Do you know????
- Thread starter Wifey
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318 wide block
Maybe for an Industrial application, in this case.
At least 6 feet from one valve cover to the other.
Maybe for an Industrial application, in this case.
At least 6 feet from one valve cover to the other.
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Cylinders/ Heads?
Yup...I looks like it has both!
Flat Exhaust manifolds and maybe (?) some kind of limiter on the distributor.
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I really don't know all that much about these but they are a predecessor to the 318 LA engine I thought it was interesting
What Is A Mopar 318 Polysphere And How Come Nobody Likes It?
Over time, there are some engines that came and went, and never really caught on. The Mopar 318 is one of them.
www.streetmusclemag.com
Both the modern 5.7 and 318 wide block use a semi-hemi design that works well and has benefits of true hemi and wedge designs; such as airflow and squish/Quench. The last one in particular is lacking in the true hemi design and can be prone to detonation without it.I really don't know all that much about these but they are a predecessor to the 318 LA engine I thought it was interesting
What Is A Mopar 318 Polysphere And How Come Nobody Likes It?
Over time, there are some engines that came and went, and never really caught on. The Mopar 318 is one of them.
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The last one being wedge?
I knew you and some others on here would be familiar with this polyspheric design - not sure why I wasn't but I learn something every day. I came aross it on an auction site featuring an early 60s W100 truck and had to figure out what a poly engine was
No, sorry, the true hemi head doesn't have Squish/Quench.
That's when part of the outer area of the piston crown comes very close to the cylinder head surface (squish). That serves to both compress the fuel and air (making it easier to burn) and also creates high-speed air to cool the far side of the combustion chamber to prevent end-gases from igniting PRIOR to the plug firing, which can cause pre-ignition.
So..Squish is the actual event and Quench is the result.
You may have heard the engine term "Zero-Decked"? Well, that is when Squish/Quench has been taken into account during an engine build.
Poly chambers can benefit from this and true Hemi chambers can't.
My motorcycle engine uses a poly chamber, so they aren't exclusive to Mopars.
That's when part of the outer area of the piston crown comes very close to the cylinder head surface (squish). That serves to both compress the fuel and air (making it easier to burn) and also creates high-speed air to cool the far side of the combustion chamber to prevent end-gases from igniting PRIOR to the plug firing, which can cause pre-ignition.
So..Squish is the actual event and Quench is the result.
You may have heard the engine term "Zero-Decked"? Well, that is when Squish/Quench has been taken into account during an engine build.
Poly chambers can benefit from this and true Hemi chambers can't.
My motorcycle engine uses a poly chamber, so they aren't exclusive to Mopars.
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Poly 318A aka semi-hemi, in use through 1966. Precursor to the 318LA.
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That's what the pic I posted is. I think lol
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Ding ding ding
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Thank you!!
I was going to say the 273 cid , which had mechanical cam and adjustable rocker arms was pre 318 cid … no idea what the thing on the distributor is as Ronnie noticed …
273 was the first LA engine (LA = 'Light A') but doesn't predate the A engine; that goes back to the 50's. Yes it predates the LA 318. Every Make had one as the lower tier engine to the hemi except for Plymouth. 50's Plymouth never got a hemi, only Chrysler, Dodge & DeSoto did and none of the parts were interchangeable between makes.
Yep. The scalloping on those valve covers is very distinctive.
Built in ignition module. Think the old Mopar ignition box but integrated into the housing.
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And I thought the 318LA was the California version. Half the power, Half the economy Hahaha
Yet the smog would burn your eyeballs out like cutting onions back then 120 miles out. So much for climate change of course back then they call it air pollution . California was the leading state of you’re gonna die at young age from small inhalation, ha ha, ha, ha, ha.
