S5 4.2 v8 water/meth injection for carbon?

[Zingrox]

The notorious carbon buildup of the 4.2 doesn't really have many ways to slow down the process, how much do you think a water/meth injection would help? Everyone says it "steam cleans" the cylinders and valves, not to mention lower temps and better mileage. Some people do straight water injection to help with carbon.

Think it's worth a try? Sorry if this is covered, when I searched I didn't find any decent threads, it kept pulling up cars and engines from people's signatures rather than thread details.

[Ford Prefect]

The notorious carbon buildup of the 4.2 doesn't really have many ways to slow down the process, how much do you think a water/meth injection would help? Everyone says it "steam cleans" the cylinders and valves, not to mention lower temps and better mileage. Some people do straight water injection to help with carbon.

Think it's worth a try? Sorry if this is covered, when I searched I didn't find any decent threads, it kept pulling up cars and engines from people's signatures rather than thread details.

Hey, have you searched in the B8 S4 section? Carbon build up is carbon build up, if it helps the 3.0T I think it would help yours too.

[Ape Factory]

I've considered this idea for my RS5 as well and I think it'd be great to have a water injection system specifically for carbon buildup. I do wonder about cylinder washing with water injection but I also see production volume cars, like the M4 CS, using it. Maybe JHM could chime in or develop a kit.

[Zingrox]

I think as long as it's set up well enough, we won't have a problem in the world. However I do not know how to properly set this up. Which is where they come in ;)

*Cough* Tech/Sales@JHM any ideas?

I bet everyone would love a kit like this to get rid of those occasional few hundred dollar carbon cleanings...

Sent from my SM-G930V using Audizine mobile app

[430hps4]

Build your own catch can... could help a bit...

http://www.audizine.com/forum/showth...atch-can-setup

[Zingrox]

Thanks for the read, that seems doable

Sent from my SM-G930V using Audizine mobile app

[Ape Factory]

FYI, according to JHM, they already looked into water/meth for carbon buildup issues with the RS4 and found it did not help.

[Zingrox]

Interesting. While the rs4 has a different engine build, it would still have the same effect. Perhaps it isn't as worth it then, thanks

[Ape Factory]

Yeah according to JHM, it had no effect. Real shame, I had hope!

[ZimbutheMonkey]

FYI, according to JHM, they already looked into water/meth for carbon buildup issues with the RS4 and found it did not help.

I'm inclined to disagree with that statement.

I've never seen JHM release any formal testing results. Nor have I even heard rumors of them having tested the effects of W/M on an FSI engine.

Here's some confounds I can think of off the top of my head.

What volume of W/M were they running?
-how many nozzles
-where were they placed
-how long (weeks, months, etc..) did they run it?
-how hard did they drive the car,
-what where the atmospheric conditions
-what kind of fuel and oil were used during testing
-was the car inspected regularily for intake or PCV leaks
-what were the condition of the piston rings to start?
-what was the mileage on the car
-how well were the ports cleaned before testing?
-If there WAS still buildup was it mitigated vs non water/meth control (assuming there was one)

All of this nothwithstanding that water/meth will cool your intake charges DRASTICALLY https://www.audizine.com/forum/showt...it-I-d-say-so-)

36C/100F reduction (and possibly more) in intake temps. at the 1x10F rule, that's 10 CHP in just cooling alone, then add the 4-5 degrees worth of timing you get back, well do the math.... The RS4 is HYPERSENSITIVE to knock and will retard timing if you look at it wrong.

Finally, the real solution to carbon buildup is to reprogram the ECU and eliminate the EGR mode by parking the exhaust cam in anything less than about 70-80% throttle.

The moral of the story is.... Just because JHM hasn't done it or endorsed it, doesn't mean the matter is closed. Think for yourself, do your own research and draw your own conclusions.

[Ape Factory]

I just restated what JHM originally stated when asked, I have no skin in the game. I have no issue with water/meth injection and have used it on past cars. None were DI or had carbon buildup issues. It was strictly for charge temps. So you'll get no argument from me in that department.

[Ape Factory]

I'm inclined to disagree with that statement.

I've never seen JHM release any formal testing results. Nor have I even heard rumors of them having tested the effects of W/M on an FSI engine.

Here's some confounds I can think of off the top of my head.

What volume of W/M were they running?
-how many nozzles
-where were they placed
-how long (weeks, months, etc..) did they run it?
-how hard did they drive the car,
-what where the atmospheric conditions
-what kind of fuel and oil were used during testing
-was the car inspected regularily for intake or PCV leaks
-what were the condition of the piston rings to start?
-what was the mileage on the car
-how well were the ports cleaned before testing?
-If there WAS still buildup was it mitigated vs non water/meth control (assuming there was one)

All of this nothwithstanding that water/meth will cool your intake charges DRASTICALLY https://www.audizine.com/forum/showt...it-I-d-say-so-)

36C/100F reduction (and possibly more) in intake temps. at the 1x10F rule, that's 10 CHP in just cooling alone, then add the 4-5 degrees worth of timing you get back, well do the math.... The RS4 is HYPERSENSITIVE to knock and will retard timing if you look at it wrong.

Finally, the real solution to carbon buildup is to reprogram the ECU and eliminate the EGR mode by parking the exhaust cam in anything less than about 70-80% throttle.

