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3.0L stock rods & bolts
Hello,
Because we are in the final stages of fine tuning my warmed 3.0L SC engine with 40 Webers, GE 60 cam and JE 95mm Pistons I fear the stock rod bolts on the stock rods might not hold to the estimated max 7,1-7,2k RPMs where we plan to set the rev limiter to. Would you think that the stock rod bolts will probably cause a problem here and we definitely should change them to ARPs? Thanks for your input, Christian Last edited by atelier14; 05-09-2010 at 05:05 AM.. |
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3.0 rods
For what you describe the stock rods will work well with ARP/race bolts, providing they are properly resized,magnafluxed,rebushed etc. and most importantly the rod bearing clearance is proper and not too tight. I would also recommend using the GT3RSR bearings instead of the street OEM or glyco bearings as the quality of the street bearings has not been very good for severe duty.
Mike Bruns JBRacing.com
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Thanks, Mike.
So you would recommend no to use stock rod bolts for my application? The long block is finished and actually in the car right now, so changing the rod bolts to ARP would induce lots of work here... |
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The stock rod bolts will work for the rpm range you have stated. However I would still upgrade as it is relatively cheap insurance.
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Aaron. ![]() Burnham Performance https://www.instagram.com/burnhamperformance/ |
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I think Mike & Aaron offer solid gold advice,.....
![]() ![]() Cheaper and more convenient to do this now rather than deal with any consequences from extended high RPM use.
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Steve Weiner Rennsport Systems Portland Oregon (503) 244-0990 porsche@rennsportsystems.com www.rennsportsystems.com |
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3 restos WIP = psycho
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Quote:
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a.k.a. G-man
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Quote:
9mm bolts are marginal in strength in the higher RPM range, the ones you have are stronger. It never hurts to upgrade to ARP though.
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Quote:
The person you spoke with at your dealer is quite mistaken,.... ![]() GT-3 rod bearings carry a 996 prefix and SC ones have a 930 one; they are totally different parts. These good bearings are not available through the aftermarket and are dealer items, only. Naturally, they come in Porsche boxes, not the red & black Glyco ones.
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Steve Weiner Rennsport Systems Portland Oregon (503) 244-0990 porsche@rennsportsystems.com www.rennsportsystems.com |
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Lots of good advice here, thank you!
So the GT3 rod bearings are available through Porsche dealers? Could anybody state the spare part #? |
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a.k.a. G-man
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according to PET 6
996 103 121 94 (for the GT3 2004 and onwards.)
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RSR brgs.
That is the part # for the RSR bearing, It is treated as a motorsport part in the US and the dealers can't get them. And PMNA sure won't sell them to you unless it is packed in your freshly rebuilt race engine
![]() Mike Bruns JBRacing.com
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RSR brgs
Kenik, the real problem with coatings on those bearings is the build up per shell can be .0004 in. and that reduces the already too tight oil clearances in most cases unless you coat,measure, and then have the crank ground to size.
Mike Bruns
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From the last few months of reading this forum, it would seem that the dealer supplied bearings go through a more rigorous selection/inspection process than the aftermarket bearings. Sounds like you are ok. (not GT-3 bearings though).
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Bill K. "I started out with nothin and I still got most of it left...." 83 911 SC Guards Red (now gone) And I sold a bunch of parts I hadn't installed yet. |
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Can this be right?
Pelican Parts - Product Information: 996-103-121-94-M100 Pelican sells them for $25/set. Doesn't sound right.
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Looked again. I did order the right part number:
996-103-121-94-M100 But they came in a red and white box. Odd.
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bearings
Its probably 25.00 per shell (or 50.00 per rod) that is the right part # post a pic when you recieve them
Mike Bruns
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Will do.
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Did you get them from the Dealer?
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No - a friend who has a local shop got them for me. I am getting the parts back in a few days...I'll look more closely when in hand.
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FWIW,..Dealer-sourced bearings are far preferable to aftermarket ones and thats all we use in these particular engines.
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Steve Weiner Rennsport Systems Portland Oregon (503) 244-0990 porsche@rennsportsystems.com www.rennsportsystems.com |
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