12v cummins towing modifications

Why would you preset a small turbo for 45psi? Your gonna kill it and pop a head gasket while your at it.
 
Serioulsy. We are supposed to be a higher end discussion forum and still spreading nonsense like weak shafts and boost is a concern with head gaskets.
 
Excessive drive pressure from a turbo that is way off its map causes no concerns for a HG? Sure wouldnt be where i would be putting my bets in a rig that is gonna be worked hard.
 
turbo2387 said:
Excessive drive pressure from a turbo that is way off its map causes no concerns for a HG? Sure wouldnt be where i would be putting my bets in a rig that is gonna be worked hard.
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So, 100psi in a exhaust manifold is harder on the head gasket than exploding a finely atomized mixture of diesel fuel in a cylinder full of 400psi compressed air that proceeds to explode subjecting the head gasket to thousands of PSI?


High drive pressure doesn't kill a gasket by itself...bad tuning blows gaskets.

High drive just reduces efficiency...couple that with pushing a charger off it's MAP, and that's why shafts break. I made 638RWHP with a HE551V at 36psi boost, drive would run about 45psi when I checked it. Boost isn't needed if you can move the air.

That same 95 truck I talked about earlier literally had 40+ different turbo setups on it...including a couple of twin sets, one even being a small set that made 86psi boost at god knows what drive...all on the stock head gasket and bolts at 285K-385K miles. The timing was always pretty conservative at 16-17* so that's what I always attributed the head not coming off to.

IMHO,
Chris
 
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Racinboy18g said:
So I ended up going with a 60/65/12 turbo with 360 bearing and billet wheel and he machining the 4 3/8 flange on it for me for my fummins conversion since DCS has a pipe already for them. It has the bigger shaft in it not the 7mm one. Adjustable waste gate preset at 45 pounds. And I got 5x12 injectors for it. I think it should spool pretty good and have enough up to.
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Back that wastegate down under 40psi and I'll bet it cools off some. I always ran about 38psi, worked well for me.

Chris
 
turbo2387 said:
Excessive drive pressure from a turbo that is way off its map causes no concerns for a HG? Sure wouldnt be where i would be putting my bets in a rig that is gonna be worked hard.
Click to expand...

Yea. All the drive pressure. :nail:
 

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Is it true that the injector guide slots in the head do dual duty as boost relief paths, so as to avoid head gasket issues?
 
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