Rear Tire selection

[up in smoke]

great feedback for us rookies just listening in. I am also a newbie with 6 passes and I am also saddled with the question of what tire, what launch rpm, tranny brake or no-tranny brake,,,ready to hear as much input as possible thanks

[codysisson]

Jon, Thank you for the great feedback! The 7800 Stall converter was a 7", I now have a 9.25" converter that was recommended to me. The fellow who does the converters is in Texas, I am trying to get the name from my transmission guy.

What compound do you recommend for the Good Years? I also want o get another set of rims. I have a set of 10" Sander rims now but I want to have another set of mounted tires for back up. Where do you recommend I buy a set?

Oh I forgot to mention like you pointed out Jon, The MT's are very heavy compared to my Hoosiers!!

[George]

Compare the weights of the tires and it's clear. The 2585 is designed as a light weight grow tire .

[dreracecar]

FYI---Tires that come in a group that includes .5 numbers for tread are mostly door car super classes and do not grow whereas solid numbers are comp tires and do grow, plus they tend to GET-UP on the tire quicker

[JrFuel Hayden]

Cody, I think you should try your friends 12" GY, and if they work better call me, 805-444-4489 I'll put you on the list for D2585, & I recommend starting with your 10" rims at 6 lbs of pressure, and go down on pressure [ 5.75 - 5.5] if you are hooking up too much, and want more tire speed, and up if you want more traction [6.25-6.5].
I wonder if your 9.5" converter is too big, the only FED car I know that is using a 9.5 is a blown alky late Hemi A/FD, and he's making at least double the HP you are. My guess is your 9.5 will pull your motor down below your HP range. A good idea is ask your engine and/ or cam guy to find out your RPM range, and get your converter to work in that range. As an example, if your motor starts making power at 5000, but your converter stalls at 4000, your combo will struggle for 1000 rpm. The biggest increase in our JrFueler came when we changed converters. When you change to a bigger cam and/or more compression, you may have to change your converter stall [ flash point]. Which means you may not have to get another converter, just have a converter guy change the stator. I have changed at least 4 stators, after changing my motor combo's ie cam, heads, compression. 

Jon

[dusterdave173]

Up in Smoke
I hear ya--don't worry just keep on and experiment--Mt car will yank the spit out of your mouth leaving at 4000 but I have toned it way down on the leave  RPM until I get more seat time--the car really has multiple personalities depending on launch RPM, tire pressure, wheelie bar height etc  I also have a very loose converter that gives the car more 'range" It does pretty well no matter what--I am thinking a tighter converter would not be so good--I bought this one on a gamble but it has turned out fine.
My car does seem to pick up wheel speed with less tire pressure--I can lower it enough to haze the tires on leave--Everyone around me acts like I am crazy when I had 9-11 lbs in them but it sure did hook!!!!
My car also seems to like more weight on the nose so.....It is all a balancing act--check back about Labor day and I will know more
Keep records--have someone that knows what to watch keep an eye on every run--the REPLAY XD MINI video camera is less tha $140 delivered and is EASY AS PIE to use--big help!!!

[masracingtd1167]

While we are talking about tires I guess Jon might be able to answer this question . How much do you think that 2585 tire grows at 180 to 190 mph ? I am thinking about changing my rear gear from a 4.56 to a 4.88 . Right now I am crossing about 8700 at 182 and I think I should be crossing a little higher . Raising the shift from 8800 to 9000 picked the car up about .03 so I am thinking the gear change might help . I am still using a 1.80 first gear and thinking of going to a 1.69 . My 60 ft's are around 1.05 1.06 .Thanks Bill     

[Roger]

Hi Bill, what size tires are you running to get those numbers?

[masracingtd1167]

Roger I am using the Goodyear 2585 tire 12x31 . My combination is a little different than most . My motor is a 394 cube smallblock with an old set of 18 degree Comp eliminator heads . I run a pair of Rons terminator 's on a sheet metal manifold . It's a little different but pretty quick and I an allways trying to make it quicker !

[Compsix]

If anyone is interested we have a set of 31x12x15 hoosiers that we have two runs on and then decided to go a different direction with our tires. 

$400 you pay the ride.... 

[up in smoke]

anyone out there ever try the hoosier 33x12-15 pt # 18350?

[George]

Should anyone find a tire for an injected Alky FED that will out perform the Goodyear 2585 after a comparison please post some info. Thanks.

[JakeB23]

After talking to slick manufactures and some racers that pointed out all the 10.5 tires are designed for the 10.5 door car classes. So I think the biggest difference in those tires is a lot stiffer sidewalls to handle 3000+ lb door cars and softer compound to work with "dead-hook, shift, dead-hook, shift," etc.

I've never seen a 10.5 outlaw door car "dead hook"  From my observation it's a controlled spin for the duration of the run.

Do you care to expand on this?

I have a couple of questions, and I don't want to hi-jack the post, but here goes.

Disclaimer, I am known as an over thinker, and I don't want to be a smarty pants, but I am always curious.

There are a couple of JR. Fuel, Heritage, 4.99 minimum dial in racers on here, and there are also some bracket racers/nostalgia index racers that aren't concerned about the fastest ET, but more consistency and running the dial.

So here goes.  First, I see some opinions about "tire growth"  but why do you really want a tire to grow?  they way I see it, the more it grows, the less chance you have of having a flat contact patch?  Wouldn't centrifugal force push the center out?  Yes, I know NHRA top fuelers do this, but, they also have a huge wing. 

Second, I don't exactly understand the big deal about tire weight? I seen on Jegs the 10.5 mickeys were 33 lbs and the 32 12 hoosier's (D05) are 28lbs.  Yes, I know 5 pounds a tire is big when ET is in line, but if running an index or bracket, what does 5 pounds really matter?

Third, it seems that everyone wants their FED/Altered to "get up on the tire quick" and "wheel speed is king" Why wouldn't a stiff sidewall work here?

Just curious, not to be smart, all opinions welcome

Fire Away!

[dusterdave173]

Can't answer any of that but my 10.5 MT will spin with lower pressure and dead nut hook the slober out of your mouth at higher pressures  that is the exact opposite of what that tire has done on my past door cars FWIW .
The dragster is way different in lots of ways--it really digs crazy loose converter--my door cars did not
The math for lower weight on rotating parts will astound you at the performance diff it Should make--I am like you --doing this for fun so who cares but...real racers pee before a run and take the spare change out of their pockets

[masracingtd1167]

anyone out there ever try the hoosier 33x12-15 pt # 18350?

   I have used that tire on my car and it is a pretty good tire . It is a little more aggresive than the Goodyear and a little heavier . I think it is a good option for those who can't get the Goodyear . I plan on trying them again on my car at some point .Bill