zippy

My attempt was the why the hell would you do it that way, it was that there are other solutions. My comments were directed at the topic at hand which is 60' times. I'm glad that your way works well for you. The way you have it set since you are running a throttle body with a cable your way would probably be the easiest to run the truck in a bracket racing type situation. Something I don't understand though is the slicks part. If you bolted slicks to it with the timing back into it you should have been able to be putting down much more power at least in the first 60' to 100'. A Radix'd 5.3L should have a flash stall of around 2400-2500 with the stock pulley and all the timing you can get into it. Here again I'm not insulting or picking at you. I'm simply saying that you might have been able to gain more with the slick's and should have if you'd worked at it.

Obviously tuning for a 2wd truck and an 4wd/awd truck is different. Your tuning would also be different between running street tires and slicks. The best 60' times I've been able to squeeze out of Radix trucks have been on off idle launches. If you were tuning for a truck with an electronic throttle control you'd be able to obviously tune in how quick and how far the throttle blade opens by RPM. (which btw, just pointed out to me to check Holty's, the guy who just put the 90mm throttle body on and the previous tuner really went at it in there). If you're tuning for a little less torque and using a cable drive setup and you're running a stock converter my suggestion would still be an off idle launch and changing the timing curve down low to reduce the stall speed. This in effect would be alot like launching a manual trans car and bringing the clutch out at as low of an rpm as possible. I'd try to fade the timing down low from about 800rpm to 1600 and slowly fade it back up 1 degree at a time fading it back to full by around 3200rpm. By this point the weight transfer should be in enough to keep the tires hooked up. If you have a half way decent transmission you might also leave in a bit of the torque management to keep the tire spin down on the 1-2 shift. You could also bring the power enrichment in early at around 35% and richen it heavily to around 11:1 between 800rpm and 2400. Another way I've found to limit the torque converter stall speed and make the launch softer was the run a lower number in the torque management maximum torque vs. rpm. That is one of the easiest ways to make for a consistant launch. Without ever chaning the timing table or any of the other you could adjust this at the track depending on how well the track is hooking that day. Simply put in something like say 300 from 3200rpm and down. Each pass you can slowly fade the number up and the computer will take out the timing needed to keep the torque down. Basicly it would be a way to limit how much torque the tires can handle being put to them at the starting line. On a 408 truck I was doing some testing with I was able to change the stall speed up or down 500rpm by making changes in that table. Just another way and another idea to work at the launch.

BlownChevy

iTrader: (20)

kinda my point to begin with

Crash Dummy

Lets please keep this ( Timing at Launch) thread on the subject if anyone wants to start a torque management launching thread feel free to do so. I feel what was a good thread about a simple fix to traction problems at the track has now been destroyed. Timing to control launch has been used for years in drag racing and MSD sells computers for just this reason. This is a simple and understandable way to do it for some and a good way for people with non electronic t- body's. If this thread does not stay on the subject ( timing at launch) I will lock the thread and delete any non related post.

dewmanshu

iTrader: (4)

Kinda finding it hard to post in my own thread due to the bad pick for a topic. Didn't mean to put such restraints on the topic.

WOW crash, your experience is almost my age! LOL

I still ask one of my main questions, what if any harms could come about with the IAT correction table. I understand the negative timing, well, I take that back, I sorta don't understand it but I see how it works...I have no diect knowledge of it besides I have always assumed that's how "launch Control" works (along with rpm limit) on alot of add on products. I do feel in this thread that Zippy questioning the "spark plugs fouling" is a good subject for this thread (or any issues with negative timing), I want to see which way (more than 2 ideas is good to) is safer..obviously respecting just staying stock is the safest. "F" stock.

Let's say my IAT correction table (for arguements sake I am only gonna talk about .92g/cyl down) at 14 degrees I add alot of timing, 6 to 8 and I phase it down to zero at 104*. Then from there, I go negative at 113* (-1*), 122* (-3*), 131 (-4*), 140 (-5*)...You get the picture, at 185* I am at -9*. Too me this is no more dangerous than someone tuning there actual spark tables. I guess some will have issues with they are almost never getting what theiy are commanding in spark except when their IAT is at 104*. This technique can be modified depending on if you are living in Maine versuses Arizon obviously. I don't see any problems that can arise the way, besides if traction is your problem, you may not like this idea.

The problem with the thread is what works for you might not work for me (2WD vs 4WD). I understand this, so my question is...my tune, my (zippy's idea) IAT correction, is it bad for some reason, dangerous? I don't favor anybody here either, I hate everybody the same.

Crash Dummy

IAT is the most unconsistant thing in a blown application and can not produce any consistent times using it . The IAT table is used for engine protection more than anything else and yes it can be used to add or take a few degrees of timing to help HP a little but unless you run the exact IAT every run you won't be consistent. I had a friend do the timing on his GTO and he went from 12.6 in the quarter to 11.8 and Blown Chevy, my friend or myself have never experienced any plug fouling or anything that resembles it. This will only work for vehicles with major traction problems , my tires would start spinning at 40% throttle before and I used this method as a cheap quick way to fix the problem on my work truck at the track because I do not want to buy any other tires or put any traction devices on it. The nice think is my 100000 mile 5.3 still has the original trans in it and I only paid 8000.00 for it and the blower was free , so basically my 100000 mile 10000.00 dollar truck is a half second faster than a SRT-10 and 1 second faster than a lightning at a whole lot less money and very consistent using the basic timing launch. Just cheap easy fun!

zippy

If I want to post about using the torque management as a way to control the 60' time, then I'll post that. It is certainly on topic and if you don't like it, too damn bad. You don't get to decide what is on topic and what isn't. It seems here that anything that you didn't post you seem to have an issue with and think that there should be another post on it. Using torque management in the 60' to control the launch is very similar to reducing the timing manually, except that the computer gets to decide how much timing to pull and would be much easier to do for someone not very experienced with it.

The tuning in the IAT table isn't something that offers consistancy and isn't meant to be. You can run consistant times with it as long as you allow for the same cool down times between runs each time. On one SS we ran 3 passes within 1 tenth of each other and probably would have been more if we hadn't made some changes to it after that. Running consistant times are for bracket racing vehicles. I've seen guys at the track when the air is getting cooler go in and add timing because they think the air is good enough for it. If you already had that in the tuning you wouldn't have to touch it. Unless you had a failure of the IAT sensor you wouldn't have to worry about it being harmfull as it's only going to add the timing when the air is cool.

moregrip

iTrader: (8)

leave this commentary to a PM please, challenging any mod in this manner will not benefit you.


He absolutely does. If you have a problem or concern address it via PM with CrashDummy first, work it out that way, if that does not meet your satisfaction, take it to another mod or admin. Posting these comments doesn't do anybody any good.

TIM Z

iTrader: (12)

i can see 2 guys here that are passionate about what they know and thats cool as well as helpful. But it seems that Zippy's replys are bieng judged unfairly. I dont have a radix but have just learned a bunch from this post. lets quit bashing contributing posters here.

XLR8NSS

iTrader: (4)

Let's just keep this thread about the subject title "Timing in the 60' Launch".

If someone wants to start a thread about the IAT or torque management method please do. It's better if things like this are in their own threads because when someone comes along and does a search it's easier to locate the info they want. They don't have to sift through a thread that's supposed to be about timing to find something about IAT, etc.

moregrip

iTrader: (8)

what I commented on is innapropriate, period.
there is right and a wrong way to handle these things, especially when they start to escalate. That's the end of it.

with that said, lets keep this ON TOPIC from here on out. If you feel you need to express your personal opinion outside of technical merit please do so via PM, thanks.