East Bay Pete

This has been a question that most people ask the first time they see the car. The root of the design gets down to the fact that I wanted to try to keep the car as original as possible but swap the nitro for brushless. What I wanted was to keep the 2-speed...I liked the novelty behind it, but I also theorized that it might be a bit more efficient to have the lower 1st gear and higher 2nd gear. Also, I thought it might be a bit of a pain to machine an adapter for the spur gear. Lastly, if I want to change the overall gear ratio, I can do so by changing the gearing on the motor side of the setup including getting more torque. I have also run it in an "overdrive" gearing setup with a pinion 8 teeth bigger than the spur. It was that setup, along with a 6S lipo that yielded 90 MPH.

So, with the desire to keep the 2-speed transmission, that meant I had to keep the mechanical brake/servo. The problem was that the disc brake was in the way of the motor if I were to do a direct drive setup. So, the bridge was developed to move the motor forward of the disc, but then also be able to engage the existing 1st and 2nd gear spurs.

The only change (and it's a pretty big one) is that the chassis brace had to be removed and the top plate needed to be shortened in order to make room for a battery that was taller than the height of the top plate. As a result, there is going to be increased flex in the chassis. This, however, hasn't resulted in any stripped gears or pulleys, etc.

I recently had some on-track setbacks, but it seems that these were due to poor quality/low C lipos. I have now run it twice with 40C 5000 mAh Thunder Power Pro Race packs in a 4S configuration with nice results. It was a smaller 1/10 scale track (NorCal Hobbies), but the mAh per min were 339 the first time and 478 the second time. These were not full pack runs...just enough to get data on max amp draw, volts & rpms. The second run was 4:45 and I believe that was about 50% of the pack (I'm hoping for 10 min run times). With that said, I do need to go to a higher gearing for a larger track which will change these numbers quite a bit...I'll know more when I can run it on a 1/8 scale track July 12 at RAMS in Santa Clara.

Rich Browne

Well, it was another fine day at the RAMS. It was a test and tune day - the track was set up, prepared and sprayed - it was a perfect 85º with a light breeze. Plenty of track time. About thirty cars were out. I'm kinda focused on 1/8th electrics - so here's what I learned today:

Current Empire package is a M3 converted by Rick Davis to electric. Castle Creations MMM Speedo and 2650 KV motor. Castle products performed flawlessly (I love the speed control tune-ability via Net Book - easy and FAST). The battery pack is a Max Amps 4200 mah, 14.8 V. The car is designed to use 95% stock Kyosho components. That goal is met. We are currently drawing 800+mah/minute - we were hoping for 600 - 650 mah/minute. This means our run time is shy of the 5 minute mark. The good news, the damn thing is crazy fast. We'll get the details sorted and the run time up.

We have more to do - we'll keep plugging along. Here are the first photos of the Empire Rick Yoder car (designed for 158mm buggy 4C packs) - along with the Empire Rick Davis car. Enjoy!

bertran

Nice looking car, and I LOVE that everything is secure on the main chassis!!!! Will you guys try running hotter motors : ie speedpassion V10 3.5R,4.5R,5.5R....????? Also what about the new Tekin RX8 ESC coupled with Thunder Power 5000mah 4S (40C) ???? Finding the right motor/esc/battery combination to run seven to ten minutes flat out against the nitros is now possible. Your design is also way better than the other 1/8th scale conversions out there as far as battery fit and low CG is concerned, and with the aforementioned upgrades it can be unbeatable!!!!!!!!!!!!!

Rich Browne

Whew, much of what we have learned is from e1/8th off road and 1/10th electric sedan. Both of those classes are pretty extreme. Add more weight, more speed and more traction - e1/8th on-road. As a group we have a lot of 1/8th on road experience - chassis setup , tires and all that are under control - plus, we have two of the fastest drivers in the country, Jim Adkins and Scoot Kimbrow. Our home tracks are the RAMS and NorCal Hobbies - lots of electric interest/knowledge with the racing community at NorCal. In 1/8th circles - the RAMS need no introduction.

So, here is what we are going to do:

A) The Rick Davis car will run in any 5 minute qualifiers where the tracks will allow us to run - loads of track time - check the durability and push the equipment. It will be the test mule. Combinations will be reviewed for speed run time and reliability.

B) we will continue to develop our manufacturer alliances (we have been very fortunate so far - a fair amount of support)

C) Rick Yoder will ready 3 Empire eYoders. We are hoping the eYoder will allow us greater flexibility because of battery choice. ThunderPower has been terrific with the support, as has Castle Creations.

