Supercharger - Ignition/Timing help

[Mad_Man]

Aupercharger becomes inefficient and you got stock cams.... Only way to get top-end is to get some cams. Get some crower v2 no need to change anything. $330 I paid $430 because the were the first batch....

Maybe. I'm still thinking I need some timing back above 3.5-4k.

Anybody else?

[Florida240sx]

If boost drops off then yes. I'll do a vid of my mdm techtom. With timing and rpm. It'll show how it acts..... but this is a ka24de with crower v2 cams and 8.8 pistons. also it's a turbo....the sound of the wastegate will let you know when boost is made Going to try to get on a dyno this saturday, if not I'll do a "scientific test" to see how timing changes in my car while under WOT

[Mad_Man]

If boost drops off then yes. I'll do a vid of my mdm techtom. With timing and rpm. It'll show how it acts..... but this is a ka24de with crower v2 cams and 8.8 pistons. also it's a turbo....the sound of the wastegate will let you know when boost is made Going to try to get on a dyno this saturday, if not I'll do a "scientific test" to see how timing changes in my car while under WOT

I recently turned up the boost controller so that it is above the max boost that the supercharger makes. It is set at 12psi, and the supercharger makes 11psi under full throttle. At the moment, the boost controller is preventing any boost spikes, as it is possible to blip the throttle in neutral and make 15psi.

Anyways, boost remains constant at the max 11psi from when full boost is made (3000-3500rpms) throughout the rest of the rpm band. The only issue is that above 3500rpms, which i don't really consider the "top end", it is very noticeable that the rate in which the power/torque are increasing drops to nothing. Essentially, there is an extremely satisfactory pull up until 3500rpms, where any point above that feels exactly the same as 3500. There is a noticeable "plateau" so to speak, which IIRC the dyno graph illustrates.

Anybody have an opinion on the timing? I'm waiting on someone to comment on my theory 4 posts up.

[watty]

The problem you are going to have is that you need to add timing in cetain places in the map and take it out in others. This will also need to vary by engine load(boost). The MSD programmable thing looks like it only adjusts the advance per rpm in a linear fashion. This might help some, but I'm not sure it is what you are going to ultimately need.

Here is a link to some good timing theory: http://forum.bikirom.com/viewtopic.php?t=380

Read through that and try to visualize how exactly you need to adjust your timing.

Watty

PS I'm shooting you an email in a little while, keep an eye out for it.

[WDRacing]

Just so I have a firm grasp on everything. I haven't posted because I am unclear on how your car is actually running. So this post is assuming everything is in good running order.

Exactly what do you have done to this motor aside from adding the SC. I need details on fuel management and ignition control.

I still say the BTM is EXACTLY what you need. Its that or buy a system that allows you to tune the entire ignition map. But the BTM is a proven piece.

I'll wait for your answer before I post anything else.

WD

[Mad_Man]

For a little additional info:- 1992 240sx w/KA24DE- m62 blower from Xterra/Frontier- Integral bypass valve set at 12.5psi- 2.5" Aluminized Steel Intake Piping w/ Silicone bends and 2.5" x 6.6" Cone Filter- Stock s13 MAF- 480cc Deatchwerks Injectors- Walbro 255lph fuel pump- SAFC-NEO Air Flow Converter- Boost Gauge, Oil Pressure Gauge

As for the running condition, everything runs just fine. The car idles at around 700rpms or so when warm (still need to add IACV-Air Regulator unit for when its cold). There is no hesitation when revving throughout the whole rpm band. The only issue to speak of is that instead of a linearprogression of power until redline, its really the same from 3500rpms up.I think the graph may show that, but I think its a little smoother that thatsince I redid the timing that the dyno guys changed since now its idling and it stopped pinging of any sort at two lines. I can lower the timing to one line, but then it pings from 3500-4000rpms. That is the only place on the whole band that it would ping at though, one line retarded from stock. Could I eliminate that by leaning out or enriching the fuel in that spot?

I also came to agree that that particular MSD unit may not tune enough,and I'm was/are looking for something along the lines of the MSD Digital-7Programmable Ignition, though that is quite pricey. My much preferred solution would be with some type of dedicated ignition controller.

[WDRacing]

Is the ECU pulling timing because its seeing knock? I know you can't be sure, but I'm willing to bet it is.

