12.9 with 347

yeah, that is a pretty bad time!!!!! you could have thrown a set of gt40p heads on and gotten better than that!

Kinda what i was thinking.

the mph is good for 12.60-12.50's

the 60' isn't bad, you could knock about 2 tenths of fit, at least 1 tenth. i'm thinking get in the 1.68-1.72 range and you'll see 12.60-12.70

cheap way to hook a little better is an air bag in the right coil, use 8 psi in it, $30 and about an hour of your time.

what lca's ?

shift rpm ? are you shifting off the stock tach?

at least use a light, try a 5200 chip, then 5400, then maybe even 5600 but wherever your mph is best use that chip as your shift point, remember when the light comes on, it will take about 300 more rpm for you to complete your shift.

timing ? are you at 14*-16* and using 92+octane ?

i think you have more mph out of it too, should trap about 110

110 mph shows about 300 rwhp in a 3200-ish pound car

my old notch w/ stock motor 4.10's and 75 shot went 12.52@ 108

so that should be a fairly comparable time to match

Sounds like driver error. Just time and practice.

Edit:: What rpm were you at when you went through the 1/4.?

He still should be running ALOT faster than mid 12s! My 331 with c9 heads is running 12.0s@113 , he should be doing ALOT Better, like high 11s!

E.T. doesn't matter as much as mph. Mph shows potential...

That mph still isn't very good for what you have, just practice with shifting...

Driving should help that a TON!

i think is driver problems and the other thing is i think you are little short go down to 3.90 or 3.73 gears and get out of the hole at least 4500Rpm's 3k is too low

You may want to take as much weight out of the car as you can, back seat, spare, junk in the trunk, etc.

The mph says you have some et to gain.

You may also want to try a couple dyno runs and check the air fuel ratio, etc, and adjust the timing to what runs the best.

i agree with the driver practiceidea....even my vert 347 went 12.50's @111mph on nitto555r's witha 2.0 60foot....def launch harder...if ur suspension is up to par.....powershifting thru all the gears will sure take some off that et as well.....and yea i would run between 11psi and 14 psi in the tires