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Technical => Roo Man's Room => Topic started by: hemidakota on March 24, 2016, 08:30:36 PM

Title: Tubes or no tubes in slicks.
Post by: hemidakota on March 24, 2016, 08:30:36 PM
Changing slicks on a FED to a M/T 33x10.5w on a 10" wheel. It had 32x14 with tubes on a 14" wheel. We have struggled with tire shake with the big slicks. Air pressure was very sensitive. It is a mild steel car and is 185". Weighs about 1650lbs with driver and runs in the 7.6's @ 176mph. It leaves at 6200rpm and is a 565 injected alky. I would really like to hear what everyone else does and how it works for them. I like the idea of less weight but is it worth it? Most of the info I find is for a door cars so it does not relate. Thanks for all the help as always.
Title: Re: Tubes or no tubes in slicks.
Post by: Paul New on March 24, 2016, 10:16:21 PM
No tubes! For 7.60's your over tired 12" wide is plenty
Title: Re: Tubes or no tubes in slicks.
Post by: dreracecar on March 25, 2016, 08:07:01 AM
Door car tires are made different then Comp tires, you want to run tires that are for compitition type cars
Title: Re: Tubes or no tubes in slicks.
Post by: masracingtd1167 on March 25, 2016, 01:09:55 PM
You should be just fine without the tubes . Why carry all that extra weight . That 14 inch tire was hurting you . I am seeing a lot more of those 10.5 tires on dragsters lately . The world champ in Comp wit a fed was running a 10.5 tire on his b/nd . I run the 12x31 Goodyears on mine and have thought to my self that they might be a little too big for my car because of my motor placement only 36 inches out . Keep us posted with your results . For me the 22585 Good year has been the best . Second would be the Good year 1288's and last were the Hoosier 12x33 c09 tire witch is very aggressive and hard to get enough wheel speed . 
Title: Re: Tubes or no tubes in slicks.
Post by: George on March 25, 2016, 03:42:13 PM
A BIG amen on the Goodyear 2585 ! I have tried 3 different Hoosiers. The extra weight will slow you down.
Title: Re: Tubes or no tubes in slicks.
Post by: hemidakota on March 25, 2016, 04:00:22 PM
So if you all run no tubes, what kind of air pressure are you running? The M/T guy at the reunion said to start at 8.5 psi. Just trying to get as much info as possible before next weekend. M/T recommends tubes and the tire guy at the track said it will be ok with no tubes. We are used to the 5.5 - 6 psi range on the 14" slicks. Thanks guys....
Title: Re: Tubes or no tubes in slicks.
Post by: Paul New on March 25, 2016, 04:59:28 PM
Jon Hansen at Hayden Ent. is the guy to talk to about the 2585 tires! He could get you headed in the right direction with pressures
Title: Re: Tubes or no tubes in slicks.
Post by: coupemerc on March 25, 2016, 05:19:23 PM
2585 tires and no tubes for me too. In fact, I'm in the process of mounting up a pair right now. Just finished coating the insides with dish washing detergent.
Title: Re: Tubes or no tubes in slicks.
Post by: dreracecar on March 25, 2016, 05:22:10 PM
Jon Hayden is the guy to talk to about the 2585 tires! He could get you headed in the right direction with pressures

   Its Jon Hansen at Haydon ent
Title: Re: Tubes or no tubes in slicks.
Post by: Paul New on March 25, 2016, 05:27:29 PM
Oops yes typed that wrong Jon Hansen

http://www.haydenent.com
Title: Re: Tubes or no tubes in slicks.
Post by: JrFuel Hayden on March 25, 2016, 08:54:27 PM
1'st of all most racers don't know the 10.5 M/T's are designed for 2500 to 3000 lbs door cars. So I think the inner tube suggestions are mainly because of the 16" wide rims.  Now the big reason they are working is they have much stiffer sidewalls. Also higher tire pressures. Mostly the difference is the much lighter weight of dragsters.  Oh Ya, you should not need inner tubes, I don't know of many if any FED that run tubes.
Now, Craig Bourgeois, 2015 NHRA Comp Elim Champ is an interesting combo. 1'st of all the MT tire is 29x10.5Sx15, the code of the size is "S" is stiff, your 33x10.5Wx15, is "W" is wide, which is actually 11" wide, and allot heavier, than the Goodyear D2585 31x12x15 22.6 lb tires. Max wheel width rule in JrFuel and A/ND & B/ND is 12". The Goodyears grow more, because of the MT stiff sidewall tire. Don't get me wrong I have a set of MT 33x10.5x15, I just need to try them, but they are over 10lbs heavier PER tire.  OK now back to Craig's combo, I think he wanted to run a rear gear in-between options because his 12bolt drop-out has allot fewer choices, so he tried the 29" tire. Craig runs 7-7 1/2 # of pressure. Again to back-up the higher pressures recommended, because of the heavy door car difference. Another thing is Craig runs allot more RPM, he tends to run 10,600 rpm high rpm chip, and I think he he runs that at about 1000-1100'. You see Comp elim is all about finish line racing, because no racer wants to hit the index. Craig has one of the faster cars/classes, so he chases most cars, so he has a better idea how hard he needs to beat his competitors. Another idea Craig had is a few years ago is I built a set of 21" wheels, not the normal 17" wheel. It is only an advantage in Comp , full tree, with the increased roll-out, because of the 27.5" tall tire. It multiples the affect with the 2" axle offsets. The 21/27.5" wheel gets you a 4" head start on the start line, but again ONLY in Comp, any heads-up or bracket racing with a Pro Tree = no advantage.
Most 7.60 dragsters I know run either 31x12x15, or 33x12x15 Goodyears or Hoosiers, you may need the 33" tires because you are running 565 ci motor = more torque. Depending on rear gears. But if you are looking for better 60' times, you'll want more gear, and shorter tires. Most all Heritage JrFuelers run the D2585, 31x12x15, a few run 33x12x15 because they have their engines out 52-60" and have less rear static weight. Can JF be all wrong running 6.90's to 7.10's, 185 to 195 mph.

Feel free to call me 805-444-4489 cell
Jon