Blog

Vacuum Pump Equals HP Gain on the LS6

Mon, 18 Jan 2010 05:17:00 -0500

Note: this is a draft and some sections need to be clarified and rearanged, but you should still get the idea.

On a recent thread, we were talking about the oil ingestion issue with the LSx. I had stated that the vacuum pump offers upto like a 40hp gain, and was question why; hopefully this will help explain why. Most are aware by now that our motors will ingest oil. If your still in doubt, take your TB off and stick your fingers in for oil, and/or look with a flashlight. It seems to puddle right behind the TB on the bottom of the intake plenum. The LS1 is worse than the LS6 and later LSx motors. If you have an early LS1 change over to the LS6 style PCV system at the minimum, for a slightly better result, though not a complete fix. However, the LS6 has a problematic oil ingestion issue itself, though due to another design matter not as bad, which we will cover later.

Many have tried various fixes for this issue, but to no avail. These fixes included, single catch cans, dual catch cans, larger valve cover breathers, eliminating the PCV (not rec. unless with a vacuum pump), and hybrid designs. Some of these fixes actually help with the oil ingestion problems on N/A applications, however, none eliminate it totally. The real issue in this article is concerning a nitrous motor, which can cause this issue to become worse .

We do not want this puddle oil introduced into the combustion chamber when we are spraying the motor as it can and often does invoke the dreaded detonation. Detonation can be the end of a sprayed motor quickly under certain conditions and at certain times. Just watch a LSx nitrous car, boosted car or even a N/A car do a pull on the dyno and you will see the oil being burned and spent out the exhaust. In addition, for those with a dedicated, and sometimes stock, N2O motor, looking at the oil-fouled plugs will indicate oil present. Mechanical issues should be eliminated as a source of this oil by doing a cylinder leakage test if you think this is needed (look in your intake manifold 1st).

For longevity sake and to have the safest nitrous motor, eliminating this oil in the intake must be considered. Some of the fixes mentioned can minimize this oil collection, and some claim the dual catch can be the best fix outside of the vacuum pump. Therefore, that is one great reason to run a vacuum pump, the oil ingestion issue, however that is not the only reason to consider the vacuum pump.

This next section refers in large part to a loose dedicated nitrous motor. The heavier we spray our motors the higher the cylinder pressure becomes and the higher the force pushing past the rings, and thus more contaminates getting into the lower block (not to be confused with blow-by coming past the rings and getting into the intake, which is covered later). You will see the results of blow-by coming out your breathers (if you have installed a nice large valve cover breather). If you haven't added breathers to your nitrous motor, you should. The stock PCV system normally gets its "IN" air via a small line at the TB. This will be filtered air supplied by the air cleaner or CAI. This is a closed system like the government wants for pollution control; however, it is not enough breathing capacity for a nitrous motor. Therefore, what happens is this internal pressure is trying to be relieved and will find compromised gaskets as an escape route and result in oil leaks dripping here and there. A nitrous motor needs to breath, so even if not modifying the PCV system a nice large valve cover breather is needed (see picture). Some add one to each valve cover.

So now we know the two reasons for adding a vacuum pump, one is to stop the oil ingestion issue, and the second is to allow a nitrous motor to breath properly. It is the second reason that will allow us to pick up some additional HP compared to a non-vacuumed pumped motor when spraying, and even a slight increase N/A. One recent magazine article showed a 40rwhp dyno proven increase by just adding a vacuum pump (I will try and find the magazine and ink). So now we can talk about why and how the vacuum pump can increase performance, but will need to cover some basic short-block engineering first.

Remember when it was stated that the improved LS6 PCV system was a good choice over the LS1, but still did not help the LS6 motor more than the LS1. Here's why. As the pistons move up and down, they force air in and out of the bays beneath the pistons. At high RPMs this airflow becomes quite violent and really whips the oil up (more oil to get to the intake tract). It also results in parasitic HP lose trying to fight this turbulent mix of air/oil and internal combustion contaminants. Due to a deep skirt design (block structure extends past crank centerline) the LS1 has machined windows between the bays. Now the LS6 was going to be spinning higher (think of your built motor going even higher and n2o motors allowing more combustion contaminants past the rings into the intake) and needed even bigger windows, But couldn't tolerate the strength lose with bigger windows. What they did was to engineer valley mounted oil separators which uses internal baffling to force the crankcase vapors in a circuitous (think roundabout) flow. This in turn causes the oil to separate and drain back into the engine. Does it work? Well it may work, but because of the higher output of the LS6, it doesn't seem much better than a LS1, or it may be much worse with out this extra system. The real fix is a vacuum pump and especially for a sprayed motor and high-performance high RPM N/A motors.

