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-   -   estimate my trap speed in 1/4. (https://www.rx7club.com/time-slips-dyno-121/estimate-my-trap-speed-1-4-a-467221/)

TwinTurbo_SE7EN 09-27-05 04:26 PM

estimate my trap speed in 1/4.
 
I raced a 2002 Z06 with heads/cam/all bolt-ons that trapped 123 mph in the 1/4. we went from 40 mph to ~140. I was ~ 1.5-2 cars back when we let out. How fast do you think my car will trap in the 1/4?

Thanks.

neit_jnf 09-27-05 07:14 PM

sounds like a school problem hahahaha

A VERY ROUGH ESTIMATE:

if our cars are 12 ft long and you were 2 behind it means you were 24 ft behind

so in 100mph difference (140-40) you lost 24 ft

100mph = 147 ft/s 140mph = 205 ft/s

205-147 = 58 ft/s

my brain hurts... I need either the total distance travelled or the time it took you or both to complete the calculations hehe

but by the time you were going 140 he was already past 140... i give up

you'll trap 115, there it was way faster that way hahah

r0gu3 09-28-05 08:16 PM

Two car lengths makes 8 mph difference?

neit_jnf 09-29-05 07:22 AM


Originally Posted by r0gu3
Two car lengths makes 8 mph difference?

I don't know I just said 115 because I didn't want to keep on calculating :D

but if by 140 they're *only* 2 car lenghts apart I would guess they're not too far in the 1/4 mile

2FAST7S 09-29-05 10:46 AM

Can you drive? lol
Have you had your car dyno'ed??? Generally if you make 300 youre trapping around 110, 350 is about 115...
go to the drag strip and find out! As it is we're just guessing.

TwinTurbo_SE7EN 10-06-05 10:25 PM

353 rwhp. and I am a decent driver. I trapped 108 with 251 rwhp or less since the 251 was on a base pull at 14 psi and my previous 108 MPH trap was at 10 psi.

neit_jnf 10-07-05 07:45 AM

something just doesn't make sense... if you dynoed 251whp at 14 psi there's something wrong with your car

now 251whp at 10 psi is believable but at that power level the car won't trap 108

I was trapping 107-108mph at 315whp at 13.5 psi now I'm trapping 110mph with a metal core high flow cat at the same boost. I wonder what my power is, I'm guessing 320-325whp

TwinTurbo_SE7EN 10-07-05 10:40 AM

started out at 251 rwhp on the dyno (A/F in the high 8s)...finished tuning with 353 rwhp at 14 psi (A/F in the low 10s). boost was set to 14 psi that morning. so Im assuming that the power it made would be less at 10 psi for the run at the track with a 108 trap speed, boost was at 10 psi and Im assuming it couldnt have been making more than 250 at the time.

matty 10-10-05 10:14 AM


Originally Posted by 2FAST7S
Can you drive? lol
Have you had your car dyno'ed??? Generally if you make 300 youre trapping around 110, 350 is about 115...
go to the drag strip and find out! As it is we're just guessing.

exactly.

Outkast 12-13-05 08:06 PM

I trap 114 on 330 rwhp and 124 on 410 rwhp

ForceFed 01-04-06 05:04 PM


Originally Posted by neit_jnf

now 251whp at 10 psi is believable but at that power level the car won't trap 108

I was trapping 107-108mph at 315whp at 13.5 psi now I'm trapping 110mph with a metal core high flow cat at the same boost. I wonder what my power is, I'm guessing 320-325whp

You can't possibly be serious? Either that or you could just be the world's worst driver :)
My stock FD trapped 84mph in the 1/8th mi and 107 in the 1/4mi and all I had was silicone vac hoses, RB springs and Tokico 5-ways, LOL! Try practicing your 1-2 and 2-3 shifts and you will be amazed at how much speed you'll pick up in the 1320. :)

neit_jnf 01-04-06 06:02 PM

I consistently trap 109~110 pass after pass with et's between 12.8 and 13.1 on street tires and kinda worn clutch (original with 45k miles)

I'm not the best driver but at least it's consistent...

maybe better tires and a new clutch is what I need?

matty 01-05-06 07:18 AM


Originally Posted by ForceFed
You can't possibly be serious? Either that or you could just be the world's worst driver :)
My stock FD trapped 84mph in the 1/8th mi and 107 in the 1/4mi and all I had was silicone vac hoses, RB springs and Tokico 5-ways, LOL! Try practicing your 1-2 and 2-3 shifts and you will be amazed at how much speed you'll pick up in the 1320. :)

i think your stock trap speed is high. i dont think its that it really represents what stock fd's can do. From what i have read it seems that most cars trap 100mph plus or minus a few.

ForceFed 01-05-06 07:09 PM


Originally Posted by matty
i think your stock trap speed is high. i dont think its that it really represents what stock fd's can do. From what i have read it seems that most cars trap 100mph plus or minus a few.

I won't dispute that. The problem is that most stock FDs aren't running nearly as healthy as they should and unfortunately most owners don't have anything to compare them to. I didn't either. I thought my FD was a factory freak when it ran 13.5s@104-105 when I still lived in upstate NY. Then I got down here to Charlotte, raced an all motor Maxima from a roll and lost. Then I noticed it wasn't making full boost on the secondary in 2nd gear. So I replaced the vac hoses with silicon ones and apparently got all my lost power back and the difference in power was shocking. A stock FD running 100% has the potential to be a very quick car considering its age.


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