UnkleLumpY

So a member of the forum here turned me onto novarosi, pretty impressed with the vids and information I've been reading. Unfortunately, nova carries a higher price tag, but I found one I like thats in my price range. Looking at a Rosi 2.5 super charged w/tuned pipe, would it work on an ofna lx2 1/8 buggy and would I be drastic power improvements in the low and high bands over the force .28 I'm currently running?

*Sorry if this sounds like a newb question, but I'm totally newb and totally hooked on nitro now. Been running a wore out force .28 and just wanna get the most out of this buggy.

1QwkSport2.5r

The 2.5cc is a .15 ci engine - your current engine is a .28ci or 4.67cc. Nearly half the size. Your buggy would not perform very well with the 2.5 engine I'm afraid. Plus you'd need to change to a smallblock engine mount and re-set all of your throttle linkages and brake linkages. A big block engine .21/3.5cc or bigger is going to be your drop-in choice.

UnkleLumpY

Well, I got a new engine. The novarossi was too much to change everything around, so I went with a hobao Mach.28 6 port that was a direct fit and everything switched over with ease. While having a lil less hp than the force .28, she spools up much quicker and has a much smoother and more consistent power delivery. Still at the tail end of the break in period, just now starting to wind her up full speed and it's VERY torquey, get up to speed very quick plus with a mid range needle to rev up is extremely smooth and impressive, however I think I lost top end speed. Before I would drag race my father in law's stampede vxl and I would fall behind in the start and catch up in the back end, now I get a jump off the line and he catches up in the back end. Hopefully the engine will just improve with further break in. Also running losi nitrotane 30-12 and I'm not sure if it helps but since this engine runs hot by nature and it's rated as a "competition" engine I'm hoping the losi fuel is helping

1QwkSport2.5r

If it runs hot, it's not setup or tuned correctly. True competition engines like Novarossi and Picco run all day at 200-220F - modified engines even lower in some cases. Trying a colder glow plug may help.

Read your glow plug. The color of the plug and wire element will tell you how it's tuned.

UnkleLumpY

Running a hot long right now, suggest I use a medium/medium?

1QwkSport2.5r

Always use long reach plugs - that's what the engine is designed for. I would get a cold and a medium heat range plug to try. . Colder plug will allow a sharper tune and will make more power and are a bit more durable.

What brand plugs are you using?

UnkleLumpY

What ever the lhs has, I believe they are OS

1QwkSport2.5r

Try using a McCoy MC8 and MC9. They're cheaper than OS, the right length (OS is medium length), and last a long time. I've used McCoy for years and really like them. If the LHS won't get you any other brand, order some online. I hate OS plugs. I've never been happy with how they run - probably in part due to their shorter length.

I'm a stickler for using the proper length glow plug in engines. If it's supposed to use a long plug, I use one unless I've got no other option.

UnkleLumpY

Ran two more tanks today, on tenth tank now, last tank I ran it hard and she performed well, but definitely lost top end speed so I'm a lil bummed about it. I'll order some long cold plugs and try them out.

1QwkSport2.5r

If you didn't have a way of measuring your top speed before, how can you be sure you really lost speed?

The top end scream was elusive to me for a long time - I run Losi Monster Trucks... Been running Losi/Mach .26/.28 engines in them for years. Finally decided to get something with some real punch - so out with the old and in with the new... Nova Legend 28-8RT in one LST and Picco P3 .28 in the other. The Nova is still stock with 41017 header and 9886 pipe, but the Picco is modified and uses a 41016 header and Dynamite 086HS pipe. The Picco truck is the one I run all the time - getting it broken in good. I'll just say that it would be worth your while to save some $$ to get one of these better engines later on down the road. The power and ease of tuning is so easy. Use a cold/medium plug and a good dose of nitro and they just rock. I'll have to make a video one of these days - These things scream.

UnkleLumpY

For top end can visually see on high speed pass by runs and the fact that my father in law's brushless stampede now catches up in the back end of the drag race. Now I get him off the line and he catches up in the tail end. Before it was opposite. This engine definitely does scream loud at high rpm (louder than previous) and it holds a tune, so that's real nice but I would love to see a vid of the nova though, as for pico it seems to be a 50-50 split, some ppl swear by them while other say there's nothing special and it's just a name.

