Fermin91rs305

Fermin91rs305

AlkyIROC

I always suggest to stuff the tallest tire possible inside the fenders then adjust the gear ratio to compensate for the gear ratio to provide best 1/4 mile performance.

Fermin91rs305

AlkyIROC

The advantage of a slick is traction off the line. Little to no tire spin off the line means quicker 60' times which means quicker ET. The softer rubber compound will grip the pavement better than a radial even with poor track conditions. The downside is slicks will also wear out a lot faster. Drag radials are nice as they have less rolling resistance than a full slick but still have a soft rubber compound and will wear out just as quickly. Even faster if driven on the street.

Buying someones old slicks may seem like a deal but old slicks usually means the oils in the rubber that make the tire sticky when heated up have dried out. You may still have a lot of rubber but if they can't be heated up, they won't get as sticky.

Street tires and radials are designed not to heat up so trying to heat them up in the water box just wears the rubber off and makes them slippery.

Using a 28" tall tire instead of a 26" tall tire is like doing a gear swap. I'm not doing the math but you had 4.10 gears with 26" tall tires. Putting on the 28" tall tires make the car feel like it has 3.73 gears (not accurate but only for example). That means the torque multiplication to the taller tire is decreased making the taller tire less likely to spin off the line. You have a faster ET because you didn't overpower and spin the wheels as much.

How much gear and what size tire depends on your rpm range and what the rpm of the engine is as you cross the finish line. If everything is set up to give the best performance, you should cross the finish line just as the shift light comes on or slightly after the light comes on.

I've played with different gear ratios to get the best performance. With a 32" tall tire, 4.86 gears and shifting around 7400 rpm. I cross the finish line just after the shift light comes on. The engine is capable of shifting at a higher rpm but that would mean going to something like a 5.00 gear. I tried some 4.57 gears one weekend but the converter stall didn't like the gears and I run much slower. Put the 4.86 back in the the car picked right up again.

There's no exact formula to say what works since all vehicles are different. You run what you have and live with it or you experiment with different parts to get better performance.