Good times man. It's nice to see some sedans out at the track.

But I am a bit confused by the timeslip. I'm very close to that trap myself, but there's no way I could kit a low 13.2 with a high 1.9 sixty foot. If I can get a high 1.9, I'd be looking at a 13.5ish ET.

I guess the longer gears of the AT are helping here.

 

He's got a good bit more power than you, but the AWD and 5AT driveline drag is sucking out MPH on the far end of the track. I'd imagine a RWD 5AT would probably see an additional 2-3mph since it doesn't have the additional static and rotational weight of three additional axles, a transfer case, and an additional differential.

 

Sup Dave, when you going back to the track I want to see you hit 100mph in the 1/4 mile...

 

Winter's over - aint gonna happen...

 

I didn't intend to directly compare his and my cars. I've just noticed that the AT's can have lower ET's than the 6MT's for the same 60 and traps.

If you look at the top25 list on my350z, there's a guy named DayBlueZ that has run looow 13's at 103mph, but his 60 wasn't crazy. If you look at the 6MT's with similar traps and 60's, their ET's are a few tenths higher.

 

Trey... your posts are credible (IMO)... but are you referring to post that list text and no slips?... you know as well as I that the best way to judge your car’s performance is at the same track event on the same day or the same dyno event... I never have given ANY credit to text only… And there is no use in comparing different ET or dyno to different tracks and equipment…

If someone runs high 13s in a G35 at a particular track, I am much more impressed if I see that other G35s were running low 14s at the same track (same day)...

I don't have to tell you this - you know... So to figure out how someone got a certain ET and had a certain 60' is futile.

Numbers are bogus unless they are against similar modded cars on the same day at the same place – this has always been my take (for FWIW)

 

I understand, but that's when you're comparing cars or power. This list of top 25 times is a list of the top 25 ETs, period. No correction factor, or anything else. That basically means that if you're at a track like LACR, you're not getting on this list.

The guy that I am talking about specifically is DayBlueZ. His time is listed at a 13.170@103.19. His sixty is a 1.922. This is in an automatic z, on street tires. I know the guy; he's local, and he's cool as hell.

Compare that to another guy(Mojo Powered) that traps 103, and when he cut a 1.91 sixty, he hit a mid 13.3. That's a different of two tenths. That's in a 6MT.

The launches are close, within 3 thousandths of a second. The traps are close, within 13 hundredths of a mile an hour. Yet the ET's differ greatly. The cars are making similar power. The cars are getting out of the whole similarly. Larry(DayBlueZ) also has the 3.54 pumpkin. So the FD ratios are the same.

It just doesn't make sense to me. Having the 3.54 in the AT should make 3rd top out at somewhere around 93mph. He's trapping 103, so that means he's in 4th gear for a couple hundred feet, just like the 6MT. So both drivers are performing 3 shifts.

 

I only ever compare same day, same track, & same day, same dyno... I'm as analytical as you - My title in the field I'm in has included "analyst" as well... I fully understand your need and desire to make sense of the numbers... and to an extent it is a viable measure of performance... however it is not enough to ponder why one car does what another cannot...

The only real statistical analysis that is worthwhile is what happens on the same day at the same track or same dyno – measure-in specific variables and draw an educated hypothesis to what works and what doesn’t… That’s what I have done – it works for me.

 

But I'm not comparing absolute numbers or even corrections. When two cars pull 1.9 sixty foots, the conditions could be drastically different, but the numbers indicate that traction is comparable. Trap speed is the same way. If two guys trap 103mph in the same car, same gearing, similar power, but in wildly different conditions, it indicates the two cars at the times of the runs are making similar power. If two cars have similar sixty foots, and similar traps, the ET's should be very close as well. If they are not, then that either indicates really slow shifts, or differences in gearing.

 

Trey, i remember reading somewhere that the autos will actually have a little bit more torque than the MT. You might want to look into that. Even though the numbers are the same on infinitis website, the autos for some reason have more torque...not sure if thats correct, but i read it somewhere on the forum.

-Sean

 

2005 6MT Sedan

Mods:

UR underdrive crank pulley
Ported Crawford plenum
Ported throttlebody
Ported lower intake
Crawford hedders
Crawford high flow cats
Fujitsubo exhaust system
3.917 gear ratio
Rogue Engineering shifter
Z-tube
K&N filter
275/30-19 Kumho SPT tires
No spare
6 gallons high test 105 unleaded race fuel

I've run a best of 13.45 @105.2 mph (2.07 60ft time)

I have run quite a few 13.50-13.70's

 

I believe I justed Figured out why trap speed vary so much. I don't think trap speed alone is parallel to power. For example, In my other run, I had 13.3 with 105 trap speed. vs. my best ET Run 13.2 @102.

The difference of the two run, I had some wheel spin on the 13.3 run,
the wheel spin will increase MPH quite a bit even you are not moving forward much, but because you are not moving, you've lost some time. Therefore, the higher MPH at the end even the ET is lower. I was running at 32 psi & a little spin happens. I lowered it to 27 psi & got rid off the spin.

I think most non AWD cars lauch with some wheel spin, therefore will have
higher MPH at the end. My best ET run, I had absolutely no spin. I've seen those muscle cars running ~13.3 with 116 trap speed, spining like crazy off the line which generated a lot of mph but doesn't get them to thefinish line faster.

If two cars both have Zero spin off the line, then may be you could compare
the two in power vs. MPH. But in reality, spin varies car to car & run to run,
thats why ET is more important, more consistant & more useful. If I allow my car to spin more, for example, pull the AWD fuse & run in RWD mode with my 225 street tire, I am sure I will get much higher MPH with lower ET.

 

14.2
102mph
04 5at coupe K&N CAI, and motordyne 5/16 spacer
high humidity in san antonio tx.

 

That's an excellent trap for the car and mods. Congrats.

 

That certainly makes you the fastest all motor sedan, if not g35 period. Of course, that doesn't include ISMSOLUTIONS, but we never got a timeslip for his <12 runs.

Congrats. I know my car will never trap 105mph.