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This may be one of those loaded questions but how do you know what compound and host to run? The compound aint as hard of a choice as the host. I'm running a WCM sportsman if that makes a difference.
 

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In March I asked how to store the tires for the winter..

I never got an answer. from anyone.

Some fast guys say to use the softest hosts you can live with.
others say to use the Hardest Hosts to make the caps last longer.
I know that soft hosts will shorten caps life, by allot.

C4 is for cool tracks.
405 is for warm tracks
C5 is for almost Hot tracks
407 is for anyones guess
410 is for Hot and real hot tracks.

that is the Best that I know. but I am NOT a fast guy.
 

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At MPR where I race the track temp is very cold 40-50 degrees when we start racing in April so I use L10 with soft host on the left sides as the temp warms up I start to try L10 on front and L20 on rear. I keep changing up to L30 as the temp goes up to a temp of 135-145 degrees. I change Front and Rear compound on the left side to change the grip we are looking for in the car. I as a rule only run a extra firm 410 on the RR...

Dave D
TEAM ORANGE
QSAC #821
 

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Buy tires with all host you can help the car with different host also look at your track and surface the higher banked track needs a little harder host and a harder compound 405 410 and l2o or 30 on left if ya wana save some $ buy med host but the more selection you have you will be better off hope this helps alittle .
 

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As you can see.

the tires we use are a BLACK ART

and NO ONE will Tell anything about them.

not ever how to store them. use them.

L10 are for cooler tracks
L20 most all the time
L30 real HOT track.

Rear Stagger is another one...

that is HOW and WHY the fast guys stay fast. and all the others are NOT. and they wonder WHY "GN" is dead.

and by the way I NEVER got an answer why you need $600.00 in tires to race these things. a question posted over 6 months ago. just that you don't
 

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Chuck, there are no simple answers when it comes to tire selection and that is why you don’t get responses. The track you are running, the track temperature, the amount of rubber on the track, the amount of dirt on the track, the class of car you are running, 8.5 vs 10.5, the lap times you are running, the length of the race, the expected number of green flag laps within a race, the weight of your individual car, the set-up on your car, the body type on your car, the body position on your car, and your driving ability all play into selecting the correct tire combination for you. With all of these variables in play, advice is hard to give and others can only tell you what works for them.

My #1 Best Advice: You must use a tire temp gage religiously. Track owners should not allow cars on the track unless the car owner proves they have a temp gage in their pit and they know how to use it. Yes I am serious. If you don’t have a temp gage and don’t plan on buying one, you are XXXXED and there is very little that can be done to help you.

Here is what works for me (generally) and there are 100’s of exceptions:

Left Side:
L10/Soft Host Good up to 110 F.
L20/Soft Host Good up to 120 F.
L30/Soft Host Good up to ?

Example of an “exception”: At the last NCS at Algona (low banked/slow short track) my car would come off the track with the Left Side tires in the 115-118 range after a long run. The car lacked consistent forward bite and just did not like the L20 on the LR. I switched to an L10 and the car was much better. The L10 didn’t grain-up or show excessive wear so that’s what I ran the rest of the event. On a side note; I had several drivers come up to me during the weekend describing the same handling problem that I had. My response was to ask them what tires/stagger they had and then suggest they try what I had. The follow-up responses I got that weekend were mostly positive but other times I can only shake my head when the guy that came to me for advice starts arguing with me on why that won’t work. Chuck, are you that type of guy?

Another “exception”: Sometimes you can switch to a harder or softer left side tire by using an old tire versus a new tire of the same compound. I have left side tires from 2004 that I still run.

Yet another “exception”: I like to run a L30 on the LF whenever possible. For me, I like a car that starts a little tight and then gets faster on long green flag runs. Plus the L30 lasts way longer. If I see signs that the LF is glazing over and not working at all, and the car is too tight, I will then switch to an L20. I typically only use a L10 on the LF for time trials.


Right Side:
96 Firm on Right Front
96Z Firm on Right Front if car is very tight and I can’t fix it.

C4 Soft Host – Short/slow tracks with very low tire temps. Good for parking lot races.
C4 Medium Host – Short/slow tracks with low tire temps. Sometimes use for time trials in place of 405 or 410.
405 Medium/Soft Host – Short/slow tracks with med/high tire temps. (Veteran’s Park)
405 Medium Host – High banked/fast tracks with med tire temps.
410 Medium Host – High banked/fast tracks and/or with med/high tire temps. (MPR, LPR)
410 Medium Firm Host – High banked fast track with high tire temps. (Hideaway, Freddies)
C5 Medium/Soft Host – This tire is the oddball of the bunch. It acts like it’s between a C4 and 405 but the rubber is different. Tire likes to run Hot, but track must be smooth/slick/dusty to hold up. Sometimes its interchangeable with a 405 or 410 sometimes not. (Boulder City)


Note on hosts: Soft/Medium Soft/Medium/Medium Firm/Firm is a subjective judgment call when the tire is built. Even if you purchase every tire with a medium host, they will all be a little different after they have been run in.