If I was in your shoes, I'd install a MSD6 BTM and set my timing back to stock. Let the BTM pull out timing on boost. You can set it to pull anything from .2 to 3 full degree's of timing per lb of boost. Retarding base timing is always a bad method.

If you're wanting to invest some cash, lose the entire management setup you are currently using and get a standalone. The MSII is cheap and proven, the AME EMS is expensive but its a direct bolt on. The Emanage Ultimate is the best piggy back on the market that does Fuel and Timing.

Those are definitly better options then buying the Digital 7.

While you're spending, buy a wideband O2 meter. Its THE BEST thing I've ever purchased. That way you'll know exactly what is going on at what rpm.

Oh, snap some pics and post them up. I really like this idea.

I was thinking a twin charged setup would rock. The SC provides instant boost, allowing the use of a HUGE turbo and no worries about lag. Makes the TO4R I have sitting here alot more appealing.

WD

[Edub1]

The first thing I would do is drop the boost down to 5 lbs or so and set timing to stock. Then see how she runs there. This way you won't have any knock and you can see if things are square. Then get your A/F ratios right 11.5-11.9 durring boost. Now it should pull up to redline. If not, the supercharger might be gassing out or creating excessive heat. How big was the motor it came from? Are your pulley ratios close?

If it straightens things out, you can increase the boost a little, but to go over 8lbs or so you'll have to pull timing somehow. You shouldn't need to retune your fuel to increase boost.

Also, you might need to reset the ECU if it went into limp mode.

[watty]

I agree that the BTM is probably the easiest way for you to go. Actually, it should do a really good job for this setup. This will definately help your gas milage and off boost response. And for everyone who reads this, start saving for a wideband O2. It is the best tool I own. We were able to street tune my car in about 6 pulls down the road with the wideband. I stuck it on the dyno and the sniffer showed and rock solid 11.2 which is exactly where I set it.

If you are feeling adventurous, give the MSII a try. It is going to be cheaper than several piggyback boxes. You may need to regroup and lay out a plan for the future of this car and others. Visualize where you want this car to be in a couple of years and start buying in accordance with that.

Watty

[KATwo40]

The more I investigate the MS2, the more I'm steering away from it.

Main reason: The stock ECU has 16x16 mapping and the MS2 has 12x12. That's quite a drop in resolution.

Yes, the MS2 will still interpolate, but those areas of interpolation might be places you need to fine tune. This concerns me.

Other than that, the aux. controllers are great on the MS2. Maybe they'll come out with programming that allows for 16x16 (or larger) mapping.

[obby]

The megasquirt doesn't make too much sense for nissan ecus that can have a bikirom usb installed. The only clear advantage I see with the megasquirt is custom programmability(though biki is making progress in this area, i want my knock klaxon, dammit). Also, on top of all the rewiring and assembly, another potential issue is that the developers of the megasquirt are shifting focus to the ultramegasquirt project...

[watty]

I was just looking at your dyno graph and it looks a little screwy. Do you have another one that is more clear? Also, can you get one that has hp on one side, torque on the other with rpm at the bottom and air/fuel on a separate graph. I watched a Cobalt SS dyno yesterday and the graph from that car looked almost identical to mine just shifted. Here is mine:



If you can get a more clear dyno graph, we might can get a better picture of what is going on.

Watty

[Mad_Man]

Heres the graph that includes HP and TQ. It took awhile to get becausemy scanner/printer working correctly. The reason the scans weren't clearis that the printouts that I got from the dyno were printed quite faintly.I couldnt make it any clearer, so I zoomed in and edited the numbers forbetter visibility.

Clearly there is an issue midway through the graph. Torque isn't levelingby any stretch of the imagination and the horsepower obviously dies outway before it should. So, back to the original questionl: Whats going on?

The AFR on the same scale goes:14, 13.6, 13.2, 12.7, 12.3, 11.8, 11.4, 10.9, 10.5, 10.1, 9.6 from top to bottom.

[WDRacing]

The AFR should never go below 11. Thats the only thing I can tell you bro. If I was there to assist in the tuning, it would be WAY easier.

I think the ECU is pulling timing out, possibly because of knock.

But without a scanner, you won't be able to tell.

[Mad_Man]

AFR is perfect, hovering right above 11 up until that point where everything goes awry. Its allhappening at that same point.

