I run Byron's in my Dynamite. IMO blue thunder is junk, I tried it years ago, maybe the new stuff is better.

Losi released some pictures of the Piston and Sleeve for the 350 engine. Looks like I was WRONG about the Dynamite Mach 2 and Losi 350 being similar engines. The Dynamite is listed as a 6 port, but the Losi is a 3 port. Oh well. Should've kept my mouth shut. LOL.

will the piston/sleeve be interchangeable between the XPS and the Mach 2?

I have a sneaky suspicion that this engine is a rebadged Sportwerks V2, no shame in that, the V2 is pretty fast and I hear they last around 4 good gallons before going weak then p/s sets will cost ~$50 or less. Not too bad.

I should be able to give you guys an answer in a couple of days, mine is supposed to arrive tomorrow.

More like 14 gallons The v 2 is one of the most reliable engines ever on the market!!

I've never heard of an engine that ran well for 14 gallons and I still don't think I have.

I had a Mach 427, from the RTR Losi 1.0 that ran well for 12-13 gallons before tuning started to become difficult. I ran it in that buggy for my first three club races when I acquired a Novarossi. Then I ran that engine in my 8T for the rest of it's life. It was awesome.

Piston & sleeve from my Sportworks 21 V2...

Exhaust side



Intake side



Transfer ports (other side is identical)



I believe this engine was described as a 6 port engine. I counted 7. Do you not count the exhaust? Or is the bridged intake counted as 1? Maybe some of you guys can educate me.

Incidentally, I've been running this engine for over a year now. I recently had it pinched and when I took it apart today I noticed some slop in the rod bushing. Is it worth trying to replace the rod or should I call it a day on this motor? I've got the dynamite coming and another Sportworks just like this one on hand already.

If the crank pin is still round (measure at a few points with a caliper) and you're confident that the bearings will go longer then sure, get a new rod and slap it in there. Not sure about the rhyme or reason on port count. It seems that brands are playing with the standard to suit their marketing ambitions. I say don't count the exhaust port. The vast majority all have only one of those.

Nice to see what a V2 looks like internally. I'll have to compare my Mach 2 when I get it Thurs. and see how it compares. Most of the engines I've seen don't count the exhaust port, so yes, that is a 6 port. How much fuel (gallons) have you run through your V2 and what kind of runtime are you getting?

Mine was supposed to be here today. I checked the Fedex tracking a little while ago and now it won't be here until Thursday...GRRRRRR!

I really have no good idea about how many gallons have been run through the V2. My guess based on how often I run my buggy and how much fuel I run through it each session would be 5 gallons on the low end and 8 on the high. It was my first .21 nitro and I did overheat it more than once early on so I'd say that it served me pretty well. I'm finally getting a feel for tuning these engines, so I'm hoping that the Dynamite will have a long life.

Ooops! You asked about runtime too. I usually get 7:30 to 8 minutes with a Dynamite 053 pipe. I usually try to pit at 7 minutes and again at 14, that gets me through a 20 minute main on two stops.

Alright well, I have been on the scene for for abit

Rebuilding these small engines is a waste of time, I have seen novas, os, and many others fail after a rebuild with cracked cases.