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Wo ist die Rennstrecke?
Join Date: Mar 2004
Location: St Johns, FL
Posts: 1,210
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It's alive - again
After downloading the latest firmware upgrade from Electromotive in June, my newly rebuilt 79 930 promptly split 3 cylinders and shattered all 6 of the top rings due to detonation (enrichment settings moved somehow, but Electromotive said it never happened during their beta tests). All 6 JE pistons (8.0:1 CR) were in perfect shape.
So, faced with another rebuild, I had new cylinders made at JB Racing in FL - they look like jewelry. They are also 98mm with fire ring grooves cut. The previous cylinders were bored stock cylinders from EBS. The new cylinders are iron with billet AL fins and fit like a glove (case and pistons). I also opted for chrome moly rings rather than the cast rings used on nikasil cylinders. While apart, I also had the heads port matched and opened to match a 3.2L head (I have a 3.2L intake). I spent the last three days assembling the motor and started it yesterday. After fixing some of the enrichment settings that the firmware moved, I took it for a drive today. I reset the cam timing to 1.9mm, down from 2.3mm. The reason I did this is because the motor would stop making power at 6200 rpm (the cams are super C2 grinds from Elgin). Its too early to tell if there is a difference in low-end response yet. Before the re-rebuild, I got 500 rwhp. After I get a couple hundred miles on the clock, I'll dyno again for top-end tuning and power. |
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Registered
Join Date: Jan 2003
Location: Langley,B.C.
Posts: 12,002
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Wow, cracked cylinders, that sucks! 500HP, yikes! Is the new motor essentially the same besides the cylinders?
Jeff
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Turn3 Autosport- Full Service and Race Prep www.turn3autosport.com 997 S 4.0, Cayman S 3.8, Cayenne Turbo, Macan Turbo, 69 911, Mini R53 JCW , RADICAL SR3 |
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Wo ist die Rennstrecke?
Join Date: Mar 2004
Location: St Johns, FL
Posts: 1,210
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Basically. JB did the port work and made the cylinders, and I timed the cams a little differently. Other than that and some software tweeks, its back to the original build.
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