MBC and Bigger Injectors = Turbo

[jayryan]

As most of you know, the AEB engine comes with itsie bitsie tiny weeny 210cc fuel injectors.

Rusty's the pioneer with adjusting A/F to take advantage of the stock ECU's full potential. He's upgraded from the larger 252cc to 310's and now his current 440cc injectors. Chas also did the same upgrade to 252cc injectors, but reverted back to the stock injectors due to incompatibility and rough running with his chip programming.

Thus, I am now the keeper of Rusty's old 252cc fuel injectors. These are Ford Denso injectors with a different spray pattern than the stock Bosch injectors. This makes the idle rough. Rusty has assured me it will run fine though. As I said, Chas had further issues due to his chip program, but Rusty stated that if wasn't racing, he would have stuck with the 252's at least that's what he said in the past. I'll bet he'll keep his 440's though :wink:

These 252's will be going in on Sunday with Mark's help. Along with this, I will be increasing the boost via Dawes Devices Hybrid Manual Boost Controller installed inline with my wastegate and N75. Most of you know how a MBC works so I won't get into that.

The reason I'm opting for this setup is that if I can maximize my current programming, I'm going to try and do that. I've got some room to move on my ECU. Projected boost is 12lbs. = 0.8bar. Ironically, for about $200 more, I'd get the same with a chip, possibly a little more. My car is not a race car, but could use some more boost. So I think (hope rather ) that until something goes out, this will be perfectly fine for me.

I will let you know how it feels and I'll want to log some numbers and compare to Rusty and Chas' so I know I'm in the ballpark. Plus since they're number geeks, I know they'll want to see it. I'm going to dyno this spring at some point after I get a couple other things done.

One of the most exciting parts about this for me is that after two more engine mods, my peformance modifying will be complete. So I'll post on Sunday night or Monday how things feel. This will be fun. And just for the record, since I put in my snub mount, my car vibrates anyway and I like it, so maybe the rough idle'll be kinda cool

Thanks Rusty for the injectors and all the info I scrounged up on CB5. Ditto for you too Chas. Your info when you did this was very informative as well.

[92UrS4]

Looking forward to the results, and pictures of your grin when you achieve that boost.

[the_russian]

Good luck with your set up. Isn't 12 psi is where our computer cuts out?... caz i'm running MBC with stock injectors pushing about 10-11 psi but if i try to go higher it cuts fuel. For some reason not a lot of people like to pu MBC on our engines even though you can get power outputs close to the chipped cars for way less money...Go figure... Well good luck.

Alex

[jayryan]

Alex, Yes. You're right. 9-10 without injectors is the max until it starts cutting fuel. I can push 12 with the bigger injectors.

If I go bigger, fuel will be cut because the ECU's reading incorrect A/F ratios. I'll have to start modding the MAF and go with a rising rate/adjustable FPR like Rusty's Cartech to correct leaning out on top and taking full advantage of 310cc+ injectors.

I took these shots with my phone, sorry they're dark:

[the_russian]

Well good luck with it let me know how it goes.

Alex

[gragravar]

One of the most exciting parts about this for me is that after two more engine mods, my peformance modifying will be complete.

JR this sounds like fun, but I don't believe you will be complete with your modding after this.  Admit it, it is a sickness we all suffer from.

let us know how it goes.  it sounds like a worthwhile change.

[jayryan]

One of the most exciting parts about this for me is that after two more engine mods, my peformance modifying will be complete.

JR this sounds like fun, but I don't believe you will be complete with your modding after this.  Admit it, it is a sickness we all suffer from.

let us know how it goes.  it sounds like a worthwhile change.

I clarifyed it..I've got two other things on the list and then something's going to have to break :wink:

[jayryan]

I have boost :twisted:
I have intake noise
I have DV noise
I have 13lbs.
I have no chip :twisted:

[coveredbytheblood]

Nice.  So, how much did the alternate route cost you?

[jayryan]

$55 + your choice injectors.

[madigan]

Pictures

Injectors (210 vs. 252, no difference in size. It's all in the spray pattern)

Injectors installed (Look how shiny.)

Custom MBC (it might look funny, but hey - it works!)

Installed MBC (Sweet!)

