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Old 05-24-2016, 09:30 AM   #241
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The fastest 1/8 GT I seen on 6s was a GTP2E that went 147 mph. You will most likely need at least 7s for 150+ mph. I have gone 149 mph on 7s with my Mugen MGT7.
Ok, I got a couple of questions for you. I don't want you to give away all your secrets, but when you made your 7s 149mph run, what was your theoretical top speed? By that I mean, how fast was it supposed to go on paper. I'd like to see what type of drag/friction loss you experienced. Second, what body are you running?

My car runs the same diff gears as the GTP2e, 44/14 (3.14/1), which is one of the reasons I chose this kit. The MGT7 runs a 42/12 (3.5/1), or the "overdrive" gear set 44/13 (3.38/1). So, all things being equal, the GTP2e will go faster.

In my opinion, it's all about managing friction, which is another area the OFNA has an advantage. Having the ability to dial out almost all the rear toe-in, is a big advantage. You need a little toe-in to compensate for tire drag and add stability, but not the amount most cars come with come with.

What do you think?
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Old 05-24-2016, 12:03 PM   #242
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Ok, I got a couple of questions for you. I don't want you to give away all your secrets, but when you made your 7s149mph run, what was your theoretical top speed? By that I mean, how fast was it supposed to go on paper. I'd like to see what type of drag/friction loss you experienced. Second, what body are you running?

My car runs the same diff gears as the GTP2e, 44/14 (3.14/1), which is one of the reasons I chose this kit. The MGT7 runs a 42/12 (3.5/1), or the "overdrive" gear set 44/13 (3.38/1). So, all things being equal, the GTP2e will go faster.

In my opinion, it's all about managing friction, which is another area the OFNA has an advantage. Having the ability to dial out almost all the rear toe-in, is a big advantage. You need a little toe-in to compensate for tire drag and add stability, but not the amount most cars come with come with.

What do you think?
I dont use speed calculators because they seem to usually be very innacurate. I believe my mugen went 137 on 6s that day and 149 on 7s. I run Ipanema Warrior bodies.

To me, the internal diff ratio of a car is not that big of a deal when you can just gear up the pinion or gear down the spur to compensate. My Mugen MGT7's high 3.38 internal diff ratio has never held me back.

Check out some of my speed runs:

https://www.youtube.com/channel/UCLg...zCRTPqUsSUrdPg
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Old 05-24-2016, 01:19 PM   #243
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I dont use speed calculators because they seem to usually be very innacurate. I believe my mugen went 137 on 6s that day and 149 on 7s. I run Ipanema Warrior bodies.

To me, the internal diff ratio of a car is not that big of a deal when you can just gear up the pinion or gear down the spur to compensate. My Mugen MGT7's high 3.38 internal diff ratio has never held me back.

Check out some of my speed runs:

https://www.youtube.com/channel/UCLg...zCRTPqUsSUrdPg
I agree that the gearing/speed calculators are inaccurate, but thats because they don't account for things like drivetrain friction or aero drag. But, if you know this they can be useful.

While it is true that you can match the final drive ratio by changing the pinion/spur ratio, there is a small problem with that. For example, all things being equal, the Mugen would need to be geared at 41/40 (pinion/spur) to match the final drive ratio of the OFNA at 38/40 (pinion/spur). This gives the OFNA a much greater mechanical advantage at the motor that is not lost at the diff.

Just food for thought.

I like your videos. That's super fast on city streets though.
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Old 05-24-2016, 01:59 PM   #244
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I agree that the gearing/speed calculators are inaccurate, but thats because they don't account for things like drivetrain friction or aero drag. But, if you know this they can be useful.

While it is true that you can match the final drive ratio by changing the pinion/spur ratio, there is a small problem with that. For example, all things being equal, the Mugen would need to be geared at 41/40 (pinion/spur) to match the final drive ratio of the OFNA at 38/40 (pinion/spur). This gives the OFNA a much greater mechanical advantage at the motor that is not lost at the diff.

