HPI R40 Nitro Car Forum

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01-14-2005, 10:47 AM

#4261

JAG Racing

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Re: Body and wind resistance?

Quote:

Originally posted by KLANDERMAN
Thanks again JAG for the tip on the first gear ratio.
We race at a parking lot, but the straight away has atleast 60 yards. the plastic gear for the first gear has 48 teeth, should I use the same gear with the gold clutchbell gear or what do you suggest?
Does the body affect the performance with the wind resistance of my R-40?
I use an HPI nissan 350z 200mm body to race, but I practice with an HPI opel vauxhall 190mm.

Does the lightweight 2 speed tranny work better in straights?

That is a good sized track! Is your engine screamin at you by the end of the straight? Keep the spurs as you have them. Changing the pinion gear has a greater impact than changing the spurs.( pinions are courser adjustments).

Body - Yes it does. Wind resistance is a good thing as it provides the downforce you need to keep the car from becoming a plane. The slope of the body lines determines where and how much down force you can get. The rear wing provides the rear downforce while the slope of the grill section and hood along with the window plays a role in front end downforce.

I think the "hot" bodies people are running now are the Mazda6, Nemesis , and Stratus. I recently bought the 200 mm Vauxhall I just havent tried it yet.

The LW 2-speed doesnt necessarily work any better in the straigths. It's benefit is it is > 20 grams lighter and this makes less work for the engine to rotate. Net result is the car can accelerate slightly better.

Good luck!

01-14-2005, 10:55 AM

#4262

KLANDERMAN

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Thanks!!! I have a race this weekend and I'm going to try on saturday all the tips you'vr given me, I'll let you know on monday how I did.

I have another question. Should I change the gear diffs to aluminum? are they going to be heavier? and if they are, should I change all the extras to graphite like for example the battery holder the shock tower front/ rear and the belt tensiones to compensate the weight? let me know ok

01-14-2005, 11:07 AM

#4263

fastharry™

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the aluminum gears wear out fast..not worth it...
Put the grahite towers on(changes the geometry),add the lightweight shafts,the .08 trans,and you'll be fine.....

01-14-2005, 01:02 PM

#4264

JAG Racing

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Quote:

Originally posted by KLANDERMAN
Thanks!!! I have a race this weekend and I'm going to try on saturday all the tips you'vr given me, I'll let you know on monday how I did.

I have another question. Should I change the gear diffs to aluminum? are they going to be heavier? and if they are, should I change all the extras to graphite like for example the battery holder the shock tower front/ rear and the belt tensiones to compensate the weight? let me know ok

Let us know how it goes!

I agree w/ FastHarry on the Al gears. BTW, where did you find the Aluminum differential gears?

You can spend a small fortune on graphite stuff and not add much benefit if your not careful.

Best purchases for reducing weight are:
"AAA" cell battery pack
lightweight shafts
lw 2-speed
chassis
spool

So you're looking at $185 to save 100 grams or so. The next item I would look into is Titanium pivot balls that AMGRacer mentioned. All it takes is money!!

I assume you are a pretty swift driver.

Last edited by JAG Racing; 01-14-2005 at 01:09 PM.

01-14-2005, 03:02 PM

#4265

KLANDERMAN

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jajajajaja! I can hold my own, but thanks for everyone's help.
The problem here in Guatemala is that I can't find anything for my cars, I either have to order from www.towerhobbies.com or www.rcmart.com in Honk Kong, so I have to be careful in what I order because it takes a few days to get here...

If you guys are looking for HPI parts, try rcmart, they have quite a few options, always cheaper than in the states...

01-14-2005, 03:22 PM

#4266

20 SMOKE

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Quote:

Originally posted by KLANDERMAN
jajajajaja! I can hold my own, but thanks for everyone's help.
The problem here in Guatemala is that I can't find anything for my cars, I either have to order from www.towerhobbies.com or www.rcmart.com in Honk Kong, so I have to be careful in what I order because it takes a few days to get here...

If you guys are looking for HPI parts, try rcmart, they have quite a few options, always cheaper than in the states...

http://shopping.rcmodel.com.hk
I found to cheaper than rcmart as for shipping

01-14-2005, 03:25 PM

#4267

KLANDERMAN

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Sorry couldn't get the link opened... maybe I'll try later...

01-14-2005, 03:27 PM

#4268

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had to take the www off

01-14-2005, 03:29 PM

#4269

KLANDERMAN

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Got it!!!! I'll check it out right now...
Thanks...

01-14-2005, 09:00 PM

#4270

HarKonnenD

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LHS is gonna get more Novarossi's in soon. I'm thinking of the NS12 instead of the RB.

01-15-2005, 07:00 PM

#4271

HarKonnenD

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Anyone have an idea how much faster my R40 will be with the .8 module gears and lighter parts alone compared to a whole stock R40? For the most part I know the car will just accelerate quicker being lighter, but as far as a top speed gain I have no idea. Time to look into real car and I'm saving for insurance. Need/want one really bad.

01-16-2005, 07:12 AM

#4272

JAG Racing

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Quote:

Originally posted by HarKonnenD
Anyone have an idea how much faster my R40 will be with the .8 module gears and lighter parts alone compared to a whole stock R40? For the most part I know the car will just accelerate quicker being lighter, but as far as a top speed gain I have no idea. Time to look into real car and I'm saving for insurance. Need/want one really bad.

Well, I havent actually tested this out but it makes sense to me that since the 0.8 gear set has a lowest 2nd gear ratio of 4.339:1 and the 1.0 gear module has a lowest 2nd gear ratio of 4.955:1 that you would have about 10 - 15% more top-end speed. I guess the next question would be how many seconds would it take to get to this speed. I'll leave that one to you...

01-16-2005, 07:24 AM

#4273

HarKonnenD

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Cool. Sounds good. I'll try that out when I get time. My stuff are gonna go up on ebay soon.

I certainly think a good $150+ is enough for some upgrades in the R40. First I'll go with the chassis, 4gear rear diff, and lightened shaft parts. .08 module gear I'll think bout last.

01-16-2005, 11:10 AM

#4274

JAG Racing

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Quote:

Originally posted by HarKonnenD
Cool. Sounds good. I'll try that out when I get time. My stuff are gonna go up on ebay soon. I certainly think a good $150+ is enough for some upgrades in the R40. First I'll go with the chassis, 4gear rear diff, and lightened shaft parts. .08 module gear I'll think bout last.

Just for curiousty, paste the URL so I can look at the 4-gear rear diff..... thanks