PBR Allstar's dirt oval thread! UPDATE!

[PBR Allstar]

Okay, I know there are a lot of dirt ovalphiles on here so I thought I'd share some recent builds from the shop bench. The local track I race dirt oval at recently added a sportsman modified class, pretty basic rules: unmodified buggy chassis with centered battery, 13.5 or 27 turn motor, edm body, rubber street trac tires. I threw some part on a team car (all other cars in the class are B4) last week to run with a well seasoned 27T putnam motor and an SMC 4100 lipo. After a couple spring changes and not much work on the car between rounds due to some issues with my custom works car I was able to wheel the thing for TQ and the A main win. The car worked really well, could drive in good on power, a little understeer from the center off but I think that was due in part to having a bit too much cross in the car and not quite enough caster (I was running 10's across, I think 15's or 20's, maybe a split would help get some drive to the RR in the middle of the corner) in the front. Anyway, thought I'd share a pic of the team car (the black one) and the second car I just put together which is a C stamp CE car with a gold pan, I mainly put the second one together because all the old timers at the track said "that's not an RC10, the RC10's had gold tubs" so just to show them up I'll beat them with a "gold tub" next week.

Both cars are set up almost the same

27T putman motors
4100 SMC lipos
LRP Q3 esc's
Custom works Street track tires hard foam front and rear on custom works 2.0 wheels
Custom works rear hub carriers
0 degree rear arm mounts
GT servo savers
.56 front shocks w/#2 pistons and 30wt oil 4lb Lf spring 6lb Rf spring
.71 rear shocks w/#1 pistons and 45wt oil 7lb Lr spring 7lb Rr spring
RPM rear body mounts
NDRB (orange) and CDK (black) bodies

[Charlie don't surf]

Very nice, how bout' some body off pics??, I have a new Graphite team car oval build going just like I started racing with when I was 13--

[wyldbill]

wow thoes look like the hard to find custom works grey/silver wheels. i always liked nick's bodies to bad he dosent live in shillington any more, it was great to just go to his house and have a body painted,stickered,trimmed and mounted on the car all at one shot for a decent price.

[PBR Allstar]

hey CDS, I snaped some body off pics for you and whoever else is interested. the bumper mount on the gold car is a piece of stainless plate, I have another one for the black car but I just haven't gotten around to installing it and making a bumper and a new nose wing which I think will really help that car. I also took a pic to show the custom works rear hub carrier and wheel spacer, you can also see in that pic where I put the stock rear A-arm in the mill to give some wheel clearance (I didn't have to do this on the black car with the RPM rear arms. Anyway, Enjoy! -Ford.

[wyldbill]

i like that nose wing mount, here's mine it's also orange but it's a terminator.

[Bent]

Verry nice looking cars. I too have a dirt oval and like usual as soon as I think I have it right I have to completely redo the whole set up. I am really glad that you posted the suspension specs. I was wondering though if you had a picture of the track where you run these? Or maybe some specs on it. Hope you enjoy yours as much as I do mine.

[PBR Allstar]

http://www.youtube.com/watch?v=qRSOiZo3AcA

here's the track, this is the 1/10 expert sprint from last week. about 100' driveline, 10 degree bank very high bite adobe clay.

[Bent]

Wow that is a little track. Here is one of the tracks I have and will start racing again. So every one seems to get a kik out of you running a 18ish year old car ehh. I did to when I went to Wil Bills for a little test and tune. Or practice as I call it.

[AscotConversion]

Not surprised your car was fast. I remember a post by Todd Putnam on dirtoval.com saying that the newer cars (b2, b3, etc) adopted some design elements that helped for offroad, but hindered the cars on oval. The RC10 may actually be the car to beat!

[PBR Allstar]

Okay, here's the vid from last night,,, the third car in the mix (B3 with a 13.5) didn't make it to the A main, so it was only my cars in the feature... I was driving my orange car which was down a bit on power all night, my friend Ron is driving my black car.

http://www.youtube.com/watch?v=I7GbQu9GPSQ


And I changed the name of my thread so I can just put all my D.O. stuff here.

[markt311]

It's nice to have a place for dirt oval stuff.

My question is: I just picked up a Dual Sport and I was thinking about making it a dirt oval car, What class would it convert to the best? They run bombers and Sprint cars mostly right now, they're trying to get a latemodel class going but I don't want to have the only one out there. Bombers they want your car to be truck based and they limit the tires to street tires, I'm not real keen on that class cause they are always really loose. How would it do as a sprint car?

