Ultimate Urban RC10GT ...

[elburro]

This is New York. We have concrete and black top ... lots of it. Where I run, its an abandoned airport with miles and miles of really wide, concrete runways. It used to be THE airport before they built JFK.

Anyway, I find myself running on concrete exclusively and since I just rebuilt my GT, and may have to replace the engine, I want to take this opportunity make it as urban as possible.

It currently has the following ...

1. OS .12CV <--- This engine might be on its way out very soon.
2. 18T Clutch Bell/66T Spur gear with the orginal clutch.
3. Brand new Stealth tranny.
4. Street tires ... see pics in my gallery.

I got questions...

* How should the gearing be setup? I figure if I dont want to sacrafice a lot of top or bottom end then maybe somewhere in the middle? I might already be okay with the gearing I have. I dunno. Help!

* What engine? Remember, this truck will never see dirt or grass ever again. This is strickly a street machine. I remember the original AE .15 the truck came with. Man, when this engine wasn't busy being a tempermental headache it was F A S T. A true power house the 30% of the time it actually ran. The other 70 % sucked. Anyway, I think a high RPM, good HP .15 might be a good thing at this point. I had the OS .15CV in another truck and had trouble getting it to hold a tune. I dunno if mine was defective or the engine is just a problem. Anyway please feel free to recommend an engine to suit my urban purposes.

* Should I bother with center of gravity? Maybe lower the truck a little? Though this will be run exclusively on concrete, it will however have to deal with cracks, manhole covers, jumps and the occasional rock. I would lower it a little but not much. I was also thinking of moving the bump pack from the extreme rear of the truck to somewhere farther up front.

Okay everybody!! Suggest stuff!!! Engines!! Gears!!! I wanna run the truck next weekend so I got a solid week to change out the engine and gears and maybe do some mods.

EB

EDIT: Please can someone give me the definitive jammy on what shocks and springs I'll need? I havent gotten straight info on this yet.

 

[specter]

I've seen pictures of your truck on www.Rcnitroreview.com (its a small world).

 

[Nitroaddict]

elburro - first, the setup u have now is almost perfect. I would stick to the factory stock gearing now, but when u upgrade to a more powerful powerplant, got up 2 teeth on the pinion gear. this will raise your top end alot and u wont notice the decrease of low end, because the new engine will more than make up for it. For onroad without alot of rough terrain, you want to keep it low, but not too low, about where u are now is perfect. i would however put the 'red' springs all the way around. this will stiffen it up a bit, and reduce the amount of body roll u have in the corners.

engine - i would recommend only one engine to you. The OS Max .15CV-R or CV-RX if u want a pull start. This engine is awesome. It produces the power of exactly 2 OS Max .12 CV engines that u are running now, but with jkust as much die hard reliability. You can get this engine anywhere for about 120-150 bucks. I use this engine, as does Christian, imbroken, and MCvickj.

Finally - check out FastEddy's gallery, he races dirt oval with his losi's and has them all set up real low. u can see his setups in his gallery, and PM him for more info and help. Sorry for the long post, hope I've been some help.

 

[elburro]

Originally posted by specter
I've seen pictures of your truck on www.Rcnitroreview.com (its a small world).

Those are really old!!

Originally posted by Nitroaddict
elburro - first, the setup u have now is almost perfect. I would stick to the factory stock gearing now, but when u upgrade to a more powerful powerplant, got up 2 teeth on the pinion gear. this will raise your top end alot and u wont notice the decrease of low end, because the new engine will more than make up for it. For onroad without alot of rough terrain, you want to keep it low, but not too low, about where u are now is perfect. i would however put the 'red' springs all the way around. this will stiffen it up a bit, and reduce the amount of body roll u have in the corners.

engine - i would recommend only one engine to you. The OS Max .15CV-R or CV-RX if u want a pull start. This engine is awesome. It produces the power of exactly 2 OS Max .12 CV engines that u are running now, but with jkust as much die hard reliability. You can get this engine anywhere for about 120-150 bucks. I use this engine, as does Christian, imbroken, and MCvickj.

Finally - check out FastEddy's gallery, he races dirt oval with his losi's and has them all set up real low. u can see his setups in his gallery, and PM him for more info and help. Sorry for the long post, hope I've been some help.

Definitely. I took a look at Eddy's lowered Losi and thats basically what I wanna do only not quite THAT low. Also, the stock gearing was a 16T clutch bell with 66T spur gear. This already tweo teeth up from stock. Do they even make a 20T (I'll check).

EB

 

[Nitroaddict]

elburro - the largest pinion gear made by AE is 18teeth. Don gear it too high with that CVR though or it will be going so fast it will become uncontrollable.

 

[elburro]

Okay ... progress report ...18T clutch bell is the highest number of teeth I can find. I currently have one installed. I curtrently have 18T/66T Clutch bell/Spur Gear. I might not have to change the gearing. I also confirmed that the .15 CV-R comes in s short-crank (S) version for Associated vehicles and my LHS has one for $110.00 which I intend to snatch up over the weekend.

