Drag Strip tips and advice needed.

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Kent mosby

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I took my 73 scamp to the drag strip a few weeks ago. It has a 512 RB with Super sniper EFI. I mistakenly did not have the Closed loop and learning on at all before I took it there and during the races and my times were underwhelming. 13.4 at 104 best. I subsequently had a tune done remotely by Richard Nedbal and have driven the car a bit since. I have a 727 with TF2 kit and Quicksilver shifter, no line lock hooked up or transbrake. Rearend is 8 3/4 with 3.91 gears. Mickey thompson Street ss radials. 3000 rpm stall TC.

During the first 3 times down the track, the tires did not slip at all. I did not burnout as it was my first time drag racing. I also did not manually shift the car but let the transmission do the shifting. I did rev to about 2000-2500 before releasing the brake on launch. My best 60 ft was 1.97 or so.

What tips, techniques or advice should I do for the next test and tune coming up tomorrow?
Youtube has many videos on how to launch but launching a 300 hp car is different that 500 and tires make a difference. Knowing my setup, specific advice for me would be appreciated.
 
I was hoping that I could get some help as I am a newbie to racing. I have built what I think is a good car but I do not know how to get the most out of it. Certainly the weak link to this car's performance will be my ability. Any help would be appreciated. Please offer whatever wisdom you can.
Thanks in advance.
 
Keeping it brief: Lower those radials to about 16 psi, leave off idle, converter should flash to 3000+/- hopefully. Manual shift at a higher rpm. What was the rpm through the traps? That’s just some initial ideas without knowing much. There’s a lot of info people will want to know so be ready:)
 
Sure your getting full throttle? 1.97 60ft seems very slow for that combo should be in at least 1.60s?

I'm at 1.80s and i only have a small cammed 413 in my duster.

You should manual shift it and try 5,000 rpm and keep stepping up the shift rpm as it gets faster.

And another thing lol do not stay in first if you do a burnout shift to 2nd as soon as the tires are spinning.
 
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Thanks, After I had it tuned by Richard, I am sure about the throttle being wide open. Prior to that, the tune for the EFI was way off. I expect better tomorrow. I did not burnout but I am aware of getting into 2nd asap so that I don't trash the trans. I have manual shifted at 5700 on the back roads and that seemed much better. Richard set the rev limiter at 6500 and says that this car should be safe there. I am not sure about trap rpms as the only tach I have is on the EFI readout 3 inch display.

Can someone explain "leaving off throttle"? My neighbor, A hot rodder, says to get the rpms up before launch. I am very new and willing to learn.
 
with "preloading" the suspension / trying to leave at higher rpm you kind of reduce the suspensions ability to react to the launch.....i always leave from idle and i think it´s better. At least i do not have any stress at the starting line.

Regarding the trap rpms: with the sniper you could do a datalog and watch the run later on the computer screen. You can determine converter stall and trap rpms, ignition timing, TPS and much more.

Take it easy, A-body with such a big motor could be pretty fast. You´ll get there with some seat time.

Michael
 
Another thing you need to learn early on Sir !! Only make one change at a time !! I don’t care what anyone says !! Make one change at a time. That way you will know if the change you made makes you faster or slower ! Or fixed your concern or didnt fix your concern !! Be consistent with your starting line procedures ! What ever you do before pre-staging do it the same every time ! Try to stage your car the Same distance in beams every time !! Take the same amount of time every time you pull up on the track !! All these things I’ve said will affect what the car runs on any given pass !! If your consistent with everything you do ! The car will be as consistent as you have built the car to be !! Make sure you are straight in your lane when you stage every time !! If your run down the lane your in is shaped like an S your ET will reflect a slower time !! If your running 1/8 mile you want to run 660 feet!! Not 680 feet or more !! If your running 1/4 mile 1320 feet you want to 1320 feet not something more !! So line the car up straight !! Go straight down your lane ! If you have to steer your car a lot during a run !! That’s probably your red flag that your suspension is not setup right !! Sir there are literally hundreds of things to know and learn ! You will not learn overnight ! I’m 54 and have raced since I was 15 yrs old !! I have bracket raced for all of those yrs... it’s fun ! I love it ! And I love it when some one like you want to learn the sport !!

thank you Sir
Rodney
 
can you give us a your engine specs makes a difference on launch technique car should easily be 2 seconds quicker
 
What profile are the rear tires? For what its worth, I run Hoosier drag radials (275/60/r15) and they like 18-19 psi.... 1.42 60' times with my small block. If you have a lower profile tire I would go a little higher (20-22psi).
 
I am running 255/60-15 MT ss streets. They were at 20psi. no slipping. The engine was built by me with a 440 source rotating assembly, lightweight forged crank etc. Cam is
244/252 @ .050”, 282/290 adv, .516”/.537” lift(1.5:1 rocker), 112 sep, .016”/.018” lash from Oregon cams. Trickflow 240 heads, torker 2 intake, TTI 2 " headers into PYPES 3" into 2.5" after the Race pro mufflers. Hughes 3000 stall TC. Super sniper EFI, Hyperspark ignition and distributor. All the components I thought would make a pretty fast car. I am probably the weak link. Here is the best time slip.
time (1).jpg
. Car 634. Thanks for all the help.
 
Where have all the gurus gone?! This guy needs some pointers, has the cat got your thumb??
 