Here's a video of the track I would be running on

http://www.youtube.com/watch?v=tJtoZGAOazA

[Bent]

Ok PBR when I asked about the rules I was told you can run what ever as long as it is no faster than a 12t. So kinda open i know but we only get 1 day where the offroad guys get 6. and that includes practice. I dont know exactly how big the oval is but the site says and I quote "The overall track area is 140 ft. long by 84 ft. wide." Now the oval is a tad shorter and half as wide. Thats the best I can give you. Now the one in the picture above is 70ft straights and about 8 foot wide.

[PBR Allstar]

It's nice to have a place for dirt oval stuff.

My question is: I just picked up a Dual Sport and I was thinking about making it a dirt oval car, What class would it convert to the best? They run bombers and Sprint cars mostly right now, they're trying to get a latemodel class going but I don't want to have the only one out there. Bombers they want your car to be truck based and they limit the tires to street tires, I'm not real keen on that class cause they are always really loose. How would it do as a sprint car?

Here's a video of the track I would be running on

http://www.youtube.com/watch?v=tJtoZGAOazA

Mark,
There's not much you can do with a dual sport on dirt oval, I've tried it, so have lots of others. Some tracks used to run street stock or bomber classes based on DS's and that was okay when all the cars are the same.
The track looks like a real deal track so my guess is when they do get a latemodel class going it's going to be filled with purpose built dirt oval cars like custom works and terminator based cars, and to be honest Something RC10 chassis based wont stand a chance.
The truck based bombers are fun, and trucks can be a bit finicky on setup, but there are plenty of ways to tighten one up and fix the oversteer condition. If you're on a budget this is definitely the class I would look to running.

The cars in my posts above were built to get an entry level/budget class going, and there are several cars being built right now by people at the track I run at so it should get rolling along pretty well. I still plan to race my sprints and latemodels in the expert classes, but I want to see my son move up from the 18th scale stuff soon and thought something like this would be a good class. the rules will still allow older cars to be competitive, it will give people that have rtr 2wd buggies a place to race them with minimal modifications, and for some of us seasoned racers it will be a nice relaxing class to run in. I'm also putting together a B3 for the class as well and should have some pics of it posted in a few days.

[PBR Allstar]

Bent,


Okay, for the big track that it sounds like is part of an off road track, I'm going to assume it's prepped like an off road track? If that's the case you need to be running off road tires on the car, probably start with ribs up front and whatever the popular off road tire is in the rear, probably something like holeshots. I saw in some of your pics that you had receiver and speedo mounted to the shock tower and back on the tranny brace, get that stuff off of there quick, and get it as far forward as you can. As well, get the servo mounted as far forward as you can and move the battery box as far forward as you can (I'm able to redrill my chassis and move the battery box about 3/8" forward with a standard size servo in the stock location). On a good day a buggy based oval car is going to be 60% rear weight and that does little for making the front end work.


As far as setup and how to tune it, that is really dependant on the track. On a buggy it's kinda tough, you want to run as low of a cross number as possible without having it lift the LR tire in the turns. when I go to the track I usually use a 1 lb difference in spring split to the left and right (stiffer on the right side), and 20% thicker oil on the RF shock than I'm using on the LF. I'll set the car at 49% cross, and I'll do almost all my tuning on the right side spring collars. Electronics are set up pretty standard, sometimes if the track is really hooked I'll run a little more drag brake to get it to turn in. It's also important to get all the bumpsteer out of the car, that will mess with you forever and make other changes not work like they're supposed to.


Now remember, all this info is what I used, and what works for me at the tracks I run buggy based oval cars at. You didn't really give me any info on what you're car is doing, what you like about it, and what you want it to do better. If you want some better detailed pointers break down how your car is handling for me, how it gets into the corner, how it rolls the center and how it is coming off, as well as how much throttle you have in it at all those points. Let me know what other people are running and what the track surface and prep is like.

[Bent]

Ok as you said the big track is a part of the offroad track. Now I havnt had a chance to run my buggy there but on the little track with the grooved foams it is loose on exit and good the rest of the way in and center feels good, atleast up high. Now one thing I knoticed on the red surfaced track that is pictured is that the car would spin out to the inside as soon as it got to full throttle. Meanning when I nailed it in the straight it would spin. As far as the electronics I have a fresh picture in my post under the buggy section here. I dont know where else I can mount them that is why they are where they are.