Why is my a turd in the 1st 1/8th?? Then big MPH??

[JA$ON]

Why is my car a turd in the 1st 1/8th?? Then big MPH??

I posted this everywhere already, so sorry if youve seen it, but just looking for some local feedback.

Went to the Real Street Drags last night at a local track. My car has - modlist: Bogarts front & rear, 26" ET Streets @ 12 psi (cold), DFX Clutch, Fidanza flywheel, built solid axle (33 splines, 3.90 gears) all spherical bearings on axle side , Tokico Drag struts (set on 2), B springs front, Pro3i weight jackers, CHE adj uppers, bullitt springs, 10 way Strange Adj shocks (set on 5 clicks), Accufab T/B, 2400 MAF 2.76, Steggy IV port, Magnaflow catted X and C/B. I think thats all the power mods, I dynoed @ 510 RWHP & 475 RWTQ SAEand a pretty soft tune (in the 10's A/F from 3-5000 RPM).

I launch @ 6K and was 60' ing in the high 1.5's last night, pretty much every run was 7.32-7.40 in the 1/8th but traps were only 90-91 MPH, then 1/4 ET's were in the high 11.4's and traps were right around 123 every run. So I was picking up 30-32 MPH consistently, it did this every run, whats going on??

I know when you launch hard and hook, it will bring down MPH, but I think I trapped higher in the 1/8th before the port and solid rear!!

Do I need to look to my suspension setup, I have never set the pinion angle, maybe that needs to be done , or adjust my shock/struts??? It seems like 123 MPH is a pretty good trap with no lower, but that soft first 1/8 is leaving a lot of ET out there

Also to consider, what RPM do you carry 1st gear to, I am shifting right @ 6K every gear, I think some guys run out 1st a little longer, maybe 6200-6400, and then powershift.......must....not.......lift.....gas... . the 1-2 shift is everything!!

Thanks for any ideas,
Jason

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[Wiked03]

First of all.... Byron. This Sunday. Be there.

Ok, I think you may need to start shifting higher. Did you get a shift light yet?

If it were me.... With the port I would spin it a little harder and see if that changes anything.

I would try and set the shift light to like 6200, I would also try to carry 1st gear a hair longer, like to 6400.

Are you still bogging a lil on the launch?

What are your 330 times looking like??.... it is almost looks like you are losing some time on either the 1-2 or the 2-3 shift.

Last time out I was actually having the opposite problem..... I was trapping 95 in the 1/8, but only 117 up top.... though I also desintegrated my CFDF that day, so I dunno

 

[gnxs]

Jason, raise your shift points (6200-6300 at least). If you don't have a shift light yet, GET ONE.

The tq. loss that occurs with the ported blower may account for the relatively poor performance in the 1/8. I think with a 2 lb. lower you'd be right where you want in the 1/8th, but then I bet then you won't pick up as much in the last 1/8th mile. However, I still think the extra tq. of the 2 lb lower would get you close to a 7.0 1/8th mile (and a 10 second timeslip). I'd also get that tune tweaked so you see at least 11.5 A/F up top. You're losing ALOT of tq. running an A/F in the high 10's.