Where to Shift RPM wise at the track w/ my mods? DarkFire , anyone??

[xtweakerx]

Engine: 4.6L
GMS Driveshaft Loops
Hurst Line-Locks
5 Speed Transmission
Ford 4:10 Rear-end Gears
Brenspeed SCT2 Tune 93 Octane
Steeda Under Drive Pullies
C&L "Racer" Cold Air Intake
Steeda Upper & Lower Control Arms
M&H 275/50R17 Drag Radials
Pypes Off-Road H-Pipe
Flowmaster Axle-back Exhaust


I have been shifting at 6200. Lend me your thoughts.


Disappointed with my last time out at the track however it was god awful humidity 80% plus and temps 77&higher and also the first time back in the car racing in 6months at a new track plus i was testing out different tire pressures.


But i ran back to back 13.23 @ 104 w/ 1.90 and best of the night 1.87.



i plugged my values into Density Altitude calculator and it said 12.99 corrected whatever that means.. ; ) Hell im gonna go race this saturday should be great weather so ill try again, should i shift higher than 6200?

 

[DarkFireGT]

Redline for your tune should be set at 6800. I shift around 6400 and don't take my foot off the go pedal.

 

[chad9350]

Where are you rpm wise when going through the traps?

Maybe try a little above or below 6200 on diff. gears... i wouldnt be surprised you find a tenth or two hiding under your nose!

FWIW... it'll be fun trying to find!!

 

[DarkFireGT]

Yeah, what gear are you going thru the traps at, and what RPM? With that gearing and tire size, you should be staying in 3rd and crossing just under redline.

 

[kevanp]

Redline for your tune should be set at 6800. I shift around 6400 and don't take my foot off the go pedal.

+1

I trap in 4th @5800 ish.

 

[xtweakerx]

+1

I trap in 4th @5800 ish.

so u shift at 6400 as well?

At what RPM are u launching at?

 

[kevanp]

tweaker,

I'll power shift at 6200-6400.
I typically do 6200 on 1-2 and 2-3 and 6400 3-4.

I launch at 2500rpm on street tires and 5k on drag rubber

The 2 biggest things I had to work on to get sub 13sec times was traction at launch ( needed tires and front swaybar removed) and power shifting (took practice)

 

[kevanp]

Yeah, what gear are you going thru the traps at, and what RPM? With that gearing and tire size, you should be staying in 3rd and crossing just under redline.

I would doubt he traps in 3rd with 4.10s

 

[DarkFireGT]

I would doubt he traps in 3rd with 4.10s

We had 4.10's and M&H's on our '05, along with intake, tune, off road pipe, etc... and we were trapping right around 6k in 3rd. It is possible. M&H's are tall tires. They bring the effect final drive ratio down to about 3.90.

 

[xtweakerx]

hey im going through the traps in 4th gear, i tried running 3rd gear out but i hit the rev limiter before i could make it , i tried it once because 4th gear is not long before the traps, but that was when i was shifting at 6200, so maybe shifting at 6400 will give me a bit more room to maybe make it in 3rd, i dont know its gonna be close though ; ) lol


wish me luck im going to go race saturday..

 

[69mach1-409]

I have 3.55's and I'm just hitting the rev limiter (6500) in 3rd going through the traps.. are the DR's making that much of a difference that you can run 4.10's and still stay in 3rd?

 

[xtweakerx]

the height difference does make a difference i think its dropping the 4:10's down to 3.99-4.0's im not sure about all the way down to 3.90's that is a bit much.

From my experience I dont think I'll be able to run through the traps in 3rd because i tried it once already ; )

But i will say I don't believe i trap that high in 4th , but heck when i run this saturday ill take a look at my Tach to see what im trappin at, i got a GOOD Feeling about this Saturday as long as the weather holds up.

 

[91frppgt]

after my car got tuned, it never see's over 6200.

i believe its 6200 from 1st to 2nd, 6k 2nd to 3rd, 5,800 3rd to 4th, and converter locks up early.

my best mph is 108.54 with a auto, basic bolt ons and tune. on 20's as well.

i thought you 5 spd guys would be trapping higher?

 

[kevanp]

after my car got tuned, it never see's over 6200.

i believe its 6200 from 1st to 2nd, 6k 2nd to 3rd, 5,800 3rd to 4th, and converter locks up early.

my best mph is 108.54 with a auto, basic bolt ons and tune. on 20's as well.

i thought you 5 spd guys would be trapping higher?

I trap at a lower mph when I get hook and a good ET.

 

[UrbanRedneck]

I trap in 3rd gear at like 6500ish with stock 3.55s and stock tires... I have 4.10s waiting to go in, but I fear they may slow the car down at the track because I wil have to shift into 4th. It will be fun on the street though.

 

[xtweakerx]

urban, i have 4.10's and drag radials and i npw shift into 4th and im going faster now than previously.

 

[SinCityVogel]

I have 3.73 gears and i shift at 6000

 

[fullboogie]

If you look at the hp/tq curves on a dyno graph, you will be surprised to see where the peaks are. In my opinion, shifting at 6000 or above is way too high for a basically stock engine. Personally, I set my shift light for 5500 to shift in the 5700-5800 range (taking into account reaction time for the shift light). I think there's a misconception about how high these engines need to be shifted for max ET.

 

[kevanp]

If you look at the hp/tq curves on a dyno graph, you will be surprised to see where the peaks are. In my opinion, shifting at 6000 or above is way too high for a basically stock engine. Personally, I set my shift light for 5500 to shift in the 5700-5800 range (taking into account reaction time for the shift light). I think there's a misconception about how high these engines need to be shifted for max ET.

What kind of times are you getting @5500?
I would think shifting at 1000rpm would yield max ET.

 

[ptfoxbdy89]

im in 3rd at about 6300 im runnin way faster than you are?? 106ish at 13.33?? i have a 3.55 in the rear though..