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Old 10-13-2001, 07:34 PM   #16
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and the third needle being? why is it so dificult to get my answer here?

wich needle is #1, #2 and #3 i dont think i get it.
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Old 11-12-2001, 12:07 PM   #17
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Ron There is no third needle. You have a three screw adjustment.
High speed, Low speed, and the third is a low speed seat. You also have a low speed idle screw but that just set your idle not mixture. The movement of the low speed seat allows you to adjust the characteristics of transistion from low speed needle to high speed needle. BTW I siezed a MT12 by try to keep up with others by leaning the low end. Keep the low end a little rich to keep your temp down in the engine. This will make idling a little tough because you will have a load up condition where you will have the motor die in about thirty seconds (or aleast tune it that way). Good idling motors will run hot. As for the guy beating you out of a corner, sydwinder is probably correct. The clutch engagement may have the other guy getting into the power band sooner than your car. I cut my clutch a little which will make it engage higher in the rpm range. The delay of clutch engagement is negligeble and the performance is greatly increased. With a centax style clutch this is adjustable with the turn of a screw in the clutch. That is the way to go. I am probably going to get one soon. Good Racing.
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Old 11-12-2001, 01:08 PM   #18
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well i answered my own question trying to draw up a picture for you guys.

here is the deal, the brass side is the "jet" its the hollow tube the fuel comes in threw, the black side is the needle. if you screw both side IN (clockwise) this leans or kills the fuel intake. i kknow this already (but not my question) so i know that turning both in is not what im wanting. im wanting the fuel mix down lower into the low end side of the powerband so what im wanting is the brass side OUT and the black "needle" side in this moves the fuel mix over to the left more wich is in the low end section more. get it?

if the brass side is set say flush and i screw the black "needle" side in 1 turn im leaning the low end (this is not what i want) its already set fine. if the black side is set (from the factory or what ever) and i screw the BRASS screw in its doing the same thing leaning out the low end (again NOT what i want)

i want the whole needle setting more into the lower end powerband of the enigne so as the slide just starts to open the spray bar is right there in the begining of the air intake section. not more in the midrange section of the engine. where its already at. i posted this because i was in a hurry to find the answer but after studing it for a while i figured out what i needed on my own

so i guess you guys no now what im after.
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Old 11-12-2001, 06:18 PM   #19
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Ron I understand what you are talking about. First lets get past the 3 needle thing. There are 4 screws on the Nova slides. Obviously 1 is the slide opening control or as we know it the idle speed screw. forget that one
The secont is the high speed mixture screw that stands up in the brass housing right.
The other two are the low speed that transitions when the slide opens and closes and the brass one on the opposite side that is fixed in the housing, the midrange.

You are suffering two issues but first I'll cover the adjustment of midrange as this seems to be one of those OOOOHHH don't touch that things for many folks.

First when starting with the Midrange spray valve flush with the case you should not need to adjust it any further than 1 turn either way. If you move the low speed and midrange the same way together (in one out the other you skew the midrange fuel mixture up or down the midrange scale. as either more or less air is rushing past the two of them at a given point VS a given setting between the two at any fixed opening.

MT 12 engines get flat when you overlean the low speed mixture. leaning the bottom end to compensate for a clutch that engages to low will kill your engine prematurely.

You need to start 3 1/4 turns open on the low end (it will probably settle around 3 or so, any less than that and it's probably lean) and about 4 1/2 on the top with the midrange flush. Adjust the top end first always. once at full temp the top end is acceptable then begin adjusting the bottom. An MTX2 takes two tanks to fully heat soak the chassis at which point a suitable low speed adjustment can be made.

Here is how to check the low end. Once it is fully warm and the high is adjusted do the 5 second Idle punch test. If you punch the throttle and there is no immediate smoke and I mean immediate the low is to lean. If it goes five feet and begins to smoke the midrange is taking over so don't let this fool you. Once you get that immediate wisp of smoke from the low end on a punch test then you can begin to progressively lean the midrange up to a full turn and watch the performance from the five foot mark on. You will see it change.

Now before you go tweeking all that stuff go get some silver mugen clutch springs and teflon shoes. Those are just tight enough. The clutch must be loosened up or no amount of carb tweeking will help off the corner punch, On a big track it becomes less evident.
better yet invest in a centax.

I run 43/47 spurs 17/20 pinions on a moderate sized track and 18/21 on a longer one.

I have a very good setup for the MTX 2 on foam tires if you want it
On the MTX2 the type of tires, clutch and down/up stop screws
are everything on a high bite technical track

What pipe do you use?