EB

 

[Nitroaddict]

hey - elburro - what starter box are u using?

 

[FastEddy]

Things you must do to create your monster....

Lower it! The lower the better the CG is one of the most important factors in getting it to handle properly on the street.

You can use internal .Shock down stops or get shorter shafts. Use fairly heavy springs and oil.

You will want to get 0 Degree rear suspension mounts Bottom of page Increases tire life as well as straight-away speeds.

The front hub carriers are 20 degrees stock. This is designed for off road racing so the edges of the front wheels will dig into the dirt. When you turn your front wheels from side to side you will see how the center of the tires don't make contact with the ground. When you use street tires this gets even worse. Only about 20% of the tire will contact the road during a tight turn. To fix this you need this part from AE 6211 Front Block Carrier, 5° caster. (Special Order)

To get any kind of top speed you will need to go LARGE on your bell. I use a 24T AE part 8904 24T, 32 Pitch Clutch Bell, steel and 66 on the spurr.

All these parts combined will run 25-30.00 CHEEP...

This will put you on your way to creating your street racer.

 

[elburro]

Originally posted by Nitroaddict
hey - elburro - what starter box are u using?

My current starter box doesn't have a name on it. It's a red and the motor is so big it sticks out the side of the box. Lots of torque and hasn't burnt out like that cheap OFNA one I had. I Used to have it set up to start HPI trucks cuz I had one. I repositioned the motor and I use it to start my RC10GTs now. Why do you ask?

EB

Originally posted by FastEddy
Things you must do to create your monster....

Lower it! The lower the better the CG is one of the most important factors in getting it to handle properly on the street.

You can use internal .Shock down stops or get shorter shafts. Use fairly heavy springs and oil.

You will want to get 0 Degree rear suspension mounts Bottom of page Increases tire life as well as straight-away speeds.

The front hub carriers are 20 degrees stock. This is designed for off road racing so the edges of the front wheels will dig into the dirt. When you turn your front wheels from side to side you will see how the center of the tires don't make contact with the ground. When you use street tires this gets even worse. Only about 20% of the tire will contact the road during a tight turn. To fix this you need this part from AE 6211 Front Block Carrier, 5° caster. (Special Order)

To get any kind of top speed you will need to go LARGE on your bell. I use a 24T AE part 8904 24T, 32 Pitch Clutch Bell, steel and 66 on the spurr.

All these parts combined will run 25-30.00 CHEEP...

This will put you on your way to creating your street racer.

Okay, heres the stuff I don't undertsand ... shock down stops. If these are supposed to stop the shock from compressing too far, then how does that help me lower the COG? I would think that there needs to be a physically shorter shock. I'm cool with the 5 degree hub carriers and the zero degree rear suspension mounts.

EB

 

[elburro]

UPDATE:

Okay, I was in a rush before but I did manage to get a look at my starter box on the way out of the house this morning. It has no markings other than a sticker that says "SUPER STARTER Racing Product". Has a motorcycle battery in it and banana plugs on the side for charging.

BASH TEST:

I took the truck-in-question to Floyd Bennet Field yesterday (last day of my vacation ... cry for me), to really test it. I ran the truck on my street a little but really hadn't put it to any abuse. So I started it up, and ran a few tanks. Remember, all I did was move my old truck to a new chassis with the exception of a rebuilt transmission. Other then the tranny, and what its bolted on to, this is the same old truck. Same old engine and everything.

The truck was way faster than I remember it being and the engine is running great depite the yellow goop (unbruned fuel) it leaks constantly. I can only attribute the speed to the rebuilt tranny. Its the only thing that changed. Anyway the truck is a beast right now with a .12 CV in it. That .15 CV-R is gonna be a rocket.

At higher speeds, it became increasingly obvious that the truck's COG is too high and it doesn't get enough front-end grip on the road. It seems to want to slide out of a turn nose first. The wheels in the rear might not be getting enough bite on the road either. THis is the first time I ever tried to analyze the suspension on an RC vehicle (or any vehicle for that matter).

Eddy is definitely right. This thing needs to be low and stiff and it needs the most possible tire surface metting the road at all times. I'll order the parts today. Thanks Eddy!!

EB

 

[FastEddy]

A down stop keeps the shock from opening all the way. This makes the shock shorter thus lowering the unit.

Putting the spacers inside the shock in the shaft will do this.
measure the amount of spacers needed by pushing down on the truck to the desired height then marking the shaft with a marker at the bottom of the body. When you let go and extend the shock you will get an idea of the number of spacers to use.

Its cheep to do, just make sure you get plenty of spacers.

 

[elburro]

Originally posted by FastEddy
A down stop keeps the shock from opening all the way. This makes the shock shorter thus lowering the unit.

