1LikesStreet Jam SJF01 Formula 1. Niiiiiiiiice!
01-30-2015, 08:40 PM
#273
Last night, evochick & I raced our Street Jams our local club, and there is some good news, but also some not so good, which will explain later.
During the practice session before the racing started, I was able to do a direct comparison between the Mk 1 shocks & Mk 2 shocks. With the Mk 1 shocks on the car, I drove the car around the track for around 8-10 laps, and the car felt a little better with the lighter oil, but still felt like the rear end was always on the verge of letting go, and inclined to spin out.
After those 8-10 laps I took the car back to my table, and swapped out my Mk 1 shocks & put Beth's Mk 2 shocks in the car.
After a tentative 2 or 3 laps tho get a feel of the different shocks, I noticed a marked improvement of the cars handling, being able to accelerate a little more out of turns without the rear end wanting to break loose, but it still didn't look as planted as Beth's car.
After finishing that practice, I swapped out the shocks, to put my Mk 1 shocks back into the car, then Beth & I compared how they felt on the bench next to each other, and Beth's still felt a bit softer & "lighter" when pressing the cars down at the rear end by finger. Beth then looked at my shocks and adjusted the Medium/Soft springs by turning the spring ring on my shocks to the softest setting.
The difference to a few turns on the spring adjuster made the biggest positive difference to my car than anything else I had tried doing, because the car felt like nothing like how it was before this change. I was able to get back on the power out of a corner more earlier than I had been able to before, and the car also felt more planted & stable through the corners, almost to the point of feeling like a touring car.
For all the racing that night, Beth, I , and one other club member who was driving a very dialed in Tamiya F104v2 were charging through the field in both our qualifying heats, and our final heat on the night, which lead to me tq'ing, and finishing in first in the final.
I have to say, this result was something that I never ever thought I would be doing on the night, I was all but certain that I would be struggling in frustration with the car all night, and wanting to just not race it at all on the night.
Even with this result, I still went ahead and ordered the Mk 2 shocks, along with the machined pistons & spacers to see if they will also improve on the cars handling.
Now, for the not so good.
Even after changing the caster from 7 degree's to 5 degree's, the car still wanted to push in the corners from mid turn, to corner exit. I know this can be explained because of the improvement to the rear end grip, but my car was also doing this even when the rear end was feeling "loose".
The one thing that was most noticeable with the caster change, was that the car felt more "nervous" with direction changes, and when turning into the corners. Beth and I on the night, were trying to "throw" our cars into the tight corners, to unsettle the car slightly so the rear end would come around, which allowed the both of us to get our cars quicker around the tight corners.
On the faster turns the cars were driving very well, with only a small hint of under steer.
Hopefully we can both work on getting the cars to under steer less out of the tighter corner, without sacrificing some if any, rear end grip.
Beth, I know I have said this often before, but I want to thank you for all your advice, help & patience with this car & me. I also want thank you for persisting to help build up my confidence, both in the car & myself.
*edit* Since this change my satisfaction with the car on the track has improved, but my opinion about building & quality control remains the same, one club member who has also bought a Street Jam offered me money to have the car built, but I declined explaining why I didn't want to build it for him.
Rob.
During the practice session before the racing started, I was able to do a direct comparison between the Mk 1 shocks & Mk 2 shocks. With the Mk 1 shocks on the car, I drove the car around the track for around 8-10 laps, and the car felt a little better with the lighter oil, but still felt like the rear end was always on the verge of letting go, and inclined to spin out.
After those 8-10 laps I took the car back to my table, and swapped out my Mk 1 shocks & put Beth's Mk 2 shocks in the car.
After a tentative 2 or 3 laps tho get a feel of the different shocks, I noticed a marked improvement of the cars handling, being able to accelerate a little more out of turns without the rear end wanting to break loose, but it still didn't look as planted as Beth's car.
After finishing that practice, I swapped out the shocks, to put my Mk 1 shocks back into the car, then Beth & I compared how they felt on the bench next to each other, and Beth's still felt a bit softer & "lighter" when pressing the cars down at the rear end by finger. Beth then looked at my shocks and adjusted the Medium/Soft springs by turning the spring ring on my shocks to the softest setting.
The difference to a few turns on the spring adjuster made the biggest positive difference to my car than anything else I had tried doing, because the car felt like nothing like how it was before this change. I was able to get back on the power out of a corner more earlier than I had been able to before, and the car also felt more planted & stable through the corners, almost to the point of feeling like a touring car.
