A couple questions regarding my tune on my G8...

[gtp6515]

Good afternoon. I am trying to maintain the power level I am at, and am hoping to get a little guidance. The attached run at the track had a bit of knock (sensors are desensitized some), and I was thinking going w/m injection to cool down the iat's. I was pretty content with the 12.2 @ 117 with just over a 2.0 60 ft, but think there may be more power I have not found. Is there another way to get rid of this knock w/o taking away timing, or going to a 160 stat, which I for some reason feel is not a good mod. I was thinking meth may allow me to run more timing at all times, and not have the car feel like its nuts are cut off when it gets hot in the summer. Snow Performance says it will work well, but they would. Another issue I am having is my downshift from 2-1 seems to buck a little as I slow to a stop. It is definitely not smooth Not sure what this is all about. Anything look suspect in the tune? Thanks for checking this out, and any constructive assistance would be appreciated.

[gn2beatu]

You IAT's are in the 60's. How low do you want them, its not like your running forced induction. The meth will help with the fact that its higher octain, and not only will it kill the knock, but you can run even more timing. Im only seeing 2 degrees of knock.

I hope you realized your far better off power wise with several less degrees of timing than you are of running just one degree too much and causing knock. The LS motors have very efficient heads and dont need allot of timing. You didnt mention what your compression ratio is or what octain your running either. But if that where my vehicle, Id pull 2 degrees of timing for daily driving. Then when your at the track either run better gas, homebrew your own with tollulene/xylene, or add the meth. Either way, get rid of the knock by dropping the timing til you find a better solution. Its also not a good idea to desensitize the knock sensors, unless you have false knock. If you do anything with the knock settings, give the timing back faster (when no new knock is detected).

You also have to look at the area your knocking, and thats at peak torque, where the engine is under the greatest load. Its normal to run a degree or two less there. Something your not doing in the areas of grams/cyl your knocking at. If this was mine, I would adjust .84 - .92 in the 4800 column loose 1 degree, in the 5200 loose two, and 5600 loose one

[gtp6515]

Hello GN. Thanks for your input. I am running approx 11.2 :1, and am running 92 octane. Would 93 make a difference? I guess I am trying to optimize the bucks I have spent on this car. Did it look like it was removing timing when the knock was taking place? I am not great with this stuff, but I am trying to learn. For the knock sensors, I was told that some false knock can be a nuisance with headers as they are so close to the sensor. Could be bs for all I know. I keep toying with w/m injection using ww fluid as it noticeably cools down iat's, and the car would not feel like such a turd in the warm summer weather. Now it is getting into the 20's and lower here now, so done for the season. It is my dd however.

[DSteck]

Meth is wonderful. Go with Alky Control though. Pulling timing and running more fuel are two ways to try avoiding knock.

[sohc_mshue]

Try reducing timing by a few degrees and do some pulls. If you are still getting knock then most likely it is false and you can desensitize the knock control a bit.

[gtp6515]

They are already desensitized some.

[IDRIVEAG8GT]

I say nay to running meth. Might as well put nitrous to it and that'll really give you a reason to pull timing out lol.

All bullshit aside though, everyone's telling you right, too much timing at peak torque. Peak horsepower is spot on. You'd be deep in the 11's if you could get that thing off the line. (I know you're still void of a stall.)

Damn I wish my IAT would get in the 60's!

As Steck said, run more fuel. Assuming you're WB is reporting 12.5AFR through the rev range, richen it out 12.0 from 3,800-4,600 rpm then thin it back out to 12.5AFR through the rest of the range. Right at the top (6,100-XXXX) bring it to around 12.8 and bump the timing 1-2 degrees to make your top end hit a little harder. You can do this via your PE multiplier, because essentially with your air model correct, it is there to calibrate WOT fuel. You're not "raping" it.

[bluegoat06]

GTP, Don't worry about the meth, just clean the KR, and add 1-2 gallons of 100 octane to the tank if you don't have access to 93 octane. done.

