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Old 10-05-2012, 08:09 PM   #4351
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quick question .......

I was wondering if anyone is running front gear diffs? And what fluid wts you use or reccommend and 2 gear or 4?

I run on a med bit carpet on rubber tires and one of the locals said it looks like my spool is causing the front to overdrive. I enter the corners good but hit the throttle and the front wants to pull the rear around.

I basically have mirror'd Martin's setup from Snowbirds if anyone is wondering my setup.

I have 2 gear diff in the rear with 3000 right now.


Other then this quirk I like the car overall, very happy with it.
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Old 10-05-2012, 08:20 PM   #4352
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quick question .......

I was wondering if anyone is running front gear diffs? And what fluid wts you use or reccommend and 2 gear or 4?

I run on a med bit carpet on rubber tires and one of the locals said it looks like my spool is causing the front to overdrive. I enter the corners good but hit the throttle and the front wants to pull the rear around.

I basically have mirror'd Martin's setup from Snowbirds if anyone is wondering my setup.

I have 2 gear diff in the rear with 3000 right now.


Other then this quirk I like the car overall, very happy with it.
use 700,000 or cleaning putty
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Old 10-06-2012, 08:04 AM   #4353
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use 700,000 or cleaning putty
Thanks.

700,000 with 2 or 4 gears?
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Old 10-06-2012, 08:13 AM   #4354
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Thanks.

700,000 with 2 or 4 gears?
I run 2 but honestly I can't tell the difference between them lol
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Old 10-06-2012, 09:24 AM   #4355
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Thanks.

700,000 with 2 or 4 gears?
at 700.000cst it really will not matter too much thats as heavy as anti sieze grease.

also try playing around with your droops alittle. sounds like you have a weight transfer issue... with the heavier diff on the front you will transfer even more weight quicker.

while the diff will give you more on throttle steering exiting the corner the added weight trasfer will most likely remedy the effect you are trying to get.

what you want to do is keep the front on the ground more and reduce your chatter on your shafts if using standard axles. using dcj you will get more steering and less chatter which will reduce the push you are getting on corner exit.
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Old 10-06-2012, 11:18 AM   #4356
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Originally Posted by Robbob View Post
quick question .......

I was wondering if anyone is running front gear diffs? And what fluid wts you use or reccommend and 2 gear or 4?

I run on a med bit carpet on rubber tires and one of the locals said it looks like my spool is causing the front to overdrive. I enter the corners good but hit the throttle and the front wants to pull the rear around.

I basically have mirror'd Martin's setup from Snowbirds if anyone is wondering my setup.

I have 2 gear diff in the rear with 3000 right now.


Other then this quirk I like the car overall, very happy with it.
I think 3000 in the rear is too thick for medium-bite carpet from my experience. I've never used over 2000 unless traction was really high....
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Old 10-06-2012, 01:58 PM   #4357
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at 700.000cst it really will not matter too much thats as heavy as anti sieze grease.

also try playing around with your droops alittle. sounds like you have a weight transfer issue... with the heavier diff on the front you will transfer even more weight quicker.

while the diff will give you more on throttle steering exiting the corner the added weight trasfer will most likely remedy the effect you are trying to get.

what you want to do is keep the front on the ground more and reduce your chatter on your shafts if using standard axles. using dcj you will get more steering and less chatter which will reduce the push you are getting on corner exit.
I may have worded it wrong but I dont have a push, its more like a hook. I can lift the throttle, enter the corner but the moment I try to apply throttle again mid to exit the rear wants to come around. Drift style mid to corner exits.

I can make the car push on exit, Ive softened the rear up alot to plant it more. The moment I try to tighten the car up in the corner the back gets washy.

But I like your mention about the front chatter, I do have that some. Thanks for the reply.


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I think 3000 in the rear is too thick for medium-bite carpet from my experience. I've never used over 2000 unless traction was really high....
Will keep that in mind when I can get the rear to settle down a bit more. Thanks.
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Old 10-06-2012, 05:48 PM   #4358
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I don't know specifically but I was told a stupid fast motor I saw was hand-wound.....! And it was a D3 I think, not 3.5, sorry!

For ReVtech gearing..... depends on the track! What size?
It's a huge outdoor track, maybe 200 foot back straight away

Matt
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Old 10-07-2012, 12:13 AM   #4359
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It's a huge outdoor track, maybe 200 foot back straight away

Matt
At the paved nationals (200ft) I believe 17.5 was geared 3.0-3.2, depending on motor.....
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Old 10-07-2012, 12:39 AM   #4360
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I may have worded it wrong but I dont have a push, its more like a hook. I can lift the throttle, enter the corner but the moment I try to apply throttle again mid to exit the rear wants to come around. Drift style mid to corner exits.

I can make the car push on exit, Ive softened the rear up alot to plant it more. The moment I try to tighten the car up in the corner the back gets washy.

But I like your mention about the front chatter, I do have that some. Thanks for the reply.




Will keep that in mind when I can get the rear to settle down a bit more. Thanks.
do the opposite of what I said I thought you were having a nasty push problem...

