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Pinking, Knock, Plinking etc.

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prb51

prb51

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Guys/Gals,
I'm doing my winter tune...a few more degrees advance and a one flat richening of carbs for the cooler air. The TR3 is running well but how does one hear knock in our cars unless it is extreme.
With the valve clatter (open car with brooklands, yes even in winter {Arizona winter}), wind noise, car noise etc how do you detect light knock?
Do you check for this in your garage while parked and no engine load? Will it show up properly under no load?
p.s, my military ears ain't what they used to be either....
 
Get it warmed up and go for a ride. Find a hilly area with quiet streets. Drive as far up the hill as you can in fourth gear, lugging the engine down to low rpms. If it starts to ping early, back off the advance. No ping until you have to shift down, no problem.

Remember that it will first and always occur when the engine is under a load and the best way to duplicate that is above or something similar.
 
If your tappets are that loud, there are some options. Temporary options are do nothing or adjust valves. Long term options are to have the rockers and shaft rebuilt or buy new.
Adjusting the valves(if the rocker faces are worn) tighten up your clearances a thousandth or two. Over time, the face of the rocker forms a groove where it makes contact, and tightening the clearances can help offset this wear.
If your engine is fairly new, adjust the valves as per factory spec.
If the rocker shaft shows excessive wear at the bottom were the rocker rides, replacement or rebuilding are the only options. Excessive wear can alter the rocker ratios and cause poor performance. Very excessive wear can cause binding and really alter engine performance.
I recently had the rockers rebuilt on my TR6. The company reamed, bushed and refaced the rockers to the original ratio. I had already purchased a new shaft. It eliminated all valve clatter and increased performance nicely. I consider it money very well spent. Rebuilding was less expensive than new.
 
Some day I'll get them rebuilt but the car runs really well as is. I use an extremely slim gauge (thinner than the rod head ) to measure and they're set properly...they just clatter a tad.
What did it run for a rebuild approx?
 
For me to just have the rockers done and I gave him a core rocker shaft, with shipping was around $175. A friend of mine had everything done on a Bugeye for I think a little less.
I thought my car ran pretty well also, but the difference was very surprising. It now runs perfectly smooth at idle.
I had this shaft built for an engine I plan to build over the winter. Somehow it doesn't seem right to pull a perfectly running engine out and replace it with a new project.
 
Doug,
Decent price for the work and I suspect I'll get around to it (after my tranny upgrade).
I took the car to a steep side street and lugged her up in 4th and couldn't hear anything different noise wise so I'll stick with what I've got.
I agree about your engine if it's 'right' as is. Just rebuild the other and have a 'stand by'. I'd not rebuild it to have it sit though, I'd wait until the other needed freshening so everything will remain tight.
 
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