On my new Max Power Extreme engine I have just over 3/4 a gallon through her- I did the breakin heat cycle stooopid rich tank idles- head wrapped- high idle- full throttle- with heat gun applied pre and during tanks- then drove it conservative with head wrapped still progressively leaning until where Im at now- a bit more than 3/4 gallon.

Still I cant turn the engine over by finger when its hot! it gets stuck and has quite a lot of pinch. I would have thought it would be further along the loosening up process. This is my first break in from start to finish.

The real issue is the car off the line (only 10% throttle) just about always has a delayed reaction and I think I have pinpointed it to just being not broken in yet and sticking at TDC? Does this sound about right? I set my idle gap well, I am an above average tuner and troubleshooter so I believe my tune is more than close enough for this stage of breakin for it to at least take off smoothly. The clutch is a new Buku so I dont think its the clutch. Factory settings atm. I was also having issues with the engines immediately stalling as soon as I took the ignitor off- the the engine finally warmed up and I leaned it a little bit and it started to run so I dont think its the plug, fuel or exhaust either. I feel its sticking at TDC as the other symptom I had I heard can be caused by being stuck at tdc (engine dying when removing ignitor). Does this happen with new engines? delayed start off the line?

I hear ya... I don't think it would totally be sticking hence or else it would stall as you referred to and that makes sense- but what if it's just only sticking slightly? just enough to cause a quick delay in response then the power kicks in? I say this because some of that pinch is gone and it gradually gets tighter- it doesn't just get halfway into pinch zone and completely get stuck- its more progressive thats why Im thinking it may not be getting stuck enough to stall out but cause delay. Any other thoughts guys? I should mention Im running a 9mm insert. I heard low end response can suffer a little with a 9mm but never heard of a it causing a big hiccup before moving so to speak.

Could be too lean on the LSN, that may be caused by a too long back pressure line or a blocked backpressure line.

Thanks for your response! much appreciated.

My pressure line is very short ~4.5 inches
My fuel line is even shorter ~2.5 inches. Only goes from nipple around filter neck to the tank nipple- really short like the rtr MP9


Funny you mention lean lsn because I absolutely thought that first as the lsn will only run when its far in like 4 turns in. This is the only way to keep it running during breakin running on the ground. I think it's too lean but it's blowing smoke a lot of smoke from low to mid acceleration. If I start to richen the lsn it wont idle and yes adjusting the idle too.. Im flabbergasted Everyone that runs Novarossis say between 1-2 turns in on lsn and about flush to .5 turn in on hsn and that's a race tune!! i'm way further in on lsn and its rich.

Think its my 9mm carb insert and pinch?

Your needles are backwards if its blowing smoke but running to lean. You need to set your needles to factory settings, which inside your box in the instructions it will tell you what they are, if you don't know on Nova engines its about flush with the top brass collate on the HSN and about 4 turns out from bottom on the BSN. Also you say you have heat in the engine and its still getting stuck. How much heat? what temp? If you are new to breaking in an engine then you need to be using a temp gun or have someone that knows what they are doing to help you. You need this engine to be as hot as about 240 during break in. Look up Adam Drake on YouTube for videos on engine break in, he uses or suggest the easiest way to break in an engine till you get more comfortable with doing it. There are many ways to do it, he suggests the easiest way to break in an engine for someone new to the hobby. Also get you some new fuel line. Dubro makes some decent line and cheap and tough. Doesn't have the best mileage but will get you going. Pressure lines is no less than 6 inches, and fuel should be that or a little bit more.

Roblupo, did you ever try the / header on the Memphisto?

I didn't. I haven't been running it much lately. Its a good running engine but its only better for smaller tracks. I ran both the 41021 and 41031 headers

Hello everyone. I have been in the nitro world 15 years now as a basher. Have seen many motors come and go. I always replaced them with cheaper knockoffs. But I have decided a nova is in my future lol. It will be living in a losi 8ight. I bash but also do a lot of high speed runs. I am leaning towards the rex 28-8 I keep hearing all about. I am open to other suggestions as well. But the rex I can find new from $190 to $300 why such the price difference? Is there an older and new model? None I have seen say the are modded. This dynimite. 21 just isn't enough. I swear its loaded rpm sounds like its barely over 15,000 rpm. I know all you nova guys wont steer me in a wrong direction. Thanks ahead of time.

Looking at replacing my Ultimate M3T with a Novarossi Mephisto

How are people finding their Mephisto motors overall happy with them ?

Mephisto is a good engine over all with all the goodies that people want to have like OS engines. Its overly smooth on the bottom in my opinion which if you run it with the right pipe and clutch setup its still very good. Has a lot of pull for long straights and the head keeps the engine really cool. Over all its a good engine, but there are plenty that are cheaper that will perform better is my thoughts. Depends on what you want.

I still belive you should test the Mephisto with the / header. Thoose manifolds are much better than the long curved ones-like 41021 and its siblings

Is the mephisto still listed as square stroke but is standard novarossi 16.8mm stroke like the mantra?