In closing, the LSx series engines are well known for a lot of blow by and resultant contamination of the intake charge with oil forced past the rings into the combustion chamber. The vacuum pump eliminates the PCV valve, allows the rings to seal more effectively, and reduces oil contamination of the intake charge, which results in added horsepower. A side benefit of the negative crankcase pressure the vacuum pump creates is that it also helps to eliminate unsightly oil leaks.

This is just a rough draft, and it will be fine-tuned later. The above info is off the top of ones head...

Robert

Spark Plugs Reading and Choosing-Part 1

Sun, 10 Jan 2010 04:05:00 -0500

I am currently involved in a thread about choosing the correct heat range plug. The thread has developed to the point where I want to talk about tuning and what the plug tells us in more depth. So I was going to post about the "Fuel Ring". Anyway, I had a small section on the site about plug reading, and had been collecting data for a few years, however I have never had the time to add this new data and present what I know. So I figure I can do that here in the blog section and later gather all my notes into a plug reading article. Here is part one, the "Fuel Ring". Remember this will be the rough draft, and may not contain everything the write-up will, or rather this blog may not be as in depth as it will be later.

Spark Plug "Fuel Ring"

The porcelain on the spark plug will have three sections that can be read, however, concerning racing and nitrous we will only be concerned with the third or deepest porcelain area which is our A/F ratio ring. Closet to the tip of the plug is the idle zone, and can be colored differently for various set-ups, however, we need not concern ourselves with this area. Though of note, if yours is grayish colored that means you drove back to the pits, not what we want, and more on that later. The middle section I like to call the cruise area, and again the racer/sprayer will not be concerned with what it looks like, and you will understand why soon. The area we want to look at is the third and deepest area inside the plug-porcelain.

To understand the Fuel Ring, we must first see it. There are two ways to do this. First, a lighted magnifier of good quality can allow looking deep down inside the plug. The second method is best, and will leave no doubt in ones mind. It requires cutting the outside threaded jacket completely off the plug. This can be done with a Die Grinder or simply by using a hack saw. The picture below shows what a plug looks like minus the outer thread jacket.

Once viewable, we will see that the 1st and 2nd sections are cleaned off from the 1/4 run that was just made, and shutting down thereafter (remember lead paragraph and the grayish coloring?), then pulling the plugs immediately and installing replacements or towing back to the pits and pulling. The ring starts at the top and works it's way down, cleaning the 1st and 2nd sections as it reaches the point where the porcelain meets the jacket area. It will get colored only at WOT and the Fuel Ring should be closest to where the porcelain meets the metal outer jacket area. Color is dependent on fuel type and brand. The picture looks to be VP as this fuel normally colors light gray. What ever the color, it should be shadow like. Making a couple to a few passes may be needed to set the Fuel Ring. There is another ring that sometimes comes into play.

We don't want to get the Fuel Ring mixed up with an oil ring. Some motors, and in particular the LSx platform, can ingest oil and have an Oil Ring. This ring will look like a lightly oiled ring and will be right next to the metal jacket. this ring has nothing to do with reading or setting the A/F ratio. A loose nitrous motor with a lot of blow-by may be a culprit too.

Today we have a companion tuning tool for this Fuel Ring reading, and this is the Wide Band. They go hand in hand, IMO, tuning the correct A/F ratio for your car. I know your wondering why I haven't stated what your ratio should be. Well the reading and locating of the fuel ring is what we are looking for. Generally when the nitrous company says use this ratio or a tuner that ratio, its generally a safe A/F ratio that will keep most whom will not be reading their plugs safe. However, that will not always locate your fuel ring, so it's up to the end user to use all the tools they can to dial in what your car needs and likes. What we are finding with the LSx platform is they work at a higher Volumetric Efficiency with a leaner than normal A/F ratio, compared to motors of past.

Where the rule from the street/strip vendors may be 11.2 to 11.5:1 A/F ratio, the LSx actually runs better with mid 12.X:1 A/F ratio, and some are even going leaner (at least those in the know). Think of it this way, why on earth would you run an overly rich nitrous hit when your N/A maximum power is made with a 13.2:1 A/F ratio. The reason the LSx can run leaner sprayed A/F ratios has to do with how good the cylinder heads are, or how good the breath. A stock LSx motor can easily reach the .450 Brake Specific Fuel Consumption (BSFC), and only fully built race motors a few years ago could attain a BSFC like this. Now we totally blueprint and balance our LSx and the VE goes even higher. The point here is this, what the vendors and nitrous companies recommend is not necessarily what our LSx will need or like; and the main reason we want to be able to read our plugs, so we can dial in the highest power and do it safely. Looking at the plugs along with recording our WB will allow getting our tune spot on. Once we can do this we can also move up in the size of the shot and do it with ultimate safety.

