I finally got anti lag to work!
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That's not how I would do it.
This is how I do it. I leave the main timing table alone and set it up for advanced timing on the footbrake to get boost built and then the timing I want down track under boost.
How I retard the timing on the transbrake to get more boost built after I've built 7-8psi like we're talking about here in this thread is with the AFR spark correction table.
This table references the commanded fuel multiplier currently commanded, and when that multiplier is commanded( I.E. a 1.0 fuel multiplier with a 14.7 Stoich would command 14.7 if your VE table is correct) it either adds or retards the timing value that you've inputted. This table works off RPM and the commanded fuel multiplier. SO to pull the timing out you want, what you would do is reference the fuel multiplier coefficient that you're commanding on the transbrake at 7-8psi at 4000rpm in the AFR spark correction table and input -10 in those tables. This will only allow it to retard the timing at that certain instance and no where else. That way you're not rolling down the highway and hit it WOT and end up pulling timing out where you need it most to get the turbo's lit and you don't have to constantly swap tunes because you've messed with your main timing table.
You can also use this table for adding timing in rpm regions that you know your car is slower to spool in while moving. Such as a M6 car that needs some help from 2000rpm-4000rpm in getting it's turbo(s) to spool. You can leave your main timing table alone and add in 4-16 degrees(using these values as an example) of timing in that 2000-4000rpm region while commanding whatever fuel multiplier you're commanding and add timing there so that the turbo's spool quicker and you get better transient response.
This is especially helpful for big single turbo M6 and automatic cars that roll race a lot on the highway and need boost to come in as fast as possible from the hit.
This is how I do it. I leave the main timing table alone and set it up for advanced timing on the footbrake to get boost built and then the timing I want down track under boost.
How I retard the timing on the transbrake to get more boost built after I've built 7-8psi like we're talking about here in this thread is with the AFR spark correction table.
This table references the commanded fuel multiplier currently commanded, and when that multiplier is commanded( I.E. a 1.0 fuel multiplier with a 14.7 Stoich would command 14.7 if your VE table is correct) it either adds or retards the timing value that you've inputted. This table works off RPM and the commanded fuel multiplier. SO to pull the timing out you want, what you would do is reference the fuel multiplier coefficient that you're commanding on the transbrake at 7-8psi at 4000rpm in the AFR spark correction table and input -10 in those tables. This will only allow it to retard the timing at that certain instance and no where else. That way you're not rolling down the highway and hit it WOT and end up pulling timing out where you need it most to get the turbo's lit and you don't have to constantly swap tunes because you've messed with your main timing table.
You can also use this table for adding timing in rpm regions that you know your car is slower to spool in while moving. Such as a M6 car that needs some help from 2000rpm-4000rpm in getting it's turbo(s) to spool. You can leave your main timing table alone and add in 4-16 degrees(using these values as an example) of timing in that 2000-4000rpm region while commanding whatever fuel multiplier you're commanding and add timing there so that the turbo's spool quicker and you get better transient response.
This is especially helpful for big single turbo M6 and automatic cars that roll race a lot on the highway and need boost to come in as fast as possible from the hit.
The way you're able to manipulate timing with that table is much better for your tune overall.
Instead of having to ramp the timing back up after 4000rpm, the back down again, you can build your own curve in the main table and then have the adder table subtract or add timing as the tune-up calls for it.
It's your car though, thought I'd help.
Instead of having to ramp the timing back up after 4000rpm, the back down again, you can build your own curve in the main table and then have the adder table subtract or add timing as the tune-up calls for it.
It's your car though, thought I'd help.
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The way you're able to manipulate timing with that table is much better for your tune overall.
Instead of having to ramp the timing back up after 4000rpm, the back down again, you can build your own curve in the main table and then have the adder table subtract or add timing as the tune-up calls for it.
It's your car though, thought I'd help.
Instead of having to ramp the timing back up after 4000rpm, the back down again, you can build your own curve in the main table and then have the adder table subtract or add timing as the tune-up calls for it.
It's your car though, thought I'd help.
I did this same thing with my old turbo car for the longest time. I too found the same issue that just adding timing, it would build 7-8psi very quickly on the footbrake, but it would flat line and wouldn't build anymore even after I grabbed the transbrake in the second beam at the track before the lights dropped.
I started talking to some of the guys in the 275 classes that ran turbo's and they all recommended once I got that 7-8psi of boost built to yank 8-12 degrees of timing out of it only after I had that 7-8psi of boost built. If I tried yanking that 8-12 degrees out before I had that 7-8psi built it wouldn't do anything and actually wouldn't even build anymore boost than it already had if I was below 7-8psi.
