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BN2 clutch pedal and exhaust downpipe

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349A

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My new to me BN2 has an odd issue, when the clutch is fully depressed, the pedal arm hits the exhaust downpipe. It makes for an interesting musical instrument at idle tap tap tappity tap. The downpipe is stock. I notice Moss mentions this as a possibility in their listing for a stainless exhaust downpipe with or without a stock downpipe. Is this truly normal or am I missing a pedal stop? Thanks!

Jonathan
 
I'm returning from overseas so I can't go to the barn and look at my car but I do recall a clearance issue but cant remember what I did when I got to that during my rebuild. If nobody answers you before then, when I recover from jet lag I'll take a look and let you know. Might it have to do with the direction a bolt was installed? Often a bolt head will have clearance where the nut side will protrude further so as to not have clearance. Have you looked at it from underneath?
 
349--

It's a close fit at best. Is the stabilizing bracket between engine ans pipe in place?
 
Thanks Jon and Michael. I’ve spent some time underneath and all looks like the factory diagram from what I can tell. Having never been under another 100, I don’t have a reference besides the drawing.
What does the stabilizing bracket look like and where does it mount?
The car is out of a five year Healey Werks restoration by the PO so its pretty thoroughly done. Basically ever nut and bolt is restored so I’d be mildly surprised if something was missing. Its definitely possible. Downpipe is stock as is the whole exhaust.

Jonathan
 
Look at the exhaust page in the Moss catalogue. it is a piece of metal that mounts between and to the block and the exhaust, designed to stabilize the latter.
 
Yes, that's the piece. It is often missing.
 
My clutch pedal just hits the downpipe at full travel, and I do have the support bracket (it doesn't change the location of the downpipe). I've been told some cars, at least, had the issue from the factory.
 
Interesting, Bob. I wonder why only some. Same with mine, when really pushing it all the way down, it hits the downpipe. When the car is cold and idling a little low, the lope causes it to rattle against the pedal.
I’m considering changing to headers anyway, I wonder if that will solve the problem or make it worse. Looking into the DW 100M setup or the Cape International stainless setup.

Jonathan
 
Well, I kind of hedged a little; I heard they all had the problem but, somewhere out there somebody doesn't and I would have been technically incorrect. I've considered getting a period-style header, as my car is a 100M, but it would have been as much to eliminate the annoying 'pedal knock' as for any HP improvement (I think driving these cars much over 3,500RPM is a risk anyway, as crank fractures are also a known problem). I've just gotten in the habit of not getting the last inch or so out of the clutch pedal; in fact, since the problem is endimic maybe a little spacer on the backside of the pedal might be a worthwhile bandaid*.

* Edit: I've read--in my Mustangs' owners manuals IIRC--something to the effect that 'the clutch pedal needs to go all the way down.' No explanation given but, obviously, if your clutch isn't fully disengaged you'll grind your gears and possibly damage something, but the clutch should be fully released before you floor the pedal (probably no more than, say 3/4 of travel at most). Anyone know the reason for this warning?
 
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Bob- good points about RPM and cranks. I tend to only get up near redline for brief periods when the mood strikes. I normally shift around 3500-3800. While I don’t expect much in the way of HP with a header, they sure sounded nice. Sound/sensation a big part of the joy of vintage cars. Not to mention how pretty they can be. I’m hopeful a header might also give the small extra clearance, I suppose that would be nearly impossible to know unless one installed one.
Clutch all the way in- I was always taught to press it to the floor. I’m unsure exactly why. I would assume if its fully engaged, its fully engaged!

Jonathan
 
Thank, Bob. I have read that at least twice. It seems the fatigue/breakage issue becomes more and more of a threat if one keeps the RPM’s up often. Its accumulative, a ticking time bomb with no reset button. Of course I have no idea how the car was driven for the first 70,000 miles. Hopefully gently.

Jonathan
 
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