Gn2beatu wrote it prefectly. Funny how your car is flying with less timing than stock top end. Like i always say in our local forum, is not how much more you can add, but how much less you should have to make this cars faster i haven't seeing the first one running at my track on the lean side to run faster. G8's like to be rich, once you find what she likes for fuel, going leaner won't give her more, you'll find some people who says 12.8-13.2 is the sweet spot, LOL, but down the track, on the contrary, go richer and watch your mph increase. and you can put you KR sensitivity back, she runs better with less timing, the fact that even KR is removing 2* and still trapping at 117 is telling you something. give her what she wants, is right there in the logs if you look at it vs your track slip

[IDRIVEAG8GT]

GTP, Don't worry about the meth, just clean the KR, and add 1-2 gallons of 100 octane to the tank if you don't have access to 93 octane. done.

Gn2beatu wrote it prefectly. Funny how your car is flying with less timing than stock top end. Like i always say in our local forum, is not how much more you can add, but how much less you should have to make this cars faster i haven't seeing the first one running at my track on the lean side to run faster. G8's like to be rich, once you find what she likes for fuel, going leaner won't give her more, you'll find some people who says 12.8-13.2 is the sweet spot, LOL, but down the track, on the contrary, go richer and watch your mph increase. and you can put you KR sensitivity back, she runs better with less timing, the fact that even KR is removing 2* and still trapping at 117 is telling you something. give her what she wants, is right there in the logs if you look at it vs your track slip

With his cam, given how our heads flow, I believe it'd benefit from running a tad leaner on the very top as opposed to richer. You need a faster flash to make power with the basically anything over 6,200 RPM.

Not contradicting you but in my N/A days, this is how I did it, and I busted off a 119 MPH trap speed with a cam even smaller than his.

The car is our puppet, as we are the puppeteers.

Not all puppeteers move their puppets in the same fashion.

[DSteck]

What's wrong with meth?



Oh. Nothing. Because its wonderful. I'd drink it if it wouldn't kill me.

[bluegoat06]

With his cam, given how our heads flow, I believe it'd benefit from running a tad leaner on the very top as opposed to richer. You need a faster flash to make power with the basically anything over 6,200 RPM.

Not contradicting you but in my N/A days, this is how I did it, and I busted off a 119 MPH trap speed with a cam even smaller than his.

The car is our puppet, as we are the puppeteers.

Not all puppeteers move their puppets in the same fashion.

Idrive, what do you mean a faster flash to make power with anything over 6200rpm ?

our cars react a little bit different around here, everyone insist at 12.8, or worst 13.0-13.2, this cars would see lots of KR in the summer with such afr's, and are only consistent on cold engines with one run every hour, i'm not saying you have a track queen, all cars are created differently, must be the gas or something, but whatever it is, same people would be stumped to see the improvements going richer.

I guess is always good to do a fueling window swipe, at the track, and go from rich to lean and see what she likes. Around here i could say the biggest portion of L76's seem to like the rich side, cam or not, some people don't believe it because there is no way an engine would make more power richer, you know given the dyno doesn't lie type of thing..... i'd say give it a try both ways, it's easier to error out on the rich side and lean her butt up to see how she does

[bluegoat06]

What's wrong with meth?



Oh. Nothing. Because its wonderful. I'd drink it if it wouldn't kill me.

Lol

[gtp6515]

From what I understand of w/m injection, it lowers the iat's approximately 30 degrees, and I would think all summer it would be a bonus. And as long you don't go balls out, it will not use it. WW fluid is fairly cheap. I just don't know how you would have timing pull out in the event of a failure. If I could get iat's in the 60's when it is 90 out, I would assume I would have additional power on tap. I have had such a difficult time understanding tuning, I almost feel like when I get new info, it just confuses me further. This just isn't clicking. I really want to learn this stuff, and not rely on others. I certainly appreciate your educated responses to these issues. I even struggle getting my ngk/afx to work properly. I wish it just read the right #'s for Lambda to start with. I bought this as DSTECK said this was best, and from what I have read...he knows his stuff!

