3.8 build longevity

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Oct 1, 2019 | 07:34 PM

#16

pwdrhound

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Quote:

Originally Posted by turboslut

Is there a reason you think that Porsche used the 997tt crank over the GT3 crank for what they had to assume was going to be a street driven car? Are some of those benefits of the GT3 crank negligible or actually detrimental in non race motors? Do you have the part number for the crank you are referring to?

I know...back from the dead, but just trying to do my hw this time around.

TT crank is likely cheaper to manufacture. The latest version of the RSR crank is the one used in the 991Cup. We installed this in my 4.0. Dimensionally it's the same as the old style RSR crank but has a mirror finish and all the bearing specs for each journal laser etched into the face of the crank. I have an extra used 997GT3 crank and a brand new 991Cup crank I'd be willing to sell if you are looking for one.

I will say that both my 3.8 and 4.0 engine using the RSR crank have absolutely none of the marble in a can sound that all the TT engines normally have. I attribute this to the better balanced RSR crank.