Hey Pups who screwed up your motor. DOH!!! Sorry dude I just had a bad flashback!!
What happened to that guy?? At least he quit buggin me. Sheesh
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Last edited by Motorman; 11-12-2001 at 06:25 PM.
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Old 11-12-2001, 07:21 PM   #20
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WOW Thats some awesome info Motorman....... I did not realise that the clutch settings were that critical....... I also was too scared to play with midrange, but I might give it a show now......

Do you have any "base" needle settings for the CX12? I have been messing around with mine and it seems to run OK, just like to know what your experiences on approx settings would be. I realise it relies on pipe and weather, etc, just after ballpark stuff.......
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Old 11-12-2001, 11:15 PM   #21
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i would really like to see some video of that. that is how you tune your engines? by the "punch test" method? i dont think i have ever herd of that before.

i do think my low end is a little lean because it does seem a little flat.

also yes i know the total amount of needles are 4 but i dont normaly call the idle stop screw a needle even though its part of tuning the engine it just holds the slide open so its more or less a stop screw.

also i was wrong about my car and my buddies car being the same, he is using a GT pipe im using a LONG taper picco pipe. im not sure what modle it is but it looks like a long tapper nova pipe its black and looks like a torpeedo kinda pointed at the tip. i never tried to change the pipe.

here is a link to the pipe, im using the top one. that maybe my problem. it may be a big block .15 onroad pipe not sure all i know is i had a paris turbo ring pipe and that sucker had so much bottom i couldnt keep it on the track.


Last edited by Ron; 11-13-2001 at 12:32 AM.
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Old 11-12-2001, 11:33 PM   #22
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Quote:
Originally posted by Ron
i would really like to see some video of that. that is how you tune your engines? by the "punch test" method? i dont think i have ever herd of that before.

i do think my low end is a little lean because it does seem a little flat.

also yes i know the total amount of needles are 4 but i dont normaly call the idle stop screw a needle even though its part of tuning the engine it just holds the slide open so its more or less a stop screw.

also i was wrong about my car and my buddies car being the same, he is using a GT pipe im using a LONG taper picco pipe. im not sure what modle it is but it looks like a long tapper nova pipe its black and looks like a torpeedo kinda pointed at the tip. i never tried to change the pipe.

here is a link to the pipe, im using the top one. that maybe my problem. it may be a big block .15 onroad pipe not sure all i know is i had a paris turbo ring pipe and that sucker had so much bottom i couldnt keep it on the track.

http://albums.photopoint.com/j/View?...nce=0&res=high
Ron,

Increasing the length between the pipe + manifold will result in higher bottom rpm, but less top end.

Decreasing the length between the pipe + manifold will result in less bottom end (torque) but higher top end speed.


We race with alot of 1/8th drivers, many sponsered by big manufacturers. None have ever advise to touch the mid-end, as this setting has been optimised from the factory - ie your either going to lean or richen the engine out only.

I don't think playing around with your mid-end is going to help you here. You need to play around with clutch/gearing. Do you run the centax clutch and different pipe. A Nova 51602 would be ideal for the result you want.
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Old 11-13-2001, 12:45 AM   #23
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well i know where it was i can set it back but the deal is my engine has been modified so its not stock. i opened the ports on the sleve and on the carb, the guy i race with says thats my problem is that i opened the carb intake hole about 2 thousands of an inch and he said thats why i lost all my bottom end.

i just need to mess with it a little bit.

here is what sucks, it ran awsome all summer i put a gallon of fuel threw it doing great winning a few here and there but never the less the engine was dialed all summer and i never had to touch any setting. well i ran out of fuel one weekend and had to get e quart of CRAPPY ASS odonell because it was the best thing they had. the engine has never ran right since. it started running hot since that day and i started messing with all the adjustments ever since that day. I HATE THAT FUEL i then got a new gallon of byrons and its just now starting to come around again. its still not set quite right. the bottom is whats off but not by much.

thats the second time ive tried odonell fuel and had problems with it. it ran better yesturday then it has the last few weekends with the odonell. ill try a different pipe and put the settings back where they were the first of the year.
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Old 11-13-2001, 04:48 AM   #24
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Quote:
Originally posted by Ron
well i know where it was i can set it back but the deal is my engine has been modified so its not stock. i opened the ports on the sleve and on the carb, the guy i race with says thats my problem is that i opened the carb intake hole about 2 thousands of an inch and he said thats why i lost all my bottom end.

i just need to mess with it a little bit.

here is what sucks, it ran awsome all summer i put a gallon of fuel threw it doing great winning a few here and there but never the less the engine was dialed all summer and i never had to touch any setting. well i ran out of fuel one weekend and had to get e quart of CRAPPY ASS odonell because it was the best thing they had. the engine has never ran right since. it started running hot since that day and i started messing with all the adjustments ever since that day. I HATE THAT FUEL i then got a new gallon of byrons and its just now starting to come around again. its still not set quite right. the bottom is whats off but not by much.

