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Old 02-16-2010, 04:48 PM   #76
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Hey Erik....frustrating ..isn't it !! Bottom line is...remember that just because there are guidelines or generally accepted rules of thumb does not mean that your car has to be conventional. Tires, wheel offsets, stiffness of chassis etc,etc are ALL important but so are YOU ! You have to drive it and like it.. so what may be right for me can be totally wrong for you.
Use the existing info as a baseline...then adapt it to your needs. And you can't be afraid to try things that don't seem to make sense. I did and my car handled better than I've ever seen and totally contradicted 99% of the setups I've seen for this car.
I wish i had John Stranahan's know how...at least then some of these changes would make some kind of sense.
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Old 02-16-2010, 05:19 PM   #77
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Hey Erik....frustrating ..isn't it !! Bottom line is...remember that just because there are guidelines or generally accepted rules of thumb does not mean that your car has to be conventional. Tires, wheel offsets, stiffness of chassis etc,etc are ALL important but so are YOU ! You have to drive it and like it.. so what may be right for me can be totally wrong for you.
Use the existing info as a baseline...then adapt it to your needs. And you can't be afraid to try things that don't seem to make sense. I did and my car handled better than I've ever seen and totally contradicted 99% of the setups I've seen for this car.
I wish i had John Stranahan's know how...at least then some of these changes would make some kind of sense.
+1

My springs maybe too soft. Dianosing the problem while driving is not my strong suite, but I'm getting better. My setup works for me but I still looking for ways to make it better, that's why I'm here I've seen guys at our track have the same chassis and electronics try each other's setup and say it's completely undrivable. My setup oversteers a little but I like it better than understeering. The shock thing bothered me at first too. Also the long camberlinks with low roll blocks seems counterdicting each other. I just want to get it so I'm not fighting the car and can focus on the driving.
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Old 02-16-2010, 07:01 PM   #78
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As if all this info does'nt make your brain hurt already, anybody ever try the over / underdrive pulleys?

Was also thinking, with the new 25.5 motors and the loss of specific FDR, useing the 41 tooth belt pulleys front and rear would change your internal ratio from 1.83 to 1.78. For those of us without a spur adapter, we might be able to go this route for further adjustment / fine tuning instead. I use the 108T / 64P spur with a 44T pinion. With the current Internal ratio of 1.83, this give me the 4.49FDR. By changing the internal ratio to 1.78, my FDR becomes 4.36 I dont know if belt tension would become an issue. Just a thought.

Last edited by GI JOE; 02-19-2010 at 05:53 PM.
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Old 02-17-2010, 08:15 AM   #79
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As if all this info does'nt make your brain hurt already, anybody ever try the over / underdrive pulleys?

Was also thinking, with the new 25.5 motors and the loss of specific FDR, useing the 41 tooth belt pulleys front and rear would change your internal ratio from 1.83 to 1.78. For those of us without a spur adapter, we might be able to go this route instead. I use the 108T / 64P spur with a 44T pinion. With the current Internal ratio of 1.83, this give me the 4.49FDR. By changing the internal ratio to 1.78, my FDR becomes 4.36 I dont know if belt tension would become an issue. Just a thought.
Never tried over/under drive.
Checked out the VTA site FDR calculator, thier sample showed a FDR of 4.0.
Ran the numbers for a XXX and came up with 49t 64p gives a 4.03 FDR. BUT I don't know if the calculator has been updated. NOVAK doesn't give a recommended FDR either, so I expect some testing will happen over the next few months. Our race director has ordered his 25.5 already, and I know he'll be testing it. Once I hear want he found I'll pass it along.

Been thinking about the spring deal some more. I'll stiffen all of them one weight and test tonight. I suspect I'll start sliding-loss of side bite.I think a neutral slide could be caused by over-driving too which I am guilty of as well.
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Old 02-19-2010, 11:45 AM   #80
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Quick note (and a bump to keep this thread up there )

I went to a track to test speedo changes and I found the setup I have been chasing for outdoor asphalt, completely rocks for the indoor asphalt (WCRC). Handling wise, the car has never felt better. Turns in great, push is non-existent, even some throttle induced oversteer, and I had more grooved (consistent) laps than ever.

I now wonder how much influence the speedo changes had on the overall setup? I can actually feel the drag brakes I added. Now when I get to the corners I am getting better weight transfer instantly just by letting off the throttle. All in all, the car is now a complete 'land missile'. I left the track with it running twice as fast and snappy as before.

Could the added speed and improved braking 'made' my setup work better?

Maybe my driving style is better suited for faster speeds?!!
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Old 02-19-2010, 04:00 PM   #81
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Way to go Erik !! As always, you tune for the surface and layout of the track. Apparently, what was not so good on the outdoor track worked really well on the indoor. Track temp and layout probably were biggest factors here. Make sure you record the setup including your esc settings. When you go back outdoors you can reference it. I would also try to compare the current setup to someone at the outdoor track who seems to have a dialed car. Then try subtle changes.
C&B..haven't ried to play much with the pulleys. According to most available setups very few people used it..but...I also noticed most of the track types were larger,more open designs or carpet of the same. I would think on tighter ,technical tracks the under/over drive could be usable. Now that I'm using the spool I'm going to experiment further with the pulley.
BTW, note to all....still needing sway bar sets. I found a front but would like another and I need rear sets. If anybody knows of a source...please let me know.
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Old 02-19-2010, 05:07 PM   #82
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I'll check the discount Bin at the track next Weds for sway bars...never know. I tried stiffer springs last Weds.2 lbs all around, crisper driving, but I must have had a target on my back. I held the line but got bumped in every heat and went over the boards once...broke my spoiler and a front hub. It was one of those days. I'll leave them heavier ones on another week and see what happens
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Old 02-22-2010, 12:33 AM   #83
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Just checking in...

