When should one perform OPGs/CS?

Kiohtee

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Important note: Car in question is a 2017 GT 6R80

I'm getting a lot of mixed answers, so here goes:

Phase one of my car was what is considered full bolt-on (full Cobra Jet setup and full exhaust). Turned the car to 7800 regularly on stock OPGs/CS. Never had a problem. 93 pump.

Phase two of my car was the same minus the Cobra Jet setup. I returned to my stock IM and a PMAS CAI, kept the exhaust and started spraying a 150 shot with a BAP. No motor problems, but nitrous activation was spotty and leads to...

Phase three. My car is currently being torn apart for a twin turbo install. Counting on some 1200 injectors, my current BAP and E85 to make 800RWHP. Not many, if any, are recommending the OPGs/CS even at this point in time, because supposedly being an automatic and turbo car, plus not making a ton of power, should buy it some time.

What says ye SVTP?
 

tones_RS3

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From reading over at the other Mustang forum, it's a good idea to install the OPG's and crank sprocket gear when boosting. Just a safe guard if you will.
Especially if you rev the engine to the moon and back. lol
 

PC03GT

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OPGS are like a condom, if you want to play with fire, you might get burnt
 

NightRide

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Most say revving high or big whp to do them. Since your doing both i vote yes. I keep my rev limiter at 7k and make 650whp on the stock motor fwiw. If I turn up the limiter or push above 700 whp I'll look into doing it.
 

Kiohtee

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I get the general consensus that I should do them, and that's fine, but trust me, I'm not revving high. Car is a stock IM car with twins.
 

DMassey

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you can ask 100 people and get a dozen different answers.

Personally, I've seen 2 major contributors:
1. harmonics from super high rpm & hitting rev limiters/2-steps
2. side load from supercharger pulleys, particularly the add-on pulley like ProCharger uses.

Turbo cars don't have that side load on the crank snout. Having said that, if I'm building something 700+ hp, I'm throwing some billet opg's in there. It's cheap insurance vs. a whole new motor.

Also of note regarding high-rpm harmonics... it seems that the Gen2+ motors have better high rpm harmonics than the Gen1 motors.
 

Kiohtee

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you can ask 100 people and get a dozen different answers.

Personally, I've seen 2 major contributors:
1. harmonics from super high rpm & hitting rev limiters/2-steps
2. side load from supercharger pulleys, particularly the add-on pulley like ProCharger uses.

Turbo cars don't have that side load on the crank snout. Having said that, if I'm building something 700+ hp, I'm throwing some billet opg's in there. It's cheap insurance vs. a whole new motor.

Also of note regarding high-rpm harmonics... it seems that the Gen2+ motors have better high rpm harmonics than the Gen1 motors.

You hit on my main points/thoughts exactly Derrick! The harmonics from high RPM, hitting the rev limiter and added stress of a two step don't exist in my car; because 7,000RPM max, automatic transmission and no two step. The added pulley load also doesn't apply since I have a twin turbo car, so that stress is eliminated too.

I'm just curious if I can spare another $2K (which pales in comparison to the $8-10K a new motor will cost) and still maintain longevity. Being an automatic twin turbo car, the car is naturally easier on the parts versus a PD car with stick.
 

SheepDog

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Why not just do it and sleep easy at night? A few hundred dollars to protect your 20k build seems like a no brainer to me.
 

Kiohtee

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Why not just do it and sleep easy at night? A few hundred dollars to protect your 20k build seems like a no brainer to me.

It's not a few hundred dollars though. It's actually almost $2K. I realize this is the one thing my mechanic is high on, but he doesn't like doing them and he's a one man show (that is scheduled to the max). Taking it elsewhere just isn't an option at the moment, and even if I could I don't know that I would. My loyalty lays with him.

Thanks for all the feedback nonetheless fellas!
 

SheepDog

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The boundary set is $298 from most places, so he must be charging you a shitton for labor. Too bad you don't live closer to me, I would do it for 500. It really isn't that difficult, just a bit time consuming. Simple hand tools is all you need and a space to work and you could do it yourself. It would take a while longer though once all the Turbo components are in the way.
 

PC03GT

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It's not a few hundred dollars though. It's actually almost $2K. I realize this is the one thing my mechanic is high on, but he doesn't like doing them and he's a one man show (that is scheduled to the max). Taking it elsewhere just isn't an option at the moment, and even if I could I don't know that I would. My loyalty lays with him.

Thanks for all the feedback nonetheless fellas!
Damn, got mine done for 800, that was after the blower was on
 

SheepDog

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Oh one other thing I forgot to mention and maybe you are already aware of this- pushing 800 HP on E85 with only a BAP is very risky business. At a bare minimum I would recommend replacing the in-tank pump with a DW400 and using the BAP, or the much better option of running a return system. I would hate to see you grenade your beautiful new build. Just my .02
 

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