Finally, the 12's

Don W.

Don W.

Stab it and steer it
First I have to give a huge thank you to Josh (Tooky) for some tuning ideas.
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So, went to the track yesterday. It was the last night of racing for ’07. First run 12.880 Woohoo, I’m in the 12’s. And it wasn’t a fluke, next run: 12.805. Speeds were 104.65 & 104.24 respectively. What’s interesting are the short times. This truck can, and has in the past, run in the upper 1.7’s 60’. 1000’ times are good. So presumably there's some more here. The truck felt noticeably stronger on the second half of the track. Times went down later but I didn’t care, I’m there (the 12’s) and I’m a happy camper right now.
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http://www.sonic.net/~donpris/12secondslips.jpg
 
TYTILIDIE

TYTILIDIE

METH HEAD
Re: Finally, the 12's

What were his tuning ideas? Congratulations, must be a hell of a feeling. Especially if its been your goal.
 
TYTILIDIE

TYTILIDIE

METH HEAD
Re: Finally, the 12's

JS Manufacturing said:
Good launch = mid 12.5's
Click to expand...

Maybe I should be asking you this in a seperate area but, is htere a relation to having more mph with not your best 60'? I have noticed this too. I get better 1/4 times with 1.9 60' s than I do with 1.7's. Is there something in the tune being over looked? Or does it just depend on the truck?
 
JSM

JSM

Active member
Re: Finally, the 12's

In general .1 second 60ft will be .2 quicker in the quarter.

MPH tells you how much HP your making, ET is how efficient you are getting down the track. There really isn't a relation to a better 60ft and worse MPH, it should go other way slightly.
 
Don W.

Don W.

Stab it and steer it
Re: Finally, the 12's

Well I think there were four factors working here in about this order.

1) The thought was that I was running rich so I reduced FP from 54 to 45.

2) Since I was showing virtually -0- knock before on T1-18 I went to t2-20.

3) The air temp was below 60* (truck loves cold air as we all know).

4) I removed the spare. 30# +/- what the heck.

Fuel was about 1/3 96 2/3 91, my usual mix. Track was cold as well with the sun going down at 5:00. Considerable rear tire spin at launch otherwise I might have done better to 60'.

This just confirms the need for a wide band o2.

Will a different waste-gate control help with the boost spikes? Seems if I could even out the boost it would be better all around ya think? :roll:

http://www.sonic.net/~donpris/AutoLog_294.uni

http://www.sonic.net/~donpris/AutoLog_295.uni
 
N

NOWAY55

New member
Re: Finally, the 12's

Nice !

I will run some day perhaps. If Anderson ever gets my POS back together.

Anyhow, with my other POS, my BEST 60' has been 2.2 or right around there which really sucks. FWD and I have pulled a 13.4 @ 104.19 what does that mean? If I could pull a 1.9 60' I would or should go 12.8 ?

O well, I will just keep racing from an 80 mph roll then. I can't get off the line for crap.
 
It's just a six

It's just a six

Super Member
Re: Finally, the 12's

Don,
if you are getting boost spike w/zero knock,what is the problem?
When I ran my Pitbull chip I was running 18 PSI & would boost spike,to 20-21 PSI (just for a split second) I would get 2-4 degrees of KR but only on the shifts& like I said,only for a split second.

So if your not getting any knock retard,I do not see much of a problem.
You can port the stock wastegate hole on your turbine housing,that will take care of your boost spikes better.
Or install a larger wastegate valve,but then I suggest a stiffer wastegate actuator.
 
Tooky

Tooky

Serious about performance
Re: Finally, the 12's

Hey Don, congrats! Glad to hear your truck is in the 12s now. :)

I took a quick look at your DM files; you're getting a fair amount of knock, but once you get the wideband we can tell if it's from too rich (too much alky) which is most likely, or if something else is wrong. If you are using the Ultimate's standard wastegate solenoid control, you will definitely see better control with a manual boost controller. The Ultimate's boost control NEVER worked properly for me, it always produced a horrible "roller coaster curve".

I would also rev it higher in 3rd before shifting into OD. I assume you race in "D" like most do, so just click it to OD around 4500-4600. Right now it's going into 4th (OD) around 3850 in 3rd, which takes it all the way down to 2825 RPM in 4th. Good for proving that your transmission and converter aren't slipping!! :) But not as good for top end performance. It also caused a boost spike to 23-24 PSI!

Other than that things are looking good. I bet you're anxious to see how much more you can squeeze out of the truck now, hey? :)
 
Don W.

Don W.

