300’ drags (275vs295)

Hey guys. 76 regal 455. 3:42. Thought I’d share my story, got new 295/50/15 cooper cobras on 10”wide rims. Was racing the 300’ drags and these tires did nothing but spin spin spin. Spun the whole way down. Swapped back to my 3/4 tread 275/60/15 cooper cobras on 8.5” rims and was a huge difference. Hooked up much better. Long story short anyone wondering this debate The taller tire wins

 

Pics of last night racing dads century

 

So I've got a little experience racing on the Chupacabras, and I'm a big fan of them and I can offer three observations here:

- Fully treaded tires will never hook as well as worn tires, I generally spend a day doing burnouts before I'll even bring a new set to the track. And not surprisingly, fully bald Coopers hook like slicks. Shame you gotta throw them away when theyre just perfect, but if it even sprinkles your car is going ass over bandbox into the guardrails.

- A taller tire in effect kills gear ratio, making it easier to hook but diminishing "60 ft" ability. I generally default to the widest footprint given a preferential height that works best with my gearing (in my case 26.5 in and 3.73 gears)

- tire pressure COUNTS. For me, 23 lbs puts enough of a footprint down while giving some rebound/wrinkle to the sidewall. Be sure to glue the tire to the rim with weatherstrip adhesive though, I have spun a lot of times on the rim, still do to a certain extent. only way to know what works best for your launching surface is to test, a lot. And once your tire is at pressure, re-check.. my tires will heat up to 26-27l bs if I'm not careful.

Good luck, and keep us posted!

 

Thanks for reply, the 295s I bought were on marketplace they weren’t brand brand new, supposedly had 300 miles on them, but more tread than my 275s. And I tried 22psi, 18psi, and 14psi, did quite a few burners, and couldn’t get them to hook anywhere near the 275s. Maybe they were slipping on rim? Guess no way of knowing?

 

To slip on the rim you really need to be planting the tire hard, and that doesnt sound like what was happening. And you can measure that by putting a mark next to the valve stem and keeping an eye on it. All that said though, your testing has shown that the 275's work better with your combo. Thats farther than most people get. Keep at it!!

 

Yeah always room to learn/improve. Going a step further yet, ordering drag radials. Deciding between Nitto 555 r2 or Mickey Thompson et street ss. Both have great reviews. 4.9stars. Nittos being 50$/tire cheaper. One guy reviewed the nittos said they were great but said the MT hooked better.

 

MTs hook much better than the Nittos but I think the Nittos do better in the rain.

 

I have the drag Nittos 305-45-18 on my street/strip car, and notice that when the tire is cold they don't bite at all. But after driven some and they get a little heat they bite real good. Haven't taken them to the track so no experience there. So far I would buy them again.

Fernando

 

The narrower tire has more weight concentrated on the contact patch verses the wider tire?

 

I have the MT DRs 275-50-15 on my 350 GS, they hook great on a prepped track, unprepped track such as Summits Fun Runs where they don’t prep the starting line, I’ll spin like crazy.
My vote is for the MTs

 

Were both tires run on the same day / conditions?

 

Same day same condition yes

 

The more worn tire is what caused the better conditions although there may be a little to the worse effective gear ratio. The MT DR will out hook the Nittos right out of the box but IMO the Nittos are a better tire if you are going to do a lot of street driving with them because I believe they have a slightly stiffer sidewall. The Nittos will get better traction as they wear just like any treaded tire and start to get closer to the MT's