224 Stage I Single Turbo Buick V6 does the impossible. 8.76 @ 158.7

[HighPSI]

When you select "View" under the Boost setting of the controller, does the controller display the curve you are asking for under the Boost settings or is it diferent then you are asking for? My concern was: based on the ramps, targets, and timers that your boost curve wasn't possible.

Let me explain how the controller works. If your ramps are too shallow you will never reach your target boost before the next stage timer starts.
Here's an example of an incorrect boost curve. Say you are at 10 psi in the first stage and the second stage you are targeting 30 psi and using a ramp of 5. This would take 4 seconds for the controller to reach the target (30-20)/5=4. If you were to have the third stage coming in 2 seconds after the 2nd, then you won't ever reach the 2nd target before the 3rd stage kicks in. Since the ramp is too shallow, the controller only reaches 20psi (instead of the targeted 30). All of this can be seen in the VIEW screen of the controller.

 

[jimmymorrisonjr]

Cal, I am always in the habit of making sure that my target boost is set to what the stage time and ramp will allow by checking the graph while adjusting target psi. It just seems easier that way. I was under the impression although that if you set the target psi higher than the ramp or stage time together allow that there is a sudden jump to the target psi between stages. Am I correct in that?

 

[HighPSI]

The CO2 can't just "jump" to the target. The timer has priority, so if it doesn't reach the target, it will just go from the boost point it can reach and then apply the next ramp and attempt to reach the next target. On some strategies like DonWG's, the controller is being asked to raise the boost in some stages and lower it in others.

 

[Chevota]

Got your hands on a AMS2000 yet Cal? If so, like it?

 

[Alky V6]

When you select "View" under the Boost setting of the controller, does the controller display the curve you are asking for under the Boost settings or is it diferent then you are asking for? My concern was: based on the ramps, targets, and timers that your boost curve wasn't possible.

Let me explain how the controller works. If your ramps are too shallow you will never reach your target boost before the next stage timer starts.
Here's an example of an incorrect boost curve. Say you are at 10 psi in the first stage and the second stage you are targeting 30 psi and using a ramp of 5. This would take 4 seconds for the controller to reach the target (30-20)/5=4. If you were to have the third stage coming in 2 seconds after the 2nd, then you won't ever reach the 2nd target before the 3rd stage kicks in. Since the ramp is too shallow, the controller only reaches 20psi (instead of the targeted 30). All of this can be seen in the VIEW screen of the controller.

Yes, I understand that. I go back and forth from the view screen to settings table constantly. I've heard there is new software that makes it easier to adjust the curve without the back and forth. I've just learned to deal with this old software and haven't found it absolutely necessary to send the box back for the upgrade. But yes, I'm well aware of the VIEW feature. I follow up each change in the settings table with the VIEW screen.
I have to tell you, the data capture of the control pressure curve is not far off from what it looks like in the view screen. That's why I told you that I too don't see much reason to the settings, yet the curve that it produces is actually pretty nice. That's why I also told you that you need to plug the numbers into a unit and check it out for yourself, when you get a chance.

 

[Alky V6]

The CO2 can't just "jump" to the target. The timer has priority, so if it doesn't reach the target, it will just go from the boost point it can reach and then apply the next ramp and attempt to reach the next target. On some strategies like DonWG's, the controller is being asked to raise the boost in some stages and lower it in others.

Yes. This is what I have found.

 

[Alky V6]

The AMS2000 sounds interesting from what I've read, but as long as the 1000 doesn't limit me, I'm going to stick with it. Like I've stated before, I don't have the resources to go out and grab up every new electronic gadget that hits the market.

 

[Alky V6]

A question for Dusty, since we seem to be covering almost every major technical area with this thread.
Dusty. From the standpoint of consistency, such as for bracket racing, which is more preferred? A loose or tight TC?

 

[Dusty Bradford]

A question for Dusty, since we seem to be covering almost every major technical area with this thread.
Dusty. From the standpoint of consistency, such as for bracket racing, which is more preferred? A loose or tight TC?

For bracket racing I'd prefer it on the looser side. Helps to stage the car and is easier on traction from track to track.

Of course if I was trying to bracket race a turbo car I'd be backing it way down to much slower 60' times so the launch would be consistent.

 

[Alky V6]

Thanks for confirming that. I recently learned from a bracket racing guru that a loose converter is preferred to a tight one for consistency reasons.

 

[S2V6RACER]

The AMS2000 sounds interesting from what I've read, but as long as the 1000 doesn't limit me, I'm going to stick with it. Like I've stated before, I don't have the resources to go out and grab up every new electronic gadget that hits the market.

I'll let you know in a month or so how the 2000 looks. It's looking like it is going to be real nice. From some things I have read there is a strategy to control a target boost (manifold) unlike the 1000 can so I think it's going to save a little guess work.