Stab it and steer it
Re: Finally, the 12's

Yup, squeezing a bit more would be veeeery cool. The friends I race with were happy as well. I gave credit where credit was due. Thanks. Yes, I suspect I'm still spraying to much alky.

On the one hand trans seems to be holding up well. On the other I was planning on a rebuild for reliability and possible TC upgrade. Will be researching the WB this week then planning a a post for people's thoughts here.

I've been shifting to OD at the 1000' marker. There or the first trap marker. In bracket racing though some of that can get used for braking, but that's another topic.

What do you think of some sort of shift light setup so I could launch at the same RPM consistently?
 
Tooky

Tooky

Serious about performance
Re: Finally, the 12's

Don, I honestly would make a strong recommendation to NOT rebuild your stock trans or TC until they wear out. Time and time again I have seen it proven before my eyes that your original stock SyTy transmission will be the BEST transmission your truck will ever have. All transmission rebuilds/upgrades carry with them an extremely high risk of not performing "just like your stock one", in fact the pressure changes necessary in a build trans ensure that no built transmission will operate identical to your stock one. When I upgraded mine it turned into 3 hard years of hell trying to get it to shift as nicely and correctly as my stock unit did. And you'll be lucky to get 1/3rd the life out of a built transmission compare to your stock one. I think I had 2,000-3,000 launches and WOT runs on my original transmission before it failed (including 200 miles of road racing).

In the case of the stock transmission my advice is "If it ain't broke, don't fix it!". I have similar feelings about swapping the stock torque converter out. The stock transmission works best with the stock converter. :2cents: I am sure not everyone agrees with my advice but I'm just speaking from my personal experiences...


As far as launching at a consistent RPM. What some of the faster trucks are doing is buying an MSD Digital 6 ignition for it's built in "2 step rev limiter" feature. You can set a 2nd rev limiter at low RPM (say 2200 RPM) and then you floor the gas pedal and it will stutter on the line and cause boost to build (even in Neutral!). Then you just release the brake and the 2-step switch at the same instant, and presto: consistent launches!

I actually bought an MSD Digital 6 about a year ago for this reason but still haven't found a good place to locate it so I have never installed/tried it.
 
Don W.

Don W.

Stab it and steer it
Re: Finally, the 12's

Interesting on the trans. It sure would save a ton of money, er, to spend elsewhere on the truck.
icon_biggrin.gif
BTW The answer is kinda obvious but what's your thoughts on a aux trans cooler. Reason I ask is last summer it seems that as I made runs my times would slow down and the only thing I could attribute it to was the trans getting hot.

I have a MSD 6al which allows the use of a "2 step." To go that way I'd have to change classes at the strip. Currently I run Sport Street which does not allow electronics like the 2 step. Hence the question on the light. That or move over a lane and run with the big boys in comp rod. Which I might consider actually. Tougher, meaning more experienced, class but not near as many cars.
 
dgoodhue

dgoodhue

BuSTeD 4.3
Re: Finally, the 12's

Don W. said:
Interesting on the trans. It sure would save a ton of money, er, to spend elsewhere on the truck.
icon_biggrin.gif
BTW The answer is kinda obvious but what's your thoughts on a aux trans cooler. Reason I ask is last summer it seems that as I made runs my times would slow down and the only thing I could attribute it to was the trans getting hot.
Click to expand...

I would use a tranny cooler and deep pan. A higher stall converter may help with with the launch (ie you might be able to get away without doing rev in N to build vacuum), but it will create more heat and could potentially shorten the life of your trnasmission as a result.
 
turbodig

turbodig

Active member
Re: Finally, the 12's

Don W. said:
Interesting on the trans. It sure would save a ton of money, er, to spend elsewhere on the truck.
icon_biggrin.gif
BTW The answer is kinda obvious but what's your thoughts on a aux trans cooler. Reason I ask is last summer it seems that as I made runs my times would slow down and the only thing I could attribute it to was the trans getting hot.

I have a MSD 6al which allows the use of a "2 step." To go that way I'd have to change classes at the strip. Currently I run Sport Street which does not allow electronics like the 2 step. Hence the question on the light. That or move over a lane and run with the big boys in comp rod. Which I might consider actually. Tougher, meaning more experienced, class but not near as many cars.
Click to expand...


Does your class allow line locks? Do a 4-wheel line lock and hold down a button.

Rig up an audio system off the tach pulses and a set of stereo headphones. When the tach frequency matches your set frequency, you'll know you're at your launch RPM. Your eyes never leave the tree.

Lights come down, let go of the button, and you're off.
 
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