One other thing to look at while we have the jacket removed is the porcelain itself. It should have a chalky look as normal. If it has a shine that means things have got hot and melted the glass in the porcelain. Another glazing appears more glossy like and will have spots and may be caused by excess idling and/or incorrect A/F ratio. Both scenarios mean plug replacement is mandatory. Otherwise, shorting out during a run is possible and a resulting misfire. Ever wonder what one of the cause of ring lands lifting is, and why popping/backfiring out of the exhaust happens, yes, glazed porcelains in the answer.

In closing, this is the rough draft, and I will certainly be fine tuning and adding much more info on reading the plug and selecting the correct heat range in part 2 and what timing to run in part 3. Please if something doesn't make sense, let me know, or if something seems off let me know as this is written off the top of my head. We will compare to my notes and data later. Here is the picture of what we are looking for.

Robert

Dry Nitrous Tuning via Interface and/or Tuner Programs

Mon, 04 Jan 2010 03:10:00 -0500

This is just a clip from a very interesting and informational Dry tuning thread. I will link the entire thread at the bottom, but thought this clip would spark some interest. One of the best up to date dry tuning threads out there, enjoy.

Quote:

Originally Posted by C5_Pete

Please dont take this the wrong way, as I'm VERY impressed with the knowledge you guys have when it comes to tuning and EFILive/HPTuners. And your understanding of all things nitrous related.

My question is. While using resistors or diodes or what ever, or wiring into the car's PCM, just to tune for the nitrous hit - isnt it easier to just use the HSW Interface? Plug it in - hook up a couple wires to your controller, and you're done... Seems easy to me... But I'm a noob, so I'm still learning...

Thanks

Yes much easier than the resistor tricking methods, no doubt, and much more sophistcated. Where the Interface really shines is in the cost area. You can completly tune your nitrous with out the need for an expensive full tuner program. There just isn't another product like it on the market. The kits that include the Interface are fully self contained, meaning, you do in fact have everything needed to set up your nitrous kit, and the ability to fully "SELF" tune. This is a brand new concept in the nitrous world. Now if one wants to purchase a full tuner program, the Interface offers some advanced modes IE: set-up and save as many custom timing curves as you would like. Also, should someone want to take the route of the full EFI Live Cos 5 program and omit the Interface all together, that is a good option too. However, many can not afford a full tuner program, so having options is great. One thing to point out, I would always verify the A/F ratio with a WB no matter which controller/program is used. What is commanded, and what we see, is often slightly different.

Quote:

Originally Posted by minytrker

I like to keep things as simple as possible and still do it safely. I have hade efi live and hpt tuners for years before the interface came out. I can do COS#5 for less than $10 using the stock pcm vs buying another box to hook up. Its only one wire to add and a switch. I think the stock pcm is more reliable than any after market box add on.

Agreed. One thing I would like to add, the current generation of piggy back controllers, due to the advanced circuit boards and electronics in general, are pretty darn reliable, IMO, much more so than boxes of just a couple years back. The Interface has a full diagnostics approach, should anything be detected with the box itself, or anything with the cars electronics (MAF) along with the nitrous kit itself, it will not allow activation and give the operator a cue that something is a-miss. Then on top of this, the box itself has full diagnostics to take the end user step by step to find the problem. It does this with a set of diagnostic lights. Actually the Interface is a mini computer and has more computing power than the computer used in the Spacecraft that allowed the first moon walk, true story!

I got some heads up information today regarding the HP Tuner software. It seems they are hot on the heels of EFI Live Cos 5. I have the full information coming, but from what I know presently, things are looking real good concerning the Dry tuning and the Tuner program (and wet hits too). This person is setting up and tuning a dry hit, and I have been helping where I could, but he may be taking me to school, LOL. Here is a small quote from a rather long E-Mail, just for insight:

Quote:

I recently got the advanced version of the Tunning School program for HP Tuners and they show how to tune wet and dry and even how to set up HP Tuners as a sophisticated nitrous controller with WB AFR cut out!! Very sweet!

