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TR2/3/3A Tachometer vs rpm analyzer?

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GTP1960

GTP1960

Jedi Knight
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While my '60, 3A. Starts very well and seems to idle pretty well.
There is approx. 700-900 rpm discrepancy between the tach & the meter.
( so I'm wondering which one to believe.)

she is still running rough between 2k-3k rpm on the tach.
( hesitates & misses) but. Runs well above about 2700.

no vacuum leaks, timing seems good.
i plan on rebuilding my H6 carbs, because I don't know when it was last done & want to get a base line history going.

I' m going to try to attach a short video. Though I might try uploading to YouTube if this doesn't work.
https://youtu.be/C01qFqNVzAY

hopefully the engine sound will come thru also, because i've adjusted the valves and have a bit of clatter going on. I would like to know if I should try to adjust the valves again, or if a little clatter is ok.

your opinions are appreciated
 
Geo Hahn said:
Some clatter is okay IMO.

Was that meter indicating 450 - 650 RPM? Sounded much higher to me.
Click to expand...

Yes, the meter was indicating approx. 450-650.
I think your right. The meter must be way off, & I was setting my idle according to it.
the tachometer may be off too, but not that much.

think I'll hook the meter up to my truck and compare.

thx George.
 
Agree with you there. Engine sure sounds to me like it's running close to 1500 rpm as the car's tachometer shows. I wonder if your digital analyzer is failing the "auto ranging" function; it sure jumps around, even tho' the engine seems relatively smooth.

The "clatter" sounds like my old TR3, so seems normal - altho' audio on a youtube video leaves something to be desired.

Say, could you give more details on the "multimeter" you're using to measure rpm's? I've never seen one with a tachometer function. I think I should move up from my 1970s vintage analyzer.

Thanks.
Tom
PS - you can imbed a video here by just removing the "s" from "https" in the link you get from YouTube.
 
Better a little loose than too tight, but they do sound loose. My Vehicle Tach is right on, but some say they are off at the low end. The dwell will effect low idle. Try setting the dwell with a meter and then the timing and see if the engine comes down some. I think they dwell at 60 degrees and that is supposed to .15, but with my eyes that is just a hair. I find getting the idle down is tricky with these cars because if the idles is too fast then the timing is going to advance some plus the fuel today is different than they were designed to run, so I back the two off together on the road until I get the idle around 900. One thing that made a difference to get my idle down was I purchased an NOS distributor. It made a difference. I see that BPNW sells a brand new one for I think around 125.00. I will try that on this next project if I have idle and performance problems.
 
sp53 said:
Better a little loose than too tight, but they do sound loose. My Vehicle Tach is right on, but some say they are off at the low end. The dwell will effect low idle. Try setting the dwell with a meter and then the timing and see if the engine comes down some.
Click to expand...
I've got the new flamethrower 111 , and a 45k v coil ( maybe that's my problem.)

Say, could you give more details on the "multimeter" you're using to measure rpm's? I've never seen one with a tachometer function. I think I should move up from my 1970s vintage analyzer.
Click to expand...

i'll post pics and info tomorrow, but there were several to choose from on Amazon
 
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