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Do I Rebore And Rebuild Block Or Throw Away And Try Again.

Quigs

By Quigs,
in General Automotive Discussion

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Quigs Contributor

Quigs

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I know it's no skyline guys but I was Just pulling down the ca18det in my 1200 coupe to replace the head gasket the afternoon and I found some pretty nasty scoring, scratching and no 4 cylinder bore feels wavy and out of round. The plan was to clean the head up and put it all back together but I've been told by 2 separate mechanics to not even bother and find another block. I feel very defeated at the moment as I was planning to get the car back on the circuit by June 1 to compete in a super sprint at SMSP. Note what appears to burn marks on the head gasket and cracks where water has leaked into oil gallery and on no 4 cylinder bore it looks as though there are also burnt stain marks? post-97175-13937692996135_thumb.jpgNo 1 piston has a massive score mark in it and no 2 and 3 seem to have a lot of scratches. Is it worthy to get it rebored say to 20 thou oversize fit new pistons and rods or just find another block? For a proper rebuild the parts list alone is about $3000 and I bought the track car for $5500! Or maybe just buy a used engine bolt it in and get it back out on the track. I've owned the car 2 1/2 years and I still feel like I'm getting used to driving it with only about half a dozen events completed. :( very frustrating. Thank god the 32 R in the shed isn't the track weapon and just the weekend toy. Rant over

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Trex Grand Master

Trex

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I'm not an expert but if it's possible to save the block id do that and rebuild it with new pistons and a gasket kit and put it back together. The engine shop should be able to tell you if the rods are fine when they're connecting them to the pistons. Or another way, buy a block get it honed and put all your shit into it? Would probably work out the same price though.

It's kind of redundant to buy a second hand engine, heaps of stories about how it's a fresh engine with 60,000ks and never been boosted, only to find it's dropped a cylinder.

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Quigs Contributor

Quigs

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Yeah I wasn't sure if I should reuse the standard rods but I suppose if they're still in good condition it's probably a good idea save some $$$ and even on a race track I try to avoid revving past 7000 rpm as the engine isn't making any more power past 6800. Probably far cheaper in the long run to just rebuild it properly now and at least I know where I stand. Thanks for the suggestion

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Shoota_77 Veteran

Shoota_77

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CA's are so cheap so I'd just find another one, bolt it in and off you go. You'll pick one up for a few hundred maximum. Lots of blokes here running standard bottom ends in race cars with no issues.

Personally I'd rebuild it but if time is an object bolt the new cheap donk in and fix up the existing engine while the car is still on the track.

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