So does the ecu pull timing at specific pointsautomatically if ping is detected? Every runwe made on the dyno adding and subtractingbase timing the problem area began around3500rpms.

Im trying to keep the costs reasonable on the fixbut I'm thinking an MSD BTM and water/methanolinjection to kill any knock not covered by that. Cooler intake temps would be nice too, but even after spirited drives the intake and supercharger plate aren't unbearably hot to the touch. Does that sound like a reasonable solution?

[Mad_Man]

Anybody got opinions on my idea above? ^^^

[WDRacing]

I've been a fan of methanol injection for years. But with a SC you'll be refilling it constantly if its used for anti knock. I use mine to run high boost.

Your problem isn't one we can troubleshoot. Thats the real issue. Why does the car management get screwy at 3500?

Another thing, you should be running real low boost until you figure this out. Retarding base timing is the worst way to tune. Running as much boost as you are with no cooler is retarded with no timing retard. When the ecu see's knock, it pulls an insane amount of timing out all at once.

Lower your boost, set timing to stock, buy a MSD BTM and start fresh from there.

WD

[Edub1]

Anybody got opinions on my idea above? ^^^

Yes, it's a bad fix. Methanol injection can be used for sick boost applications to push up the knock threshhold but in your case you would just be trying to mask a problem.

What you should do is cut your boost back to 4-5lbs to eliminate the possibility of knock and see how she runs there. If you still have this problem you might want to start trouble shooting to see if you have a bad sensor or something.

You are trying to run what 8-10lbs IIRC. Whith the dist turned back and just over 11:1 A/F you shouldn't be getting knock. I wouldn't hang my hat on knock being the problem.

[Mad_Man]

Update: So I've got some support on the Ka-t.org forums in the new supercharger section as far as the water/meth injection goes. A few of them use it, and they said it would be the best way to run up to 12lbs of boost. There really is no realistic way of cooling otherwise. One Ka-t.org member gets around 1.5 tanks of gas for every 1 gallon tank of water/meth. With an extra 1/2 gallon in the tank I plan to put in the "trunk" I should have a safe margin with a low-level indicator on top of that. Interestingly though, another of the members ran his whole m62 setup on professional engine design software and came up with 275hp with an indexed 248/232 cam combo with no heat issue worth mentioning. This intrigues me, considering that is significantly (50hp) more that I am looking for so its good to know that the potential is there if I should ever want to increase it.

As far as my project goes, I just got an Innovative LC-1 wideband with gauge. I've got plenty of time during the New England winter that has finally arrived to figure out exactly how the engine is doing and do some road pulls when the roads are clear/dry. I'll likely get it running best around 5psi which I set it at now and then get a BTM and up the boost. From there I'll judge whether or not I need water/meth injection if I want to up the boost.

I'm also thinking that a knock meter might be a useful/safe item to have, but I have a question about it. How do you calibrate the sensor with a baseline? As in, how would I be sure it wasn't knocking at all when I ran the baseline noise recording?

[NateDogg]

I got the LC-1 it's a sweet unit. Good choice!

Knock sensor ask JGS Turbo he has a knock light that he uses a lot. Cheap too.

I recommend a fresh set of BKR7E plugs and a gallon of Toluene (from Home Depot) for every tank until you get your tuning squared away.
Modified by NateDogg at 10:02 AM 1/30/2007

[Edub1]

Water/meth injection doesn't actually work by removing heat, it works by slowing the combustion process.

Anyway, have you seen those CO2 intercooler sprayers? Try a CO2 cooled intercooler before the blower - this would cool the air considerably pre-compressor which would increase the charge density even more. I would use a small enclosed IC that gets heavily sprayed with CO2. Like an IC in a box.

[WDRacing]

So instead of refilling a methonal resovoir you're refilling a CO2 tank...hardly worth it. When you run empty, you can't just go to Walgreens or Home Depot for a refill.

I have been using alcohol for ALONG time. The key is using it for running big boost or simply instead of race gas. The thing is, you don't want to use it as a bandaid fix. Which is what you'd be using it for. The SC will be in boost ALL the time. So the alky will be spraying all the time. I'm telling you, you'll be tired of refilling it after a short time.

The guy on the other forum probably had his car running well before he decided to go for methanol. So he's using quite a bit less.

