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Dropping the exhaust and the airbox made no difference :(

Looking into the problem with the builder...Possible cam timing issue!?

Can you get a copy of the dyno sheet? Should show if it is cam timing out, eg power curve heavily shifted to the low end etc.

  • 4 weeks later...

UPDATE!!!

Ok so Tomei 256/8.5 IN&EX cams + adjustable gears were put in.

Car was timed using DIAL GUAGES. Builder said that he had to run 7-8 deg advanced on the intake side and 6 deg on the exhaust side from "zero" when the dial guages displayed that the cams were in the right position ("zero'd" as you would with a standard type setup).

Car was chucked on the dyno...From what I was told in conversation, the ignition timing was measured with a gun so that the ignition timing on the computer could be verified. For some reason the timing was 10 degrees out (advanced from memory). I have no idea why this was the case as the computer was not touched since last time the thing was on the dyno. So the timing was reset in the computer.

Few runs were conducted. Timing was played with up to around 8-10 times on both the exhaust side and intake side. But the thing still wouldn't make more power than about 250RWKW. Much lower than you would expect with the cams + turbo + motor setup.

They took it off the dyno for lunch. Cooled down, then ran it again...Made about 5RWKW more.

So all up it finished with about 255.5RWKW at an A/R of about 11.5-11.8.

See dyno graph below.

Still reckon its a timing issue?

post-12041-0-24832500-1317975671_thumb.jpg

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