BLK02WS6

iTrader: (2)

I've been following this thread and didn't get that either??

Also, several of us locally are having the exact same KR issue. Something said above I am wondering about - you said excess fuel in the chamber could do it. What would cause that? Could a big lopey cam with a good bit of duration do it? All of us that are seeing it have rather large cams.

It is not the Y-pipe or anything like that hitting - I have been over the car with a fine-tooth comb.

I'll keep watching to see what other input comes. Thanks!

PewterZ28

iTrader: (1)

I don't consider the C1 to be a big lopey cam and that's what I have. Also, in my case, I have true duals and they aren't touching anywhere.

The weird thing is last Wednesday I put in one gallon of 110 octane, drove straight to the staging lanes, did the burnout and made a pass…still 3.9*KR tapering to about 1*KR. Therefore, I assumed it was false KR. Then on my very next pass (after bumping the timing) I got zero KR. Now I'm not so sure it was false KR. Arrggh!

Is it possible it just took the 110 octane a little while to mix with the 93 octane? It seems like the burnout itself would be enough to get the new mixture into the fuel lines.

Maybe I'll go to my Chevy dealer and pay for the induction cleaning service. I hate pissing away money though, that's pretty expensive.

V6 Bird

iTrader: (15)

I was stating that you shouldnt run the rears on different settings. It will cause you to fight the car down the track. The airbag could be deflated and with the rears stiff like you had them you would never see a difference with it inflated or deflated. Thats why you have the shocks at a stiffer setting. I only used the air bag when i had stock shocks that i couldnt adjust, FYI. Even if the car leaves a hair higher on one side in the front its not hurting your 60 enough to worry about it yet.

Line like wouldnt hold any the car much more unless you went to a taller tire in the front for more rollout. IE a 26 to a 28. Then the car would 60 a littler better there too. More roll out before the beam is completely tripped.

A solid sway bar isnt really that much helpful on the line. Its down track where it comes in handy. Keeping your car straight. Gains are sometimes seen on the 60 foot area but its mainly for down the track. Call Wolfe and Ask Dan himself.

Mike

V6 Bird

iTrader: (15)

The higher the DA level is the less air that you car can intake. With that said you will have a fatter A/F ratio on the higher DA's. You can do a few things to fix that depending on what your plugs look like and the plug you are running.

One is to add timing to burn the excess fuel. the other would be to lean the car out a little bit in the WOT fueling tables. Reading plugs will tell you alot about whats going on with or without a dyno. Timing is very important. Just as crucial as fuel is too. KR is happening for a reason and you gotta figure it out.

V6 Bird

iTrader: (15)

Read what i just posted and maybe it will make a little sense to you.

Just by putting a couple of gallons of 110 in the tank though isnt goign to cure the KR. When you muix race gas with pump gas in the tank it dilutes the 110 ALOT and the fuel in your tank is only a few points higher than what it would be with pure 110 in the tank. Understand? So you would only be seeing about 94-96 octane instead of 93 whereas pure 110 on an empty tank would be closer to 110.

PewterZ28

iTrader: (1)

OK, I'm with you now. Assuming the KR was coming from excess fuel igniting outside the cylinder, by increasing the timing I caused the fuel to be completely used in the cylinder, i.e. no unburned fuel to be ignited later which in turn was causing the KR. I'll keep logging data to monitor that situation to be sure that is what it was.

What should I be looking for on my spark plugs? Black suitt like color? I have 17,000 hard miles on my stock plugs but I have NGK TR55's waiting to be installed along with Taylor 10.4 mm wires.

Quick air/fuel question...I benefited from increasing the timing so theoretically couldn't one increase the fuel, then the timing, then the fuel, then the timing, etc. etc. thus continually adding more timing and more fuel to get more power? I obviously am not going to do this but I'm just curious what determines the point at which you have to stop doing that? Is it the amount of air you can bring in? Cylinder pressure?

No more questions after this, I promise.

BLK02WS6

iTrader: (2)

This is starting to make sense to me too. My car is running only 24 degrees of timing at WOT - maybe a degree or two would help? Also, it sounds like leaning it out a little in the lower RPM ranges may help too. Mine is 3 degrees KR right on launch and then pretty quickly decays down to nothing.

