Advancement of fuel delivery?

[Alky V6]

Hmm. I've definately seen these before

It looks like your typical high stall/high tq multiplying stator, common with many suppliers.

Fingers are crossed. Hoping it works as advertised.

 

[aminga]

I don't have a passenger seat, but if you stradle the nitrous bottle and wrap your arms around the crossbar behind the seat, that could work.

That would be one heck of a ride.

I'd do it Just borrow a saddle from charlie for the Nawz bottle.

 

[Dusty Bradford]

Dusty. On the PTC converters you sell, the 9.5 n/l I believe, is that a positive or negative rake on the primary pump?

Positive.

 

[Dusty Bradford]

Maybe I can get some of you large single turbo guys out there to participate in a simple comparison. This is something I've been wondering about for some time now. A lot of you have the 'perfect' combination, but from some of the videos I've seen, you're sitting at the starting line well after the light has turned green, still spooling your turbo up. What's up with that? You're lucky it's a 3 amber tree. That's great for a pretty timeslip, but how do you win races like that?

Comparison test:
Pull your car into the staging lights.
Bring the rpm up to 2400 rpm only, on the transbrake or foot brake.
On the amber before the green, go to WOT and release the brake. You must do this last step correctly for the comparison to be meaningful.
Let's limit boost to 27 psi.

Nothing can be done to help pre-spool the turbo before the release of the brake, besides bringing the rpm up to 2400. After the release of the brake, anything goes.

Better yet. Do this comparison test on a .500 pro light.

Post your timeslips, with incrementals. Or not,... and live the rest of your life in shame. :biggrin:

The only time I see this is in qualifying when emphasis is on e.t, not reaction time.

As for the comparison, really no sense in it. The TSO cars cut good lights when they need to. You won't see them going in at 2400 rpm, more like 3000+. This is the challenge in staging a turbo V6 with a large single.

No offense meant here, just being honest. Anyone can put n2o on a car and get it on boost immediately. When racing heads-up where n2o isn't allowed as a 2nd power adder, it's much more of a challenge to get the car to launch and cut a light. So, combination is everything. Engine, turbo, cam compression, converter.......everything has to work together. You have to be able to get the car on launch rpm and boost ASAP yet make enough power to run the #.

 

[Alky V6]

The only time I see this is in qualifying when emphasis is on e.t, not reaction time.

As for the comparison, really no sense in it. The TSO cars cut good lights when they need to. You won't see them going in at 2400 rpm, more like 3000+. This is the challenge in staging a turbo V6 with a large single.

No offense meant here, just being honest. Anyone can put n2o on a car and get it on boost immediately. When racing heads-up where n2o isn't allowed as a 2nd power adder, it's much more of a challenge to get the car to launch and cut a light. So, combination is everything. Engine, turbo, cam compression, converter.......everything has to work together. You have to be able to get the car on launch rpm and boost ASAP yet make enough power to run the #.

No offense taken. I'm just curious.
A car setup with a tight torque converter and one with a looser converter starting out at an identical low rpm. One having the advantage of nitrous assist with an oversized turbo, and the other having the advantage of getting in the powerband and possibly getting on a more appropriately sized turbo quicker. I just thought it would be interesting. By all rights, the nitrous assist really shouldn't be an advantage at all. Right?

 

[Alky V6]

Positive.

Hmmm. 9.5 and positive. If this stator doesn't do it, I may have to try one out.
Do you have a picture of the pump showing the amount of positive angle? Don't need an inside pic. Outside is fine.

 

[Dusty Bradford]

Hard to say.

Just from being at the track all the time and seeing different combos. I have seen both cars be able to cut great lights leaving on a pro-tree. I don't know that one has advantage over the other. But the n2o car will not have to build an overall matching combination because he has the n2o to fall back on.

The converter design has a huge role though. When you say tight, there are 2 versions of tight. Down low and up top.

Take a 10" n2o converter. It will be harder to spool than my 9.5 but will drop less rpm up top. So, they are tighter down low, looser up top. These make great converters for large turbo engines that don't need alot of help down low. From the NC's that have been traded in or sent in for a restall, most of his converters are exactly like this. Which is why small engine cars have a hard time spooling large turbo's. They seem to work great in a V6 car with a 70mm or smaller because you don't need a lot of low rpm stall.

 

[Dusty Bradford]

Hmmm. 9.5 and positive. If this stator doesn't do it, I may have to try one out.
Do you have a picture of the pump showing the amount of positive angle? Don't need an inside pic. Outside is fine.

I don't have any pics. I'll just say......much more positive than you have If yours is even positive at all.

