How Does My Break-in Look?

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REVO-5309

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  1. Bashing
So i just put 7ish tanks through the new motor. I'm running 30% nitro and I'm running 0.4mm head shim instead of the factory 0.3mm, i seems to have it pretty much tuned. i read somewhere about it detonating or something and was wondering if this white stuff on the glow plug has anything to do with it or if i was just running a bit lean? is it suppose to look nice and gold like that, sign of rich I'm guessing? also the head didnt come with the new motor but its not that old itself.

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What color is your fuel? If the plug looks like it has white stuff on it I'd say it's lean.
 
fuel is green, kinda like a lime green.

---------- Post added at 10:05 PM ---------- Previous post was at 10:04 PM ----------

also is the shim correct, or should i go back to 0.3 or go up more to 0.5?
 
Okay, I should know this by now, but what the heck is a head shim and what does it do to the engine?
 
It's the head gasket. It effects the compression. More nitro in general required more shims. To how many shims are needed I don't have an exact answer
 
Adding shims can prevent detonation, which is the air/fuel mix firing prematurely....kind of like a teenager on his first date.:hehe:

You don't have to add shims on a 3.3 for 30% nitro, but you probably won't notice much difference with the one you've added. A stock 3.3 with with 30% and a hot plug should run fine unless it's cold outside.

Whenever you have doubts about your tuning it's always best to richen the hsn and lean it back in from there.
 
If I'm running medium plugs is the extra shim compensate for the hot plug? I don't have any hot plugs here and I'm not buying any more stuff for The trx3.3 as I'm waiting for my picco 26 jlr.
 
do the glow plugs show your tune like a 2stroke? I know white is lean and black is rich
 
yes glow plug shows tune.
 
They do, but wet is rich and lean plugs have a dry grey look to them.
 
And what's the go with medium and hot plugs with shimming? Can I increase or decrease shimming to immitate a hot or medium plug?
 
The medium plug will give slightly better top end power, the hot plug will give a better idle and low end performance. You don't really have to fiddle with the shims on a 3.3, but removing them will advance your timing and adding them will retard the timing.
A hot plug will advance the timing and a medium will retard the timing......simply put. There's more to it than that.
 
so if i go back to 0.3mm shim it would be advancing the timing but also increasing compression.
 
Yes...in a nutshell. You'd probably never notice the difference. If you have a good idle and low end power then the medium is just fine.
 
yeh iv almost got the idle closed its that low and its pinch test is between 2-4 sec if its a little less than 3 after its warm and has a full tank ill generally richen up a touch. but apart from that a few tanks past break in and its running pretty decent.
 
does this carb opening look good?

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It's hard to tell with that picture, but it might still be too much.
 
These is where mine is set, idle is realy good per tune as the temp here in TX. I'm sure you know these is the new 3.3 I broke in with all yall's help. Concerning with a bad trottle servo, it has great response on take off. The darn thing is better than the other 3.3 I had to replaced, these one always want's to be on 2 wheels on take off. (with same slip clutch adjustments) I think just a bit of experience of me, now that I know abit of these Nitro stuff. Yes, still learning tho.

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Man, we must have same temp Tx & Aus. Those gaps almost look identical. Are you in The land down under?
 
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