JFuel11

iTrader: (152)

Ok,

Looking for ideas and opinions...

A. Is it better to run heavy clutch setup such as 1.0 or 1.1 springs with a big block say .24/.27/.28 engine?

B. Is it better to run heavy clutch bell and leverage the TQ of the engine or step down a tooth or two and let the engine rev up?

C. What pipes are you finding to work well on say an OS 28 for dirt oval?

D. Do you want to set up pipe/plug and gearing to maximize Torque and gear up so you get incredible pull off the corner and let the gearing carry you down the straight or set up pipe/plug and gearing to allow engine to rev and have the rpm carry you down the straight?

Fire Away Guys, lets hear the thoughts...

Thanks

JFuel11

iTrader: (152)

I recently started running a big block engine Sirio .27 DO engine over my Sirio .21 engine and have been experimenting with the two following setups...

1. I ran full shims in the head with very hot plug, mid to high rpm range pipe and ran a 19 tooth clutch-bell (I know track size play huge roll in actually bell being ran...) Performance was good, however with the higher rpm, fuel economy seemed to suffer and big blocks tend to run out of RPM quickly so it seemed difficult to find the happy medium...

2. I ran 1 head shim less with medium plug, High Torque pipe and a 20 tooth clutch bell, Pull off the corner was strong, however if the car loaded up with any mud or track got really loamy you can get excessive clutch slip with 1.1 spring but fuel milage was much better...

Keep in mind this is more high bite track often running foam tires...

Penny for your thoughts...

youwish16

iTrader: (21)

what i would do with a motor would depend on the track surface and what tires are aloud. its all about getting the power to the ground.

i run a 3 show clutch setup, 1.0 springs with a grp .21 5 port and it works pretty well. not to much power coming off the corner but still has decent top end and fuel mileage.

just my .02 but im still pretty new to this dirt oval stuff

psychoracing

i run a go-engine .25 with the go-springs and shoes.. why a 25 u get both worlds..

diesel32x

iTrader: (7)

Just remember, If you have to much power, that will actually hurt you.

JFuel11

iTrader: (152)

I could not agree more on having too much power...

The two local tracks I race at are completely different animals in the fact that one of them is very slick no matter how much water you get on the track and you can win all day long with a good .21 engine because you cannot put the power down.

The second track I race at you can also win with a .21 and be very fast, but sometime the track comes in really well and we switch to a foam tire setup. In these instances it becomes much harder to keep up with a .25 or .28 with a .21 because you can get the power down to the ground...

On any given day a slightly underpowered car will usually run faster and more consistent lap times if it can keep it's corner speed up and run smooth... Rather than an overpowered car that will be easier to overshoot corners and kill the tires off the corner...

psychoracing

i tryed a 21 it was not anuff coming off the corner like the 25 but on a loose dirt track the 21 might be ok...

diesel32x

iTrader: (7)

I run a 21. Alot of it has to do with a good setup.

psychoracing

i can see it in llm but i run outlaw late model..

GMartinez

iTrader: (91)

I would look into this
http://www.teampicco.com/index.php?o...135&Itemid=444

THE PHILLY JYNX

iTrader: (12)

For optimum torque and power delivery depending on track surface and conditions in a .21 or larger.You might want to give one of these a try in 38mm. I'm not a dirt oval guy but what i can tell you is one of the winners of the DODC National Points series in the last couple years runs this clutch

pancanman

iTrader: (2)

i picked up a losi l8eight model and am on a limited budget to get this car ready for next weekends race. i have to get tires and a motor. our LHS a Hobby Town USA has a dynomite .21 on sale for $109.99. the guy i bought the car from had this exact motor in the car. i have known this guy for 25+ years and have raced everything from dirt mini stocks to dirt modifieds now short course and 8th scale lm and sprints. he ran very well with the dynomite .21 motor. with this car he won 3 of the 7 raceses he ran with it last season. his set-ups being the key. he has offered to help me keep it dialed in this year.

what i am wanting to know is if i run this motor 25 race nites am i going to have the same power at nite 25 or 30 as i do from nite 1. i know that a hard question to answer, with maintnance and just the overall differance from motor to motor. on average (i guess) is this a tough reliable lil motor for the money.

latemodel13

iTrader: (101)

It would be alot to ask to get 25 races with one engine. If your going to have a chance you had better be good at tuning it and keep clean oiled filters on it.

Mr. Twister

iTrader: (4)

Here are my thoughts on your question's and I hope they help.

The OS .28...The most amazing oval motor i have ever ran. Very versatile engine and will pull whatever gear selection you throw at it. Extremly usable bottom end power, brutal but thats where IMO makes it the best motor for DO if your allowed to run modded or big motors.

My setup when running the OS, My track, med to high grip, depending on the time of day, Stalker 09 body, not the SS. Intruder LOSI CF Chassis, with all the work i have done the car weighs in at a tic over 5LB. Ofna Flywheel when runningf the 28, 3 shoe, all alum shoes (Mugen Hard) 1-.09 and 2- 1.0 I run a 50 spur, and HPI 19 to 20 bell.

I have found, IMO it is best to make THIS motor labor, what i mean by that is, kepp the motor in the lower rpm range of its powerband, this thing begs to turn RPM, and that in itself makes it bottom end shine. It jerks the car when the clutch engages center off, now, the topend on this motor will make you crap your pants lol, it is no joke.

Going down in teeth on this motor i have found just is to much, again, labor the motor some and it will rip out of the corners, this motor shines on any size track, 220 to 300 ft drivelines, it will run them all. .21s will give you a wider range of tuning with cluch and bell count. The OS is very tight ration selective..IMO, one or two teeth up or down and it will do it's job and ask for more. Well bud i hope that helps some if i can help with anything else i would be glad to help.

Miketuck12

iTrader: (1)

What would be a great motor for the OFNA Hyper Sprint? I have blew the Macstar .28 engine that came with it. Blew a hole in the top of the piston (I am very new to the nitro rc world), but on the other hand I am gaining tons of experience. I did not like the Settings and adjustments on the Macstar .28. I just want to know what would be a good replacement motor for it. One that does not take a whole bunch of time tinkering to get it running correctly, and one that will hold up.