Start with a 41021 (medium) or a 41020 (long) header with the 9901 pipe. There are big differences with those headers :nod:

Questions about BTTA.
 

I have a BTTA with about a gallon break-in on it and its runs good but last race it was hard keeping the temps up. The motor is coming off at about 180 but almost seems like its lean bogging on the bottom but it runs good on top. When I try to richen the bottom a hour or so it loads too up quickly but when I lean it a hour or two the idle shoots up even with proper gap. My needles are both just about a half to quarter turn above flush. Anyway what I'm asking is where is a good spot to start with needles on my BTTA when race tuning also what carb insert do you recommend for a tight technical track? Thanks for any replies!

A good place to start is flush on both, You'll probably turn the top in more than that. Check and make sure the carb is not loose, that can screw with the tuning. 180 is way too cold. We were running 220-230 in 20 deg weather. Something does not sound right with what your doing.

Lean lsn , adjust idle then try again , probably have to richen hsn :nod:

Yeah it's probably closer to 200 I use a cheap Duratrax temp tool and I also seal all my motors as soon as I get them. I preheat to 200 before each run and I ran a sock on the head during first couple quarts to keep temps over 200. Our track is pretty big but real tight and technical so I think that has alot to do with low temps but I am going to flush the needles and check idle gap then test and tune some more. Thanks for the info guys!

any new, exciting , 2012 off-road engines coming down the pipeline? :tire:

How fast you wanna go ? ;)

lol,,,i want A Smooth, reliable race engine, for my new xray xb9 buggy when it gets here, last buggy motor i had was a houston tuned plus4c-team, and that was smooth as butter!!!! Not sure on the current crop of motors, is nova putting out a new lineup for 2012?

Have a look on the Novarossi web site there new line of 2012 are up same engines just a few changes.... The BTT in standard form is a perfect power plant for the XB9 All Tho a filled crank would make it just that bit nicer....

What does a silicone filled crank do?
If you remove material from the crank, the crank would be lighter if you add silicone instead and with or without material removal the flow through the crank must be better with the gentle curve the silicone makes.
But, can you feel the difference at all?

you cannot push mixture..the silicone does nothing for the flow.....mixture will naturally follow the shortest path on its own...putting filler there can actually slow it down as it creates drag.....short side radius is what matters....... putting filler in the crank just stuffs the crankcase volume a little...

If you want smooth AND powerful across the entire RPM range, you should take a hard look at the CRE BTT. It is the perfect buggy engine IMO.

If you want something that is more punchy down low but doesn't rev out to the moon, the FM X3 is also very nice.

I have a CRE Nova P5 otw and I am told it is the perfect balance between the two mentioned above.

Of course I prefer modified engines over stock units, so I have no idea how they compare in stock trim.

Nice Neal!

Thanks a lot :nod:

silicone filled intake ramp does do a few things , most noticeably the reduction of the staged idle by filling an airpocket that completely disrupts incoming flow of air/fuel when going from high vacuum to low vacuum on the intake of the crank , noticed a HUGE difference in the way the engines tuned off throttle and it threw me for a loop back in '06-'07 ish when the 821b was the first engine to come with the lightened crank that was unfilled . one thing i can tell ya is every single one of my multi repeat customers from all over the world have tried both and prefer a filled crank , we all do things a lil differently , we all have different opinions , we all feel things that others dont .


i have met well educated people in all different fields who thought they were the masters of what they studied in miss even the simplest of things looking a project over because they were too concentrated on the "deeply technical" aspect of the job ;)

If im running a BTT on 30% should i remove any of the head shims?

Not necessary , but rearranging shims (requires other shims) to achieve .70mm will feel a bit more responsive but I wouldnt suggest doing so til after metal to metal friction is gone

Thanks Monty.
Makes sense :nod:

What do you guys use to pre-heat your engines? I have a heat gun, buy I'm looking for something I can turn on and walk away from for a bit.

Competition heater. It's the greatest thing sense sliced bread.

Agreed!

Comp heat is THE WAY!

Hey Houston, I have a question, I have a bonito with about 1 gallon now and I am using the 6.5 insert so is that a good insert or should I go to a 7 or 7.5 I run this in a truggy, also how would this affect the run times? I am getting about 8min right now

Thanks in advance

I got a +4 BTT.. 3 litres old, It flames every fuel/pit stop sometimes in pit sometimes 1/4 lap out. Can someone tell me why? I checked all lines/tank all are ok. Its flames after refill when tank is close to empty. runs great up to the pit stop.
Any help would be great.. Cheers

Have you tried to lean the LSN an hour or so?

what fuel and glowplug do you use ?

I had the exact same issues recently. It turned out being my manifold gasket between the pipe & header. Looking at it from outside it looked fine, but once I separated the pipe & manifold, I could then see the gasket was trash.

It ran OK under throttle because the pressure was still high enough to help push the fuel. The flame outs occurred at idle because there was not enough tank pressure due to the fact it was escaping between the pipe & manifold.

Just something else to check.

Nitro X 25% with C6TGH Nova plug.
I was actally with Savage sam at Geelong last weekend when it was happening. But he wasn't the problem..LOL..
Neal

what oil % ....your plug may be a touch too cold , which would make the engine more sensitive...

Like Neal said that plug is the onroad plug c6tgh is pretty cold compared to c6tgc

Like strangdazd says , check all fuel pressure/delivery components before blaming it on the engine, 99% of the time you will find something wrong

Is it a mugen?