10lbs of boost! (This is before it was tweaked to give 13lbs.!)

Random gargage shot.

[the_russian]

Lokking good man. Hey do you have any problems not holding boost at high RPM. Caz my car starting at about 4500-5000 RPM will drop back to stock... May be it's the MBC caz mine is ghetto homemade. Are you gonna get it DYNOed. You should VAG it and see what kind of power you squeezing out.

Alex

[ColoradoB5]

Sweet JR, congrats!  Make suyre to reset you ECU so it can relearn the new setup.

[jayryan]

I do plan on getting dyno'd at some point. There's a couple other things I wanted to do before that happens. I also want to VAG and see how my numbers are coming out the the larger injectors.

I'm at 13lbs. from about 2700-4500 or so and then it's 12lbs. to about 5500. That's just an educated guess at best. I don't have stock boost unless I'm barely hitting the gas. I'll pay more attention the next couple days after it settles in and let you know.

Winston: I'm going to see how it adapts over the next few days. I'm sure it'll settle down. I'll expect I'll be tweaking over the next couple weeks. I had it set a bit higher, but the car just won't do more than about 12-13lbs.

It builds boost so quickly that I have to have feather foot when just cruising, otherwise I'll let off the gas and get jolted. BTW: I just took it out again and spiked at 14 :twisted:

[Chas]

Take it slow JR. It's better to creep up to the max with this kind of set up then to just leap up to it and then pick up the pieces of a broken turbo or worse.

Peaking at 13 and then having settle back down to 12 or lower is quite normal for our cars. Mine will hit 18psi evry day but as it approaches redline the boost tapers off to around 11-13psi before I shift. that's just the way our ECUs were designed.

[jayryan]

Yup, Chas, I agree. After that night, I backed it down to around 11-12. I spent most of the ride home yesterday tweaking as my car figured out what I did to it.

So...

I hold at 11 and will get up to 12 right away.
6000rpm is right where I taper off to 8-9. I believe when I shift circa 5500, I get the most bang.

Since yesterday, my car will not let me go over 12; it starts bucking and cutting fuel ie. limp.
On the upside, I see little to no spike and little to no boost fall off in the higher rpm.

That, I'm very happy with. It spools quickly, smoothly and virtually immediately with only the smallest amount of lag.

Here's something that really opened my eyes to how detuned our engines are from the factory:
When Mark and I first took the car out, I forgot to plug the N75 back in. I was boosting at 5, spiking at 6. Those are the same numbers I had when I was stock. :?

[DenverPat]

FYI~
According to the dyno at MAC Autosport, my AEB makes 295 ft-lbs of torque and 245 hp.  I've retained the stock injectors and run a 5-bar FPR.  I don't know much about this, but there seems to be some kind of misconception about injectors here.  I get the feeling some people think this kind of power is not possible with the origianal injectors.  What's up, am I not getting something here?

[jayryan]

I refer this to Rusty so nobody else has to read me being an idiot...and my damn back hurts too.

[DenverPat]

What do you mean, "Rusty experimented with different FPR/Injector combos and found this to be the most effective."  In what way is this the most effective?

[jayryan]

Rusty's on the boards, maybe he'll lay it down. It has to do with how soon you hit the injector ceilings. I think it hits later with larger injectors allowing less lean at WOT...I'm a rookie in all this but it's wonderfully fascinating.

...this yogurt I'm having is nasty...

[Rusty]

The AEB engine also calculates A/F by reading from O2 and Fuel sensors and not direct fuel maps which makes chip programming a bit harder than the later cars.

a 5bar FPR and stock injectors is the same as 440cc injectors and a 2bar FPR or thereabouts (Rusty's setup).

...This is maintained by the ECU's reading of o2 voltage and air/fuel.

On the stock programming, if the car sees too much fuel vs. o2, it will cut the fuel (limp) and vice versa, but it can only add so much on stock injectors. Add more air (COAM etc.) add more fuel and the ECU will not see a problem and will allow more boost (based on RPM- hence fuel).

That's one reason why the AEB's are harder to program than the other cars. We don't have set "fuel maps" we can just manipulate.

