Cylinder Wall Nick, Reccomendations Please
#16
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Drifting
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From: Bangkok, Thailand, Milpitas, CA & Weeki Wachee, FL
I might be leaning that way now. I sent the pictures to 928 Motorsports as they seem to specialize in reconditioning Alusil and Nikasil blocks. Instead of telling me they could fix it and thus generate income for themselves, they reccomended that I touch it up a bit and assemble the engine. This was very surprising to me!
#18
I can help you find a clean 2.5 block - would an NA block work for you? There is a local dismantler that specializes in 944s, and they have a lot of clean NA blocks. Turbo blocks, not so much. I got a perfect NA block for 250 or something, I forget the exact amount.
#19
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#20
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Drifting
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From: Bangkok, Thailand, Milpitas, CA & Weeki Wachee, FL
You hit the nail on the head with that statement!!! I am far too ****, and that is the major problem. However, I have a friend down in St. Petersburg that owns a Racing Engine shop. He is an old timer and has been in business since 1970 in the same location! Every short track and sprint car racer in the area uses his services. I am loading everything in the truck today and taking down to him for inspection. He wants to measure everything and determine where the piston is located in relationship to the valve train opening and closing. If he tells me I am good to go, then I am going to let it ride. I took a few more pictures yesterday with the top ring installed, that make it look a little better than first anticipated. I might also swing by Frank Eibell's shop to see what he thinks. He is another old time Porsche specialist in St. Petersburg since 1976.
#21
..While I'm sure this is not the answer you want to hear. I've seen motors with much worse run perfectly for a very long time with no ill efects. Depending on the texture of the edge, you could break a ring on the ridge but the performance loss I suspect will be minimal. Chat with Chris White and see what he thinks. Personally, I'd be pretty pissed off over it and would roll the dice.
I have a bigger gouge in the #4 cylinder of one of my 944 spec race motors. I took some fine sand paper and knocked down any ridges. Then I put it back together and raced it for 80+ races. No oil burn, no noticalbe power loss. Right now the motor is out of the car for some head work due to some leaky valves caused be years of build up. The block is still fine. So I suggest using it as is.
This picture was taken when I took the motor apart this this past winter. I was 6 years and 80-90 races since I put it back in with this scratch. Car made solid power as compared to all other 944 spec cars except when an intake and exhaust valve on cyl 2 & 3 got dirty and started leaking.
#22
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Drifting
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From: Bangkok, Thailand, Milpitas, CA & Weeki Wachee, FL
Joe:
Thanks! Definitely looks worse than mine, so maybe I will be fine. Still heading down for further advice at the aforementioned shops. I will post the findings later.
Thanks! Definitely looks worse than mine, so maybe I will be fine. Still heading down for further advice at the aforementioned shops. I will post the findings later.
#23
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Drifting
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From: Bangkok, Thailand, Milpitas, CA & Weeki Wachee, FL
I made a small Excel spreadsheet for piston location. I have no idea if anybody would have a need for this information, but just in case I will attach it. You would just have to switch in your piston and cam information.
Last edited by URG8RB8; 08-27-2009 at 11:45 AM. Reason: Zipped attachment
#24
Move on already.
#25
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Drifting
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From: Bangkok, Thailand, Milpitas, CA & Weeki Wachee, FL
Well, after visting with the two shops down in Saint Petersburg I received the "go ahead" from both places. Frank Eibell of Eibell Performance reccomended the same proceedure as Ski previously mentioned for all four cylinders prior to reassembly with new pistons and rings. I took this advice and had all four cylinders felt honed with the Sunnen AN-30 Silicon slurry paste. The cylinders look much better now even though this process had no effect on the "ding". I will post some pictures below after the process and cleaning up with mineral spirits and later hot soapy water. I think all will agree that the cylinders look much much better now!