[bluegoat06]

Tuning is easy once you grasp the basics, hang in there, it'll pay in the end. Do you know of a meth kit we can use without boost ? there was somebody in our forum saying he had it done, he said the manufacturer got it working based on MAF HZ or something like that, but i think he never posted the details where to get it i'll be all over that, especially since our highest octane gas is 91 octane around here. 100 octane gas is available, but only a few gas stations sell it, $10-$12 a gallon, Lol, and E85 gas stations are further away, i have to drive 50 miles to pump a full tank, and drive day and a half with it, not worth it for me.

[gtp6515]

Snow performance does maf for na cars.

[IDRIVEAG8GT]

Idrive, what do you mean a faster flash to make power with anything over 6200rpm ?

our cars react a little bit different around here, everyone insist at 12.8, or worst 13.0-13.2, this cars would see lots of KR in the summer with such afr's, and are only consistent on cold engines with one run every hour, i'm not saying you have a track queen, all cars are created differently, must be the gas or something, but whatever it is, same people would be stumped to see the improvements going richer.

I guess is always good to do a fueling window swipe, at the track, and go from rich to lean and see what she likes. Around here i could say the biggest portion of L76's seem to like the rich side, cam or not, some people don't believe it because there is no way an engine would make more power richer, you know given the dyno doesn't lie type of thing..... i'd say give it a try both ways, it's easier to error out on the rich side and lean her butt up to see how she does

Simple fundamentals of burn characteristics. The less fuel that is there, the faster a complete burn takes place

A rule of thumb goes, "run an engine richer at peak torque and leaner at peak power." It has served me well for awhile now.

In a way this is just like tuning a turbo car to get it to not nose over after the turbos run out of their efficiency range. Timing in, fuel out, because the engine is well past peak load conditions. Same thing applies. At about 6,200 peak power is either almost there or there, and it's going to fall off very quickly just like the torque curve. Lean it up and ramp the timing to it, to make power past where the cam falls off.

Meaning that when it shifts it should be right back in the middle of peak torque coming off and peak power coming on, which means it'll accelerate faster and lend better times.

Sure you can run one rich and it'll be fine though, and most people won't really notice a difference.

Consider this, there isn't a dyno around for 200 miles. Just a nice drag strip. I've tried it over and over again with fantastic results on a slew of different cars and seen a couple pick up over 4mph and 2/10's with nearly identical DA's.

Question lends though, is it safe? Not as much as running one rich and just enjoying the wonderful LS top end kick.

I will say this though, there are some certain applications that take kindly to more fuel as opposed to leaner, and those are typically applications that make peak power nearing 7,000 rpm. A bolt on LS7 I did with a mild cam liked 12.0 AFR across the rev range.

As you said, fuel plays into it as well. Our E10 here is only about 5% max ever, and is extremely clean. No hydrogen contamination anyways. And our Shell deals with 93 octane.

You're in Cali right? Nasty crap you guys have.

[gtp6515]

Does 92 vs 93 octane make a noticeable difference? I was running 92 at the time of this run, but iats were low. Knock would probably be worsenifnit was warm out.

[DSteck]

I run a MAF based controller on my meth kit, as does every turbo car I do with meth if I have a say in it. Alky Control has a MAF frequency converter box that you can get with the kit. It works perfectly fine.

You guys would probably flip if you saw how rich I run my car on 19psi... and according to the plugs, it loves it.

[IDRIVEAG8GT]

I run a MAF based controller on my meth kit, as does every turbo car I do with meth if I have a say in it. Alky Control has a MAF frequency converter box that you can get with the kit. It works perfectly fine.

You guys would probably flip if you saw how rich I run my car on 19psi... and according to the plugs, it loves it.

Hey I run 10.8 for my truck on meth with 21 pounds, plugs are light tan here

What AFR were you on when you made your 1,000WHP pull? I saw a little haze of smoke from the pipes.

[gtp6515]

When I called Alky, they recommended I call Snow for maf based meth system. Is it worth it on a car with my mods? And if so, what safety measures are there if somehow the meth doesnt fire?