Just food for thought.

I like your videos. That's super fast on city streets though.
Thanks man. I really dont mind running more aggresive sized gears to go fast. As long as im not overheating or overworking my motors it is fine. I run good high speed fans and heatsinks on all my motors and escs and use my cars daily so I know when they are reliable or overgeared.
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Old 05-25-2016, 03:10 PM   #245
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I have to say if you the right numbers in the speed calculator you can get it pretty close. Pete has a couple fast cars. I also agree that internal diff ratio don't matter..
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Old 05-25-2016, 06:11 PM   #246
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I have to say if you the right numbers in the speed calculator you can get it pretty close. Pete has a couple fast cars. I also agree that internal diff ratio don't matter..
I like the speed calculators. When combined with the info from a data logger, it makes tuning much easier. I wish Castle would fix the new XLX. Their data logger is pretty awesome.

Yeah, the diff ratios don't make a HUGE difference, but there is a mechanical advantage there that results in a little more power at the wheels.

Looks like there is a ROSSA event planned for September just North of LA. Can't wait for that.
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Old 05-26-2016, 01:24 AM   #247
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I like the speed calculators. When combined with the info from a data logger, it makes tuning much easier. I wish Castle would fix the new XLX. Their data logger is pretty awesome.

Yeah, the diff ratios don't make a HUGE difference, but there is a mechanical advantage there that results in a little more power at the wheels.

Looks like there is a ROSSA event planned for September just North of LA. Can't wait for that.
The Poseidon ROSSA event in southern Cali should be awesome this September. I plan to participate along with some other buddies.
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Old 05-26-2016, 09:37 PM   #248
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The Poseidon ROSSA event in southern Cali should be awesome this September. I plan to participate along with some other buddies.
Its too bad that my car is too wide to compete in the 6s class. Should still be a good time.
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Old 05-27-2016, 08:01 PM   #249
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Its too bad that my car is too wide to compete in the 6s class. Should still be a good time.
Too wide? What do you got?
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Old 05-31-2016, 07:07 PM   #250
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Default World's Fastest Kyosho

New personal best with my Kyosho Inferno GT2 on 8s. 143 mph.

https://youtu.be/2XuRQyYhqlE
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Old 06-02-2016, 08:43 AM   #251
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pretty sure they have a 42t ring gear as option. to the fella looking into diff ratios.
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Old 06-02-2016, 08:46 AM   #252
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Has anyone noticed a motor temp change from switching over to a spool on the MGT7?

I'm geared pretty low maybe 90ish right now and the motor likes to spike up fast... I have my spool coming and was hoping that would relieve a little heat.

I've gone through and checked everything and there were no binding issues building the kit.
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Old 06-02-2016, 09:26 AM   #253
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Has anyone noticed a motor temp change from switching over to a spool on the MGT7?

I'm geared pretty low maybe 90ish right now and the motor likes to spike up fast... I have my spool coming and was hoping that would relieve a little heat.

I've gone through and checked everything and there were no binding issues building the kit.
If anything the spool will make it run hotter since you will be running a much smaller spur than the stock 44t. The main reason you are switching to a spool isnto be able to run smaller spurs right?
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Old 06-02-2016, 09:29 AM   #254
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pretty sure they have a 42t ring gear as option. to the fella looking into diff ratios.
Mugen says the 42t diff ring gear must be used with their 12t diff pinion which makes the diff ratio even higher (from 3.38 to 3.5) If the 42t ring gear can be used with the stock 13t ring gear it brings the diff ratio down to 3.23. Stock ring gear is 43t btw.

Last edited by tc4basher; 06-02-2016 at 11:11 AM.
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Old 06-02-2016, 09:47 AM   #255
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Yeah main reason is to use a taller ratio. I figured the center would cause restriction on take off and heat things up.
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