thats the second time ive tried odonell fuel and had problems with it. it ran better yesturday then it has the last few weekends with the odonell. ill try a different pipe and put the settings back where they were the first of the year.
Hey, Ron, I guess you know that everytime you change fuel you'll have to run in a couple of tanks before the engine works at an optimum again? Perhaps it's not the fuel... try running in a few more tanks?
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Old 11-13-2001, 10:35 AM   #25
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na i went back to byrons i had to run the odonnel because i was out and that was the only thing i could get. there was a short on fuel here in my area about the middle of the summer and no one had 20% fuel. ill remember that next season to get 2 gallons before the season starts and sit on em.

i think im gona try the paris ring pipe and put the low settings back where they were.
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Old 11-13-2001, 11:16 AM   #26
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ron; have you even looked at what we have been saying about your clutch or you have already modified it. so far each of us has stated something about the clutch and you have ignored it.
Whats up with that?
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Old 11-13-2001, 11:23 AM   #27
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that was the first thing i did. way back when i started this post the clutch is pretty tight so i know its kicking in pretty late. as long as i keep the engine wound up its ok and seems to be pretty snappy but if i go into a corner hard, hit the breaks then smash the throttle it seems to fall on its face untill it gets back up to the rpm rang it seems to like.
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Old 11-13-2001, 03:06 PM   #28
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Yes Ron that is the method I use (along with reading the plug and audible tone). I rarely take the temp gun out of the case unless the engine starts to act wierd and I use it more as a diagnostic tool to Identify internal engine problems than anything else.
If your running the stock black springs toss em and go to the thicker silver ones you will notice an immediate difference. The other alternative is to go to a torque pipe as you said you were running before. A couple of thousanths at the ports will not significantly change the engines low end nor will the carb bore. My RTO engines go from 5.5 bore to 6.2 MM bore thats like .029 or so larger. Also my cranks are altered some 35 degrees which is some .040 plus between both sides of the window. And done properly the power goes up significantly.

These pipes have common characteristics.
Torque makers (for heavier cars and higher gearing)(can get by with a tighter clutch and higher gearing) Recommended for the serpent car,GT4,V1R for novarossi based 12 engines


RC 10 gt
Paris turbo ring and copies like it
novarossi 51602
Novamega 12 ci (same as 51602)
RB X15 pipe

Rev makers or horsepower makers. (for lighter cars with lower gearing)(require a loose clutch and low gearing to perform well) Recommended for the Mugen car,HPI Racer 2,OB4 with Novarossi based 12 engines, I would also recommend these for the O.S 12 engines as they are timed for excessive torque anyway, these pipes will help them rev better on top.

Novarossi 52601
Novarossi 52603 (replacement for 601)
RB X15 outlaw (stinger is oversize)
Picco 12 pipe



First loosen the clutch. Make it engage higher, better yet get a centax. They are worth their weight in gold in my opinion. Then go to the 52601 or 603 pipe. The 603 is also the pipe packaged with the pro kits however it is in a REX package I believe.

On another note many of you have never heard of me, so I will give my standard disclaimer.

1.I will be the first to acknowlege I don't know Jack.
2.I try to call Em likes I sees Em.
3. If the info I present is worthwhile to you you are welcome.
4. If I'm full of chicken stuff I will admit it.
5. If I don't respond to an email I apologize as I get alot of mail.
6. Engine requests are slow as it is my second occupation However I will get back to those who request info, just keep pestering me.
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Last edited by Motorman; 11-13-2001 at 04:51 PM.
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Old 11-13-2001, 04:27 PM   #29
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Quote:
Originally posted by Motorman


Hey Pups who screwed up your motor. DOH!!! Sorry dude I just had a bad flashback!!
What happened to that guy?? At least he quit buggin me. Sheesh
o woah i should have read this eariler
but it was larry "litodevil" yea hes one devil a pretty dumb one
but yea im stuck with a mt12 woohoo!
but with a rotary carb argh!
its both good and bad..
good thing i can just bolt right to the rc10gt
bad thing id love to have gotten a slide carb for my nrs4
o yea i looked at parisracing site and there settings for the rotary and slide are different...
one question... how much of a difference in the settings are with the rotary carb and slide?

o yea if you can tell me a base setting it be nice also i live in the same city as one of your customers old skool II
so that would probably help BTW its crazy fast! *the engine u modded for him *

NItRO PuPS

Last edited by NItRO PuPS; 11-13-2001 at 04:29 PM.
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