Robert

Here's the link: http://www.ls1tech.com/forums/nitrous-oxide/1212000-dry-nitrous-tuning.html

Write-Ups Going to PDF Format

Sun, 03 Jan 2010 01:53:00 -0500

Damn, 6 freaking paragraphs and I lost them, damn. I am ticked off so will have to come back later, damn.

Curing the LSx Oil Ingestion Issue: Vacuum Pump

Tue, 29 Dec 2009 03:41:00 -0500

The LSx has an inherent flaw, oil ingestion into the intake manifold. Even N/A this is a problem, then add nitrous and it really shows it's ugly head. Just pull any intake TB off and stick your fingers into the hole and it will likely be covered with oil. The oil puddles on the plenum floor, then when getting on it, and especially when spraying, we see a lot of smoke out the tail pipe. Yes, we are burning this puddled oil. This is not good on a sprayed motor as it is a source of the dreaded detonation.

We have tried all of the fixes IE: puke cans, no PCV valve, big valve cover breathers, dual puke cans and so on. Only eliminating the PCV all together fixes the issue, but that leads to other problems, but we won't go into that at this time. Just don't seal off the PCV system all together for a street/strip motor. The real fix is a vacuum pump.

Until recently there was no good option for a street style pump, they all only lasted a couple hundred miles. But now due to the engineering at GZ, they use the oil mist in the blow by to lube the rotor blades in the unit for very long life. So know we have a true street/strip vacuum pump that can give us an additional 40hp at the wheels.

Watch for a full C5 how-to coming. I have all the info and have done the install, just need the time to put it together.

Here is the lead paragraph in the vacuum pump section:

[QUOTE] Want to stop the blow by from a lose nitrous motor, a turbo(s) set-up, or stop the nasty oil the LSx platform pulls in to the intake? Well, I have the answer for you, and the first dedicated kit for the Corvette and F-Body. Stay tuned, and read on, as I have the 2nd C5 model out on my test Z06, above. These pumps were designed for street applications and work as well at the strip. I chose to upgrade to the Pro Series pump due to a 300hp Dry N2O shot, and having larger than 400ci. See the sizing chart in the Application guide (quick links) if you think you may need a Pro Series Pump for big HP needs. [QUOTE]

Robert

The LS7 Sprayed Limits and Tuning

Sun, 20 Dec 2009 05:24:00 -0500

What I have seen in general with the LSx platform is they like a little leaner than motors of past days. Why? This has to do with BSFC and overall VE from the get go. These cylinder heads flow so well and are so efficient that a stockish n/a LSx motor is seeing BSFC's in the .450 range, un-heard of out-side of race motors not that long ago. Do the math for injectors sizing for the C5 Z06 with the BSFC of .450 and we can easily see that GM knew how good these motors breathed. Then a performance, purpose-built, motor will even have better BSFC numbers and skew the old guard even more. This brings up the second issue, timing.

Again due to the great efficiency of our heads, we need to pull more timing than motors of the past. The LSx platform likes a lot of timing pull. If we don't get aggressive with timing removal on the spray, and get the firing of the cylinder back to the retreating piston, rather than fighting an up-wards traveling piston, we will get pre-ignition that can lead to the dreaded detonation. This early or quick firing is more pronounced on the LSx than motors of old. We need to properly time the pressure spike to the retreating piston. Some of the heavy hitters running the LSx are in the single digit arena for max timing on the spray, and this is still the street/strip realm.

So in conclusion, the standard low/mid 11.x:1 a/f ratio is to rich, and the recommended 2° for every 50 shot is not always enough. Many do not realize that rich can do more damage than lean. This is where the problems arise, we have vendors/companies still recommending tunes that are not correct for the modern EFI motors. They like to use the general blanket statements that worked well in the past, but not absolutely correct for our new-tech motors. Knowledge is power, in more ways than one.

This all brings up running a 200hp or larger shot in multi stage. Given the tuner really knows how to tune the 427 with spray, there is no reason at all why we can not survive a long life by splitting up the torque curve. It is this low RPM torque that does the real damage, compared to the high RPM max HP. The cylinder pressure increase and staying there longer can be the factor that hurts the motor. I contend that a dual staged 200rwhp shot can be safer and easier on the 427 than a 150rwhp all in one off the line shot.

We have set-up dual staged dry hits that mimic the turbo curves for power and torque almost point for point. What does this mean? It means that the sprayed torque can indeed be applied in a nice progressive linear manor, with no massive low RPM spikes. Ultimately this leads to longer life before rebuilds. (see the dyno overlay in prior blog)

I think we will see more and more high HP 427ci motors coming down the pike as more tuners understand exactly what these motors like. Yes, there are those tuners out there already, but there are also those that were left in the early 90's. Technology is our friend, LOL. These are just my opinions, and everyone may not agree, but that is fine. We would love to hear any constructive critisisim.