For all the racing that night, Beth, I , and one other club member who was driving a very dialed in Tamiya F104v2 were charging through the field in both our qualifying heats, and our final heat on the night, which lead to me tq'ing, and finishing in first in the final.
I have to say, this result was something that I never ever thought I would be doing on the night, I was all but certain that I would be struggling in frustration with the car all night, and wanting to just not race it at all on the night.
Even with this result, I still went ahead and ordered the Mk 2 shocks, along with the machined pistons & spacers to see if they will also improve on the cars handling.
Now, for the not so good.
Even after changing the caster from 7 degree's to 5 degree's, the car still wanted to push in the corners from mid turn, to corner exit. I know this can be explained because of the improvement to the rear end grip, but my car was also doing this even when the rear end was feeling "loose".
The one thing that was most noticeable with the caster change, was that the car felt more "nervous" with direction changes, and when turning into the corners. Beth and I on the night, were trying to "throw" our cars into the tight corners, to unsettle the car slightly so the rear end would come around, which allowed the both of us to get our cars quicker around the tight corners.
On the faster turns the cars were driving very well, with only a small hint of under steer.
Hopefully we can both work on getting the cars to under steer less out of the tighter corner, without sacrificing some if any, rear end grip.
Beth, I know I have said this often before, but I want to thank you for all your advice, help & patience with this car & me. I also want thank you for persisting to help build up my confidence, both in the car & myself.
*edit* Since this change my satisfaction with the car on the track has improved, but my opinion about building & quality control remains the same, one club member who has also bought a Street Jam offered me money to have the car built, but I declined explaining why I didn't want to build it for him.
Rob.
Last edited by ta04evah; 01-30-2015 at 10:43 PM. Reason: Addional information
01-30-2015, 11:06 PM
#274
you know I am a big fan of the saying "if your mate is off the pace its just not a race" We will get the slow speed push sorted eventually.
For next week I will go back to 7deg caster but ill leave the servo where it is in the very forward position, I think this will give us a little more lock for the slow corners. And I know I hate using them but I still have soft fronts to try as a last resort.
Beth.
01-30-2015, 11:28 PM
#275
I know Rob you know I am a big fan of the saying "if your mate is off the pace its just not a race"
We will get the slow speed push sorted eventually.
For next week I will go back to 7deg caster but ill leave the servo where it is in the very forward position, I think this will give us a little more lock for the slow corners. And I know I hate using them but I still have soft fronts to try as a last resort.
Beth.
you know I am a big fan of the saying "if your mate is off the pace its just not a race" We will get the slow speed push sorted eventually.
For next week I will go back to 7deg caster but ill leave the servo where it is in the very forward position, I think this will give us a little more lock for the slow corners. And I know I hate using them but I still have soft fronts to try as a last resort.
Beth.
01-31-2015, 01:57 AM
#276
I know Rob you know I am a big fan of the saying "if your mate is off the pace its just not a race"
We will get the slow speed push sorted eventually.
For next week I will go back to 7deg caster but ill leave the servo where it is in the very forward position, I think this will give us a little more lock for the slow corners. And I know I hate using them but I still have soft fronts to try as a last resort.
Beth.
you know I am a big fan of the saying "if your mate is off the pace its just not a race" We will get the slow speed push sorted eventually.
For next week I will go back to 7deg caster but ill leave the servo where it is in the very forward position, I think this will give us a little more lock for the slow corners. And I know I hate using them but I still have soft fronts to try as a last resort.
Beth.
Mk 2 shocks are on their way as I got the email today with the tracking number.
@malcnz, I normally do have toe out on the front of the car, which did help a little, along with helping to track straight, so I may add a little more to see how that goes too.
Some F1 final action from our local club last night, Beth's is the yellow car with white wings starting from 3rd, the dark blue car starting from 2nd is the dialed in F104, and the blue/green/white car starting from pole is my car.
https://www.youtube.com/watch?v=W6iq...&feature=share
Rob.
01-31-2015, 08:37 PM
#278
Rob,
How cold is it there? From the video it looks like most of the field was lacking sufficient front tire grip, how do the soft fronts work?
