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-   -   Tell me a few things about this pass.. (https://www.rx7club.com/time-slips-dyno-121/tell-me-few-things-about-pass-344344/)

sk8world 09-01-04 05:25 PM

Tell me a few things about this pass..
 
I have not been doing the drag racing thing for over a year and just wanted to know what times I can expect with a good pass (better 60 foot time) and will my MPH change do to the 60 foot time.
Made 3 passes this weekend on an 1/8th mile track. Needless to say I was having a very hard time with coming out of the hole.... Here they are

60 foot 2.3 2.3 2.6
et 8.5 8.3 8.6
mph 93.? 93.? 94.?

I ran a little more boost each time... Before (last year on old setup) I was able to go 1.80 60 foot with a 7.80 et at 90 mph.

I guess my question is if I was to cut a 1.7-1.8 60 foot will my mph go up? Just wondering if I will be able to hit the mid 11's or lower in the 1/4.... Thanks...

SPOautos 09-01-04 05:56 PM

Actually, if you cut a lower 60 foot your mph normally drops a little. It looks like if your 60 was the same as it was in the past youd get about the same numbers as you did in the past.

Stephen

sk8world 09-01-04 07:13 PM

Thats funny because my highest mph before was done on one of my best 60 foot times.. (1.89 at 7.90 @ 90.0mph in 1/8th)

Based on the other 1/4 mile times I have compared mine to.
Compared to some of my older runs with the same 60 foot the mph was 4-5mph slower before. Oh well we will see once I get some good rubber on... I am confident I will see mid to low 7's. But you run what you run, right!!

SPOautos 09-02-04 02:25 PM

That could be attributed to different tires if you are comparing runs with ET streets versus without ET streets. Running ET streets usually drops your mph a little....maybe not much in the 1/8 though, I think its mostly the last part of the 1/4 where you really see the difference in tire profile start to take effect.

Also, shifting can make quite a difference.

If you look at your info in your first post your fastest mph was also your slowest ET. Typically that is the case, as your ET drops so does your mph. But things like shifting and tire profile can mph as well.

But ya, your right....no point in us guessing when you have some ET streets in your garage haha

I hope it does well,
STEPHEN

sk8world 09-02-04 06:20 PM

Oh, Also I found a run from last year that was the same et and same 60 foot but this time I was 5-6 mph faster this time. I guess that is what was getting me.. I will let you know what I make next time.. By the way what was your 1/8th mile speed.....?

SPOautos 09-03-04 09:05 PM

99mph

Also, tire size will make a difference in your mph so if your comparing runs with ET streets against runs with street tires then they prob wont compare right. The ET streets have a different profile and effectivly change your gearing, especcially as you get going down the track cause they will "grow" taller the faster you go

STEPHEN

sk8world 09-05-04 11:15 PM

well, again I tried to get a better time but could not put it all together. The track was so packed I only got to make 2 runs. First was another 2.4 60 foot. I did not drop the clutch again but slipped it a little out through all of 1st gear. Second run I just dropped the clutch and the car hooked very well until the top of 1st and then it smoked the tires bad and had to shift which caused me to bog in 2nd then I missed 3rd and just coasted. Still trapped 8.2 at "76mph" (1.90 in the 60 ). Man, I guess I am getting old and forgot how to drive but I really feel 7.60's are capable. Going back out next wednesday.

MichaelFregoe 09-06-04 12:24 PM

I would never condone reckless driving on a public road.. But I have practiced launching in a parking lot before.. Launch go 60 foot and stop.. Do it again.. Just make sure you are secluded and no one cares about the noise. Best of luck.

sk8world 09-06-04 01:12 PM

Thanks, But it was just me trying to launch my old way. I used to try and slip it all through 1st to keep from getting wheel hop. Once I went to et streets I did not have to worry about that any more. I only made a hand full of passes on the et's before I sold them. Thought I was done with drag racing.... I just have to drop the clutch around 6k...