I will go to the track and try adding 1 degree and log it and see if it helps - if it does, I'll try one more degree and see what happens. Another words, make small changes and log it. Then I'll try leaning it out down low, but leave the fuel alone up high where it is burning well.

Just seems odd to add timing when you have KR?!? But I understand why from what you are saying. Maybe I gotta have 2 tunes - one for cool weather and one for the heat.

Does it sound like I'm on track?? Thanks for the help V6 Bird!

ATVracr

iTrader: (5)

Good stuff!

BLK02WS6

iTrader: (2)

Wayne, I sent Jeff a PM to read this !! I hope he goes to the track tomorrow and/or Saturday with the laptop. Wonder if the Edit is back up??

GrannySShifting

iTrader: (10)

you know what were gonan try only matter is when we go racing!

H82BBad

well as far as tuning. When you increased the timing by programing. It reset the fuel trims. So if you had positive fuel trim's from driving around and it was fueling to much (.950) that could have been partially at fault. Adding timing will also lean them out a little from what I have seen.

PewterZ28

iTrader: (1)

So I guess getting your LTFT's to negative 1 is still the starting point? I used to visit the PCM section but got too nervous when the "correct way" of tuning was constantly being questioned. I figured if the pros couldn't agree on the dos and don'ts, I sure as heck wouldn't be able to figure it out.

Two years ago I got my LTFT’s to average in the –0.5 to –2 range. Then on the dyno I used the Fuel by RPM table to add or subtract fuel to get the air/fuel curve flat and where it needs to be for an NA engine. I did gain about 5 rwhp/ 5 rwtq from it but I never did touch the timing so perhaps there was a little more to be gained. However, I soon put it all back to stock when the slightly negative LTFT method was starting to be questioned in the PCM section.

I’m still curious about my question on adding timing and fuel. What is the determining factor on how much fuel and timing you can add? Obviously there is a lot more to tuning but for a guy like me who doesn’t know too much, is there a basic rule of thumb to follow when it comes to adding timing and fuel?

BLK02WS6

iTrader: (2)

If the gates are open - I'll be there - pray for no rain!

V6 Bird

iTrader: (15)

I personally dont run any plug that starts with the letters T and R.

T= Terrible and R= Race. Together they are terrible race plugs!

When you are reading plugs you want to look at the strap and see where the line is. That indicates your timing and then you look at the porcelain (white inside the plug) for speckles and color. Light gray is what you are looking for btu then again its pointless to read a TR series plug. Those are expended tip plugs and falsify all the readings.

I personally would suggest running a r5671a-7 for NA and then step up to a 9 or 10 on the juice. These are NGK plugs that fit our cars. Just be sure to tighten the plug a half turn after its snug to seat the gasket. Gapping on a 7 or 8 for NA use i would recommend .030 gap vs a .038 to .040 on a TR6 or .055 on a tr55. What that does is bring some of the heat back that you lost by going to such a colder plug.

Why do I run these plugs you ask? Pulling the porcelain down into the body of the plug does a few things. Its a colder plug than a TR6 yes but it also pulls heat out of the combustion chamber and allows the car to have a cooler denser charge into the cylinder to make more productive power. Make 3 dyno pulls on a TR6 or 55 back to back and the power will almost always fall off on the last pull. Why? Too much heat trapped in the chamber instead of the plug itself. A cooler plugs like a 7 will allow for more agressive tuning and not fall off on your 3rd dyno pull. Just by swaping in some 8's in my car from a TR6 my car picked up over 15 rwhp. Thats why i continue to run them. Its the fine tuning of a car that seperates it from the rest of the group with the same mods. A good set of wires is a plus. I personally like MSD stuff. Others like rest. Most LS1 heads dont like any more timing than 29 on pump gas and a tr6. Go a step colder on the plug and ive seen 30 at wot be succesful and not have any KR or detonation. Keeping the fuel and air charge cooler decreases your chances of KR sigificantly. Your KR could also coudl have been from you still running your stock platimum plugs. These are heat in them selves. The KR went away from 2 things....The fuel octane rating went up a few points or like what was already talked about, the fuel wasnt being burned efficiently and the increased timing helped to burn the excess. Hope you guys are keeping up with what Im talking about.

