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Post by shaun207 on May 8, 2011 10:54:20 GMT
hey ;D , on fryday just gone , i had some trouble with my photon with it being very twitchy , ( on and off power ) martin young said he thought its generating too much grip .. .. but to save pestering les  for more help , i thought ill ask on here first !! it was nothing like my old shumacher  , meaning the rear end was very planted , i could give it full beans coming out of a corner and it would just stick and i could really chuck it into the corner !! basicly it had loads of steering which was nice !! , but it felt very edgy , but it was better after some changes to the ackerman , i also dropped the front shocks down a hole ... i know many that dont run a photon , so here's my basic settings .. its on pinks front and silvers on the rear . 45wt front and 40wt rear droop 6mm front and 5mm rear ride height 5.2 front and 5.5 rear .. and wishbones all level ( medium low settings to be excact ) roll bars .. 1.4 front and 1.2 rear .. front and rear toe ... front 0.5 toe out and 2.5 rear toe in ... camber 2 on the rear and 1.5 on the front front spool and the diff are in the high position and its all on a super stiff lipo chassis , with mod'd foam top deck ... cheers .. |
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Post by martinchallis on May 8, 2011 11:14:40 GMT
dosent sound a million miles off.... whats your diff like?
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Post by shaun207 on May 8, 2011 11:22:35 GMT
dosent sound a million miles off.... whats your diff like? smooth as silk mate , altho the cars having a strip down , with new bearings , oils etc ... but i will say it was better in practice , but it got knocked about in the first heat ( got hit staight in the back wheel ) and it tweaked the car .. all the tweak was done and the droop was checked etc .. |
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Post by Reuben on May 8, 2011 14:43:33 GMT
stiffen the top of the car up? as in chassis flex (get rid of some).
reduce camber on the front? what are you running?
and how do you mean by twitchy? initial steering, just after initial, mid corner, exit? fast or slow corners, hairpins / chicanes or sweepers?
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Post by lesbaldry on May 9, 2011 6:04:46 GMT
it was nothing like my old shumacher , meaning the rear end was very planted , i could give it full beans coming out of a corner and it would just stick and i could really chuck it into the corner !! basicly it had loads of steering which was nice !! , but it felt very edgy , but it was better after some changes to the ackerman , i also dropped the front shocks down a hole ... i know many that dont run a photon , so here's my basic settings .. its on pinks front and silvers on the rear . 45wt front and 40wt rear droop 6mm front and 5mm rear ride height 5.2 front and 5.5 rear .. and wishbones all level ( medium low settings to be excact ) roll bars .. 1.4 front and 1.2 rear .. front and rear toe ... front 0.5 toe out and 2.5 rear toe in ... cheers .. Shaun apart from roll centers that looks like the basic carpet set up you asked me for last week ;D I do hope it was for the Li po chassis and you changed your pistons back to 3 hole? It seems like the steering has caught you by surprise ,that set up will generate a lot of overall grip,but if you say the car was twitchy,did you try reducing your steering rates a little?...is expo going the right direction?? not silly soft rubber??? Ok things to try to stabilize/ kill steering "a little" Go back to - 3.0 rear toe and 0 or +0.5 front,this will slightly calm the initial steering but the increase in rear - toe will defo soften mid rotation Go med/high all round or even High/low on the front (this may well be your prob Med/low will give too much roll for carpet) Increase front inboard camber link height to 2.5/3.0(alters camber gain) Use Ackerman plate 10 Raise front spool height. |
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Post by shaun207 on May 9, 2011 6:54:28 GMT
it was nothing like my old shumacher , meaning the rear end was very planted , i could give it full beans coming out of a corner and it would just stick and i could really chuck it into the corner !! basicly it had loads of steering which was nice !! , but it felt very edgy , but it was better after some changes to the ackerman , i also dropped the front shocks down a hole ... i know many that dont run a photon , so here's my basic settings .. its on pinks front and silvers on the rear . 45wt front and 40wt rear droop 6mm front and 5mm rear ride height 5.2 front and 5.5 rear .. and wishbones all level ( medium low settings to be excact ) roll bars .. 1.4 front and 1.2 rear .. front and rear toe ... front 0.5 toe out and 2.5 rear toe in ... cheers .. Shaun apart from roll centers that looks like the basic carpet set up you asked me for last week ;D I do hope it was for the Li po chassis and you changed your pistons back to 3 hole? It seems like the steering has caught you by surprise ,that set up will generate a lot of front end grip,but if you say the car was twitchy,did you try reducing you steering rates a little? Ok things to try to stabilize/ kill steering "a little" Go back to - 3.0 rear toe and 0 front,this will slightly calm the initial steering but defo soften mid rotation Go med/high all round or even High/low on the front (this may well be your prob Med/low will give too much roll for carpet) Increase front inboard camber link height to 2.5(alters camber gain) Use Ackerman plate 10  cheers all for your help the car was twitchy , off throttle ( even if i let off down the straight ) and it felt extra nervous .. steering rates was dropped , and its on 3 hole pistons and the rear droop is on .5 on the hoop which equals 5 on the arm .. as this was the indoor car ( the other car is all done for wednesday with your set up ;D ) ... the cars been all stripped , with new bearings ... but ill change the lower arm mounts too ... i dont know what ive done but my reply has gone into les's reply !! ive also edited the first post with camber etc ... cheers again |
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Post by lesbaldry on May 9, 2011 8:13:59 GMT
