.12 riggers

[gooycheese]

Hi all,

I had the chance to run my .12 blazzin this weekend, with Tom Moorehouse running his FF.12 . One question I have is why would a V937/3 prop work for his boat and not for mine, his boat ran great with this prop mine was a tail hopping mess .............lol? I also tried running a new engine (novarossi .12) engine seamed great just need to find the right prop for it, I normally would run a 215 prop on my OS CV-R engine (is it possible that I should try a smaller prop since this is considered a higher rpm engine?)( I really didn't get a chance to run the Rossi correctly since the carb I was running was an OPS .45 carb)? I am considering 2 different carbs for my Rossi engine one would be the OZ TZ carb since it is a real close running engine, and the other would be the K&B black which from what i understand is about .05 larger bore that the stock slide carb that come on the engine ( both carbs would be good carbs for me to have since I do have (.12's - 18's - and 2 K&B .21's)).

Thank You,

Paul

 

[ek kustomz]

Hey Paul,

On the 937 I would look at design differences or different sponson adjustments to get rid of the hop 1st. If none of that works the try adding some cup to it. I ran on on my boat this past weekend and it was fast but it hopped as well. The prop seems to scream just has WAYYYYY to much lift. It makes a great SAW prop though. As far as that rossi. I would say keep your props around 35-37 mm and let that thing sing.

 

[anthony_marquart]

I've never been able to get the v937 to run very well either. It you take some of the tips off it will be a little better.

 

[Tofastformellow]

Try a -ve angle of around 3 deg down on the strut , and heaps of front aoa on the sponsons , i have run v9's on the ffr and it works !!

it hops till about 1/2 throttle , then picks up.

dont worry about high aoa on the front , the back will lift enough to correct it and it will ride neutral on the sponsons and -ve on the tub .. then it wont blow off ...any faster and the front sponsons need after-planes to keep -ve pressure at the rear of the sponsons.

at least thats the way this fool see's it ..

LOL's

Jase

 

[anthony_marquart]

When I added negative strut with the V937 it made the hop worse... didn't change the sponson AOA though.

 

[AndyBrown]

The V props want to run higher. Rise your strut about .060" to .080" and set the strut at zero degrees.

If this doesn't keep the prop hooked up a little hull modification will be required.

I'm thinking about making some carbs for the .12-.15-.18 motors.

Any info on neck sizes would be appreciated.

Also pipes! What are the I.D and O.D. of the headers for the different engines you guys are running?

Good Boating!

 

[Mark Leyde]

The V props want to run higher. Rise your strut about .060" to .080" and set the strut at zero degrees.If this doesn't keep the prop hooked up a little hull modification will be required.

I'm thinking about making some carbs for the .12-.15-.18 motors.

Any info on neck sizes would be appreciated.

Also pipes! What are the I.D and O.D. of the headers for the different engines you guys are running?

Good Boating!

Andy the bored hole to accept the carb on the Picco .12's is .470"/12mm

Mark

 

[J Solinger]

I have had a tough time with the v937 too. I got it to work well in the straights but it would hop through the turns. At the end of the day I decided to stick with the x and m series props.

 

[gooycheese]

Hi Andy,

Carb Neck Size :

NR .12 - .470

OS CVR .12 - 10mm - http://www3.towerhobbies.com/cgi-bin/wti00...=LXWY01&P=Z

OS cvrm .18 - 10.9mm - http://www3.towerhobbies.com/cgi-bin/wti00...=LXGMN4&P=Z

OS TZ .12 - 12.96mm - http://www3.towerhobbies.com/cgi-bin/wti00...=LXKKU2&P=Z

OS TZ .18 - 12.96mm - http://www3.towerhobbies.com/cgi-bin/wti00...=LXJRA0&P=Z

Header :

NR .12 "Team Associated" header - ID .490 / OD .562 - http://www3.towerhobbies.com/cgi-bin/wti00...=LXBMF4&P=7

OS cvr .12 (side exhaust) "traxxas" Header - ID .443 / OD .517H x .485W - http://www3.towerhobbies.com/cgi-bin/wti00...=LXJM08&P=7

OS cvrm .18 - The same header on the OS cvr .12 fits the .18 cvrm ( haven't run the .18 cvrm yet)

Pipe :

Macs 2.5 - ID .475 / OD .563 - http://www3.towerhobbies.com/cgi-bin/wti00...LXZ557&P=ML

NR .12 Exhaust port :

ID .437 / OD .470

I hope some of this helps, I tried to measure everything I could for the little engine's I have. If you need more info please ask

Thank You ,

Paul

 

[ek kustomz]

The V props want to run higher. Rise your strut about .060" to .080" and set the strut at zero degrees.If this doesn't keep the prop hooked up a little hull modification will be required.

