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...Ok, Im somewhat of a new-school old-schooler...I like EFI over carbs, but I prefer push-rods to overhead cams...So, I dont know a whole lot about the inner workings of OHC engines...
...Are our 2.3s "interference" engines (I know what that means; just dont know how to tell)?? ...Are all OHC engines interference, or just some, or what??
Thank you!!

 

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...Ok, Im somewhat of a new-school old-schooler...I like EFI over carbs, but I prefer push-rods to overhead cams...So, I dont know a whole lot about the inner workings of OHC engines...
...Are our 2.3s "interference" engines (I know what that means; just dont know how to tell)?? ...Are all OHC engines interference, or just some, or what??
Thank you!!

Some are interference, some are non interference. The zetec was non interference, the PZEV also is I'd assume, but I dont know.

In and interference engine the valve and piston could be in the same spot in the cylinder at different times. If a timing belt or chain were to let go one one of those engines it causes collisions which break parts of the overhead of the engine.

The noninterference egine is designed so that the piston and valve will never overlap that same space. So if your timing belt goes, things wont go right straight to hell.

Overhead engines are both easier to work on in my opinion, and easier to tune. Having a seperate cam for the intake and exhaust is a great thing.
When you have no displacement, you need something to get you power
 

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the Duratec I4s are interference engines.

be very careful when adjusting Cam timing.
 

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the Duratec I4s are interference engines.

be very careful when adjusting Cam timing.
Hence the timing chain then I guess. Cam timing will suck with this engine anyway, since most dont own a dyno, I dont know that it'll be done as commonly as with the zetec.
 

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On a similar note...

I assume the cam gears are probably keyed on this engine?
If they are I'd be much more likely to do cam gears.
However, in the picture below I see no indexing pins.
 

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I hope it is... Nothing wrong with an omni
I've been spanked by many GLH's in my day.
 

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look earlier in the post...basically if the timing chain/belt falls apart, in a noninterference engine, no parts'll hit. SO the engine will prolly be undamaged. IN an interference engine, stuff hits, so you end up with valves bent against pistons, pistons with gashes in them, bent pushrods (if you ahve them) etc, etc, etc. Basically in a non-interference engine most parts in the rotating assemblies can be damaged if parts go out of sync for whatever reason
 
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