Is it a mugen?[/QUOTE]

Yes it is a Mugen
Sorry the plug is a c6tgc

how did I know ? ;)

Tell tale sign your novarossi isnt properly tuned , runtimes are not good :nod:

8 mins just

ok guys

i have a nova 3.5 pluss on my losi l8ight model. i have been running 20% fuel with a OS P3 PLUG. I ALSO HAVE A 7.5MM INSERT IN MY CARB. i still have a relatively tight pinch so i have some more breakin to go. my question from you guys is i want to race using 30% VP Racing fuel. What glow plug should i start with when i change? also should i change now and finish the break in or stay whith the 20% untill finished?

thanks for any opinions and knowhow you guys share with me.
edward

Yes it is a Mugen
Sorry the plug is a c6tgc[/QUOTE]

I'd say its your fuel tank. Mugens are known for that. Try replacing the o ring in your tank lid.

Plus4 flaming out
 

Hi all,

I have a Plus4 which has done slightly over a gallon. Still has very good compression and it was running well till recently ive changed the fuel. Simply cant get to tune the low end right. Was previously using the 30% Maxina Orion and now switch back to 30% Byron. Tried to chamge to the turbo button head from the std button head and use the Odonell 97t and c6tgc but to no avail. When i set the lsn a bit rich, it will just flame out aft idling for 10secs when i punch the throttle. When i set it a bit lean, eng will kept on reviving at high rpm n when i tune down the lsn.. Punch full throttle aft 10sec and eng will flame out..
The only way i can keep the engine running is to keep the idling high..
It cant be the tank or the fuel lines as it works fine with my xzb. Btw, im using a dyn053 pipe. Hsn is 3 turns out, lsn is 4turn out and idle is slightly more then a turn out from close without the 7mm venturi.
Thanks

Finish the break in on the 20% and OS (?) glow plug, you mine as well use them up. I'd then switch to the Novarossi C6TGC plug and VP 30%, tune it in and let it rip. The 7.5 insert should work fine, many use 7mm...others use 8mm, so you're right there. ;)

Best of luck!

Did you make sure to transfer all the head shims?

Sounds like youre in the ballpark with the needles so kinda interesting ,

outside temps are?
If its colder out you might try c5tgc instead

Finish the break in on the 20% and OS (?) glow plug, you mine as well use them up. I'd then switch to the Novarossi C6TGC plug and VP 30%, tune it in and let it rip. The 7.5 insert should work fine, many use 7mm...others use 8mm, so you're right there.

Best of luck!


yeah the plug package just said os P3 ultra hot or thats all i remember anyway.

and thanks i only have about half a gallon of 20% left so i was hoping and even leaning to finish it off then switch. i can order the nova C6tgc plugs and switch over all at once.

thanks and have a good day

Fyi: if you used OS plugs in Your novarossi you should continue using them, suggest p4 though

Hope this helps

I have been meaning to comment on this one, but have been too busy to sit down and do it !

Anyways every engine is different in how it responds to having the crank stuffed.......some engines pick up power, some lose power....... I do not think the ramp itself has much effect on the mixture path and the differences we do feel are a response to the change in crankcase volume more then anything else...... But where I have seen the ramp affect the engine is when too much silicone is used to ramp the crank and it gets in the way of the mixture path...this hurts power, and I have seen it on the dyno......... If you think about it, the more places the mixture makes contact, the more separation it experiences ..just like sticking your fingers in the patch of a spray can.... The less we contact the incoming mixture the better the mixture flows with the least amount of separation.. All too often i see cranks that are over stuffed ..which not only causes a loss of power, it also reduces the engines mileage........Some factories cranks are actually over stuffed right off the bat, and can see noticeable improvements just by opening the channel up...they not only pickup power, they also usually pickup runtime.........In the end the crankfiller should not get in the path of the incoming mixture...filling a void in the nose of the crank is one thing, but partially blocking the intake path with a ramp of silicone is not a good idea. IMHO.....When I fill a crank I try to make sure my ramp will make as little contact with the mixture as possible....

This season I did a test comparing filled crank vs non filled crank using the Bonito...... Judging by whats written on these forums It seems stuffing the crank on the Bonito is believed to be the single most important mod that can be done to it.......As apparently this mod brings out the bottom end of the engine........... I actually ran a non filled Bonito vs half a dozen of the filled Bonito's all season long on the track.....During the season we all swapped controllers back and forth , and even did a few drag races.......You cannot tell which Bonito is filled and which one is not...these is absolutely zero difference on the track..... not one person could tell ..... The Bonito with the non filled crank had just as much bottom end as the filled crank Bonito...and whats really strange is the non filled crank engine actually was a little better on fuel.......


Anyways here is a video of the modified Bonito that does not have a filled crank.... It has massive bottom end and has no issues with idling down....so in the the end what was said/thought/sold to be the most important modification that can be made to the Bonito ended up being quite worthless for improving its performance.....And this is not just dyno testing, this is a pile of on track testing with some pretty skilled/experienced drivers....There are dozens of modifications that can be done to a Bonito that are a thousand times more effective then putting silicone filler into its crankshaft...Now of course I have not tested every engine out there in this manner...

sorry for the long post guys, but I figured I have some good insight into this, as I did do a pretty thorough test on this during the season....cheers !

edit: in no way am I implying anyone else info is wrong or false....i am just relaying what I found with my own Bonito and several other engines I have tested..

+ YouTube Video

Maximo, were your tests of filled vs non filled all on equally modded engines? Were the tests done on stock vs stock? To me all your post says is what the putty does to YOUR modified engines. I am gona guess maybe 1% of the worldwide racing population uses YOUR racing engines. It almost seems as if your trying to discredit someone and what they said, so I sure hope your experience your speaking of is with more than just your own modified engines!!