How to stage an auto turbo car?
12-04-2016, 09:50 AM
#44
Holy thread revival...
Every combo is different, but I am on e85 and run 36° coming up on boost, and taper it out as boost builds.
I light the top bulb and inch in on the foot brake with about 3psi, and when I set the trans brake the holley knocks the timing back to 15° and this sends boost to 7psi in just over a second and I'm off.
This is a repeatable 1.30 60ft launch at my track.
Every combo is different, but I am on e85 and run 36° coming up on boost, and taper it out as boost builds.
I light the top bulb and inch in on the foot brake with about 3psi, and when I set the trans brake the holley knocks the timing back to 15° and this sends boost to 7psi in just over a second and I'm off.
This is a repeatable 1.30 60ft launch at my track.
12-05-2016, 05:25 AM
#45
TECH Enthusiast
For the car that I work on, (400", single 88 or 98 (dependent on class/rules) on Q16, we do the same thing.
Foot brake on the first two step then once the second bulb gets lit he goes on the brake, drops timing down to the preset and sets the launch boost to the set value. Pretty much exactly as Camarols1 explained it. It works. 1.10-1.20 60' depending on what we're setup to run (radials or a slick for low prep tracks)
Foot brake on the first two step then once the second bulb gets lit he goes on the brake, drops timing down to the preset and sets the launch boost to the set value. Pretty much exactly as Camarols1 explained it. It works. 1.10-1.20 60' depending on what we're setup to run (radials or a slick for low prep tracks)
12-06-2016, 07:34 PM
#46
i have na timing until around 5 to 6 psi
pull up to the first bulb and get on the brake and 2 step
with megasquirt i yank a ton of timing out on the 2 step and it helps get boost up quicker.
itll make 9-10 psi in less than a second
bump into the second bulb and when i release the brake the timing goes back up and then pulls it back down as it makes more boost.
ive been 1.22 60' on the back tires with a single adjustable shock and 275 pros
pull up to the first bulb and get on the brake and 2 step
with megasquirt i yank a ton of timing out on the 2 step and it helps get boost up quicker.
itll make 9-10 psi in less than a second
bump into the second bulb and when i release the brake the timing goes back up and then pulls it back down as it makes more boost.
ive been 1.22 60' on the back tires with a single adjustable shock and 275 pros
12-08-2016, 09:01 AM
#47
Ive heard some conflicting info in the past about this, so im gonna ask just to be clear.
In the manual cars, i have the timing go as far back as i can. Negative sometimes.
I hear with autos, you keep positive timing in it.
So lets so at 15psi, im at 15 degrees going down the track, so lets just say 7psi is 20 degrees (literally just making up numbers, not real world.)
Where do i want the timing with an auto car w/ t brake when on the 2 step?
You wouldnt ever run more timing on the 2 step then you would have in your timing map, correct?
In the manual cars, i have the timing go as far back as i can. Negative sometimes.
I hear with autos, you keep positive timing in it.
So lets so at 15psi, im at 15 degrees going down the track, so lets just say 7psi is 20 degrees (literally just making up numbers, not real world.)
Where do i want the timing with an auto car w/ t brake when on the 2 step?
You wouldnt ever run more timing on the 2 step then you would have in your timing map, correct?
12-08-2016, 09:33 AM
#48
TECH Fanatic
I would do the same thing when on the TB. Pull it back as much as you can. I can foot brake 8-10 psi around 2600rpm, commanding -20* on the 2 step.
12-08-2016, 10:39 AM
#50
Ive heard some conflicting info in the past about this, so im gonna ask just to be clear.
In the manual cars, i have the timing go as far back as i can. Negative sometimes.
I hear with autos, you keep positive timing in it.
So lets so at 15psi, im at 15 degrees going down the track, so lets just say 7psi is 20 degrees (literally just making up numbers, not real world.)
Where do i want the timing with an auto car w/ t brake when on the 2 step?
You wouldnt ever run more timing on the 2 step then you would have in your timing map, correct?
In the manual cars, i have the timing go as far back as i can. Negative sometimes.
I hear with autos, you keep positive timing in it.
So lets so at 15psi, im at 15 degrees going down the track, so lets just say 7psi is 20 degrees (literally just making up numbers, not real world.)
Where do i want the timing with an auto car w/ t brake when on the 2 step?
You wouldnt ever run more timing on the 2 step then you would have in your timing map, correct?
As far as specifics it really depends on RPM and what boost you want to leave on. I only pull the timing back enough so the boost level is reached quickly and the car leaves good transitioning off the two step. Normal sized turbos in the 76-88mm range can be spooled up quick without dropping timing to negative. On a 84mm manual car I only bring it down to ~13 degrees and can have 10lbs in a second on the two step, second his foot comes off the clutch its ramping in more timing and more boost. On an auto car I can have ~20 degrees in it leaving off the TB at the same boost as the manual car but instead of ramping in timing I'm ramping in boost, if that helps explain it?
12-08-2016, 10:47 AM
#51
Ok, so basically you run as much timing as you can to achieve the boost you need, lowering it to gain boost/time, but never run MORE timing then whats in the map.
Basically saying, if you run 20degrees going down the track, you will try 20 degrees on the 2 step. If its lazy or doesnt build enough boost, lower it 15, then maybe 10, until the amount of time/boost is acceptable.
Basically saying, if you run 20degrees going down the track, you will try 20 degrees on the 2 step. If its lazy or doesnt build enough boost, lower it 15, then maybe 10, until the amount of time/boost is acceptable.
12-08-2016, 11:11 AM
#52
Ok, so basically you run as much timing as you can to achieve the boost you need, lowering it to gain boost/time, but never run MORE timing then whats in the map.
Basically saying, if you run 20degrees going down the track, you will try 20 degrees on the 2 step. If its lazy or doesnt build enough boost, lower it 15, then maybe 10, until the amount of time/boost is acceptable.
Basically saying, if you run 20degrees going down the track, you will try 20 degrees on the 2 step. If its lazy or doesnt build enough boost, lower it 15, then maybe 10, until the amount of time/boost is acceptable.
Not only timing but mess with A/F as well... I see some guys run it so fat that as soon as it touches boost that its drowning in fuel. Let the turbo get going and build 5-7lbs before you start pulling too much out of it or adding much fuel. Once it comes on then it should come on quick and you can make the necessary changes from there.
