My Delcoed Rides

[VL400]

Well done, bet you were pretty stoked after that run

And your log with AFR near on perfect is just showing off

[v6bucket]

Great stuff. Gotta be happy with that.
If you can get the 60' down a little(1.7-1.8s), should be a 12.7s in it. Maybe try 1 or 2 psi more in the tyres, it sounds like the revs a down a little with that cam.

[Holden202T]

well yeah i have spent alot of time on it!! i am still battling with the low rpm bit but its getting alot closer now!

yeah well i started with 12 pounds in the tyres after the first run but it just kept going up as the tyres got more heat in them after each run, so maybe i need to start with less in them and see how that goes ....
i'll be honestly, i have never used slicks and pressures to run them is all trial and error for me at the moment.

what do you mean about the revs being down ? its revving more than it ever has!!

[v6bucket]

The top end revs look & sound good, when you nail the pedal it sounds like the motor is a little "boggy", then starts to sing about the 60' mark. By increasing the tyre pressure, you will induce a little bit of wheel spin allowing the engine to come up onto the "cam". 12psi sounds pretty close, what does the car weigh with you in it?
This is another Gem with a 202, but with SU's, the convertor has a pretty high stall, but when she nails the pedal, the revs are straight into the "cam".
http://www.youtube.com/watch?v=L49eiYmcRG0

[Holden202T]

yeah i think i need a bigger converter really, but i like your idea of pumping the tyres up to get just enough wheel spin to get it off the line.... i will have to fiddle with that next time i go.

its funny actually i did my first run which was the fastest for the night, and i got just a little bit of wheel spin off the line so i thought i'd drop my tyre pressures a bit to see if it was better and yes it was better for grip, but my times went down hill!

the guy who owns the dyno i had my car on reckons i could nearly go to 4000rpm converter ..... thing is do i spend near on $1k to get another 1-2 tenths or do i settle for it as it and put that money towards the LS1 conversion!

still lots to think about and learn

oh yeah and i went on the scales at scrutineering, 1124kg with 30ltrs of fuel and me as it races.

[v6bucket]

The convertor looks like it's hooking about 2700-2800 rpm, which is a bit low for that cam, somewhere 4000-5000 rpm would be better, but that's better left for a convertor expert to pick.

[Holden202T]

its actually about 2400-2500 so even worse

[delcowizzid]

are you just stomping the gas on the light .you need to stall that shit up as soon as the first orange lights up hand brake hard on and foot on brakes,foot hard on the gas all the way to the floor then let it go on the last orange tire pressures down untill it grips launching at full throttle.she sounds mean mate and the times will be there especially if you sort out the rear suspension bars you can see in the burnout that the mounts are off or you have a rooted bush it doesnt do straight burnouts so it will not launch straight and true with minimal wheelspin and torque loss

[Holden202T]

ummmm no handbrake in this car had to cut it out of the floor to fit the commodore front uni joint/yoke in the tunnel!

yeah also i can't hold it on the line cause the fronts just slide, but i do want to try and stall it up more on the brake, just need to press it alot harder and have a few trial and error runs i think to see how i can improve it.

as far as suspension being out that wouldn't surprise me, home made upper arm mounts so anythings possible i want to evntually make some adjustable arms for it so i can fiddle with that stuff but first i need to get the right springs in the rear to stop it squatting so much!

[VL400]

You dont always want to stall it up hard into the convertor, having it below the stall lets it flash higher and give a harder launch - but you really need a higher RPM convertor. Have played with all sorts of ways to get this right and the best 60' times on lower HP cars and 12P is using map a/b to switch off the brake pedal or trans brake. Have map b with heaps less timing so that at WOT it holds the RPM below the stall speed (makes it much easier to hold on the brake too) and as soon as the pedal releases it flashes past the convertor with its new found power. Works a treat and was getting 1-2 tenths better 60' times, and without risk of creeping on the line.