baddogz28

iTrader: (6)

I'll try to make my explaination as easy to decipher as possible, here goes:

The first time I ran my car, I ran 13.6 @ 106. 60's in the low 2.1's.
(Rt. 66 Raceway, Joliet, IL)
Mods:
K&N Filter

Tires:
Kumho Ecsta Supra 245/16

Last time I ran my car, I ran a best of 12.844 @ 111.50. 2.132 60'. (Rt. 66)

Mods:
K&N
SLP ram air box
Whisper Lid
Lingenfelter intake
Smooth Bellows
GMS MAF
SLP Loudmouth

Tires: Same bald Kumhos...

Today I ran a best of 13.1 @ 106 (1.9 60') at US41 Dragway (Morocco, IN) and failed to break into the 12's. The altitude is 662' above sea level, the temp was between 75 and 80 degrees, and the track was a little slick around the 1/8th mile. I was bogging bad off the line after 8 second burnouts, regardless of how I tried to launch... I varied from slipping the clutch at 3000, to dumping the clutch at 4000. The car consistently trapped 105-106 all day long. Needless to say, I wasn't pleased. Guys with very close to my mods with autos (Matt-mdblackZ28, Mike-NBM2001Z28) were running consistent 12.2's at 110.

Current Mods in sig...

Tires: 275/40/17 Nitto 555r drag

Notable ****:

I am on my stock tune. The SES light is on because I deleted EGR and my AC unit, along with the AIR. My clutch is getting weaker, but isn't slipping yet, and my posi is starting to fail (had a one tire fire in 2nd gear in the burnout box. ) Starting to get some phantom noises out of the hatchback too, sounds like a hollow rattle when I am off of the throttle that goes away when I am on the gas- possibly my 10 bolt getting ready to punch out?

Obviously, my drivetrain situation isn't helping things, but I think there is more to it than that. Knock retard? Closed loop operation of the PCM?

Oh, and it seems to fall on its face up high.

Cliffs notes:

I have all the boltons AND drag radials and I was quicker and faster when I was basically a lid/catback/SLP ram air car.


ANY HELP GREATLY APPRECIATED!!!

glennster

iTrader: (1)

Too many variables.You need to do a 3rd gear WOT with a scanner and log/movie whats going on.I found my car would fall over at 5300 on the dyno/track.I found the A/F ratio was near 11 to 1,tuned it and picked up over 40+HP.Its a different car now,can't wait for the track next week.

tuff

iTrader: (15)

Dud i thought you had it tuned.You know with your mods your afr is wacked and that is why your running that way.Don't get pissed first time out thinking your going to set the world on fire **** happens been there done that.You just need to get it tuned.

JNorris

iTrader: (4)

What were the weather conditions when you ran the 12.84?

John

baddogz28

iTrader: (6)

J, it was nice and cool out...

Mike, the car put down nice numbers on the dyno, so why so weak at the track?

NBM2001z28

iTrader: (43)

i have less then baddog right nowm, and he's right, i hit 12.2 all day. 9 times in a row. I really should've bracket raced the damn thing and took everyones money today. I have headers, converter, gear, 28" tall tire and a air lid and im running way faster then him. When the car was a 6 speed with a stock gear and a 245 nitto i was running 12.0 @ 117, That's untuned and it still is. i have a evap service engine soon code right now btw...

xttc2000

how many times did you run close to 12.844 @ 111.50. 2.132 60'. (Rt. 66) ?
i would most likely say that was a fluke run.
Your mods at the time: 5hp lossed overpriced intake and loudmouth?
seems highly unlikely for consistant 111.5mph traps.
i would hope your headers really screwed with your A/f ratio.
did you notice a SOTP power loss after the headers? if you were able to beat my brothers GTP on the highway before you got your headers that should have netted you 112+ mph trap times, he walks all over cars significantly faster than your track times on the highway daily.

other than that was your clutch slipping up top?
and you probobly added 40+ pounds of rotating to each axle with your 17s, 80 pounds of rotation mass acts like ~800 pound to your car. theres at least .5-.8 in ET.

SilverGhost

iTrader: (53)

hmmm.

if clutch is slipping decently on the big end you wouldn't notice it but it would cost you MPH for sure. are you grabbing 4th or trying to finish in 3rd? if its slipping some when you shift you might not notice that either but that would slow you down a good bit.

you need to find out what codes are being thrown, who knows what's going on in there. i agree, rather odd you picked up a pile of HP on the dyno from those headers and are not seeing gains at the track.

as mentioned, those much heavier wheels aren't helping anything, will be another small contributer to loss of MPH with the heavier mass and rolling resistance over the stock rims.

i wonder what the DA was like when you went 12's vs this time. i hear the air was actually pretty shitty today.