Raced today...had more pace today than ever. I got a few laps down solid into 'Intermediate' territory, but I am still too inconsistent in my driving to stitch 5 min of good laps together. I lost to the top Rookie by 10 sec or so in the main. I guess practice, practice.

Question for you guys: My buddy has a XXX-S as well and he is running the Novak GTB in 17.5 with me. We are trying to get his car geared tall enough to keep up, but we are limited with the spur options for this car. I believe there is a 86, 88, and 90T spur. Even with the 88, he still needs a pinion over 43T just to get to the 4.0 FDR level. THe biggest I can get into my car is 38, and I have to pull the spur just to get it in there. I just can't see how the 86 will help that much.

Has anyone else faced this issue and how have you solved?
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Old 02-22-2010, 01:13 PM   #84
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Erik..now thats a simple one.....GO 64 PITCH !!! I use the 108t 64p spur which seems to be the better choice over the larger 128t. To get to the appropriate fdr you're just about going to the limit for the xxxs but I've gone all the way to 50t with no problem.
BTW, is 4.0 the magic number for your track?? Just wondering why that ratio?
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Old 02-22-2010, 01:24 PM   #85
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Erik..now thats a simple one.....GO 64 PITCH !!! I use the 108t 64p spur which seems to be the better choice over the larger 128t. To get to the appropriate fdr you're just about going to the limit for the xxxs but I've gone all the way to 50t with no problem.
This is the reason I asked about running 41 tooth belt pulleys front and rear. 108T spur, 50T pinion and an internal ratio of 1.78 would net a FDR of 3.84

This may be a way to eek out a taller FDR without useing a spur adapter...problem is, I dont have the 41 tooth pulleys yet to try this and see if belt tension would be an issue.
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Old 02-22-2010, 02:25 PM   #86
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This is the reason I asked about running 41 tooth belt pulleys front and rear. 108T spur, 50T pinion and an internal ratio of 1.78 would net a FDR of 3.84

This may be a way to eek out a taller FDR without useing a spur adapter...problem is, I dont have the 41 tooth pulleys yet to try this and see if belt tension would be an issue.
51t pulley dont make much diffrence, a 108T spur or a Tekin with a 203 software solve can all your FDR problems.

da john wee
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Old 02-22-2010, 02:48 PM   #87
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Originally Posted by Evoracer View Post
Erik..now thats a simple one.....GO 64 PITCH !!! I use the 108t 64p spur which seems to be the better choice over the larger 128t. To get to the appropriate fdr you're just about going to the limit for the xxxs but I've gone all the way to 50t with no problem.
BTW, is 4.0 the magic number for your track?? Just wondering why that ratio?
Yeah, 3.6 to 4.0 seems to be the ticket for the GTB at my track (or so I am told by the local GTB'ers).

I was hesitent to go 64 pitch as I have SO MANY 48p pinions. To have to buy new pinions at $5 a pop is not appealing. Even less appealing to my buddy, who just happens to be unemployed right now. As I am typing this, Mr. John Wee just chimed in with the $200 solution Yeah, true. My buddy is regretting not buying the Tekin when he was employed, as I am regretting not buying the Pro verison.

Maybe we could just run mod and his GTB would not be as bad off. I could probably get away with running a 10.5 on my RS - Not sure though...
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Old 02-22-2010, 03:06 PM   #88
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No offense to John but...."I aint payin for no artsy fartsy Tekin just to make fdr !!!"

This really is a non issue so don't drive yourselves nuts. I use a Havoc and a Havoc Pro and run both VTA and RCGT. The Losi 108t spur for the xxx-s is still easily available so there's no reason to consider using a spur adaptor.
As for the 48p vs.64p. The biggest problem is availability of larger 48p pinions. Most companies just don't make them. 64p is much more available primarily because thats what more racers use and certain classes (oval pan car in particular) have always used them because of the ratios they require.
Erik, start simple....108 spur with the small variety of pinions you'll need for your track. You'll find that there's probably 3 gears you really need to provide a usable fdr range.
And BTW, the xxxs isn't the only car you'd have problems making those kind of fdr's with. 48p just isn't easy to use now that 3.5 to 4.5 fdr's are the norm in many cases.

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Old 02-22-2010, 07:40 PM   #89
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Just wanted to let all of you know that I have one up for sale in the for sale item. Check it out please. I really need to sell this. Not trying to make anyone mad just wanted to let you guys know who race these know about it.
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Old 02-25-2010, 08:15 PM   #90
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Default 25.5 test results for VTA

well here's what our race director said about his first run with a 25.5.

Quote:
Originally Posted by HobbyPLEX
Got my 25.5 stator on Friday, hope to have it in the car to try it Wednesday.

Tim Ski

Quote:
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Cool, we all eagerly await a track report, FDR & a chance to be beaten by a 25.5

Results from the 25.5 motor test last night.

Round #1 - 5.0 FDR, 19 laps, 15.1 fast lap, Q 6th
Round #2 - 4.2 FDR, 20 laps, 14.7 fast lap, Q 6th
"A" Main -- 4.2 FDR, 32 laps, 14.5 fast lap, F 4th

Last week with 21.5

Qualifying (5 Mins) - 5.0 FDR, 21 laps, 14.1 fast lap, TQ
"A" Main (8 Mins) -- 5.0 FDR, 33 laps, 14.0 fast lap, F 3rd

25.5 didn't feel like it had the snap out of the corner like the 21.5 but, I think I was keeping more speed through the corner as I wasn't getting off the throttle as much. The 4.2 FDR 25.5 had equal lap times and straight away speed as the 5.0 FDR 21.5s had.

I'll put it in my other car and do some more testing and have a few others give it a test drive to get some more feedback.

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