Mike

V6 Bird

iTrader: (15)

I use that same mthod with lots of success. Go back to it.

Mike

Vetal

iTrader: (3)

PewterZ28, please tell us now what had given you the most results in these 3 years, that allowed you to get down from 1.57 to 1.34?

PewterZ28

iTrader: (1)

3 years? More like "almost" 4 years.

Man a lot has happened since then. Going from mid 1.5's to mid 1.3's in 4 years isn't necessarily an accomplishment. However, I'm not one to make giant leaps like going from a bolt on car to a 427 with 2 stages of nitrous. I took baby steps, going from bolt on car to a small-cam-only to a big-cam-only to a TH350 big-cam-only setup to a heads/cam setup that I never got to run to finally a 383 heads cam setup. Next year I plan on getting a nitrous converter, dropping down to 3.42 gears, running a true 28" tire and spraying a 200 shot. Right now I'm pulling mid 1.3 short times but I was really hoping to be in the high 1.2 range running high 9's. That's the thing about drag racing, a setup is never fully complete and you are never fully satisfied. We always think that one last mod will get us to where we want to be but it either doesn't or we find out we suddenly want to go just a little bit faster. For me, doing all of the little things is what is most fun about this hobby. Finding a hundreth here and a hundreth there.

I still think my bolt on car was pretty impressive for its weight and gears at the time. With some 4.10s and some more weight reduction it could have easily gone mid to low 11's. But I was already getting booted for not having a cage and I wanted to race so I went out and got a cage and at the same time got some 4.10's and a cam and some more suspension parts. I was expecting to drop at least a tenth off my sixty foot times but I did not and that is why I started this thread way back then. I wasn't really giving my weight gain enough consideration and that was probably the problem. Adding 150 lbs has more of an effect than you realize. So while I took 2 steps forward I also took 1 step backward.

If you want to know more about my current setup feel free to PM me. Nothing special, just all of the little things that add up to big gains.

Vetal

iTrader: (3)

Glad you were watching this topic
I'm just like you - enjoy the process of tuning itself adding little bits and finding gains continuously.
I've just recently bought TransAm, and I don't know anything about it so can't ask questions about your setup now I'm in the stage where I can only ask for ready advices how to tune my car. I don't have any knowledge of TA suspension, how it all works. I bought a car which already had suspension mods, and last autumn I just wasn't getting any traction. Tracks here in Latvia are unprepped at all, and they are very dirty. Guy in USA was getting 12.8@110mph in USA. Here I was freely spinning my MT Streets 26x10.5 x16 AWDs walked all over us, RWD guys.
Maybe you could look in my thread where I was asking for advices, what to do, how to get traction? I really want my LS1 to fly, not to get beaten by all the low-powered AWDs
https://ls1tech.com/forums/street-racing-kill-stories/789299-slicks-use-public-dusty-roads-can-t-match-awd-cars-launch.html

blue99ta402

I have been reading this post and I have a question. I'm a little new at the track. I have stock shocks on my car. I only have a BMR torque arm. My 60' is 1.7 I have MT streets and they work great. I have asked people at the track about aftermarket shocks.I have mixed advice. My car really lowers in the back when i take off.. I'm told that is good because of the weight that falls on my tires when i take off and gives me traction.. But I'm told by others that when your car goes down it isn't going forward. Can I get some advice from you guys? which is better?

PewterZ28

iTrader: (1)

Ideally you would want to hook without squatting too much. I have my QA1's set on almost the firmest setting in back but I keep my fronts pretty loose. The pic below is what happens coming off the t-brake. Tightening the front keeps the nose down but I don't go any quicker in the 1/4 (.03 at best and that could have been the DA or my shift points). Adjustable shocks are eventually a must in my opinion. Use the settings that net you the best 60' and 330' times. That's what I do anyways.