. They are "swirl port" like the "302" casting heads for the 318.

 

[7mopar]

If you can put a automotive 318 cylinder head on your 318 industrial engine yes this is a swap that can happen. If I remember correctly there are differences in this two engines.

 

[bikinkawboy]

A biggest difference between the industrial version and the ordinary one is the crankshaft. The industrial versions use a forged crank as opposed to cast cranks. There may be differences in the flange end of the crank where the flywheel bolts onto. I'm not 100% sure if it was all of them, but I know that was true of at least one of the Chrysler industrial engines. I can't remember if it was the 225 slant 6, the 413 or what. I also believe the compression ratio was a bit lower. I would think the camshaft grind might also be different since the industrial versions normally run a maximum of 2200-2400 rpm. I also believe they used different materials in the crank and rod bearings.

I know the 318 was rated at 100 hp and the 225 on the other combine was rated 70 hp 100% duty cycle, meaning they were designed to produce that power under continous running. I know those power ratings are far less than the same engines were capable of producing in cars and trucks, but think of a dragster engine at the opposite end of the spectrum. Running alcohol, nitrous and supechargers, those engine are capable of producing probably 10 times what the street version of the engine would produce. But those engine are intended to produce that kind of power for very short periods of time, like to the end of the drag strip. On applications like irrigation pumps, the 318 industrial engine could produce 100 hp for 24 hours a day for 3-4 months at a time. Try running that drag engine continually at that kind of horsepower and catastrophic failure is guaranteed in a very short period of time.

The industrial engines I have use a single barrel carb and belt driven govenors in order to maintain a constant rpm.