I'm thinking about making some carbs for the .12-.15-.18 motors.

Any info on neck sizes would be appreciated.

Also pipes! What are the I.D and O.D. of the headers for the different engines you guys are running?

Good Boating!

Now one of those pipes would look nice on My new bantam.

Zach

 

[Preston_Hall]

Do like Andy said. Zero degree strut and raise it until the hop goes away. Adjusting the sponsons won't help unless the are wrong in the first place.

 

[AndyBrown]

Thanks Paul!

I will be making some of those parts in the near future.....pipes and carbs.

I'll be back to ask for more dimensions such as neck length and stock bore on the carbs.

Good boating,

Andy

 

[ek kustomz]

how about those pipes??? I would be interested.

Zach

 

[anthony_marquart]

I'm looking forward to them too.

Thanks Paul!
I will be making some of those parts in the near future.....pipes and carbs.

I'll be back to ask for more dimensions such as neck length and stock bore on the carbs.

Good boating,

Andy

 

[Watercadet]

Andy, I am thinking it may be easier for you (and us!) if you made different spacers for the carb throats. You could have a small number of carb neck sizes (1 or 2?) and many different spacers to fit all the different case bores

I think Hardcore racing did that for the car guys and I remember them working well for me.

 

[AndyBrown]

Thanks for all of the info. guys!

With so many engines availible the carb adapter sounds like a good idea.

Are most of you using the MACS 2.5 cc pipe? I'm guessing that many of you are running them about 3" from the center of the cylinder. (front exhaust)

I assume you are butting them to the header pipe......which I'm guessing has a .470" I.D.

Are the most popular engines side exhaust or front exhaust?

 

[gooycheese]

I started with a side exhaust but that engine was the OS CVR .12 and it is more a sport engine. Most if not all the more performance engine would be rear exhaust (over the backplate). Now my pipe length on my .12 is just under 8" from cylinder center following exhaust path to the fat of the pipe. The header I am using on the NR .12 is .490 id and the pipe is .475 id ( and that is the macs 2.5 pipe & Team Associated header). I am also using a CD machine muffler. I will say this it would be really nice to have some high quality parts, if it is possible to keep the cost down that would be awesome ( i started with .12 figuring it would be cheaper) lol i was fooled a little . But I will do what I have to for quality

Thank You,

Paul

 

[anthony_marquart]

front exhaust Andy. Lots of guys do run the Macs pipe. Something better is neede on the pipe though. Glen quarles has a good one.

Thanks for all of the info. guys!
With so many engines availible the carb adapter sounds like a good idea.

Are most of you using the MACS 2.5 cc pipe? I'm guessing that many of you are running them about 3" from the center of the cylinder. (front exhaust)

I assume you are butting them to the header pipe......which I'm guessing has a .470" I.D.

Are the most popular engines side exhaust or front exhaust?

 

[Ron Olson]

Andy, I've got a NR .21 carb on my OS .12 CV-R but the bore might be a little big for most boaters. The problem has been that most carb bore sizes have been restricted by ROAR and IFMAR, we don't have those.

The sleeves would be a great idea so that you wouldn't have to mess with the various sized bores in the blocks.

Glenn's pipe works well and is really quiet on the water with the internal stinger but we're always looking for a good pipe to try out. Your .21 short pipe is close to what is needed.

Now all we need is a hot .12 engine made specifically for boats to throw some top-notch parts on (hint-hint).

 

[Mark Leyde]

Now all we need is a hot .12 engine made specifically for boats to throw some top-notch parts on (hint-hint).

I'll second that! An all out racing MAC.12 sounds good to me.