cabech984

iTrader: (11)

I just took my Firebird to the track for the 1st time since installing a big batch of mods that include;

Prc stg 2.5 5.3L heads w/ 59cc chambers (11:1)
eps 226/234 cam
comp 7.4" pushrods
Fast 92/92
slp lid
Ford #30 injectors (36@ 58psi)
pacesetter lt's w/ ory and magnaflow 3" catback
homebuilt 4L60E
4000 stall converter
3.23 rear gear
26" 275/55/15 mt drag radial
15" weld prostars
SD tune


My best run of the night (92 degrees in Dayton, Ohio)
12.07@110.81mph
7.64@90mph 1/8th
1.65 60'

My brother was running a firebird with an lq4 and zo6 cam. While he only had a best of 12.88@108mph, he picked up 4 more mph on me in the 8th mile. He's giving up around 100rwhp to me as well. Does anyone have an idea where my mph is? I believe that I should be trapping 115+mph. Help!

BlackScreaminMachine

iTrader: (17)

There are going to be many factors that influence this but with auto cars I would not worry so much about the MPH as much as the ET.

110 does seem odd but again I would ask.

What track, and on what day. To figure out the air quality.
http://www.dragtimes.com/da-density-...calculator.php input and go.

What was the Race weight with Driver, could be just heavy cars.

Has any of these cars been dyno tuned and verified how much power they are making.

IF all is ok, then could be transmission related, be it mechanical or tune related.

Just throwing some things I see in front of me.

Stippy17

iTrader: (5)

Your not far off from me.

Patriot Stage II 227cc Heads 59cc Chambers
224/230 Comp Cam .581/.592
LS6 Intake
Ported Throttle Body
SVO 30lb Injectors
Built 4L65e
3600 Stall
3.42 Gears

I've ran a best of 11.76 @ 114.8, but my average is high 11s @ 112-113ish. What does your 60ft look like? My setup would perform much better with steaper gears but the car is primarily my daily driver. I suspect your gears are holding your mph back. Do you know what rpms your at when crossing the traps? Also. Has the car been dyno tuned? What's the whp?

The DA probably was shitty and that effected the cars performance as well.

thunderstruck507

iTrader: (18)

110 in an auto in the heat/high DA isn't terrible based on my personal experience

try again in the cool air and I bet you like your slip a lot more

cabech984

iTrader: (11)

I plugged in the track conditions into the calculator linked above and the da was 3570. Im thinking that ill like my slip as well. The car made 410rwhp and weighs close to stock weight, if not more with the 6 point installed. I usually got in the 1.6x 60ft range.

thunderstruck507

iTrader: (18)

Yup, looks like it should be mid 11s @114-115 or so. Not bad for full weight at all IMO.

Probably be a good thing you have that cage

murphinator

iTrader: (2)

as soon as I saw the 92*I knew what the outcome would be at the bottom of the thread lol go on a nightin the 40's or 50's with clear skies and low humidity and I bet you knock off well over 1/2 second and get your traps back.

TA1364

iTrader: (11)

What are you shifting at?

There is 2 mph and an easy tenth with one of these
http://www.speedinc.com/cont.cfm?cid=C0000984

Stippy17

iTrader: (5)

Yeah just like I thought that DA is shitty. Go on a night when its around 2000 and you'll do much better. Your 60ft is on par tho.

But again, do you know what rpms your at when you pass the traps? Your gears are probably effecting your mph like mine are.

cabech984

iTrader: (11)

I wanna say its shifting at 6400 rpm, but im not 100% sure, have to check the shift points, and I have no clue what rpm im at while going through the traps.

I've thought about getting the ram air kit, but all my free money is going into my house and school at this time. Maybe ill look into changing that lol.

FlatBlackZ28

Sorry for the hijack. Just had a quick question about the ram air kit. What do you think i could pick up on my auto LT1 if i switched to an LS1 lid with the RAM air kit?

c0ncEpT

iTrader: (4)

You log the run? What RPM did it cross the traps at? Whos converter?

What was the DA at the time of the runs?

cabech984

iTrader: (11)

No logs or knowledge of RPM @ Traps, but I'll be doing that next time I make it to the dragstrip. Forgot my laptop at the house! The converter is a Transmission Specialties 4000 Stall, I think it'll be coming out this fall in favor of a Circle D 3600 or 4000 stall, not 100% sure, though I am sure it'll be getting pulled(damn input seal is leaking)

The DA was between 3250-3600 that night, my best run came around the 3250 range.

Mike Morris

iTrader: (55)

I think your shiftpoints may take some looking at.

z28241

iTrader: (13)

OP do u have it commanded to shift @ 6400? mine is and w/4000 converter its running out to 6850, we found a balance since theres a run out, so its now how we like it..also that DA is killing u!...wouldnt worry so much until its fall..the 3.23"s and looks to be, taller tire combo might hurt a little as well..good luck, keep us posted

z28241

iTrader: (13)

edit, i see ur on 26" tire so not much different than stock height, DA and 3.23's and stock weight, and AGAIN I'll Say way crappy DA!..ur not far off..

fly pantera

iTrader: (9)

first thing i would do is atleast put a 3.73 rear gear in it,and figure out your raceweight

RealLiveMD

iTrader: (1)

Is your y pipe banging, May be pulling timing on the track. I'm guessing that's my problem Same problem but I have even more hp.

z28241

iTrader: (13)

^^ yes could be throwing alot of knock retard as well, throw the laptop on it..

cabech984

iTrader: (11)

Will definitely check all of the above next thursday at the track, if I make it out there.