It also looks as though you did not have enough ackerman in your car the slip angle through the infield is off contributing to the front washing out mid corner.
you will want to place your servo in the car with the links sufficiently swept back at neutral so that the inside link is straight across the chassis at full lock. Adjust the bumpsteer to your preference, raising the link at the horn will mellow steering response and help with exit steering. lowering the horn mount will make the car turn in better with a more aggressive feel.
The 2 biggest improvements I made to resolve my mid corner / on power push was to mount the rear pod links on the underside shimmed down 2mm and use very soft front spings like a tamiya silver or ride blue. Mounting the pod links on the underside of the mount will make the rear steer into as it rolls. The unique pod design on the stj provides less weight transfer and thus requires softer front springs to generate enough roll in low speed sections.
I am still lacking the forward bite on carpet of a levered t-bar car but it is now on par with any spring car I have seen. The forward bite issue seems limited to higher grip conditions where a sprung t-bar can load up and lunge the car forward improving acceleration. Next time out I will try pitching the entire pod to see if I launch it better but without some sort of spring device to load i think its unlikely i'll be able to match t-bar acceleration.
Your buddy with the 104 should try increasing his static caster and shimming the front of his upper arm to induce a negative reactive caster effect. On my 104 link car i run 6-8deg static w/ 3-5mm shim on the camber plate. On the t-bar car I run 8-12deg caster with 5-6mm camber plate shim. The extra caster helps with the inherent on power push and the negative reactive helps keep steering from washing out mid corner.
Where is your f1 relative to the 17.5 & 21.5 sedans?
How cold is it there? From the video it looks like most of the field was lacking sufficient front tire grip, how do the soft fronts work?
It also looks as though you did not have enough ackerman in your car the slip angle through the infield is off contributing to the front washing out mid corner.
you will want to place your servo in the car with the links sufficiently swept back at neutral so that the inside link is straight across the chassis at full lock. Adjust the bumpsteer to your preference, raising the link at the horn will mellow steering response and help with exit steering. lowering the horn mount will make the car turn in better with a more aggressive feel.
The 2 biggest improvements I made to resolve my mid corner / on power push was to mount the rear pod links on the underside shimmed down 2mm and use very soft front spings like a tamiya silver or ride blue. Mounting the pod links on the underside of the mount will make the rear steer into as it rolls. The unique pod design on the stj provides less weight transfer and thus requires softer front springs to generate enough roll in low speed sections.
I am still lacking the forward bite on carpet of a levered t-bar car but it is now on par with any spring car I have seen. The forward bite issue seems limited to higher grip conditions where a sprung t-bar can load up and lunge the car forward improving acceleration. Next time out I will try pitching the entire pod to see if I launch it better but without some sort of spring device to load i think its unlikely i'll be able to match t-bar acceleration.
Your buddy with the 104 should try increasing his static caster and shimming the front of his upper arm to induce a negative reactive caster effect. On my 104 link car i run 6-8deg static w/ 3-5mm shim on the camber plate. On the t-bar car I run 8-12deg caster with 5-6mm camber plate shim. The extra caster helps with the inherent on power push and the negative reactive helps keep steering from washing out mid corner.
Where is your f1 relative to the 17.5 & 21.5 sedans?
02-01-2015, 05:19 PM
#279
Rob,
How cold is it there? From the video it looks like most of the field was lacking sufficient front tire grip, how do the soft fronts work?
It also looks as though you did not have enough ackerman in your car the slip angle through the infield is off contributing to the front washing out mid corner.
you will want to place your servo in the car with the links sufficiently swept back at neutral so that the inside link is straight across the chassis at full lock. Adjust the bumpsteer to your preference, raising the link at the horn will mellow steering response and help with exit steering. lowering the horn mount will make the car turn in better with a more aggressive feel.
The 2 biggest improvements I made to resolve my mid corner / on power push was to mount the rear pod links on the underside shimmed down 2mm and use very soft front spings like a tamiya silver or ride blue. Mounting the pod links on the underside of the mount will make the rear steer into as it rolls. The unique pod design on the stj provides less weight transfer and thus requires softer front springs to generate enough roll in low speed sections.
I am still lacking the forward bite on carpet of a levered t-bar car but it is now on par with any spring car I have seen. The forward bite issue seems limited to higher grip conditions where a sprung t-bar can load up and lunge the car forward improving acceleration. Next time out I will try pitching the entire pod to see if I launch it better but without some sort of spring device to load i think its unlikely i'll be able to match t-bar acceleration.
