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Copied from another post, a must read!

1206 Views 4 Replies 4 Participants Last post by  lo bux racer
"Some on here need to do themselves a favor and read Corky Bell's book, "Maximum Boost".

It explains all about torque load increases on drivetrains, engine enternals, etc.

Basically a doubling of power from being boosted only increases the actual load at the critical position of the rod/piston/crank by 20%, which when properly tuned relates to around a 10% reduction in life expectancy of a properly tuned engine.

I forget the approximate numbers for the drivetrain but they are not that much higher than stock either, we have not heard of a broken gear box yet on a boosted tC, that I know of at least.

Broken axles, yes, drag slicks envolved, they are the real culprit here.

Most things that break are due to neglect, negligence, i.e. impoper tune, just plain bad driving.

One more point, I have already found used engines for $1k or less, taking my time 2 days to swap, working a long fast day, one day swap.

Rick "
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Reply from another post:

It's not the engine that's the weak link. Toyota does not build strong transmissions. They never have. Stout engines, weak transmissions. Been that way for years.

You don't hear about broken gearboxes until they start shifting badly. Someone pulls one apart and all the bearings are shot. Just like clutches, gearboxes are rated by torque. NOT horsepower. All the turbo kits dramatically increase torque from the engine. The supercharger does not increase peak torque much at all. I'm dead certain there is a reason for this, and I'll bet the E350 starts burning up bearings in relatively short order.

Keep in mind, a gearbox is typically designed for a 250k mile (minimum) service life. If it dies in less time, it is being stressed beyond the design tolerance. And gearboxes fail because their bearings fail. Not because the gears have problems, but because the bearings won't live to full service life. As soon as the bearings start to go, the gears chew themselves up in short order. It's all about bearing life...
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Is this mildly in response to what I said about the turbo tC and closed loop and torque spike and break and bad things and stuff?

I was alluding to (or.. I think I may even have just said) that it'd be a result of a lack of tuning in closed loop and running 30 psi on the 2AZ. For one I bet the ringlands would crack and two I bet something else will break too. With a 100% increase being a 20% increase in stress, we'd be looking at almost 200% increase due to 30 psi boost, so almost 40% increase in stress.. I dunno.. I don't know much and the 2AZ IS pretty sturdy so perhaps we won't see critical failures?

Anyways, thanks for the correction. When I get some time I'll read the book. Just one question though, is it as interesting as The Chronicles of Narnia?


Sorry for the constant questioning.. but how's the progress on the suspension problems? I don't even know what to ask specifically because last you said something about it my head was spinning from all the new and completely unintuitive ideas.

BTW, I hate when I call people by their first names and have them not know mine.. Rick, Lance, call me Kevin
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That's interesting. so the S/C does not were out engine life at all? i need to read that book, thanks for the information.
No. The SC was designed with service life of all the car's components in mind, and with a minimum compromise of that service life.
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