D) report to all of you our progress. Look for suggestions.

Guys, these cars are fast. So far, this stuff ain't cheap and it is taking us time to work through many details. It has taken 5 months to get to what you see here. Remember we started in e1/8th off-road to learn about LiPos and the like (geesh - we sure aren't dirt guys).

All for now....

YoDog

iTrader: (28)

I thought That I'd clarify a couple of things that Rich has mentioned about my design.
The battery pack... I've designed the battery tray to accomodate the ROAR standard 45mm X 138mm lipo footprint which all of the lipo manufactures have focused most of their development.The user can then have a wide choice of battery manufactures and reap the benefit of future battery development without changing the car.
The car has 46mm of vertical clearance that can be adjusted through spacers.

Rich calls my design the E'Yoder based on my last name but I like to call it the E'volva since the car is based on the 2005/2007 Kyosho Evolva.
Perhaps the community would like to put it to a vote?

The car is coming along and we really appreciate all of the great feedback.
I'd also like to get some feedback on which base model many of you believe would yield the most conversions, The older 03-07 Evolva or the new M3 Evolva.

John St.Amant

iTrader: (1)

I know we are talking about conversions here but I would love to see a purpose built 4WD 1/8th racer. Not a former buggy on road wanna be but a full fledged On-Road 70mph racer. There seems to be a lot of conversions for nitro off road stuff which seems to be tough and well balanced.

Some day....

Rich Browne

John, these are purpose built 1/8th scale on-road cars (Kyosho Evolva's both 07 and M3 configuration) - not off road variants - please look at the photos. One of the cars we have tested does 90 mph. We are settling on 60 mph which is reasonable.

John St.Amant

iTrader: (1)

Rich.... You have obviously misread what I wrote. I was trying to say is a new design that was built with the intention to run Li-Po's and a Brushless motor for 1/8th on road. I know full well what is going on here and a lot of you are making very cool "Conversions". Also what I had tried to state clearly that there were many "Conversions" for the so called Nitro Buggy to Brushless but they tend to have much more room for placement of components for proper balance and function. A no compromise type car. Something that optimizes drive line components because there is no longer that shock from the clutch and 2speed.
IMO the entire car needs a redo. But thats just my $0.02.

YoDog

iTrader: (28)

John, I see your point and I have been preaching for a long time about seeing a manufacturer step up and produce a ground-up 1/8 scale brushless car.
Until they see a viable market, no one is going to put forth the effort and expense of such an undertaking. Let's consider a touring car ground up design. I estimate that after the initial design, prototype development, tooling and then actual parts being assembled into a kit, not to mention packaging and marketing, it would cost about $75k minimum just to get the cars into the stores. This is why conversions are more appealing for the time being, so we can show the manufactures that there is interest and money to be made. I have no doubt that if we can start a trend that grows steadily, we will soon after see purpose built designs make their way to the market.

If any of you guys want to see that happen, please keep asking questions and buy the conversion kits as they become available. It's all about having fun but it's still a business.

John St.Amant

iTrader: (1)

For all the crap out there that people buy it makes me wonder sometimes.
But if you built it, they will come. I bet people are getting sick of clutches , nitro stink AND TUNING CARBS. Most of all.. the stink. If some one makes a good new car .. others will follow. I for one just want to race but not kill the air in trying to breath. But I'm also anal and like my cars top notch... not second nature.

DLS II

Hi, why not design a chassis with extensions on either side to hold batteries? I.E.-big enough to hold standard 45x138 lipos. I have often thought about doing it but money and access to machine tools are a problem. Don

John St.Amant

iTrader: (1)

I think I'd rather have my twin $150 bombs in a safe place where they wont get wacked by a fellow competitor.

John St.Amant

iTrader: (1)

I like your set up ! It looks like you've done a lot of work there.
But if I'm correct, that is not a roar approved pack. Or is it?

Rich Browne

We have talked about doing a third layout. Not out of the question.

First, need to resolve power issues - these cars are creating some insane loads. East Bay Pete has been gathering some scary numbers with his Eagle Tree data collection. Power management will be task #1.

After we are sure we have the power and support - then the chassis will follow - John I do agree with you - "do it right" is the only way.

Much still to e learn

DLS II

OOPS! I hadn't thought about that! I'm to used to the idea of using A123 cells. Don