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StompNDump 11-03-2020 04:36 PM

SST Starting Point
 
2800lb car, 4.56 rear gear, 468 BBC 750 HP. Car runs 6.20 in 1/8 mile but not sure on 1/4 mile because its new. Back half ladder bar car14x32 rear tire.
They have a 10.90 class at a race coming up I wanna try and run in. Just looking for a starting point for my timers. I have a Dedenbear Linkage stop and Mega 450 delay box. Any help is appreciated. Possibly would want to shift on RPM also.

Robbie Welch 11-04-2020 07:32 AM

Re: SST Starting Point
 
Welcome to the class its a blast to run. The car you described sounds like a good fit in S/St. First off get your stop RPM to some where between 4200-4500 RPMs. Your throttle stop start timer .020-.030 once you find the correct start number(Don't change it) your finish TS number for a track with a DA around 1500-2500 Ft try 1.80 and adjust from there. I would think that should get you in the ball park. When you start running S/St if your pretty close to 10.90 (within a couple tenths) change your TS second number by 10 numbers at a time. If your way off make a 20 number change. Keep records of all changes and the weather its very important. Good luck and have fun.

StompNDump 11-04-2020 09:21 AM

Re: SST Starting Point
 
Thanks for your reply. I have heard a back and forth about shifting on time vs. RPM and also between a linkage stop and a baseplate stop. Whats your take on when and how to shift? Also am I at a disadvantage with a linkage stop?

Robbie Welch 11-05-2020 07:14 AM

Re: SST Starting Point
 
I'm old school and run a linking TS also (to be honest I'm limited on hood clearance) The majority of S/St racer run under carb stops. I think a lot of people shift on time especially the high HP cars. My car is middle of the road HP (runs 9.50 ish) off the stop) I've been shifting on RPM for 30 years it works for me and up until 2 years ago I ran a 3 speed trans. S/St is the most fun racing I've ever had. You just need to get use to the different pace of racing 1 or 2 time runs a day and going into eliminations with no time runs on race day. There's lots of ways to skin a cat. I hope this helps.

StompNDump 11-05-2020 09:01 AM

Re: SST Starting Point
 
Yes thanks for the help. I also am no high HP car. I would assume when shifting on RPM you stay in 1st while you are ON the STOP then just let car shift on its own at the desired RPM one OFF the STOP, correct?

Robbie Welch 11-06-2020 07:25 AM

Re: SST Starting Point
 
Yep that's how I do it. Leave the line go on the stop come off the stop and air shifter hits at 6800.Then the games begin. There's a lot of finish line strategies played out. When I was running the 3 speed trans the TS and the 2nd gear shift where every close to one another. That's not and idea situation

Lenny5160 11-06-2020 02:04 PM

Re: SST Starting Point
 
You'll have more MPH if you shift on RPM after you come off the stop. That's how I'd do it if I were you.

I'd probably stay wide open a bit longer, turning the stop on around 0.300 to get the car moving and allow you to be coasting on the stop through the 60' timer. I use 0.500 with my car that runs right at 6.40 in the 1/8 mile wide open.

Keith 944 11-06-2020 09:42 PM

Re: SST Starting Point
 
You have some good advice from some really good racers, take their advice.
My 2 cents, use it and test,test,test. every car-combo is different. it will show you what it likes. more important than mph or anything else is repeatability. there is a sweet spot for cruise rpm don't go too low....

J518 11-06-2020 10:37 PM

Re: SST Starting Point
 
You have a really close setup to mine. I'm 2815lbs, 4.88 rear, and closer to 700-725hp. At 1800DA in the 1/8th I ran 6.25.
So shift wise don't waste your time on shifting into high while on the stop. 2800lbs is still alot of weight and you are not going to break the tires loose in low.
I come on the stop at .375 and at topeka with 2100ft DA I had 1.95 in the stop and ran a 10.906. With that hp I think you should aim for higher dead stall rpm. I would shoot for 4600-4800rpm while on the stop.
Best of luck! Never understood why we like more complicated racing haha

StompNDump 12-03-2020 09:19 AM

Re: SST Starting Point
 
Just wanted to say thanks to everyone for the info. I managed to go some rounds but had luck on my side also. Struggled with getting 60fts to repeat and 330. 2 passes would be close then the next would be a pick up or slow down in 60 ft or 330's. Im thinking the carb may not like the throttle stop, in the morning cool air there was a slight hesitation when coming off the stop, this later cleared out as the weather warmed up. Time to start testing more.


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