The biggest help for crazy spin is body. I used to use the audi then I swithched to speed6 the difference was major. it used to be nervous now its almost at a push level.

give 15 to 20 negative expo on steering and reduce the servo speed a notch or two and see how that effects.

these are of course things to look at besides the obvious setups changes

if you are having spin problems try Mustafa's older setups very little steering all turning done with the throttle
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Old 10-07-2012, 02:17 AM   #4361
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Had another practise night last night on the up-coming nationals track... tried some quite big changes to the car, and one which was a really suprising one.

Tested out the following, and all felt there was an improvement;
First run, started out with the same settings as at the recent QLD titles, with the exception of 4hole pistons/500wt oil - Good roll control, and nice enough over the bumps. Possibly on lower traction 450 would be better
Second run, moved to lower roll centre + Stiffer (Ride Blue) springs - 0.5mm under all the blocks. Flat out, IMO, the car's lower pin height is too high in kit settings. Every other car on the market use's a pin height between 5-5.5mm above the chassis plate, kit on the serpent is 6mm, which helps to explain why needing to run the car quite a bit softer to generate traction.
With the lower blocks, car was much more settled, and generated the side bite I was after, even with the harder springs (I had been running the Greens).
Third run I tried a narrower rear on the hexes. Simply did this by putting the 747 optional -1mm hubs (#804195) on the rear of the car, with a 0.5mm shim in place. Again, breaking out the digi calipers in the pits, the rear of the car is a bit wider than most, even with the similar width blocks and arms.
Making the car narrower again helped with rear grip, and also helped to get the car to react in the middle faster, albeit with an on-power push.

Next up was to narrower the rear down even more, by reducing the rear-toe to 2.5, attempting to get the car to rotate better on-power. Doing this change actually gave the car a big mid-corner push, so the opposite of what I expected, although this maybe was due to combination of narrowing the rear, as well as lengthening the wheelbase. Car was quicker down the straight, but that wasn't really needed with mod! :P

Last change for the night, was to bolt on the modded top deck I made up a while back. Again, looking at other cars around, almost all have have a brace above the steering posts, which is effectively where the front flex point is. So I wanted to test this out, and see if there would be any change (as a recap, I took a standard 2mm top deck, and just cut away the material in the shape of the flexi, bar the crossing brace).
Anyway, this was a really suprising change. I expected it to make the car push more, so had dropped the inner rear link down to 3mm...and my expectation was completely wrong, the car gained a lot of steering! Went from struggling through the sweepers, to being able to hug tight, and having too much in the middle and exit. A real massive jump in handling, much larger than I expected. I have a thought that the front of the car is too flexy with the flexi deck, certainly for a mod/high-grip combination... with the car flexing to a point of 'pinging' the grip away through overflexing (much like I mentioned previously with the rear mount set-up).
last run, I but the links back to where it was on the rear, and went to HPI Silvers. Posted my fastest runs' of the night, but car was still a bit tricky to drive, need to make some other changes (I think mainly to the camber links, and back to the 3 rear toe) to get a better balance, but that top deck is now staying on the car... I also suspect it might work quite well with the other motor mount... :P

Ed
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Old 10-07-2012, 04:01 AM   #4362
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Last change for the night, was to bolt on the modded top deck I made up a while back , that top deck is now staying on the car... I also suspect it might work quite well with the other motor mount... :P.
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Ed, Always great reading your reports. Looking forward to catching up at the Nats.

Ill bring the top deck, You bring the dremel
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Old 10-07-2012, 05:10 AM   #4363
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No prob, really trying to get the car sorted out in time for the nats, will have probably another couple of test days and thats it... long list of stuff still to try!!

For those who are confused by the top deck, I took a 2mm carbon (non flexy - http://www.serpent.com/product/401374/) and cut away the material at the front to match the flexi (actually used a flexie as a template) with the exception of the brace, as can be seen in the attached pic.

HiH
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Serpent S411-img_2972.jpg  
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Old 10-07-2012, 05:24 AM   #4364
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Originally Posted by Robbob View Post
quick question .......

I was wondering if anyone is running front gear diffs? And what fluid wts you use or reccommend and 2 gear or 4?

I run on a med bit carpet on rubber tires and one of the locals said it looks like my spool is causing the front to overdrive. I enter the corners good but hit the throttle and the front wants to pull the rear around.

I basically have mirror'd Martin's setup from Snowbirds if anyone is wondering my setup.

I have 2 gear diff in the rear with 3000 right now.


Other then this quirk I like the car overall, very happy with it.
I have the same problem, changing the droop helped some. But still looking for more onpower grip and steering.
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Old 10-07-2012, 09:33 AM   #4365
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Hey,

I wanna thanks Benzaah, TryHard, RasCalDK and cwoods34 for the help some pages before. I made some of the changes you suggested and my car now is going near to what I need.

today I have a race, and the car was easier and faster than ever. Yesterday I spend the afernoon testing some of the changes, first of all, I shortened the upper rear link (inner rear hub) and everything came round, in the exit of the corner I most of the steering that I was looking for.
Later on, I make the rear blocks flat, ad I win something more, later on I introduce the spool and No I was Happy with the spool!!! For the very first time.

This race was my last TC race of the season, so for the winter I will prepare one Mazda 6 and will check the nylon spool.

Kind regards
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