The first time I did this and pulled 8 degrees at 8psi it started popping and banging like it NEVER did before and I had 15psi of boost built from 8 within 1 second. It was like a totally different car the way it launched. I've recommended this method to everyone who has ever asked me about how to build boost and it's worked the exact same way for them every time.
I started talking to some of the guys in the 275 classes that ran turbo's and they all recommended once I got that 7-8psi of boost built to yank 8-12 degrees of timing out of it only after I had that 7-8psi of boost built. If I tried yanking that 8-12 degrees out before I had that 7-8psi built it wouldn't do anything and actually wouldn't even build anymore boost than it already had if I was below 7-8psi.
The first time I did this and pulled 8 degrees at 8psi it started popping and banging like it NEVER did before and I had 15psi of boost built from 8 within 1 second. It was like a totally different car the way it launched. I've recommended this method to everyone who has ever asked me about how to build boost and it's worked the exact same way for them every time.
Then at different RPM intervals down track, or on the transbrake needing more boost or even rolling down the highway doing roll races you can advance or retard however much extra timing you need to get the job done all without having to even touch your main timing table that you've set-up for the curve you and your car want. Heck you could even use it like a step retard if you needed to for added traction or as a launch retard, but instead of a 12v trigger that cuts the retard on, you're using a fuel multiplier coefficient and engine RPM.
I would use it on the trans brake for added boost and then I'd also use it from 2500-4500rpm while rolling down the road at speed in any gear to really get boost in quickly. It made a WORLD of difference on my old turbo car and I will be utilizing it again on my new set-up.
This is why I tell guys all the time that are intimidated by larger turbo's and turbine wheels that lag can be completely eliminated by the right cam, the right converter, the right rear gear and a great tune with a few little tricks.
I spent 7 hours today playing with the main timing table and leaning out the fuel values. Finally paid off. Here is the video. I was able to get 10lbs off footbrake only also. Personally, I would rather just swap the tunes. It takes all of 2 minutes.
http://www.youtube.com/watch?v=i9Wmty7C8Oo
http://www.youtube.com/watch?v=i9Wmty7C8Oo
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As was mentioned, I pulled timing -10 degrees in the cells just above and below the point that I was able to hit 7lbs of boost. I did this from 3600-4000 rmps then ramped it back up until about 4600 rpms and then started pulling timing again.
Today the weather was nicer and got to do some tuning driving. My vic Jr. and tall elbow ran a little rich so I pulled some fuel. Good thing I got to drive it today. I am not sure why but the Pro Flo intake ran a whole lot leaner. So I added the fuel back in. I finally got it to be in the 11.5 AFR range, but again this was on the street.
Tomorrow is the first day the track is open. It is really green and the owner asked me today to only run to the 330ft. He said I make stupid power and is worried with the temps only being in the 40's. I said I would. We will see. lol Sunday the weather is supposed to be 55 degrees though.
I will post some time slips and videos if I can. I am going by myself but will try to get some one to take a video. I will also try and post my logs from the runs and the changes I made if I can.
Almost forgot. With my new PG and after messing with the fuel, I tried a pass on the street footbraking. Left at 7lbs and destroyed the tires until I hit the 7k rev limiter. I think it should get the wheelies back tomorrow.
Today the weather was nicer and got to do some tuning driving. My vic Jr. and tall elbow ran a little rich so I pulled some fuel. Good thing I got to drive it today. I am not sure why but the Pro Flo intake ran a whole lot leaner. So I added the fuel back in. I finally got it to be in the 11.5 AFR range, but again this was on the street.
Tomorrow is the first day the track is open. It is really green and the owner asked me today to only run to the 330ft. He said I make stupid power and is worried with the temps only being in the 40's. I said I would. We will see. lol Sunday the weather is supposed to be 55 degrees though.
I will post some time slips and videos if I can. I am going by myself but will try to get some one to take a video. I will also try and post my logs from the runs and the changes I made if I can.
Almost forgot. With my new PG and after messing with the fuel, I tried a pass on the street footbraking. Left at 7lbs and destroyed the tires until I hit the 7k rev limiter. I think it should get the wheelies back tomorrow.
