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Old 08-27-2012, 01:00 AM   #1
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Default Help me diagnose this problem please......

Since fitting my built engine I have developed a strange 'tingling vibration' through the pedals when changing gear at high revs. I didn't have this before so I guess it's something I have done and I can only think of 3 things it could be:

1. Clutch - I fitted the old ACT clutch by the book using an alignment tool, the plate had 50% wear and seems to be holding very well.

2. Braided clutch line - I removed the old hard clutch line completely and replaced it with a braided line directly from the master cylinder to the slave ( car is RHD).

3. Fitted competition engine mounts.

Has anyone had these syptoms? I would be grateful of help as it is starting to worry me and I have the car booked in for a full dyno tune tomorrow!

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Old 08-27-2012, 04:27 AM   #2
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The motor mounts are the only possible cause of the 3 you listed.
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Old 08-27-2012, 04:36 AM   #3
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When do you feel it? When your foot is resting on the clutch and about to shift, or when you've pressed the clutch already?

All three pedals?
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Old 08-27-2012, 04:39 AM   #4
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If the comp (read: stiffer) mounts are new to you, welcome to the wonderful increase in NVH when you go to stiffer engine mounts.

Engine mount selection can frequently become a tradeoff between NVH and stiffness.
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Old 08-27-2012, 06:29 AM   #5
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Thanks for the replies, I got this when depressing the clutch at high revs and when I released the clutch, but I can also feel it slightly on the accelerator.

I have just unbolted the 2 engine mounts, jacked up the engine a fraction and lowered it then torqued the 2 bolts back up.--Took it for a spin and the vibration is nowhere near as bad so it does seem to be engine mount related.--I did notice when I put the engine in, the drivers side mount sat high (the one with the slot, the nut sat half way in the slot), I forced it down so the engine was level, maybe that was the issue and now it has settled it sits properly.

I think I can live with it as it is now, I really didn't think comp mounts would make so much difference, ah well you live and learn.......

Cheers guys,
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Old 08-27-2012, 06:54 AM   #6
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Maybe you took some twist out of the mounts when you lifted the engine? My race mounts only noticeably increase NVH at tickover.
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