Putting the spacers inside the shock in the shaft will do this.
measure the amount of spacers needed by pushing down on the truck to the desired height then marking the shaft with a marker at the bottom of the body. When you let go and extend the shock you will get an idea of the number of spacers to use.

Its cheep to do, just make sure you get plenty of spacers.

FastEddy rocks the freakin' hauze!!

The 5 degree castor blocks are on the way (AE 6211) (Dave at CR Racing had one set), and I am going to custom make the shock stops from plastic tubing (not fuel tubing). I have all kinds of springs lying around so I'll experiment (first with red all around). Gonna paint me another lid too. Something more on-roadish.

More questions:

1. What about tires? Foams? Yours look like foams. Where do ya get em in our size?

2. Do I put the spacers into the shocks BEFORE or AFTER I do the oil bubble thing? I only built shocks one time.

EB

 

[elburro]

UPDATE:

Heres is a the lowered truck. I am still waiting for the 5 degree caster blocks to arrive. Engine goes in next week.

EB

 

[FastEddy]

Its starting to look like a real truck :bow:

Trash the rubber tires but keep the wheels to aid in the alignment of the front ad rear of the truck.

First get foam tires. 15.00 a set including wheels. check around and you will find some.

Mount the wheels only, front and rear. With the radio on and the wheels pointing forward and trim tabs set to 0. Adjust your camber so both the inside and outside edges on the wheel touch the table. you need an even flat place to do this. bounce the truck several times after doing this to make sure you didn't get a false setting. Do the same on the rear.

Take a strait edge I use a .5 x .5 wood strip, and place it across the front of the truck on the table. It should be long enough to go from the outside edges of both wheels and a bit longer. Adjust your toe settings until all 4 rim beads are touching the strait edge at the same time. Now you are set to 0 toe. You will need to play around with the toe settings a bit but I like just a tad bit of toe in. To get this adjust the the inside edges of the wheels to be about 1mm away from the strait edge on both sides. This will give you about 1-2 degrees of tow in. Doing this will help you go in a strait line. Don't forget to bounce the truck several times during the process to avoid false settings.

Now that you have the maximum amount of tire surface touching the ground and the are aligned to go strait, try a road test. I think you will be ready to get dialed in at this point. Please refer to your bouncing GT thread for a few more tips.

Taking an RC and making it do things its not designed to do is when this hobby starts getting fun. :LoL:

 

[elburro]

TODAY'S UPDATE:

The 5 degree caster blocks arrived yesterday and I installed them last night (didn't lose even one e-clip!!). Theres now a whole lot more tire on the ground then there used to be. Camber has been adjusted and the front wheels have a slight toe IN. Next I want to address the rear wheels. They have zero degree suspension mounts but are noticably toed IN and they have a slight camber. I could prolly get another 15% of that tire surface onto the ground with camber adjustments.

Heres the bad news. I screwed up cutting down the springs. I'll need new ones to try again. Gonna wait till I get paid this week.

EB

 

[FastEddy]

How did you mess up the springs?
If you cut them a bit to short thats OK, just make sure they are the same length. Use some clips to regulate the ride height. With on road your suspension travel is minimal and you wont need much spring to work properly. Try some spacers before you purchase new ones.

 

[elburro]

Originally posted by FastEddy
How did you mess up the springs?
If you cut them a bit to short thats OK, just make sure they are the same length. Use some clips to regulate the ride height. With on road your suspension travel is minimal and you wont need much spring to work properly. Try some spacers before you purchase new ones.

I cut em too short. So short that the truck isn't suspended. I didnt have the shoch fully extended when I cut the spring. I ruined em good. It would take like 4 spacers to get it back. I think they are all different sizes too.

EB

 

[FastEddy]

pps: I guess thats how we learn.
Loving those 5 degree caster blocks are you?

 

[elburro]

Originally posted by FastEddy
pps: I guess thats how we learn.
Loving those 5 degree caster blocks are you?

I dunno how much I love them as I have not driven the truck yet since I Installed them.

 

[elburro]

ROAD TEST UPDATE:

Introduction: This truck is an Associated RC10GT with the following modifications and equipment...

* 5 Degree front caster blocks.
* Zero degree rear suspension mounts.
* HPI V-Groove tires (not M compound).
* O.S. .12 CV
* Brand new servo saver mechanism (no more crunchy steering!)
* All shock absorbers shortened by 1/2 inch.
* Associated red springs front and rear (not modified or cut).


Front End: Much less bouncy but could use a little more traction. I had a couple of occasions where the front end couldn't maintain a grip and the truck slid off the inteded path.

Rear End: Truck now spins out while turning at the drop of a hat.

Overall, this is better than last week. The truck was easier to control at WOT but now where I Want it to be. I think it still needs mushier suspension all around. Why did I get red springs? It was all the LHS had that day.

EB