Shaun your newly edited set up has me confused  Why use the super stiff Lipo chassis and foam top deck?? The med flex Lipo chassis is more than enough coupled with the std top deck,even then Ive narrowed the med chassis to give more flex. the confusing part is your super stiff chassis combo should make the car "less twitchy,less grippy" and will need way different springing and roll centers to work well If you want to run on carpet short tracks stick to the kit li po chassis and top deck and speak to Ginge he has a good stable working set up for that chassis/top deck combo I could never get that chassis to work and it was even worse with the foam top deck,but should you want to perceiver with it try this. Put top deck back to std. High/low front roll centers Med /high rear Silver/Blue springs with 1.2 front roll bar Or Blue/Blue with 1.4 front roll bar 2.5mm on front and rear inboard camber links 1mm on front outboard camber link 2.5 on rear outboard camber link. This is close to my"best" technical short track carpet set up with the med chassis but the softer springing should compensate for your stiffer chassis. the "rule of thumb" mate is the stiffer the chassis the softer the springing and raise the roll centers slightly(camber links as well as wishbones) to stop the softer springs letting the car roll too much. Ps "raising the roll centers" (wishbone mounting points) is actually lowering the true roll center/cg |
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Post by ginge on May 9, 2011 8:36:09 GMT
i may let you look at the set up shaun....but you will have to sign and letter saying that you will never tell anyone!!!! its TOP secret  ;D ;D Ginge |
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Post by lesbaldry on May 9, 2011 11:06:33 GMT
Shaun the stiffer you run your chassis/top deck the more accurate and precise your set up must be,it also narrows the cars set up window quite a bit,todays flexi chassis do allow for slight in-accuracy's/tweaks but thats no excuse for poor basics.....ask Ginge he's found out how important the odd 0.5mm here and there can make An accurate "kit set up" can often run better than the latest so called fastest if not done correctly....the hard part is understanding what to do,how to do it and why! don't be scared to ask no mater how daft you might think the question is,not all of us have an engineering back ground.....we all started somewhere chap!! sometimes its nice to get back to basics cause the so called experts can still miss the wood for the trees  ....as all of us are still learning |
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Post by shaun207 on May 9, 2011 18:03:38 GMT
Shaun your newly edited set up has me confused Why use the super stiff Lipo chassis and foam top deck?? The med flex Lipo chassis is more than enough coupled with the std top deck,even then Ive narrowed the med chassis to give more flex. the confusing part is your super stiff chassis combo should make the car "less twitchy,less grippy" and will need way different springing and roll centers to work well If you want to run on carpet short tracks stick to the kit li po chassis and top deck and speak to Ginge he has a good stable working set up for that chassis/top deck combo I could never get that chassis to work and it was even worse with the foam top deck,but should you want to perceiver with it try this. Put top deck back to std. High/low front roll centers Med /high rear Silver/Blue springs with 1.2 front roll bar Or Blue/Blue with 1.4 front roll bar 2.5mm on front and rear inboard camber links 1mm on front outboard camber link 2.5 on rear outboard camber link. This is close to my"best" technical short track carpet set up with the med chassis but the softer springing should compensate for your stiffer chassis. the "rule of thumb" mate is the stiffer the chassis the softer the springing and raise the roll centers slightly(camber links as well as wishbones) to stop the softer springs letting the car roll too much. Ps "raising the roll centers" (wishbone mounting points) is actually lowering the true roll center/cg cheers les , i will have a go at the car later and do the advised changes ... but i didnt think ginge had a lipo spec chassis , his was a 6cell one .. ill bring it on wednesday for you to have a quint at it !! ..cheers shaun |
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Post by lesbaldry on May 9, 2011 22:28:15 GMT
but i didnt think ginge had a stiff lipo spec chassis , his was a 6cell one .. He didn't Shaun but all due respects to Ginge at that time he was a relative newby running 17.5 rather sedately(not any more  so the set up should of been stable and easy to drive as he wasn't putting the same amount of flex into the chassis as you would. Don't panic mate I wont give you a "bum steer"...I didn't at west London....we'll sort your stiffy prob out on weds ......whoooops  |
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Post by shaun207 on May 9, 2011 22:41:42 GMT
cheers les , ill bring the car along on wednesday....see ya then ;-)
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Post by shaun207 on May 13, 2011 22:59:51 GMT
well ive done another meeting on the rug !! .. changed a few bits , like roll centres , ackerman settings , and it felt better , still loads of grip but nothing like it was like before !! was good in practice , was good in the first heat ( apart from getting taken out by a back marker !! ) and ended up 3rd !! , but i still wanted to take a bit of grip out of it and ended up changing the spring rates , so i changed it from pinks / silvers to gold front and pinks on the rear ( on hpi springs ) and it was better again !! then changed from 28jb's to 32 jb's for the 3rd heat , and it was better after spending 1/2th the race scrubbing them in .. qualified 4th for the a-final , and after the usall crashes on the first lap ( and in someone elses crash ) got up to 2nd .. then after a crash and a hit from behind , my rear belt popped off !!  but it was alot better , and easyer to drive , just need a bit more steering now  .... but cheers for your help |
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for more help , i thought ill ask on here first !! 
, meaning the rear end was very planted , i could give it full beans coming out of a corner and it would just stick 
;D ;D
....as all of us are still learning 
so the set up should of been stable and easy to drive as he wasn't putting the same amount of flex into the chassis as you would.
.... but cheers for your help