Kent mosby said:
I am running 255/60-15 MT ss streets. They were at 20psi. no slipping. The engine was built by me with a 440 source rotating assembly, lightweight forged crank etc. Cam is
244/252 @ .050”, 282/290 adv, .516”/.537” lift(1.5:1 rocker), 112 sep, .016”/.018” lash from Oregon cams. Trickflow 240 heads, torker 2 intake, TTI 2 " headers into PYPES 3" into 2.5" after the Race pro mufflers. Hughes 3000 stall TC. Super sniper EFI, Hyperspark ignition and distributor. All the components I thought would make a pretty fast car. I am probably the weak link. Here is the best time slip.View attachment 1715566619. Car 634. Thanks for all the help.
Click to expand...
You certainly got a potent set up there, your launch is the least of your problems. You could probably use a better stall converter but for now I wouldn’t worry about any of that . I’d say you’re down at least 10 mph minimum and 1 1/2 seconds on et For starters. Definitely would need to know where the cam was installed your initial and total timing fuel delivery questions etc.
 
12many said:
Where have all the gurus gone?! This guy needs some pointers, has the cat got your thumb??
Click to expand...

I'm only saying there's too many things wrong with this car..
Trying to be respectful.
Its hard enough doing an autopsy over the phone.. this could easily go 20+ pages...
FlyFish pretty much said it.. sb going 1.42 60 foot
 
Yeah go back with a good tune because you're about 100hp off or more! Lol you should be trapping about 15mph higher.
 
'63GT said:
I'm only saying there's too many things wrong with this car..
Trying to be respectful.
Its hard enough doing an autopsy over the phone.. this could easily go 20+ pages...
FlyFish pretty much said it.. sb going 1.42 60 foot
Click to expand...
Wasn’t directing at anyone in particular, just that the usual suspects haven’t weighed in which is a little odd:)
 
12many said:
Wasn’t directing at anyone in particular, just that the usual suspects haven’t weighed in which is a little odd:)
Click to expand...

No worries.. maybe there's someone local willing to help, one on one.
Poor guy is upside down...
 
Kent mosby said:
I took my 73 scamp to the drag strip a few weeks ago. It has a 512 RB with Super sniper EFI. I mistakenly did not have the Closed loop and learning on at all before I took it there and during the races and my times were underwhelming. 13.4 at 104 best. I subsequently had a tune done remotely by Richard Nedbal and have driven the car a bit since. I have a 727 with TF2 kit and Quicksilver shifter, no line lock hooked up or transbrake. Rearend is 8 3/4 with 3.91 gears. Mickey thompson Street ss radials. 3000 rpm stall TC.

During the first 3 times down the track, the tires did not slip at all. I did not burnout as it was my first time drag racing. I also did not manually shift the car but let the transmission do the shifting. I did rev to about 2000-2500 before releasing the brake on launch. My best 60 ft was 1.97 or so.

What tips, techniques or advice should I do for the next test and tune coming up tomorrow?
Youtube has many videos on how to launch but launching a 300 hp car is different that 500 and tires make a difference. Knowing my setup, specific advice for me would be appreciated.
Click to expand...

Is that track Boise by any chance??
If so, that track correction factor is 2900' (though controversial) could be 5 tenths there..
 
I hope that the new efi tune will help. I know that it should be faster. As for local help. I have an extensive dyno tune at EPC racing in Spokane in August 7th or 8th or so. I have been waiting 2 months for that. As to the new tune I had. Richard Nedbal is an expert in efi. If it is not right now, I don’t know what else to do but wait for the dyno tune. EPC racing are the only Holley tuners within 300 miles of me.
 
The track is 8 hours from Boise. Elevation 2200-2300 or so
 
512cid, and 3.91 gear......something is off.
fuel is in question but it you were loosing or running out of fuel. your 60' would be good and then slow down. it is all slow (to me)
what is the carb
timeing????

EDIT: fuel injection.:BangHead::D
 
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Spokane county raceway. Not sure what you are referring to with 512 and 3.91 gears. I have 6an line into the efi with an in tank pump.
 
Kent mosby said:
I took my 73 scamp to the drag strip a few weeks ago. It has a 512 RB with Super sniper EFI. I mistakenly did not have the Closed loop and learning on at all before I took it there and during the races and my times were underwhelming. 13.4 at 104 best. I subsequently had a tune done remotely by Richard Nedbal and have driven the car a bit since. I have a 727 with TF2 kit and Quicksilver shifter, no line lock hooked up or transbrake. Rearend is 8 3/4 with 3.91 gears. Mickey thompson Street ss radials. 3000 rpm stall TC.
Click to expand...
Expand ^^^^^^
 
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I'm no help with EFI (I'm a carb guy), but I would agree with others that you appear to be down on power. Your MPH at the 1/8 and 1/4 mile show that...which if you plugged it into a HP calculator you might loose your lunch. Even though you have a small cam, it should be doing better than that. Try it again after the tune and let us know. By the way, when it does get running right you should have a traction issue with those tires, unless your chassis is well sorted. Best of luck.

Edit:
Kent mosby said:
..............................What tips, techniques or advice should I do for the next test and tune coming up tomorrow?
Youtube has many videos on how to launch but launching a 300 hp car is different that 500 and tires make a difference. Knowing my setup, specific advice for me would be appreciated.
Click to expand...
Unfortunately, you are probably making about 300hp.
 
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