OPG + Sprocket

Planning on upgrading OPG & Sprocket soon. Don't mean to sound silly but do these gears require a break in period?

No

They don't, but you probably should look up what's required to prime an oiling system with a gerotor oil pump and plan accordingly.

@Catmonkey did you use the oil pressure sensor port and pressurize the system via an electric oil pump?

Double post.

I have a Shelby oil pressure manifold adapter and used one of those unused port and it is plumbed into the original sensor location on the oil cooler/filter adapter. I used a pressurized canister that injects oil via air pressure. On initial start up I held the accelerator pedal to the floor which won't allow the engine to fire until I saw pressure on my gauge. I do the same thing when I change my oil. The starter spins the engine about 300 rpm, which is better than the 1,000+ rpm on cold start. I just plumbed a cheap oil pressure gauge into the adapter on initial start, so I could monitor oil pressure both during the injection process and the initial start of the engine. Watch those headers. LOL!

The Chevy LS engine has a gerotor pump that runs off the crank, just like the mod motor. There's no shortage of YouTube videos on various methods to get this done. Not priming it could be tough on the cam tower journals.

Thats way overkill.

Better overkilll than killed.

Thanks Fellas !

I know thees are highly recommended on the coyote motors but are they really necessary on the GT500's?

Marty Staggs said:

I know thees are highly recommended on the coyote motors but are they really necessary on the GT500's?

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With the wick turned up and running higher rpm, that weak link starts to surface, but if it's a weaker link than the rods, I'm not sure. It's certainly easier and cheaper to install these than a set of forged rods. If the gears shatter, the engine is done and these are not cheap engines to rebuild. Anyone that builds their engine goes that route, but I haven't seen that many install them in otherwise stock engines. I'm sure it can't hurt anything. BiminiLX comes to mind on breaking the OEM set in his 5.8. Realize the 5.4/5.8 has a .5" more stroke than a coyote too, so crank vibrations will come in at lower rpm than the shorter stroke.

I'm planning this OPG/Sprocket mod mostly because on spirited weekends I find myself in situations rolling with another car between 15-40mph . In these instances the pedal gets slammed down. MT's are set low around 20psi and they dead hook. Like many guys I also powershift . I have the stock crank pulley ...not aftermarket...but still I'm told these sudden drivetrain impacts can shock or create vibration of the OPG. I'm usually pulling the stick as it's crossing 6,000-6,200 rpms but at times it might be higher. I was of the understanding higher rpm's or sustained high rpm's is where rods may be more under stress.
Am I mistaken on these assumptions ?

I've always understood OGP failures to have to do with unbalanced harmonics at higher rpms. The gears are only driving oil, so I'm not sure they would have that much stress on the initial hit, but that's only speculation on my part. I could see something like a two step or hard rev limiter where you have no and full power in rapid succession beating them up. If you had a big supercharger up top, perhaps you could have snout flex that could put the OPGs in a bind on the initial hit that might lead to that conclusion. It's cheap insurance on a build, but would be a real PITA to go in and just do it. Beside J's failure, who else has had OPGs go south?

Catmonkey said:

Beside J's failure, who else has had OPGs go south?

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Good question Catmonkey.....OPG on a build is a no brainer. Maybe I should've started the thread asking who has done OPG's on stock block motors with just FBO's and why.
My shop suggested I consider the upgrade " if you drive the car hard". I imagine " hard" can mean lotsa things. I know the TT Mustang guys do that mod once they start making big power.

Okay...I called Ford Racing Tech line. The words used on the cause of an OPG beakage was
"uncontrolled torsional vibration" where under certain extreme conditions the crankshaft vibrates beyond the tight clearances or tolerances effecting the OPG or sprocket.
The tech could not specify in accordance to HP as the cause but power mods, pulley changes & hard driving can both contribute to the vibrational surge. What I was told was it could be good insurance with cars used for drag racing or even low roll racing where a launch or stab sends the sudden vibration. SOOooo...still has me spinning ->) ...but perhaps it's a good thing to consider this season.