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aviatorg3 06-18-2010 06:02 PM

Reverse Rotation Engine
 
I have a question regarding Reverse Rotation engines. If the engine is turning the opposite way, does that affect the oil pump and or plumbing as opposed to a standard rotating engine? Any help would be greatly appreciated.

Rookie 06-18-2010 06:34 PM

Instead of a timing chain, the cam and crank are ran gear to gear. And on the engine that I did the sea pump the IN was the OUT. (switched)

picklenjim 06-18-2010 07:06 PM


Originally Posted by aviatorg3 (Post 3139609)
I have a question regarding Reverse Rotation engines. If the engine is turning the opposite way, does that affect the oil pump and or plumbing as opposed to a standard rotating engine? Any help would be greatly appreciated.

No affect on the oil pump. Camshaft turns the same direction in both engines. Therefore the distributor which drives the oil pump also turns the same direction. Firing order is reversed via plug wire location on the cap.

ezstriper 06-21-2010 06:12 AM

thats not true anymore as on big blocks they do not reverse them that way...they run a special cam with a reverse cut dist gears and only turn the dist the correct way to run the oil pump, retaining the factory timing chain setup..requires a special dist....not sure if its a better way that the old gear ti gear setup....ran into all this when repowered my gibson a few years back...

justdreamin 08-05-2010 10:29 AM

I am also confused.... I bought a reverse rotation engine and was told it was a standard rotation. I want to change it to standard...(asap) Here are my question areas...

New Distributor? (Was told there was spiral cuts on the distributor bushings that helped oil flow up during rotation and if I did not change it... it would push oil out and wear out..
And I am aware the gear on the bottom would be wrong.

Cam Shaft? Obviously need a standard rotation right? (and might as well put new lifters in)

Is the crank the same?

It had an alternator on it too if I ran it as a standard rotation wouldn't that excite the alternator?

I also read that the crank seals are different on reverse rotation.. Has to do with deflecting oil..

As well as (Don't laugh) the manufacturer's put the piston's in upside down... and what i mean by that is there is a mark on the piston when you are sliding them in on whats 12 o'clock and in a reverse rotation they put it in at 6 oclock

Am I missing anything. Can somebody verify. Cam, Lifters, Alternator, Distributor, Crank Seals, Pistons in upside down

justdreamin 08-05-2010 10:44 AM

Guess I should of read this first
http://www.offshoreonly.com/forums/g...-question.html

RunninHotRacing163.1 08-05-2010 10:56 AM


Originally Posted by ezstriper (Post 3140890)
thats not true anymore as on big blocks they do not reverse them that way...they run a special cam with a reverse cut dist gears and only turn the dist the correct way to run the oil pump, retaining the factory timing chain setup..requires a special dist....not sure if its a better way that the old gear ti gear setup....ran into all this when repowered my gibson a few years back...

Xactly :drink::drink:

SHAWN DAVIS 08-05-2010 12:12 PM

Cam, distributor if using mechanical advance, crank seals.
alternator will charge in both directions in most applications.
reverse the firing order on the cap from standard direction.

If running a blower you have to drive it off the opposite rotor also.

mcollinstn 08-06-2010 05:50 PM

Technically, the "correct" way to orient the pistons on a reverse rotation motor is "backwards". This is because the wrist pin is slightly offset to deliver a more favorable rod angle on the power stroke. Rotating backwards changes the force vector to the opposite side of the combustion chamber. Some do, some don't.


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