I don't wanna piss in anyones cherios here, but you should really be able to run a decent amount of boost if you have timing retard and the tune doesn't suck.

WD

[Florida240sx]

I got a btm I bought to use and has been settign for a year now in my room. Hope I can find it...Wish I was there to help you tune.

[Edub1]

I agree. Ultimatly any system that uses consumables is going to suck.

Question is, how much heat does this unit make?

I would either run less boost or make the adapter plate into a water jacket and run a few thin heat sinks through the ports. Add a small water pump and reseviour and radiator of some sort and have a self contained water cooled system.

However you do it, I'd do it without consumables if possible. BTW, nitrous is the best coolant.

[WDRacing]

I was thinking about water injection being the best anti knock idea if the current setup remains where it is. It only takes a small amount injected to knock down temps about 350* F. This would last longer and give you limitless pump options. Plus the SC won't lose boost with the drop in heat like a turbo will. I could rig a water injection kit for about $125 and thats a decent one.

If you need help with this type of setup no matter whether its water or alcohol, I've got experience with both. Just ask...

WD

[Edub1]

I was thinking about water injection being the best anti knock idea if the current setup remains where it is. It only takes a small amount injected to knock down temps about 350* F. This would last longer and give you limitless pump options. Plus the SC won't lose boost with the drop in heat like a turbo will. I could rig a water injection kit for about $125 and thats a decent one.

If you need help with this type of setup no matter whether its water or alcohol, I've got experience with both. Just ask...

WD

That supercharger adds 30CHP to a 3.3L motor. So the problem might be that he is simply expecting too much from it.

How much water is typically injected? Those types of calculations are normally based on extensive measures such as joules rather than intensive measure of degrees. How much air mass are we talking about and where does the heat go?

[WDRacing]

The heat is absorbed by the water. You obviously start with a small jet/nozzle and watch for EGT drop. If the EGT's stay at or under 1000* you should have no detonation.

[Mad_Man]

I got a btm I bought to use and has been settign for a year now in my room. Hope I can find it...Wish I was there to help you tune.

Let me know if you find it, I would be interested in buying it off of you.

The SC will be in boost ALL the time. So the alky will be spraying all the time. I'm telling you, you'll be tired of refilling it after a short time.

The supercharger really isn't in boost all the time. It has the integral bypass valve that opens (so boost cannot be made) either under boost (at whatever I set it at with a manual controller) or when a certain level of vacuum is felt. It is always at that certain high level of vacuum unless I'm like 70-100% throttle. Especially in gears 3-5 it is extremely easy to stay out of boost, and in normal driving it only makes boost if I want it to.

I was thinking about water injection being the best anti knock idea if the current setup remains where it is. It only takes a small amount injected to knock down temps about 350* F. This would last longer and give you limitless pump options. Plus the SC won't lose boost with the drop in heat like a turbo will. I could rig a water injection kit for about $125 and thats a decent one.

If you need help with this type of setup no matter whether its water or alcohol, I've got experience with both. Just ask...

WD

I would be interested in what components you use for an inexpensive water injection build-up. I'd probably like to use that when I increase the boost when timing is all sorted out.

I installed the Innovative LC-1 wideband yesterday with a gauge and my laptop. I redid the low-throttle part of the map with no load on the engine and the wideband works great, very clearly responsive to changes in the s-afc neo. I gotta wait until the snow melt to do some 3rd gear pulls down a back road near my house. Once I get that map sorted out, I will see how little base retard I can run (its 1 line right now with 6psi) and then get a BTM and redo it from there.

Basically I am in no rush for the time being, I got plenty of work at school and waiting for acceptances from colleges. This snow might finally be here for a while as well, so I've got time to get it right.

The heat is absorbed by the water. You obviously start with a small jet/nozzle and watch for EGT drop. If the EGT's stay at or under 1000* you should have no detonation.

Is there any way to tell other than installing an EGT gauge?

[Mad_Man]

up ^^

[WDRacing]

Water injection is the simplest of all subinjection systems. It only requires a resovoir, pump, tubing, nozzle and hobbs switch to be functional. Maybe a check valve if the nozzle is below the tank to prevent syphoning. Every part you'll need can be purchased at Mcmaster.com, the pump can be any shurflo unit. Just browse around google, there are tons of DIY water injection idea's.

Check out this article, DIY Water Injection

WD