BlkZ28LS6

iTrader: (1)

I was also at 41 today and ran after baddogz28 left. I also have an M6 with similar mods, and also ran better times with just a lid and catback compared to today's times with LT's, FTRA I have now. I put down 337 hp and 346 tq on the dyno back in February with my mods in sig. A year ago I ran a best of 13.321 @ 106 (2.1 60') w/ just lid and catback. Today I only ran 2 times...
Run 1: 13.751 @ 105.37 (2.300 60') 30 PSI in rear tires
Run 2: 13.432 @ 107.10 (2.250 60') 18 PSI in rear tires
P.S.
No SES codes.
The car was at stock weight a year ago and today.
Tires are BFG Comp.s (Not Drag Radial)
The track was VERY slippery all over. (Wheel hopped all over the place too)
I don't want to hijack your thread BaddogZ28, but I was having the same problems as well. I think it was just a bad day for a lot of us.

WOT

iTrader: (1)

just a note here... most go by the 1.5 to 1.6 ratio. 80 pounds would be around 120. That is if it was a true 80 lbs.

xttc2000

ok then i stand corrected, for some reason i had it burned into my mind that a pound of rotating mass is like 10 on the car, lol.

off the line you were bogging? no spin but bogging?
should have tried the old 5000 rpm shatter your 10 bolt launch
if you catch 3rd out of redline at 2nd with a hardcore high rpm clutch dump do the rpms keep up with the speed of the car or do they rev up and then settle? or put it in 6th on the highway at a low speed/rpm and floor it, watch the RPMS. either of those methods will give you a pretty good indication of clutch slippage.
and chris if you need the car scanned you can swing by any time.

dug

iTrader: (10)

Sounds like the clutch is slipping. When my clutch started slipping it cost me 3mph. It didnt feel like it was slipping much but it made a noticable difference in quarter mile times and mph.

john_matrix

The only good thing that came of yesterday was me getting a suntan...

That was definitely an interesting track. Way different than RT 66.

baddogz28

iTrader: (6)

Scanning this week.... Hopefully the problem is that easy to find.

baddogz28

iTrader: (6)

And I walked away from him. Go figure.
As far as thinking that it was a fluke 12.8, I would think that beating your bro would substantiate the capability of that setup.

I originally thought that maybe I did lose a little SOTP (or not have gained too much), but determined that maybe that was because I was keeping off the throttle BC the car is so damn loud. And the dyno results with Jucin were good, so I guess I just figured that I'd be OK at the track...

And I wasn't consistantly 111.5 traps, more like that was my best but I was consistantly 110.

baddogz28

iTrader: (6)

Yeah, obviously I have driven cars with slipping clutches before, and it wasn't very pronounced if it was happening at all.

Right? WTF? Hopefully the problem jumps out at us when we scan the car.

They sure didn't seem that much heavier than the snowflake crap that I had on the car... But yeah, the rolling resistance is greater.

It was pretty bad, but it didn't stop Matt and Mike from running pretty good.

baddogz28

iTrader: (6)

That's wierd, I don't know what was up with our cars, I would think your car should be low 12's too.

baddogz28

iTrader: (6)

Bump for other input... Talked to service manager at my dealership, he says I'm probably running pig rich.

glennster

iTrader: (1)

I went from 16" stock wheels to 17" SS wheels and lost over a consistant tenth.When you scan it watch the 02's,mine were damn near .980.You can do some searches on LFT's and what to watch for,the more info you have the quicker you will see the problem.Then again,some days at the track don't come out like we want and going home looking at time slips,we wonder whats going on,then next week we throw down a new best and can't figure it out.

gnxs

Chris,

We were running at Byron the same day and everybody was running at least 2-3 mph off, myself included. One of the guys plugged some numbers in a DA calculator and came up with a figure of more than 2,600 DA. There was also a very strong headwind. I think both the DA and the wind were factors in our runs at Byron. I don't know about wind conditions at 41, but perhaps the relatively high DA (for this area at least) was part of the issue.

Do the guys who were trapping 110 normally trap that mph or were they off also?

Forgetting the DR/one-wheel burnout issues, your trap speed is certainly not right for your mods. It sounds like there are some issues with your car (besides the so-so conditions on Sunday).

EDIT: I just noticed someone mentioned you now have 17 inch wheels on. I lost 2 tenths after replacing my 16 inch rims/tires with 17in Speedlines in my LT1.