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DustyR/T · **To stroke and cryo?**

A few people have heard my woes so far in this build up, but I have more questions for opinions. Even though I'm having my rods shot peened and the crank blueprinted etc etc, and forged .100 over pistons etc etc, I am considering investment in cryogenics for the entire short block. I got a price from a guy named rodney @ metal-wear.com based out of North Carolina for $400 package deal price for entire short block. I figure, why not? It's a method that has been proven through NHRA and Nascar regarding durability and strength. I am already spending around 2300 for the short block build, so why not another 400 for "cheap" insurance? When I do get my 3000+ saved for my turbo setup, not to mention cost for standalone, install, and tuning, I want to know in the back of my head that I can safely theoretically crank the boost to hold 500whp easily w/o worrying about something giving. Now I won't ever be running 500hp for practicality reasons, but it is a daily driver, and I want it to run as reliably as stock for at least another 100K. Only going to be using 5-7psi on the street, but after the tranny and is built up and axles are custom made, I might turn it up over double that boost to race it at the track.

Now on the topic of stroking, being a 6g72, rumor has it I can use a 6g74/6g75 crank? If I were to seriously consider stroking it, I don't want more than a small increase because long strokes and high RPM's do not mix too well under high hp.

Ntrain2k · 07-24-2006, 06:03 AM

For the money I would say go for it. Make sure you have all of your machining done ahead of time, and if you are going to have file fit rings make sure it is done before hand as well. Some processes actually make the metal a pain to do the work on afterwards.

I don't think the other cranks are a bolt in.

gkcooper · **That's a great price**

Will he extend that pricing to the TD community as well?

mwinkle353 · 07-24-2006, 10:30 AM

Now, Ron and a few others are going to flame me on this. But.........

Flatlander Racing, moreso ImportPerformanceParts.net actually sells a stroker kit for the 6G72. It makes the motor into a 3.3L. But there's been some speculation of the strength of the setup, due to the machining of the crank and forged pistons. However, with Cryogenics, you might be able to build yourself a decent Stroker for under $4k

Ntrain2k · 07-24-2006, 12:41 PM

No flame from here..

Offset grinding is one of the ways people have been making strokers from WAY back.

DustyR/T · 07-24-2006, 01:16 PM

Good, thanks for the input. I am waiting for the reponse back from my machinist to let me know how JE is makin out w/ my pistons.

Ondonti · 07-24-2006, 01:46 PM

I would not offset grind our crank with the bearing problems the motor has when it makes more then 200whp.

Ntrain2k · 07-24-2006, 02:12 PM

Quote:

Originally Posted by Ondonti

I would not offset grind our crank with the bearing problems the motor has when it makes more then 200whp.

Bearing problems?

Ondonti · 07-24-2006, 05:29 PM

#1 problem on 3000gt's is spun bearing.

DustyR/T · 07-24-2006, 06:14 PM

ok, so what is offset grinding?

mwinkle353 · 07-24-2006, 10:26 PM

Grinding the rod journals in a fashion that will effectively offset the centerline of the journal outward. Thus making it an increased stroke. You'll have to use smaller ID bearings for this type of setup.

DustyR/T · 07-25-2006, 02:30 AM

sounds like a cheap method to gain very little stroke while taking surface off the crank...not a route I'd be willing to take.

**c2xejk** · 07-25-2006, 11:31 AM

An alternative method is to find a shop that can weld up the journals, then offset grind them back to stock size... The increase in stroke is 2x the amount of the offset...

Note that offset grinding will require different length connecting rods...

mwinkle353 · 07-25-2006, 11:49 AM

Quote:

Originally Posted by c2xejk

Note that offset grinding will require different length connecting rods...

Or what Flatlander does..... They offset the piston pin height. So you can use stock rods.

mwinkle353 · 07-25-2006, 11:55 AM

Quote:

Originally Posted by DustyR/T

sounds like a cheap method to gain very little stroke while taking surface off the crank...not a route I'd be willing to take.

Just taking a little bit creates more than you think. Stock stroke on our motors is 2.992". The Flatlander kit uses a 3.242" stroke. Making the 2973cc stock motor to about 3310cc with .050" overbored pistons. Heck, with .030" overbore pistons, it's still 3280cc.

So, by offsetting the crank 1/8", you gain 1/4" of added stroke.