FW Motorsports
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Car Info: 07 rs STi swapped Rotated BW S200SX-56
I could blow up a darton sleeved block under the right or I guess wrong circumstances too. Just was saying that for the average person, forged pistons would make a fairly robust endine. Don't you have a drum in your shop full of failed cast pistons, lol.
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Forged pistons from the factory would be awesome but I think the reason they don't do it is the poor cold start emissions you get from them. I doubt they would be able to pass CARB standards with a good forged piston. Once the engine is warmed up and the piston has expanded, emissions are fine, but on cold start the piston to wall clearance can be pretty big causing blowby. At least that has always been my theory on why they used cast pistons in almost all modern production engines.
Thanks
-- Ed
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From: 2006 Zero/sports Widebody
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2nd photo looks like pre ignition. To me anyways it looks melted. And again not a whole lot of damage going on besides the piston.
They both look really clean. As in steam cleaned.. water was in there? I'd be worried on the 1st one at least of a micro crack in the cylinder wall.
What do the heads look like?
Last edited by old.guy; Dec 24, 2011 at 10:58 AM.
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Car Info: 2005 LGT wagon
Thanks. The guys work hard at keeping it that way.
BTW, both cars have unknown pasts, as both current owners have only owned their cars for a few months.
As received, both car's live data & learned values showed any thing out of the normal.
The 06 STi's owner reported that he got on it & then heard/felt "something" & then a ticking sound. We confirmed the ticking sound...loose valve lash sound...by pulling the valve cover & doing basic mechanical diagnostics. Sure enough, one exhaust valve had 4 times the normal clearance.
Recommended pulling the engine & removing the heads and the customer agreed.
He'll be leaving with a fully built forged internals engine with a ~1 week turn around time.
BTW, both cars have unknown pasts, as both current owners have only owned their cars for a few months.
As received, both car's live data & learned values showed any thing out of the normal.
The 06 STi's owner reported that he got on it & then heard/felt "something" & then a ticking sound. We confirmed the ticking sound...loose valve lash sound...by pulling the valve cover & doing basic mechanical diagnostics. Sure enough, one exhaust valve had 4 times the normal clearance.
Recommended pulling the engine & removing the heads and the customer agreed.
He'll be leaving with a fully built forged internals engine with a ~1 week turn around time.
Last edited by FW Motorsports; Dec 25, 2011 at 08:10 PM.
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Car Info: 2005 LGT wagon