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I am pulling -10 degrees from the main spark timing (high octane) table. What I did was data logged building boost on the transbrake. Then I pullled the histogram from that log. Going through the log I tried to find the point where my 2 step kicks in and 7lbs of boost intersect. The problem is on the histogram it isn't in KPA in it is grams per cylinder or something like that. Next I went into my tune and at that same point on my main timing table I -10 timing. I was in the mid 20's at that point normally and now am around 12-14. I did this for the cell above and below that intersection point since you can't 100 percent pin point where they intersect. At least I can't. lol
I then pulled a little bit of fuel in that region aslo. I did a little at a time and made a pull about every hour for 7 straight hours until it got worse. Then I went back to my previous mark. I hope I explained that better.
Let me see if it works today and I will post a picture of those two screen shots so others can see what I did.
I then pulled a little bit of fuel in that region aslo. I did a little at a time and made a pull about every hour for 7 straight hours until it got worse. Then I went back to my previous mark. I hope I explained that better.
Let me see if it works today and I will post a picture of those two screen shots so others can see what I did.
Good luck at the track and be safe. Maybe I missed it but what is the button doing? Is that the IAT trick to reference IAT table timing? I also have another timing trick if anyone is interested, it basically references the idle timing cells while you're not moving. As soon as you move, it switches back to the main spark tables 
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All this talk about pulling timing and trickery......all I did was have my car tuned at speed inc like any ole car and through a msd 2 step on there anything 3k rpm and up it would build full boost 10# within about 4 seconds.
6 speed, stock ls1, 238/240 .605/.605 112 cam, rear mounted 7686 t6 .96 a/r large frame garrett, 2.5in. Pipes y'd into a single 3in. All wrapped and painted.
6 speed, stock ls1, 238/240 .605/.605 112 cam, rear mounted 7686 t6 .96 a/r large frame garrett, 2.5in. Pipes y'd into a single 3in. All wrapped and painted.
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Good luck at the track and be safe. Maybe I missed it but what is the button doing? Is that the IAT trick to reference IAT table timing? I also have another timing trick if anyone is interested, it basically references the idle timing cells while you're not moving. As soon as you move, it switches back to the main spark tables
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Well, everything went well today. I got a video of the last pass. It was leaving at 10lbs and running 10lbs. My first time with the PG and it launched well for what I tried. We tried to launch at 14lbs but it just blew the tires off. As you can see from the video the track was stupid slick. It was only 38 degrees. Some of the 5 sec cars only ran 7's, no traction. Tomorrow it is supposed to be 55. I am going to put my 28" slicks on and turn up the boost.
I logged all my passes. I only shifted at 6300rpms which is way too low. Took some getting used to after haveing a TH400. Also, I need some help. I had some areas that had a KR of 3.9 I was told that was too high. What do I need to do to drop that down? Just add some more fuel? Timing was not high in that area. Timing is still 13-14 degrees. Tried to run higher but I was worried about the KR so I didn't mess with it.
I love this Pro Flo and new PG. I think sub 5's are in the bag. Drove 40 miles, made 5 passes and drove home on my Drag radials. I can post my log if someone wants to look at it. I don't want to change anything except to fix the KR.
I logged all my passes. I only shifted at 6300rpms which is way too low. Took some getting used to after haveing a TH400. Also, I need some help. I had some areas that had a KR of 3.9 I was told that was too high. What do I need to do to drop that down? Just add some more fuel? Timing was not high in that area. Timing is still 13-14 degrees. Tried to run higher but I was worried about the KR so I didn't mess with it.
I love this Pro Flo and new PG. I think sub 5's are in the bag. Drove 40 miles, made 5 passes and drove home on my Drag radials. I can post my log if someone wants to look at it. I don't want to change anything except to fix the KR.
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Good luck at the track and be safe. Maybe I missed it but what is the button doing? Is that the IAT trick to reference IAT table timing? I also have another timing trick if anyone is interested, it basically references the idle timing cells while you're not moving. As soon as you move, it switches back to the main spark tables
9 Second Club
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From: Norn Iron
Here is my car playing around with the anti-lag. It it set to retard 10 degrees of timing at 2700 rpm and to cut ignition at 2950. I am still not building what I consider to be enough, or fast enough. Matt was able to build right up to 14 much quicker than I am. I am scratching my head a bit on this one.....
http://www.youtube.com/watch?v=2SIHY...ature=youtu.be
http://www.youtube.com/watch?v=2SIHY...ature=youtu.be
Here is my car playing around with the anti-lag. It it set to retard 10 degrees of timing at 2700 rpm and to cut ignition at 2950. I am still not building what I consider to be enough, or fast enough. Matt was able to build right up to 14 much quicker than I am. I am scratching my head a bit on this one.....
http://www.youtube.com/watch?v=2SIHY...ature=youtu.be
http://www.youtube.com/watch?v=2SIHY...ature=youtu.be