JR, for God's sake, please... just...  STOP!!!!  None of these statements have even the remotest connection to reality. *poke**grin*

Pat, I suspect that the reason your AEB works well on stock injectors at 5 bar is that, since you have an Owdy, they must be larger than the stock injectors on a VW AEB.  Ours are 210cc.  Do you know what yours are?  Or, your Audi isn't subject to the 16.32 msec injector ceiling that our VW's are.  The Euro VW's don't have this 16.32 ceiling, only the American ECU's.

There is no such thing as "limp" on an AEB.  You can get overboost, which cuts the fuel and causes bucking, even though there is no charge-pressure sensor.  Here's a link that explains it all: Charge Pressure Codes on AEB?!

The engine cannot calculate A/F from reading O2 and fuel sensors.  What fuel sensors?  Did you just make this stuff up? (Please take all this with a sense of gentle friendly ribbing, like I'd be doing if we were all sitting around drinking beer and talking to each other in 3rd person...)

AEB's are not any harder to program than any other car.  They use the same fuel maps as any other car.  The chip tuners can't get as much HP out of an AEB as easily as other (DBW) engine codes because of the small injectors and 16.32 msec ceiling.

All that said, JR, welcome to the heretical world of no-chip tuning.  Just please don't spread the gospel 'til you have it right.

[Rusty]

What do you mean, "Rusty experimented with different FPR/Injector combos and found this to be the most effective."  In what way is this the most effective?

I don't know what JR meant... LOL!!!

[jayryan]

Dammit- so much for the shit I read on CB5...it makes sense in my head at least....speaking of beer....

[DenverPat]

Pat's not sure if his stock injectors are 210 or 310 or gamma alpha beta.  Like Pat said, Pat doesn't know crap about this.  So Rusty, are you saying there's possibly a difference between the AEB they put in the A4 compared to the AEB in the Passat?

[Rusty]

Hey, Pat - according to the latest dyno I have from you, you're running

225 WTQ @ 5000
187 WHP @ 6000

Is this still valid data?  And what boost are you running to get this?  I've been using your very nice dyno as a target, and I've pretty much nailed it!  Check out what I'm running with 15 lbs:

[Rusty]

Pat's not sure if his stock injectors are 210 or 310 or gamma alpha beta.  Like Pat said, Pat doesn't know crap about this.  So Rusty, are you saying there's possibly a difference between the AEB they put in the A4 compared to the AEB in the Passat?

LOL!!!  Rusty is saying that he doesn't see a snowball's chance in hell that you are putting up those kind of numbers with 210cc injectors and a 16.32 msec injector duty cycle limit.

You can test the 16.32 limit easy.  Do WOT from 2000 rpm to redline inroubles 4th gear, while logging block 002.  Does it peg at 16.32?

The injectors could be easy - go look at them, if they are dark green they are 210cc, if another color they're something else.  If you have a Bentley for your car, it will give you the flow rate in the "troubleshooting" section.

[Rusty]

Dammit- so much for the shit I read on CB5...it makes sense in my head at least....speaking of beer....

LOL!  You're allright, JR!  Kudos for trying something different!

[DenverPat]

I normally max boost at 20 to 21 psi. Once in a while I'll spike to 22 or 23. I have yet to put in race gas with this setup. It usually tapers to around 15 or 13 near redline. My car has always boosted differently depending on the weather, so consider these average numbers.
Because I'm having trouble posting the graphs, just click here:
http://forums.audiworld.com/rockymtn/msgs/32563.phtml
then on the small 7507 in blue.  Scroll down to the bottom.

[DenverPat]

After searching AW, I have confirmed my stock injectors are the same as the Passat's (210 cc).  That's what I thought all along.  So, how do you explain the numbers now?

[Rusty]

The pictureposter links don't work either...

OK, I can believe 210.  I can also believe that you have a 16.32 ceiling.  I could also beleive that, since the euro AEB's have a 21.xx limit, that you could also have the 21.xx limit.

If, indeed, you have 210cc, 16.32, then you have stumbled upon a tuner who knows what he's doing.  Or, you've stumbled upon a tuner that found a way around the 16.32 msec limit, which means you have stumbled upon a tuner who knows what he's doing.  Or, you have carefully and wisely selected a tuner that knows what he's doing.  *bow* *bow, WOW* *bow*