Today I went to the track to run my first time on my drag radials. The tires are 255/50/16's BFG's. My 60' times wher 2.2's or higher all day. 1/4 times of 15.2 to 15.4 at speeds no better than 88 mph. I put my street tires 235/60/15's off brand tire that are on thier last leg and run a 15.07 @90.1 mph with a 60' of 2.14. To back it up I ran one more at 15.11 @ 89.6 mph 60' of 2.16. What am I doing wrong? I do a 10 sec burnout on the DR's at a 19 PSI. Street tires are at 30 psi.

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87 Z28 305 TPI, Auto, LT-1 cam (@.50 418/430, 194/199, LSA 111), roller timing set, 2.73, Gutted air boxes, K & N fillters, Dyno Max 3" cat back, 8.8 mm spirals, air foil, BFG Drag radials, and 170* Stat.
Old Best 15.414 @ 87.47.
new best 15.006 @ 89.55.

“Fallen But Not Forgotten”

 

just raise the air pressure in the dr's. if you can hook that good on street tires then you can easily run more air on good tires. if the pressure is too low for the car to push through it creates rolling resistance.
anytime you are setting up a car for best performance, always run as much air as you cna get away with. hell i run my hoosiers at 27psi usually.

lata
tim

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91 Camaro RS-LO3,Auto.
14.209@95.46mph
Best 60' 1.917
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There goes that light builb in my head.

 

Like NJ said, run them with more air. I run
my BFG's with 26 psi.

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Tom K.
84 Z-28 M5 305 L69 HO
pulleys,coil,3:73(stock)
Jet chip, fan switch,
Al dshaft,1.6 rockers,
LCAs and brackets,BFG DRs
14.20 @ 96.74 2.02 60ft

 

You can't just guess at the best air pressure. I've heard that the drag radials work best at 20 psi but each cars suspension is set up different. Start with 25 psi and drop 1/2 pound at a time untill you get the best 60 foor time.

Street tires will always work good with 32-35 psi since the radial wall construction doesn't let the sidewalls roll over when the pressure is low. Instead the center of the tire rolls up and you only have contact on the outer edges of the tire.

Drag radials are similar in design but allow lower pressures. Personally I don't see any benifit to drag radials unless you run in a class that requires a radial tire. If you're already changing tires at the track then just buy some MT ET Drag or ET street tires.

I usually run my ET drags at 16 psi. Heavier cars also require more air pressure.

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Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z Pro ET Bracket Race Car
383 stroker (carbed) with double hump cast iron heads and pump gas
461 Big Block installed and ready for the 2001 racing season

Best results before the 383 blew up
Best ET on a time slip: 11.857 altitude corrected to 11.163
Best MPH on a time slip: 117.87 altitude corrected to 126.10
Altitude corrected rear wheel HP based on power to weight ratio: 476.5
Best 60 foot: 1.662

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley

 

I couldnt beat the price for the drag radials. 90 bucks for the set only made 5 runs.

 

HEy Stephen ,

What would you suggest if the car will be driven with the same tire to race?(about 100 mile ride)

Daz

 

I wouldn't suggest anything. A street tire is for the street. Running any kind of drag tire on the street must mean you have a lot of money to spend. Streets and roads are bad for any type of tire. Rocks, potholes and debris are hard enough on street tires, why damage a drag tire?

DOT drag tires such as ET Street, Drag radial and Nitto's are all designed for cars that run in a DOT tire class. They are designed for the strip, not the street. They just happen to meet minimum DOT requirements.

Excluding the above "good deal" for the drag radials, figure out what they normally cost. Then figure they'll only last about 3000 miles on the street before they're worn out. I got 2 years out of the last set of slicks I had for strip only.

The closest thing you could use for street/strip would be MT Sportsman Pro. They have a good street tread and are soft enough for strip use.

[This message has been edited by Stephen 87 IROC (edited April 21, 2001).]

 

You don't need a 10 sec. burnout for dr's. If u do burnem' for that long u lauch on little ***** of rubber(marble effect). Try burnin out for 3-5 sec. DR's are more like a street tire in the respect that u don't need a long burnout(street tires are just supposed to be spun up for a sec or two).

 

the nitto extreme drags are a good street/strip tire. they have a treadware of 100 i think, the bfg's are a0 compound. they are ok in hte wet and the cold and will hook up nice if you get some heat in them.

lata
tim



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91 Camaro RS-LO3,Auto.
14.209@95.46mph
Best 60' 1.917
Check Out The East Coast F-Body Nationals Home Page
www.geocities.com/njspeeder

My MAFB.ORG Home Page
www.mycar.net/mafb/registry/detail.cfm?id=299

DSI Racing Home Page
www.geocities.com/foff667