HPI R40 Nitro Car Forum
06-18-2005, 04:13 PM
#7456
Originally Posted by Artificial-I
Hey guys I was wondering about the 4 bevel gear diff mod. What situations are you supposed to use this in?
http://www2.towerhobbies.com/cgi-bin...?&I=LXJLH6&P=M
http://www2.towerhobbies.com/cgi-bin...?&I=LXJLH6&P=M
06-18-2005, 04:30 PM
#7458
Thanks so much for this.
Given this, I think I was correct in assuming that I should lead the engine. It was hotter than usual that day so following the higher air temp and higher humidity, i will lean it out.
Will advice of the results when I test it this afternoon.
Thanks again. Appreciate it.
Given this, I think I was correct in assuming that I should lead the engine. It was hotter than usual that day so following the higher air temp and higher humidity, i will lean it out.
Will advice of the results when I test it this afternoon.
Thanks again. Appreciate it.
Originally Posted by Artificial-I
Here ya go:
Its sometimes a bit different than what you would think and also keep a look out for what the humidity and temperature are.
When you tune your motor and you find the sweet spot and say ok its tuned. That day, go inside and check the weather in your area and record the temp at what time and the humidity. That way the next day, month or year you can check out how it was set on whatever and compare that days humidity to the current and adjust accordling.
Or if your having trouble you can always reference it.
Its sometimes a bit different than what you would think and also keep a look out for what the humidity and temperature are.
When you tune your motor and you find the sweet spot and say ok its tuned. That day, go inside and check the weather in your area and record the temp at what time and the humidity. That way the next day, month or year you can check out how it was set on whatever and compare that days humidity to the current and adjust accordling.
Or if your having trouble you can always reference it.
06-18-2005, 04:38 PM
#7460
Originally Posted by Artificial-I
Crap, already ordered my stuff. I heard it was for high-grip as well. Ill have to check out hpiracing.co.jp they normally have good explanations of what parts are set out to do.
From http://www.hpiracing.co.jp/contents/kits/r40/opt.html - 4 bevel diff. gears which show the LSD effect which it stabilizes. Width of setting furthermore spreads by modifying oil viscosity. All the Japanese championship use parts.
Which I have really no clue what that means. Which show the LSD effect, then which is stabilizes? So something that wasnt there is now there and it now stabilizes something that wasnt even there , therefore how could it have been unstable? I dont know, then is says all japanese championship use parts. Does that mean all japanese champ drivers use this part?
If someone wants to take a crack at it , let me know.
06-18-2005, 04:45 PM
#7461
Originally Posted by Artificial-I
Here is what it says, kinda confusing:
From http://www.hpiracing.co.jp/contents/kits/r40/opt.html - 4 bevel diff. gears which show the LSD effect which it stabilizes. Width of setting furthermore spreads by modifying oil viscosity. All the Japanese championship use parts.
Which I have really no clue what that means. Which show the LSD effect, then which is stabilizes? So something that wasnt there is now there and it now stabilizes something that wasnt even there , therefore how could it have been unstable? I dont know, then is says all japanese championship use parts. Does that mean all japanese champ drivers use this part?
If someone wants to take a crack at it , let me know.
From http://www.hpiracing.co.jp/contents/kits/r40/opt.html - 4 bevel diff. gears which show the LSD effect which it stabilizes. Width of setting furthermore spreads by modifying oil viscosity. All the Japanese championship use parts.
Which I have really no clue what that means. Which show the LSD effect, then which is stabilizes? So something that wasnt there is now there and it now stabilizes something that wasnt even there , therefore how could it have been unstable? I dont know, then is says all japanese championship use parts. Does that mean all japanese champ drivers use this part?
If someone wants to take a crack at it , let me know.
06-18-2005, 06:24 PM
#7462
Well I'm trying to get my lightweight 2 speed back on the car. But I need the screws for it. I know someone on this forum had hpi to send them a replacement. How did you go about it?, and what did you ask for. Just the screws or the things that are included in the maintnence kit.
06-18-2005, 06:57 PM
#7463
Originally Posted by AMGRacer
It means it was used in the 2003 Japanese GP championship. You can use this part in all situations as I have already said. Virtually every competition GP car except the R40 comes with a 4 gear rear diff.
Other than better traction in turns, im wondering what the offset of having too much..or I guess to little limited slip action.
Last edited by Artificial-I; 06-18-2005 at 07:40 PM.
06-18-2005, 08:33 PM
#7464
Originally Posted by Artificial-I
Yeah my take on it is it makes limited slip action stronger. So ill have to lookup what increasing the rear limited slip does for handling. Im not really well schooled on limited slips on 4wd cars. I kinda want to know beforehand. Ill let you guys know.
Other than better traction in turns, im wondering what the offset of having too much..or I guess to little limited slip action.
Other than better traction in turns, im wondering what the offset of having too much..or I guess to little limited slip action.
The 4 gear conversion for the rear diff increases the total surface area of diff gears moving against other diff gears which increases mechanical friction making the diff stiffer. Also since there is more surface area of planetary gears the effect of a given weight of silicone lube is greater than if you only had 2 planetary gears.
06-19-2005, 03:51 PM
#7465
Originally Posted by AMGRacer
Increasing the stiffness of the rear diff makes the car apply power better to the ground in a corner and also even in a straight line. A stiffer rear diff makes the car corner better under power but lose some off power turnin.
The 4 gear conversion for the rear diff increases the total surface area of diff gears moving against other diff gears which increases mechanical friction making the diff stiffer. Also since there is more surface area of planetary gears the effect of a given weight of silicone lube is greater than if you only had 2 planetary gears.
The 4 gear conversion for the rear diff increases the total surface area of diff gears moving against other diff gears which increases mechanical friction making the diff stiffer. Also since there is more surface area of planetary gears the effect of a given weight of silicone lube is greater than if you only had 2 planetary gears.
06-19-2005, 10:54 PM
#7466
Set-up assistance
Guys, need assistance on set-up.
What droop do you guys use in front and in the rear?
I was trying to place 5 droop in the rear. however, when i trued my tires o about 65, the ride height was so low.
With the front, i have the anti-roll bars in place. however, the droop on the right arm is always higher than the droop on the left arm.
Suggestions please.
What droop do you guys use in front and in the rear?
I was trying to place 5 droop in the rear. however, when i trued my tires o about 65, the ride height was so low.
With the front, i have the anti-roll bars in place. however, the droop on the right arm is always higher than the droop on the left arm.
Suggestions please.
06-20-2005, 02:37 AM
#7467
Originally Posted by Artificial-I
That makes sense. Thanks. Now the question is how much of a difference will it be. Also is it the same as basically running a thicker weight? Im guessing there is some difference than being just a stiffer diff.
06-20-2005, 05:57 AM
#7469
Probally. I know you can run a yellow1st-red2nd. Try it and see.
06-20-2005, 06:00 AM
#7470
Originally Posted by WeatherB
Anyone know whether it is possible to run a purple first gear pinion and a green second gear pinion together?