 

[Alky V6]

I'll let you know in a month or so how the 2000 looks. It's looking like it is going to be real nice. From some things I have read there is a strategy to control a target boost (manifold) unlike the 1000 can so I think it's going to save a little guess work.

That would certainly make the unit more user friendly. From what I understand, the 2000 will have a much better user interface where it comes to being able to quickly come up with a boost curve, but the 1000 will still be able to come up with any sort of boost curve that the 2000 can come up with. It will just be more work with the 1000 to figure out the settings that will give you the desired boost curve. If someone is already used to dealing with the 1000 to come up with complex boost curves, then switching to the 2000 would not result in a performance advantage. Just easier to make changes.
Although, I have to say that the controller settings that I'm presently using can be changed easily to come up with some pretty strange curves, if they were needed. That's mainly why I have all six stages being used. Even though now, the target control curve could be made with less stages, the timer points for the stages are set at strategic spots so that if there is a traction problem in a certain part of the run, I can quickly adjust the control curve to battle the problem without having to start adding stages in and having to figure out the timer issues. With the stages already present and the timer settings for those stages roughly set already, it makes for slighty quicker changes when a traction problem comes up. A problem with a different track and/or condition is a good example.
Like what happened to me at Firebird. The controller changes I had to make at that event went smooth and quick. It would have been a different story if I had to start adding stages in and figure out the correct timer settings.

 

[Alky V6]

Back to converters. Does anyone know what the flash stall rpm breakpoint is in determining whether a TC is tight or loose in terms of picking a flash stall speed for bracket racing and mainly, consistency reasons?

 

[tom j]

Don - Cal - Dusty,
I have a somewhat comparable combination as you Don. Its a large turbo 88m with a tight converter and NOS used to spool. It has little track time and tuning, but has turned a good number at low boost and an easy 60ft. I could post a XFI data log for comparison to learn from.

 

[Alky V6]

Don - Cal - Dusty,
I have a somewhat comparable combination as you Don. Its a large turbo 88m with a tight converter and NOS used to spool. It has little track time and tuning, but has turned a good number at low boost and an easy 60ft. I could post a XFI data log for comparison to learn from.

I think that would be very nice. Please do.

 

[HighPSI]

Yes, I understand that. I go back and forth from the view screen to settings table constantly. I've heard there is new software that makes it easier to adjust the curve without the back and forth. I've just learned to deal with this old software and haven't found it absolutely necessary to send the box back for the upgrade. But yes, I'm well aware of the VIEW feature. I follow up each change in the settings table with the VIEW screen.

If you do this, then you already know if your target boost settings were possible, which was all I was asking from the beginning. Looking at your 3rd and 4th stages I wasn't sure it was possible to reach the traget settings. Once again, I was not talking about your car or the mechanical ability for the CO2 to reach a traget which you keep coming back to, I was talking about the strategy itself.

Got your hands on a AMS2000 yet Cal? If so, like it?

I haven't played with the 2000 on an actual car, but so far can't see any reason to swap from a 1000 to a 2000. I personally would not like to target actual boost numbers, to me they are just that, "numbers". The 2000 may be the exception, but every other system that I have seen using this method tends to overshoot the boost. The Innovate tried to cure this by adding additional curves to their ramps. By programing CO2 values, you can get an inclination of how hard the turbo is working which helps with guys who aren't logging backpressure. The 2000 does have some additional datalogging stuff which would be good for those with inferior engine management systems.
I may change my opinion Thursday. I intend to talk with Sebastian about this and other things.

 

[tom j]

Here is a log of the only 1/4 mile pass. It stalled at 3200@0psi and did a 1.44 60ft. The launch was set @ 8psi on the boost controller. The NOS shuts off @ 149kpa.

 

[Dusty Bradford]

Thanks for confirming that. I recently learned from a bracket racing guru that a loose converter is preferred to a tight one for consistency reasons.

They also prefer 15x33 tires with 600hp:biggrin:

 

[Dusty Bradford]

Back to converters. Does anyone know what the flash stall rpm breakpoint is in determining whether a TC is tight or loose in terms of picking a flash stall speed for bracket racing and mainly, consistency reasons?

There really is no breakpoint. Obviously you want it loose enough to make staging the car as easy as possible without burning the fluid.

As far as track conditions. I had a really loose converter for the smallblock combo that I used in Reynolds a couple years ago. It only dropped 400 on the gear change but would 60' in the 1.34 range and the car would still run 5.0's. I could make 6-7 passes on it before the fluid needed to be changed.

 

[Alky V6]

They also prefer 15x33 tires with 600hp:biggrin:

Correct me if I'm wrong, but in a bracket situation, I would imagine they're not staging at the line at full stall, but rather on the 2-step at a lower rpm. Along with a high stall TC, this would cause the hit to be softer on transbrake release.
You are right about the tires. Bracket racers like the big rubber.