200-series at the dragstrip (1 Viewer)

[linuxgod]

Wow, I shoulda listened to @CharlieS

Last run, got her going pretty good, making the 2-3 shift, when suddenly BANG something in the tranny let go. Total loss of power, engine hits the limiter. Then the engine started knocking REALLY bad. Oh man... big cloud of blue smoke. I think at this point the driveshaft fell off the back of the transfer, cause it pogo'd the truck over, I think I rolled 3 times. Geez those airbags make a loud noise when they go off.... phone got tossed out and crushed, so no photos, sorry.




Actually none of that happened. Truck is totally fine, just a thin layer of oil and schmoo all over the tailgate that the tires kicked up.

First run, TRAC off, PWR on, trans in D, I rev'd up to about 2000 rpm, standing on the brakes, then let her rip at the green, never lifted. I'm #962.

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Second run, same settings, except this time I started in S2 and manually shifted. I wasn't very smooth at it, shifted kinda early.

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Third run, same thing, but I was better at shifting. I really didn't like how it reacted, it was taking too long to shift. Maybe it knew better than I did? Anyway, not as good.

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This truck is a pig, that's all there is to it. Too much weight. I gassed up on Sunday night, and stupidly forgot about tonight and filled the tank with 87 regular. More weight.

But we had a BLAST. Lots of cars, all types, even some drag bikes. I know there's video, but I don't have it yet. Will post if I can.

Early shift might've helped you. Here's the HP/torque curve for a 2008 LX. From https://www.automobile-catalog.com/curve/2008/1429145/lexus_lx_570.html:

Sorry wish I'd found this sooner for you. Basically you just want to shift to the next gear when the next gear would make more HP than the gear you're currently in. If you trust the above graph then you always want to hit redline. But if the above isn't the real output of your motor, you could be better off shifting early if the RPMs for the next gear will put out more HP than you're getting in the current gear. (OTOH if the above is real you always want to hit redline since even the 3->4 shift would go from 5800 RPMs to ~4300 RPMs and the above clearly shows you're making more HP at the top end than at 4300.

That said I think the above is measured at the flywheel, not at the wheels, so if the HP curve at the wheels does not match the flywheel curve then the shift points change. Note that I don't actually care how much HP you are really making, I only care that the curve of the graph matches the RPM points. Also obviously I have no idea if the above is accurate.

 

[JohnJB]

The faster ET of the best timeslip is largely accounted for in the 60' time. Whatever happened at the starting line to get you through the first 60 feet at about a tenth faster most likely accounts for reduction of the overall elapsed time. The old rule of thumb is that a tenth in the first 60 is worth 2 tenths in the overall 1/4, but I suspect weight and aero of a 200 series messes with that formula a bit. I will saying growing up racing 4,5k lb trucks that were marginally faster, it held pretty accurate.

 

[KLF]

So what did your son buy for dinner ? Which pass was the slow mobile ?

He wasn't able to run the bike, so we called it off. We're gonna go back on 7/21, I'm gonna take the Miata this time just for fun. He's gonna bring the Geo Metro and we'll compare my slips from this week, best time gets a free dinner.

I think the weight had a huge effect, but I swear I could feel when the poor aerodynamics were holding it back. It's like it hit a wall at about 80 and the acceleration plummeted. It was still pulling, but working harder.

The slowest one in the other lane on run #1 was a co-worker in a Subaru Outback wagon (family car). We laughed our butts off in the pits when we got back in, it was so fun.

Run #3 I was next to a beater Civic on a bottle. He had a terrible reaction time (R/T), so I was way ahead of him for the beginning, then he blew past me.