Formula Atlantic slicks - experience/opinions?

[Lane]

I recall reading references here and there to Formula Atlantic slicks. Who runs them? Thoughts/opinions? Is the performance that far above a Hoosier A6?

Thanks,
Lane

[MadMaxAtom]

I run them. Have been for years. I have set a couple of track records on them and I think it is THE tire to run on the Atom, IF you want the MAX traction.(hehe..)
Yes,superior to the Hoosier A6 and the new A7s.(yes,I have run them) The Hoosier FA r25b has proven to be the best tire I have found,bar none.(and I have tried many..)
The Hoosier R25b compound is very sticky and likes track temps in the 70-100 degree range,but are useable down to 45 degrees.Less than that you are wasting your time.
I run 9.5x23x15 frt and 12 or 13.50 x23.5x15 rears.
You need to run proper width wheels. I run 10" wide fronts and 13.5" wide rears (I like the Keizer 3 piece wheels and have never bent one,and yes,they are expensive..but they are the best for the money)

Your car needs to be set up to take full advantage of them..you will not get full grip without a proper setup.
They like heavy spring rates..350lb fronts and 550lb rears,and shock valving to match.(not just cranked up settings)
If you run the suspension too soft,the tire patch will not stay in contact with the track due to the Atoms suspension geometry.It just doesn't work. Simple as that.
The negative camber needs to be proper for your ride height or you will cord an edge quickly.This is done mostly by trial and error,but a good starting point is -2.5 for the front and -3 for the rears.
Watch tire wear rather than just tire temps.Yes,I know..temperatures are important but it is not the only factor in determining proper suspension settings.
This I have learned: improperly recorded tire temps (doing them by yourself, or not doing them HOT) will mislead you….but the tire wear pattern NEVER lies..! Some may not agree, but that's fine. My way works for me.
I run my Atom ride height with the control arms set parallel to the ground.This is more important than getting it as low as possible as it puts the suspension in the "sweet" spot of its travel. Trial and error has proven this out for me.
I like about 1/6" toe IN up front and zero toe, in the back. Tires wear well and car is not nervous at speeds over 100mph.

I usually get my FA r25bs as scrub take-offs from a guy in NY who handles race tires. Best part..a set cost me under $300,shipped. Yes, $300 for 4 uber-sticky tires. You can't even buy one new A7 for that money. Occasionally, Hoosier puts NEW ones on sale for $450/set..with free shipping. The R25b's will last a long time on a car set up properly. My first few rears I went through quickly learning how to set the car suspension and correct air pressures.(cold,18 front/25 rear) Once I had the magic formula (pun intended) the tires wear incredibly well. I can get 15-20 events out of a set of rears, and the fronts will heat cycle out before you wear them out.

Important for MAX tire grip and life with R25bs: Don't leave your spare race tires out in the sun! (Cover them or put them in the trailer) Don't subject them to temperatures below 45 degrees. Flip your tires when they start to show any shoulder (edge) wear. ( I usually flip the rears every 4 events,fronts every 6)

Seat time!! You will need to learn to drive the FA R25Bs. They are a soft side walled tire, and the car does move around on them a bit,but they are not sliding. You will need to learn to trust this feeling. They do not like to be shocked. (hard inputs from steering,brakes or throttle) They do not like to be really slid around on purpose, (forced rotations etc) but are quite controllable if sliding, once you really understand what is happening and what they are doing. Slow imputs are rewarded.

Make sure you brake bias is properly set as well. The setup I use is heavily biased to REAR brakes. If you are locking your front tires,you have too much front bias. Period. Take advantage of all that fat sticky rubber back there and adjust your bias to juuust about lock up the rear tires on heavy braking and you will be amazed how nicely the Atom will trail brake or threshold brake. It really is very different than most cars needs. My bias is about 30frt/70 rear. It works.

You will need to anticipate rather than react to what is happening.The tire needs to be fully loaded with finesse, or it will not hold,and it will wear fast!

There is a learning curve..and you either learn it or you will get no benefit from the tire. It's as simple as that.

They will NOT make you Superman (or Wonderwoman..) overnight. Once you feel the grip they offer, you will never want less..

Seat time is your best friend!!

All this information is true,and tested in the real world,by me personally,for many years and laps.

I have official recorded track times (and trophies) to prove it..

I'll bet you're sorry you asked…

[Chris McCarthy]

MMA,

I need a new set of tires and have two sets of stock wheels and a set of r888s laying around. I've only had experience with the R6s that came on my Atom. What would you recommend for someone who drives to track days and spends plenty of time on the street in good weather only. Should I put the r888s on one set and A7s on the other or....?

[MadMaxAtom]

A7's are about the stickiest tire going short of a full race tire..however Hoosier really doesn't want them used for street use.Yes,they are DOT rated..but still not up to street safety standards. That being said..I'd have to say stay with the 888s for street/track use. Yes, they are a compromise..but there really is NO tire built to take full advantage of track conditions and be safe for street use.

[RyanD]

I run Hoosier A6 tires on the street, and they are fantastic. No point having rain tread on a car that will never be driven in the rain.

[MadMaxAtom]

It's not just about rain as an issue for a tire to be street-able. Dirt..sand..oil..branches..lumber..dead (and living) animals..stones..rocks…luggage..etc etc. Any kind of debris. Stuff in the road that can cause an impact,plus holes in the road surface. The Hoosier R compound tires are not designed to take street abuse, as their carcass construction is primarily a race track design,where there is much less tendency to find "stuff" in your path vs. public roads. I've had a small 3/4" stone take out an R7 tire..so I have seen it up close and personal. Yes, stuff can take out any kind of tire..however, there is a reason that tire companies stamp "not for highway use" or "for competition use only" on the sidewalls of their DOT R compound tires...

[RyanD]

I'll take the safety of better traction over the possible risks. The Atom isn't even heavy enough to collapse a flat tire made for a >3000 lb car. If the tire can't handle street use, I sure wouldn't want to race with it.

Remember that the Atom itself is labeled "for off road use only", but that isn't stopping us.

[FourFather]

I lost a brand new Hoosier A6, on its very first session, at Eagles Canyon Raceway, due to a puncture. I was going into a left hand corner, and the right rear deflated almost instantly, putting me off the track.

Turns out I ran over a bit of a broken connecting rod left on track where a new Mustang had kicked the rods out during the previous session.

I think a street rated tire would have survived that incident, like Max is saying.

[RyanD]

Right, the reason it was an issue is that you were probably pulling 1-1.5g's in a corner and the tire flexed. If you had the same puncture driving normally on the street, probably nothing would have happened.

The A6 might be more likely to get a puncture because it picks up everything, but it's not going to be dangerous.

[MadMaxAtom]

I've learned to listen to companies when they tell me not to use a specific product for a purpose it was not designed for. They are usually much smarter than me..or have a lot more experience.

The things I have seen people do in my 45 years of being a mechanic…even after they have been told not to do it..oh the stories I could tell!