Popped through the intake.

[Pmt133]

Those look good, maybe could go a tad richer, but no sign of water or oil

To me, considering a fresh rebuild with basically no idle, 1,3,5 look perfect. 2,4,6 look slightly lean.

 

[Scott06]

To me, considering a fresh rebuild with basically no idle, 1,3,5 look perfect. 2,4,6 look slightly lean.

this is one of the best spark plug reading tutorials I have found

Wallace Racing - Spark Plug Reading

 

[Pmt133]

this is one of the best spark plug reading tutorials I have found

Wallace Racing - Spark Plug Reading

That is the one I reference as well. Which is why I say it's pretty good all things considered.

 

[Pmt133]

So, I finally got around to checking everything. No water in separator, no other glaring issues however I did find out that the choke was staying on longer than it should. Like it would choke for 2-3 minutes on a 70 degree day. So I readjusted that and suspect that could've been the issue. It very easily could have gotten knocked around while it was in the garage waiting for the rebuilt engine.

Anyway, I ran her very hard to duplicate the issue and then some and didn't get even a hiccup. Only other difference is it was 75 degrees out not 90. Time will tell but for now, I will say this is resolved.

 

[Pmt133]

I will also add I've been testing some of the props I have on hand and thought I had a problem the other day. Trying to hit wide open I found it seemed like it did the same thing but I backed down so quick I didn't want to prove it. After doing a little research it seems the thunderbolt 5 had a rev limiter set around 5k which makes sense and would be about where I had my issue the other day. This confirms my tachometer is off about how much I measured it to be.

 

[Scott Danforth]

I think the rev limiter is like 5100 rpm IIRC

 

[Pmt133]

I think the rev limiter is like 5100 rpm IIRC

I didn't catch the exact RPM and I haven't found any real mention of it in the limited literature I have other than it is approximately 200 RPM above wide open RPM. 5100 RPM would be in that ball park based on what I saw. Thanks for the info.

 

[Pmt133]

Went out again today, had to take advantage of this lovely weather. I left nothing up to the imagination this time. I flogged her hard. Not even a hiccup. I'd almost say she's running too perfect as I actually picked up 2 mph and 150 RPMs. I'll be out again tomorrow as I'm hearing low 80s for daytime temp.