Knowing what stator you had, I can figure out about what pump it would need to achieve the stall. I prefer a vastly different way of doing things which I feel is a necessity for the small motors.

 

[Alky V6]

Hard to say.

Just from being at the track all the time and seeing different combos. I have seen both cars be able to cut great lights leaving on a pro-tree. I don't know that one has advantage over the other. But the n2o car will not have to build an overall matching combination because he has the n2o to fall back on.

The converter design has a huge role though. When you say tight, there are 2 versions of tight. Down low and up top.

Take a 10" n2o converter. It will be harder to spool than my 9.5 but will drop less rpm up top. So, they are tighter down low, looser up top. These make great converters for large turbo engines that don't need alot of help down low. From the NC's that have been traded in or sent in for a restall, most of his converters are exactly like this. Which is why small engine cars have a hard time spooling large turbo's. They seem to work great in a V6 car with a 70mm or smaller because you don't need a lot of low rpm stall.

That's exactly why I thought it would be interesting to do that comparison. Speculation is one thing, but real world is much more interesting.

 

[Alky V6]

I don't have any pics. I'll just say......much more positive than you have If yours is even positive at all.

Knowing what stator you had, I can figure out about what pump it would need to achieve the stall. I prefer a vastly different way of doing things which I feel is a necessity for the small motors.

(Ooops)

 

[Alky V6]

I don't have any pics. I'll just say......much more positive than you have If yours is even positive at all.

Knowing what stator you had, I can figure out about what pump it would need to achieve the stall. I prefer a vastly different way of doing things which I feel is a necessity for the small motors.

My N/C is 10 degrees negative. I was suspecting that the 9.5 would need to be positive to make the size up and be as efficient on the top end as advertised.

 

[charlief1]

I'd do it Just borrow a saddle from charlie for the Nawz bottle.

I've got three here you can borrow Al.:biggrin: Now getting it out to Donnie along with you may be a chalenge but I think I can do it if you want. Just remember to wear diapers.:tongue:

 

[Alky V6]

I've recently come across some info that somewhat confirms my suspicions of the chilling effect that nitrous/methanol mixtures have on the combustion process. When shot levels get past a certain point, there can be enough cooling from the large amounts of methanol and nitrous oxide that is vaporizing and disassociating (heat of vaporization affect) during the compression stroke, that it cools down the heating of the mixture enough to retard some of the mixture from vaporizing and disassociating.
The mixture quenches or retards the heat build up during normal compression of the mixture and during combustion. Heat that is necessary to disassociate the molecules of the nitrous oxide and methanol for proper and complete combustion.

Factors that would have an affect on just how much power could be extracted from a large nitrous/methanol mix are:

Static compression ratio
Richness of the mixture
Temperature of the engine (cooling system)
Use of heat barrier coatings
Ignition timing
Preheat levels of the intake system, fueling system and plumbing
Preheat levles of the combustion chamber, cylinder, piston
Cylinder material
Intake air temperature

With large hits, anything that will contribute to preheating the mixture and keeping as much heat as possible in the cylinder and not absorbed into the cylinder wall, cylinder head, pistion, etc., would be helpful in vaporizing the intake charge.

Higher static compression ratios would help build up more heat from compression to vaporize more of the mixture before ignition.

A leaner mixture would cause more heat during the combustion process.
This one is tricky. Get too lean, and detonation becomes a problem. I have found this one out first hand. The tuning range where the lean mixture is helpful and detonation becomes a problem is very, very narrow. I would say within 5%.

Later ignition timing would allow more time for more of the mixture to vaporize during the compression stroke before ignition.

Heat barrier coatings would keep more heat inside the cylinder, preventing the cylinder head, cylinder wall and piston from helping to quench the mixture.

Allowing the intake to heat soak from engine heat would help preheat the charge to provide more complete vaporization.

 

[Alky V6]

So when my wide band is flat lining at 14.64:1 during certain tuneups with the nitrous, what do you think is happening?

I'll offer my opinion. I think a lot of the mix is going through the cylinder unburned. That is pretty well evidenced by a lack of power. I'd expect much more from a 300hp hit.
The mixture finishes vaporizing/disassociating in the exhaust system and ignites. That would explain the perfect burn detected by the wide band.

Rich methanol mixtures burn slow. So it wouldn't require much ignition retard to insure that any residual mix lit off in the exhaust system. This explains why the richer the total mix, the more chance of seeing the perfect burn reading on the wide band.

Could the ignition retard be further retarded to vaporize more of the mix through the compression stroke and have a larger amount of the mix work in the cylinder?

What is the better ratio of burn in the cylinder versus burn in the exhaust system? Having more burn in the cylinder means more pressure acting directly on the piston. Yet, having more mix burn in the exhaust system may help spool the turbo quicker.