SPOautos 09-07-04 11:03 AM

Yea, I was just fixing to say now that you have that single your going to need high rpm launching. You cant launch it like you use to do the twins. Watch out for your diff man, it dosnt like 6K+ rpm clutch dumps. Thats why I dont track my car hardcore, to get real good 60's with non seq or single you need 6K+ rpm dumps and it'll kill the diff in a heartbeat. Especially with street tires/drag radials, with ET streets they help out with the initial shock but they are hard on axles so you cant win for loosing lol.

Stephen

radkins 09-12-04 06:54 PM

Stephen,

Can you explain why MPH drops with better ET's? I have noticed this on my runs, but can seem to find a logical explanation for this. It seems like if you get going faster earlier then you would have a faster MPH.

Ryan

Snook 09-13-04 12:02 PM

yeah that always confused me too
although my traps kept going up last time each run as I got a better 60 time
but I think the engine was just working better because it was warmed up??

i noticed the supras trapped better the more they ran the car too

sk8world 09-13-04 06:12 PM

Stephen,, I just remembered when you ran your best 1/4 mile time you said you only trap 12.3 @ 125 (I think) due to bad 60 foot time.. You think you will even trap 120 then?

Snook 09-26-04 01:25 AM

If you need tips on launching lmk. I've figured it out after experiencing the worse wheel hop of anyone on this board up to 65mph and 2.0-2.2 times I cut a 1.8 on my last run at the track when I was booted lol

its true what that member from japan on here said
if you get wheel hop launch at higher rpms and drop the clutch haha...seriously I was in shock my head pinned to the headrest it felt orgasmic

sk8world 09-26-04 11:31 PM

Here is my run from today...

1.911 60 foot
7.76 1/8th
96.26 mph

Still could not get my Drag radials to hook but at least I was able to get some better times than before....

Stephen, I got my best time with the best mph I have ever had!?

sk8world 09-27-04 07:43 PM

Here is my slip..
 
1 Attachment(s)
Just thought I would post it...

sk8world 09-27-04 07:56 PM

Mine is lane 2 with the 7.7. Yeah, I lost but look at the 60 foot time... I was walking him down....

Snook 09-29-04 02:34 AM

1/8 mile is for pussies

sk8world 09-29-04 09:15 AM

1/4
 
I do not know about being for pussies as there are a bunch of big ass mean rednecks out there at our local 1/8th track that would disagree with you.... (not me) I think they only built the 1.8th track as thats as long as the cotton field was!!! Just messin around!!!

Really, I would prefer a 1/4 track but we do not have one...

Gargamel 09-29-04 06:02 PM

So, what did you do different to gain more mph?

sk8world 09-29-04 06:29 PM

I finally got my GT40R kit installed.. Still running my stock motor (for now).

ZoomZoom 09-29-04 07:29 PM


Originally Posted by sk8world
I finally got my GT40R kit installed.. Still running my stock motor (for now).


Do you have any HP dyno sheets? I was going to buy this turbo but decided to get the R85

sk8world 10-01-04 05:05 PM

Zoom, Remember me... I bought your PFC and was going to buy your 35/40?? Yeah, I have some sheets but not too impresive... It was at 13.5 psi and my air fuel was all over... I am making some changes and the car feels much better so I will put it on the dyno next week and post the results.. I expect 380-400 area at 17psi. Not much better than you did on your 35/40 kit... But remember this turbo is made for boost above 20psi!!

sk8world 10-05-04 12:34 AM

1/8th
 
Got to use what you got... I would it if we had a 1/4 track here but lets face it, once you get to the end of the 1/8th you have one more shift to make and thats it for the 1/4. you can usually tell what you will run in the 1/4 by your 1/8th mile trap speed and et...

SPOautos 10-05-04 02:48 PM


Originally Posted by sk8world
Got to use what you got... I would it if we had a 1/4 track here but lets face it, once you get to the end of the 1/8th you have one more shift to make and thats it for the 1/4. you can usually tell what you will run in the 1/4 by your 1/8th mile trap speed and et...

Exactly....everything important happens in the first 1/8 anyway


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