Stagger: Give the car what it wants to have the correct balance of turn-in and drive off…this could be anywhere between 5/8” - 1 3/8”. There is no correct answer.

Camber: Other than tire selction, this is the most important adjustment on the car. No two tires are exactly the same and thus every tire needs to be individually tuned for camber (temp) after its been put on the car. A tiny camber adjustment on each tire is often the difference between winning and being junk.

Good Luck!
 

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A black art? Not really but it does take some experimenting and what works for one might not necessarily work for someone else.

Here is what I run and why.

Early and late in the season at LPR, air temps below 80 and track temp below 100* will be 96f-96xf on the RF, this will be depending on how the track is and how the car is going in, if I need more aggressive I will go with the softer host.

Left side tires are L20's with medium host on the front and if the track is really cool, <80 probably a soft LR host just to get the bite coming up off the corner.

RR 405 with a medium host. I have tried the "C" series tires and just do not like the way they feel. I have run that 405 on the track with temps over 100* with good results too.

Now this time of year the left sides go to L30's. If the track temps are up and you are graining the LR and it is a L20, change it to a L30 and that problem will go away. Stay with the same host and size.

During this time of year the RR is a 410mf, gotta have that here in Alabama with track temps of 150*+.

You will notice, I am sure, I did not mention what host I am running on the L30's. That is not because it is a secret or anything,but because I am trying softs and mediums with about the same results.

Keep these things in mind when buying tires.

If at all possible, say if you mainly run at one track. Stick to one tire size for all four corners. For example, for the LF always order 18" and the same for the RF. for the RR 18.5" and the LR 17.5". Order say a 17.25" LR so you adjust for RR tire wear without having to have 100 tires to choose from.

Now you have a standard, make your car work with these sizes, YES it can be done. You do NOT, I repeat DO NOT have to have every size imaginable to be competitive or to even win.

I got that tip from a good friend and fellow racer, Jerry Evans. He can vouch that I am hard headed to say the least and had I listened I would have probably saved a ton of money. :D I buy ONE size front tires, the left and right are the same size. ONE size RR and one size LR. The smaller LR I have and only run occasionally, so they do not wear much at all.

Another thing you can do is keep en eye on the tires as they soften, when they do, mark them and save them for those cooler days and you won't necessarily have to buy the softer compounds.

TEMPS TEMPS TEMPS, keep an eye on these. This is the number one KILLER of tires, if you run the edges hot you can really kill a tire quickly. Also if the car is sliding, pushing or loose, don't continue to run it thinking it is going to fix itself. I have NEVER seen a race car, of any type, miraculously repair itself and become a rocket.

Rear stagger more=looser, less=tighter. This is a general rule of thumb given that all things stay the same.

Don't get caught up in needing 1/16" difference in stagger or even an 1/8", you can adjust for those things with other settings on the car.

Now before any of you guru's out there, or even the guys that know me and have seen the assortment of tires in my trailer begin to say, "yeah but..." keep in mind that the purpose of this post is to HELP fellow racers gain some understanding on how things work and why.

All this being said, the "fast" guys at your track should be able to help you decide what you need and when, if they are not willing of don't take the time THEN SHAME ON THEM.:(

I know I go out of the way to answer questions from my fellow racers and usually give them way too much information. Of course there are those guys that no matter what you tell them they do not listen, that is out of my control.

Hopefully this will help a little, of course then again I may not know what the heck I am talking about. :D
 

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Thank You FastScott., and ScottH.

this is the most information I have received about tires in 3 1/2 years of racing 1/4 scale.

I have a $75.00 temp gun. have from the beginning.

with this information. it is back to the statement.
$600.00 in tires.

my basic setup on tires
Right Front 96 xf and 96z
left front L20 two sizes
left rear L20 three sizes
right rear 405 firm, C5 firm, 407 Firm
10 tires, and still need more. each year. and I run at the back. OH 8.5 sportsman, at Freddie's.
and I am told m\by many. More testing, more practice. more testing.

but the key is... No 2 tires are the SAME. EVER!!!!!!!!!!


always changing temperature of track
always different tires and reaction to track temperature
as tires are used they change hardness and grip.

So I need about $800.00 for tires
and $200 for extra practice days at track
and 60-100 for racing fuel and oil.
beside racing every Saturday.

beside needing a New car, I should locate $2,000 to race next year.

And everyone Says 1/4 scale is the Cheapest form of R/C racing...REALLY?

OH I am 60 years old. raced R/C for 22 years. mostly electric 10 pan car.
My winning days are OVER. and No big deal. but I dislike being 1 and 2 laps down in a 35 lap heat race.

while I am hard headed.. If you tell me something. explain it. don't just tell me.
without explaining, I will not believe you are telling me the truth.
 

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I think my tire bill for last year, my first full season was about $600, maybe and that was starting from scratch. I also have SEVERAL tires I am still running.

I would easily spend $350 on tires for one pan-car race and I raced that a lot. So yeah, 1/4 scale is way cheaper.