 

[Alky V6]

Since we suspect a burn occurring in the exhaust system, what if we added a seventh nitrous injection nozzle before the turbine housing?

 

[aminga]

Since we suspect a burn occurring in the exhaust system, what if we added a seventh nitrous injection nozzle before the turbine housing?

Afterburners for a TR.

I was going to say add a couple of EGT probes at various lengths down the exhaust system.

 

[TurboTR]

With so many pages here I apologize if you have already done so, but the first thing that enters my mind is to remove the intercooler. With what you are doing, I'd guess it could pick up quite a bit from doing so.

Edit- and let the MAP go up along with that, to keep the air density up.

TurboTR

 

[charlief1]

So when my wide band is flat lining at 14.64:1 during certain tuneups with the nitrous, what do you think is happening?

I'll offer my opinion. I think a lot of the mix is going through the cylinder unburned. That is pretty well evidenced by a lack of power. I'd expect much more from a 300hp hit.
The mixture finishes vaporizing/disassociating in the exhaust system and ignites. That would explain the perfect burn detected by the wide band.

Rich methanol mixtures burn slow. So it wouldn't require much ignition retard to insure that any residual mix lit off in the exhaust system. This explains why the richer the total mix, the more chance of seeing the perfect burn reading on the wide band.

Could the ignition retard be further retarded to vaporize more of the mix through the compression stroke and have a larger amount of the mix work in the cylinder?

What is the better ratio of burn in the cylinder versus burn in the exhaust system? Having more burn in the cylinder means more pressure acting directly on the piston. Yet, having more mix burn in the exhaust system may help spool the turbo quicker.

Afterburners for a TR.

I was going to say add a couple of EGT probes at various lengths down the exhaust system.[/QUOTE]

After reading what you were talking about with the mix Donnie I think Al may have come up with an idea for you to look into. One other thing you might try may sound silly but I've noticed that you turn the engine off while staging. You might try letting it run a little longer which will heat it up some and that may give you enough heat in the engine to allow for better heating of the mixture. I know your engine runs fairly cool with the nitrous and the alky but I think with the added heat you'll get more power and less headaches.

 

[aminga]

Afterburners for a TR.

I was going to say add a couple of EGT probes at various lengths down the exhaust system.[/QUOTE]

After reading what you were talking about with the mix Donnie I think Al may have come up with an idea for you to look into. One other thing you might try may sound silly but I've noticed that you turn the engine off while staging. You might try letting it run a little longer which will heat it up some and that may give you enough heat in the engine to allow for better heating of the mixture. I know your engine runs fairly cool with the nitrous and the alky but I think with the added heat you'll get more power and less headaches.

Yea I was thinking that if it were burning in the exhaust the EGT's would get hotter for while as you get further from the head.

If it isn't burning fuel in the exhaust it the closest to the head will be the hottest.

 

[Alky V6]

With so many pages here I apologize if you have already done so, but the first thing that enters my mind is to remove the intercooler. With what you are doing, I'd guess it could pick up quite a bit from doing so.

Edit- and let the MAP go up along with that, to keep the air density up.

TurboTR

The IAT starts at 37C and ends at 75C in the 1/4 mi, measured 15" before the throttle body. This was on a 101F day.
I run ambient temp water in the intercooler. Basically, it acts as a large heat sink. It delays IAT rise. It does not cool the air below ambient temp. I do not ice the intercooler water.

I realize the idea is to heat the engine to better vaporize the nitrous/methanol mix.
My current tuneup allows me to heat the engine to 180 degrees by the time I stage, even with starting and stopping in the staging lane. At Bakersfield (101F day temp and no radiator fan), I had to run the engine continually up through the staging lane, right up to staging. They were moving the lanes real quick. The temp was over 180 for that run. Actually, closer to 200. That's really more temp than I feel comfortable with.

Let's think about what would happen without the intercooler.
What heats up the intake air above ambient? Mainly, boost pressure. Compression of the air. At the starting line, when the nitrous hits, there is no boost yet. Regardless of whether the intercooler is there or not, the turbo has not yet had the chance to heat the intake air in preparation for the nitrous hit. Removing the intercooler would have absolutely no effect at all on how the nitrous is vaporized at the start of the hit. No boost has had a chance to build. Remember, We're using the nitrous inorder to start making boost sooner. If there is something I'm missing, please explain.

As far as the intercooler holding the car back. I really don't think that is happening. When the turbo does begin to build boost (after 2 psi), it takes off like a rocket. Boost rise is a straight line. When not properly controlled, there is more than enough power to overcome the 1-2 shift. So again, I don't see an advantage to removing the intercooler.