Robert

New Sections and New Information

Sat, 19 Dec 2009 17:31:00 -0500

Under the "NANO/N2O Accessorys/Info" section (yes, I know it's spelled wrong, but needed that letter number count) is a couple NANO compatibility Chapters. We are gathering info on bottle valves on what works and what does not work. Also, we are stating HP limits of the particular valve brand and model. we are trying to add pictures of each style valve for comparison sake so the end user will know if he has this one, or that one.

Some companies have numerous bottle valves; however, the vast majority have only a version of the 660 standard "High Flow". For instance, NOS has 12 valves that I am aware of. They use currently, outside of the PowerSport valves, 2 valves. they are the Super Hi-Flo and the Hi-Flo, with 550hp and 400/450hp respectively.

We also will add a how to add a gauge along with the NANO one-way, supply, check-valve. A couple different ways to do this on bottle that only have one gauge port.

Check out the new sections as each one will have new information. Hopefully you can glean some insight even if your not interested in that particular section. Upgrades, fine tuning and additions all through out the site.

Robert

Dyno Overlay Turbo vs Nitrous

Sat, 19 Dec 2009 07:40:00 -0500

These are all bone-stock long-block LS6 motors. We were showing how a multi staged Dry hit could mimic a turbos power/torque curves. It does in fact break up the massive torque spike we often see with the "all in one" off the line N2O hit. So, we can add more over all power safely running spray as long as we progressively apply the spray. lets hear what you have to say. GM really got the LSx platform right as my buddy Chris Stewart (author of Overlay) is now pushing just a tad bit over 700rwhp.

Enjoy,

Robert

http://cjstewart4.home.comcast.net/~cjstewart4/Z06_dyno_overlays.htm

Up Dates On Web Site Rebuild

Thu, 17 Dec 2009 07:54:00 -0500

I am redoing my web site and hopefully this will be a positive. Mostly going with supporting/selling NANO only. It is just too much of a hassle trying to sell too many products, but still have all my connections and contacts with all the companies involved. We still support fully, HSW, NOS, NANO and others, just taking a secondary spot with them at this time. The future is still wide open.

We are going to re-open the Forum that was here before, at least for now. It will be only for tech related questions that some may have and have no where to go for a straight honest answer. You won't get the typical vendor answer where they kiss all angles positively so as not to offend anyone. One vendor would do that all the time, play both sides of the fence rather than having the balls to really give his opinion and chance offending someone who gave a different view (that is the dollar driven vendor we despise). However, that vendor was just a forum repeater, meaning, if you really followed along he was just repeating what others had already typed previously, lol. I busted him using my stuff/input under the wrong context, lol. If he really understood the workings of nitrous he would never had made this blunder. I was more than happy to point this out on an open forum. He banned me, before this, from his forum before I could post anything besides a "hello, just joined". Go figure, lol. Not only does he hate the dry technology, he hates me, lol.

More tech write-ups coming. Most have been targeting the beginners, and nothing wrong with that, but some of the new ones will get a little deeper in to the facts, or shall we say more complicated. Also, anyone whom has a tech type how-to or write-up, with correct info, I would be more than happy to host. That's the premise of this site and always has been, to help others. Of course you get full author credits and copyright protection. You can see this a few times on my site where credit is given where credit is due, should someone offer fact/figures/graphs/ full how-tos or what ever. I never claimed to know it all, so any help from others is welcome.

Robert

Edelbrock Intake and Vacuum Pump general Updates

Sat, 21 Nov 2009 22:37:00 -0500

The single plain is installed. I tried the sheet metal elbow, but due to fitments, quality and flow issues have changed to an engineered piece. It's a full flow 100 degree cast unit from Edelbrock, they make 3 styles. More information forth coming.

I missed the annual dyno day shoot out, however, one of my customers did win Highest Nitrous HP with his HSW Dry Plate kit the "Sudden Impact". So no new numbers yet.

Hopefully I will be able to keep up with adding blocs more often. So many new products hitting the market, and I often have privy prior to release.

Oh yea, I also added a Vacuum pump to counter the blow by that the LSx suffers from. I will post up a how-to for the Vette guys soon. it's finished, but just need to find the time to organize as it takes a lot of effort putting a write-up together when using pictures. Actually, I have numerous write-ups in various stages of completion. :tongue:

Robert