1QwkSport2.5r

The Nova 28-8 and Picco P3 .28 are pretty even on power. I've never had a Picco before this one, so I don't have anything to compare it to except against my SH based engines. The Picco takes a long time to break-in because it's so tight new, but it holds a tune fantastic and has heaps of power. When I modified it, I basically moved the powerband higher in the rev range. They have gobs of low end torque which makes a big heavy MT wheelie happy. Moving the powerband up higher takes away from the bottom end some so the truck is faster on top and spends less time on the lid.

Try using a shorter manifold and top end pipe. The conical Nova manifolds are much more efficient and often the manifold has more impact on the engine and how it behaves than the pipe does. On a buggy, you may want to try a 41032 Nova manifold and 9886 pipe.

1QwkSport2.5r

Here is one of Supertib's dyno graphs showing the differences between several manifolds. He used the same pipe and just changed the manifold, so you can see how much the manifold alone can affect power. http://www.rcuniverse.com/forum/rc-c...l#post12249059

UnkleLumpY

The Rosi thing WILL happen next year, I wanna get comfortable with the whole nitro aspect before dropping bukoo $ on a race ready engine, until then I'm just gonna tinker, with that being said, would either of these show improvement over the stock force.28 exhaust system


http://www.ebay.com/itm/311640509523...STRK:MEBIDX:IT



http://www.ebay.com/itm/351806091569...STRK:MEBIDX:IT


Btw that is for putting up with my newb questions and ty for all your help!!

1QwkSport2.5r

I don't know anything about either of those, so I can't say for sure. I can say you would be better off just buying a different manifold to start with. The pipe has some effect on the engine, but the manifold has shown to have more influence in a lot of cases. Try that 41032 Nova manifold. They're relatively inexpensive through novarossidirect.com.

UnkleLumpY

Wound up getting to ofna header/pro pipe combo, had good reviews and the seller was selling WAY below market value.Trust me I'm sold on the novarossi, but like I said, wanna abuse and learn on cheaper stuff before I buy I finely tuned and engineered Italian high dollar engine

But maybe you can answer this, since it's a single cylinder, how can these "headers" be real legit headers and not just manifolds? I have headers on my Chevy truck and the purpose is for each cylinder to expel exhaust gasses individually per cylinder increasing power and torque by increasing the efficiency of how the engine breathes. I guess I don't understand how RC engines can have headers.

1QwkSport2.5r

The manifold I suggested (Novarossi 41032) is just the manifold, not the whole engine. The manifold will fit almost any engine. As I said (and if you looked at Neal's dyno graph) the manifold can have a significant impact on the power of the engine. You wanted more top end, and that manifold will likely do that for you on the same pipe even. Not a guarantee, but the conical manifolds make a nice power boost usually. But you'll have to see if your new pipe/header works better than the one you have now.

On a single cylinder engine, manifold and header are used interchangeably. Generally headers are tubular in shape and manifolds tend to be "blocky" cast pieces. Headers (tubular) will flow better and smoother than a manifold and the conical headers will flow better yet and allow the exhaust gasses to transition to the pipe's first chamber much smoother (in a nutshell will boost power).

I have found that that if the manifold is too long, the engine won't rev as hard, will have less top end, and the engine can run hot. How the engine responds to the pipe/header is dependent on the timing of the engine, size of the carb, length/shape of header, and pipe chamber shape/volume. Lots of variables to consider - throwing parts at an engine can lead to disappointment when your particular engine doesn't respond as well as other engines. Do some googling on pipe/header combos on RCTech. I think there's much that can be learned.

UnkleLumpY

Awesome man, Thanx. Maybe I'll look into upgraded carbs too

UnkleLumpY

Well I just installed and ran the ofna pro tuned pipe and pro header, it's a short header and doesn't even bend completely around in a "u". First I noticed it was much quieter, which took me by surprise. After a slight tune and a warm-up I started letting her rip. Didn't gain anything on the top end but gained a massive amount on the low end, winds up extremely fast now, so much so it laid rubber from all four wheels, so I guess I'm ok with it now. If this budget competition engine is performing like this, I can't wait to see what the legend 28 does!