Your buddy with the 104 should try increasing his static caster and shimming the front of his upper arm to induce a negative reactive caster effect. On my 104 link car i run 6-8deg static w/ 3-5mm shim on the camber plate. On the t-bar car I run 8-12deg caster with 5-6mm camber plate shim. The extra caster helps with the inherent on power push and the negative reactive helps keep steering from washing out mid corner.
Where is your f1 relative to the 17.5 & 21.5 sedans?
How cold is it there? From the video it looks like most of the field was lacking sufficient front tire grip, how do the soft fronts work?
It also looks as though you did not have enough ackerman in your car the slip angle through the infield is off contributing to the front washing out mid corner.
you will want to place your servo in the car with the links sufficiently swept back at neutral so that the inside link is straight across the chassis at full lock. Adjust the bumpsteer to your preference, raising the link at the horn will mellow steering response and help with exit steering. lowering the horn mount will make the car turn in better with a more aggressive feel.
The 2 biggest improvements I made to resolve my mid corner / on power push was to mount the rear pod links on the underside shimmed down 2mm and use very soft front spings like a tamiya silver or ride blue. Mounting the pod links on the underside of the mount will make the rear steer into as it rolls. The unique pod design on the stj provides less weight transfer and thus requires softer front springs to generate enough roll in low speed sections.
I am still lacking the forward bite on carpet of a levered t-bar car but it is now on par with any spring car I have seen. The forward bite issue seems limited to higher grip conditions where a sprung t-bar can load up and lunge the car forward improving acceleration. Next time out I will try pitching the entire pod to see if I launch it better but without some sort of spring device to load i think its unlikely i'll be able to match t-bar acceleration.
Your buddy with the 104 should try increasing his static caster and shimming the front of his upper arm to induce a negative reactive caster effect. On my 104 link car i run 6-8deg static w/ 3-5mm shim on the camber plate. On the t-bar car I run 8-12deg caster with 5-6mm camber plate shim. The extra caster helps with the inherent on power push and the negative reactive helps keep steering from washing out mid corner.
Where is your f1 relative to the 17.5 & 21.5 sedans?
Haven't tried soft fronts yet, Beth has mentioned that she may try them next week, along with keeping the servo mounted forwards - something I need to do myself.
When you say "raising/lowering" the link on the horn, does that mean towards the servo horn or towards the chassis?
i.e If I used longer spacers between the servo horn, and the ball studs, would that have the effect of mellowing the steering, and improving corner exit, or is it the opposite? Which is what I am trying to achieve as the car turns into the corners quite well.
I also have on order a set of tamiya front springs on order, which should arrive sometime next week, so I'll have to stick with the stock ones for now.
With what you've suggested above, that gives Beth & I something to try out, and work on to improve the corner exit steering on the cars. I was just happy on the night to get my car working without it wanting to lose rear grip on every corner.
At a recent outdoor event on a high grip surface, our f1 cars were around the pace of mid field "A group" 21.5 touring cars, I'm not sure where our cars were on the night of the video above.
Thanks for all your help, and hopefully we can return & share more positive results.
Rob.
02-01-2015, 06:18 PM
#280
Oops, had a look at my car over the weekend and I didn't have the servo far enough forward by 2mm, so I now have it at 32.5mm per Ludo's and Hara's setup. I will leave it with 5deg caster for next Friday.
I also installed a set of Tamiya gold springs, which are slightly softer than the Kit springs, but if I get time will also try the silver springs.
I don't think any extra toe out will help, this will only help with initial turn in, and will reduce the angle of the outside wheel.
Its too long between Fridays
Only running 2 cars this week should allow me to get some more setup work done....
I also installed a set of Tamiya gold springs, which are slightly softer than the Kit springs, but if I get time will also try the silver springs.
I don't think any extra toe out will help, this will only help with initial turn in, and will reduce the angle of the outside wheel.
Its too long between Fridays
Only running 2 cars this week should allow me to get some more setup work done....
02-01-2015, 10:26 PM
#281
Oops, had a look at my car over the weekend and I didn't have the servo far enough forward by 2mm, so I now have it at 32.5mm per Ludo's and Hara's setup. I will leave it with 5deg caster for next Friday.
I also installed a set of Tamiya gold springs, which are slightly softer than the Kit springs, but if I get time will also try the silver springs.
I don't think any extra toe out will help, this will only help with initial turn in, and will reduce the angle of the outside wheel.
