Anyone here use or have experience with the Black Pixi line of engines? Any info on break in or other tips would be greatly appreciated

I use to have a black pixi 5pt. I let it idle for 1 1/2 tanks then slowly eased up from there. I was about 6-7 tanks into it before i got it into second gear. I think its a good engine but not for the money. I would get the novarossi ns12s5 if you are buying one. Best engine i have ever had

I have 4 Rossi's and they are as fast as any engine out today.


Mark

I appreciate the input, but Im not really looking to start a "Is this engine better than the rest" type thread. Id really be interested in your break in procedures. I have gotten some response in another thread, and if Im understanding this correctly, this guy removed all head shims and ran it in with 25 % and a high oil content fuel. Just wondering if others have similar history or if there's other suggestions.

NOOOO!!!!!!

Remember that you mainly want to heat cycle the motor and let the components settle to the running conditions. What this means is run the motor in with the same fuel you intend to run the motor on. Run it very rich for about a minute, then stop the motor and let it cool completely, do this for 2 tanks, stopping the motor after a minute and letting it cool completely. Then run it a little leaner, the same way you did previously. You may want to run the motor in the car on a bench with a fan, letting the motor idle. After you have leaned the motor on the 3rd and 4th tanks, Lean it to slightly rich, then run the 5th and 6th tanks. now the car is nearly ready, take the car and run it at MAX 1/2 throttle, but cycle the speed up and down, but stop every minute and let it coll completely, do this for one tank. Once this is complete, with the motor rich, run it to full throttle and down to 1/4 throttle, cycle this for a minute, try to get at least ten cycles in the minute, stop and let it cool, do this for a tank. You can now set the car up to race tuning and run it as you need.

You dont necessarily need to follow this, but I can tell you the you will get many great hours out of your motor. AND your motor will be easier to tune, and will make BIG power.

Regards...
Let me know how it runs.

This procedure will also work on a bench with a prop, in fact it is better on a bench, but break-in benches are in excess of $100.

I understand the heat cycle idea and will do that. But my main concern is should I remove this shim and run it. I am gonna use O'donnel 30% and my LHS gave me Rossi C-7S plugs.

Ok...good news...it took a lil while to get the needles right, but once I did, I got it to start and run very nice.I just finished the first tank.I started it up and let it idle through the entire tank rather than the start for a minute-stop,cool down, run for another minute method. I chose this because the temp, through the entire run, never exceeded 150 F. I figure to let it idle through one more tank, lean it a tiny bit, idle two tanks then lean it again, idle...simply keep repeating this til it idles consistantly at around 220 F.Then Ill consider tuning for race conditions.If Im wrong I appreciate any tips...thanks

Ok...well so far, six total tanks. Four at idle and two driving it, just barely blipping throttle, maybe 1/4 WOT. Pulled the plug out, and compression is still wicked tight, I can't turn it by hand with the plug out. Tomorrow I will run it more, but it isnt yet ready to be leaned. So far I am extremely happy

I am glad you are happy with it. just remember that the run for a minute and stop to cool is to heat cycle the motor so that it will be able to be leaned properly without damage. Just heat cycle it a bit before you lean it out. it is up to you what you do but after tons of research, I found it to be the best. Let me know how it goes, I nearly bought the black pixy, but found the Nova cheaper than the pixy and bought.

I wouldn't take the head shims out with 30% fuel. Most engines are shimmed for 20% average conditions. Usually you want to add shim to an engine to run 30% as the compression will increase, causing a risk of detonation. You won't have a problem with this during break-in cause the over-rich mixture will keep the plug cooler, but when you run in warmer weather with the engine leaner for race-tune, detonation is almost inevitable without any head shims. At least put the same shims back. Some guys remove them during break-in to compensate for the over rich mixture. The extra compression helps force the engine to idle better when super-rich. Keeping that sucker running is the hardest part of break-in. In some engines, running no shim can actually cause the piston and plug to contact each other.

I agree, and

I agree again...

Ok...well...now Im totally confused...although what you two say seems to make more sense than what I had heard in another forum. I was told that the Pixi is over shimmed????...I mean...
it is good with no shims for 30% and that to run a lower % , one would have to have the head button machined down. I can say, as for right now, it is running great. Although I have only run 8 tanks worth so far...despite beautiful weather, I have been sick all week and havn't had desire to do anything

ie....check page 20 on the STS engine thread and you'll see where Im coming from...

I see what you are saying. It would seem the individual who posted that info had taken actual head clearance measurements. You'd have to take your own measurements to be really sure. Just in case he had an improperly machined head button or something. I'd say if it is running fine, don't worry about it, just keep an eye on the temps and listen for detonation. You'll know when it starts detonating. It will have a distinct crackling noise and performance on the top end will be a bit diminished during all that noise. If the head clearance is in fact higher than typical than you should be fine.

If it aint broke, dont fix it...