I am not sure of the exact issue as far as why you are getting lapped in 35 laps but I dare say it is not just tires. Not to say that it may not be part of the issue, but is not JUST the issue.

Allow me to ask this, on new tires are you up front?

If lap times at Freddies are 6.6-6.8 and you are getting lapped inside of 35 laps, that means you are at least .2/second per lap off, maybe even closer to .3/second per lap. Not having ever been to the track but knowing a little about racing, I would dare say it is more than tires.

What is one of the "fast guys" drives the car. Are they faster with it that you are?

Does the car roll the center of the corner or does it hit "the wall" when it turns. Not literally, what I mean is does it slow down in the corner. Does the car have forward bite? Are you waiting on the car to turn? Is it loose on entry or exit?

Where are the faster cars passing you? Corner entry, middle of the corner or exit? If your answer to this is down the straight, it is still because of corner speed.

All of these questions must be addressed to get the car fast. If you get the car to rotate through the corner, the straights will take care of themselves.

Remember this, there are FOUR corners and TWO straights. Where do you want to be fastest?
 

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I truly do thank you for the info and help.

there are 5-6 cars at 6.6 and most of the others are 6.9 at best. and I am one of the 6.9 at best.
Yes I know being passed down the straight is from a slowing down in the turn for some reason.

So yes being slower by .3 and more per lap, will put you down a lap in 20 laps easy.

The fast cars and the slower cars DO run together. so allowing the faster cars to go pass will also slow my car down .7 or more and do that for 3 or 4 fast cars puts you down a second lap.
I am NOT ASKING for any kind of rule change, of any kind.

and to add.. 2 years ago GN was running 6.6 at best, with the same drivers.

Just some OLD GUY (me) trying to keep racing.


P.S. I have over 20 tires that have 50 percent or more of cap rubber with the HOSTS VERY SOFT and can not use them. so this is not a new problem.
 

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tires ARE a black art. and everyday it seems to be different. so giving advice is kind of crazy.....because its just based on experiance and feel.
if you race at the same track you don't need a ton of tires.. you know what works most of the time and different different RR compounds for when track wants something else to keep running the speeds you know you can do.

its only when you travel do you start running up the cost of tires because you don't know what you might need there. but you could just run what you have and do the best you can with that. its all in what your willing or can do to race.

for regular weekly racing you know what RR works more or less. get some different left sides for stagger choices..or if your RR gets smaller you can keep the same stagger. and they last alot longer then Rights so that the one to buy for different sizes.. heat gun will tell you alot in how the car is
running... some think the chassis is wacked when they are just really off on camber.. or if heat is good across tire then perhaps your really are wacked on the setup. a tool i use all day long.

winter storage. bring them in the house when your done racing in fall.
and don't bring them out until your ready to start that spring.
i store mine in basement.
 

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P.S. I have over 20 tires that have 50 percent or more of cap rubber with the HOSTS VERY SOFT and can not use them. so this is not a new problem.
Let me guess they are RF tires.

I have had that trouble and spent a lot of time on it and talking with Todd. Who BTW is very helpful. If this is the case, then Todd's suggestion is to go up in host firmness. Me, I worked on the setup some so it would turn in just as good but not abuse the RF as much. It worked, last race day track was over 150* and the RF on the car was from 2011 and held up all day and is still a good tire.

I will say this, if you have what I will call a "tire" setup chassis. Then yes you are going to go through tires very quickly. If you have more of a "suspension" setup, the car will be fast and easier on tires to boot. This is truly where the "magic" is, it is also where the fun is for me. I am a setup freak, I get a real kick out of trying stuff, figuring out the hows and whys and putting it all together.

I still do not think of them as a "black art". Is there a level of knowledge that needs to be gained to get the most out of both wear and speed, well sure, but it is something that can be gained by taking notes and paying attention. If you make a change, don't go out for a fuel tank, go out for just 10-15 laps and take some temps, see/learn what the change did.



Now if you want to talk "black art", how about tuned pipes, port polish and port timing. :wave:
 

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As the HOST going soft.

96, C5, L20.

it does not matter where on the car the tire sets. they all go soft and then the car becomes un-driveable. if on the front the car get very LOOSE and on the rear the car just spins.

I am asking for this help for 2 reasons.

For Me.
and in the last 3 years I have seen many buy cars and come race and after 5-10 races, these new racers STOP coming to the track to race.
and the cars do not show up for sale ether. WHY.

I know times are hard. My wife has been out of work for 2 1/2 years. but I still get to race most weeks. as cheaply as possible. but still race.
 

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Why does the host go soft?

Heat. The heat changes, or softens the host. Why? Beats me. This is something we have dealt with in Pan car as well.

This I do know, if you keep the tires as cool as possible, then they will not do this. The only tire I have had this happen to, that has caused significant ill handling qualities in the car is the RF. I have a few of those that have great rubber on them and the host is dead. I am going to try a XXF RF and see how that goes. I don't think I have worn out a LF yet and only one or two LR. By wearing out I mean the size. I have not had any ot these have a host problem.

Just out of curiosity what kind of tire temps are you seeing on your car?
 
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