Its too long between Fridays
Only running 2 cars this week should allow me to get some more setup work done....
I also installed a set of Tamiya gold springs, which are slightly softer than the Kit springs, but if I get time will also try the silver springs.
I don't think any extra toe out will help, this will only help with initial turn in, and will reduce the angle of the outside wheel.
Its too long between Fridays
Only running 2 cars this week should allow me to get some more setup work done....
I got my 3 Racing F103 front end kit in the mail today (it's destined for my 3 Racing F113), it also comes with 3 sets of front springs, which look about the same size as the Tamiya ones, not sure which are the softest though.
You're right Beth, and having a finite amount of practice time doesn't help either, that's why one of the many reason I help to setup, is that it means we get the track down sooner for everyone to practice on.
Will be interesting to see which one of my F1's will be quicker on the track, will it be the F113/F103 hybrid, or the Street Jam?
Rob.
02-02-2015, 05:02 AM
#284
would this help in a foam tire car on carpet?
02-02-2015, 05:07 AM
#285
Rob,
How cold is it there? From the video it looks like most of the field was lacking sufficient front tire grip, how do the soft fronts work?
It also looks as though you did not have enough ackerman in your car the slip angle through the infield is off contributing to the front washing out mid corner.
you will want to place your servo in the car with the links sufficiently swept back at neutral so that the inside link is straight across the chassis at full lock. Adjust the bumpsteer to your preference, raising the link at the horn will mellow steering response and help with exit steering. lowering the horn mount will make the car turn in better with a more aggressive feel.
The 2 biggest improvements I made to resolve my mid corner / on power push was to mount the rear pod links on the underside shimmed down 2mm and use very soft front spings like a tamiya silver or ride blue. Mounting the pod links on the underside of the mount will make the rear steer into as it rolls. The unique pod design on the stj provides less weight transfer and thus requires softer front springs to generate enough roll in low speed sections.
I am still lacking the forward bite on carpet of a levered t-bar car but it is now on par with any spring car I have seen. The forward bite issue seems limited to higher grip conditions where a sprung t-bar can load up and lunge the car forward improving acceleration. Next time out I will try pitching the entire pod to see if I launch it better but without some sort of spring device to load i think its unlikely i'll be able to match t-bar acceleration.
Your buddy with the 104 should try increasing his static caster and shimming the front of his upper arm to induce a negative reactive caster effect. On my 104 link car i run 6-8deg static w/ 3-5mm shim on the camber plate. On the t-bar car I run 8-12deg caster with 5-6mm camber plate shim. The extra caster helps with the inherent on power push and the negative reactive helps keep steering from washing out mid corner.
Where is your f1 relative to the 17.5 & 21.5 sedans?
How cold is it there? From the video it looks like most of the field was lacking sufficient front tire grip, how do the soft fronts work?
It also looks as though you did not have enough ackerman in your car the slip angle through the infield is off contributing to the front washing out mid corner.
you will want to place your servo in the car with the links sufficiently swept back at neutral so that the inside link is straight across the chassis at full lock. Adjust the bumpsteer to your preference, raising the link at the horn will mellow steering response and help with exit steering. lowering the horn mount will make the car turn in better with a more aggressive feel.
The 2 biggest improvements I made to resolve my mid corner / on power push was to mount the rear pod links on the underside shimmed down 2mm and use very soft front spings like a tamiya silver or ride blue. Mounting the pod links on the underside of the mount will make the rear steer into as it rolls. The unique pod design on the stj provides less weight transfer and thus requires softer front springs to generate enough roll in low speed sections.
I am still lacking the forward bite on carpet of a levered t-bar car but it is now on par with any spring car I have seen. The forward bite issue seems limited to higher grip conditions where a sprung t-bar can load up and lunge the car forward improving acceleration. Next time out I will try pitching the entire pod to see if I launch it better but without some sort of spring device to load i think its unlikely i'll be able to match t-bar acceleration.
Your buddy with the 104 should try increasing his static caster and shimming the front of his upper arm to induce a negative reactive caster effect. On my 104 link car i run 6-8deg static w/ 3-5mm shim on the camber plate. On the t-bar car I run 8-12deg caster with 5-6mm camber plate shim. The extra caster helps with the inherent on power push and the negative reactive helps keep steering from washing out mid corner.
Where is your f1 relative to the 17.5 & 21.5 sedans?