The moral of the story is.... Just because JHM hasn't done it or endorsed it, doesn't mean the matter is closed. Think for yourself, do your own research and draw your own conclusions.

While I have you here...curious about a few things...what programming suite are you using to tune? HPtuners? https://www.hptuners.com/product/mpv...ent_1513038398

I've strongly considered trying them but I don't have readily available access to a dynamometer that can measure hp and torque accurately and I'd rather not do the amount of logging necessary on the streets to zero in on the perfect tune.

When you say "park" the exhaust cam, can you explain further? Does the RS4/5 have variable lift? Or are you simply reducing overlap by a significant amount? Does the RS5's EGR system work the same as the S4/RS4 with which you have experience with? It'd probably be even more effective to just eliminate the PCV recirculation, vent to atmosphere and eliminate the error codes via the ECU programming. But how much do you like the smell of oil?

One caveat, we're referring to the RS5 which has a far different ECU/engine than the S4/RS4. There's very little information and the "shops" certainly don't share any information whatsoever. While we'd all like to be pioneers, it's an admittedly complicated package and there's no knowledge base, or very little, to draw on. I've tuned high hp rotaries where there is zero room for error. Two degrees too much timing and BOOM. So I'm not afraid to tune and certainly smart enough. But do the available programs (to the average consumer) have the ability to access all appropriate tables in the ECU? Again, no one has really tried on the RS5 AFIK. We're all limited on how much time we can spend working on cars. For me there now has to be a balance.

No one has produced a map to incorporate water/meth injection on the RS5. APR only managed nine peak hp (maybe) with all of their resources. JHM made 25 wheel hp on my car. I have no real reason to doubt them when they say they tried water/meth injection to help alleviate carbon buildup. If anything, they would WANT it to work. It'd then be a product they could sell.

I have seen, first hand, an RS4, never carbon cleaned, with 100K miles that sat there and idled perfectly for a good half hour. Not one miss.

But I do agree on the IAT's, the RS5 is also very sensitive to heat and I could see a real benefit to water/meth. I'd like to get up and running on E85 first and go from there along with lowering the operation temperature by 25 degrees, keeping it in the 190-210 range. Baby steps. It's an expensive engine!

[ZimbutheMonkey]

Wellllllll, interesting, someone from the RS world who's interested in tuning...

I just learned to tune Motronic. I even wrote my own definition files in the beginning. I was also the first person (AFAIK) to publicly start experimenting with cam phasing on the N/A Audi engines.

When I say park the exhaust cam, I mean just that. keep it's opening late as possible and the intake opening as early as possible under part throttle. It will hurt gas consumption, but no more than a manifold half full of carbon would.

Really, if you think about it, the only time the intake valves see carbon is when it flows back in during overlap. For that to happen, pressure in the exhaust has to be more than the intake. Unfortunately, with the big pre-cats in place, it's easy to generate more pressure in the exhaust at part throttle say vis a vis a catless set of downpipes. In fact, eliminating the cats would probably mitigate cabon build up a LOT on these engines seeing as they have branched manifolds which encourage scavenging (unlike the B6/B7 S4).

As for tuning, I've spent literally thousands of hours and about 500 different file revisions tuning my two V8 S4's. While I don't want to start a pissing contest, between my tunes and JHM's all I'll say is I have a copy JHM's tune which was given to me, I've studied it and while it's a little better than most, it was nothing earth shattering IMO. To wit, JHM changes about 50 maps, I change just under 100. Now, many of them are 1x1, but still they make a significant difference to transient response by eliminating throttle delays on opening and closing among other things.

You say that APR tried to tune your car for W/M and only made 9 WHP whereas JHM made 25 WHP. Do you happen to have copies of the dyno graphs and any logging data from the two tunes? PM me if you do as I'd be interested to see them.

I myself have tuned an RS4 and it turned out well. I had very, very little time with the car and only had 2 revisions to get it dialed in. However, I spoke with the owner after a few weeks of driving it and he is beyond thrilled with it.

While I didn't get a chance to dyno it. I did get a clean 3rd gear pull on a flat stretch of road for data analysis. I put the results into Virtual Dyno and found this... (note, I took the peak numbers out so as to eliminate the inevitable inter-dyno dick swinging contest)

RS4 TUNED DYNO NO NUMBERS by zimbu themonkey, on Flickr

vs APR
RS4 TUNED BY APR DYNO by zimbu themonkey, on Flickr

Now, I know people will scoff and say "pff, it's only a Virtual Dyno plot" well I challenge anyone to replicate this plot on their own by plugging numbers into a spreadsheet. What you need to take note of is just how FLAT it is. I ran out of road and had to pull the plug around 7300 RPM. However when you compare it to the APR plot (and EVERY other aftermarket tune dyno), you'll note that the torque curve on EVERY ONE of them does not change shape, it just gets raised up. That's a surefire way to know if the cam timing was changed BTW.

Anyway, I hope that at least whets your whistle a little. You can flash your car with a simple $99 MPPS V18 clone cable, use a cracked version of winOLS for editing and if you can PM me your ECU number I can even see if i have a DAMOS file to give you.

I look forward to continued correspondence

[Ape Factory]

Thanks for the reply. Interest peaked.

[Zingrox]

Heck, that peaked MY interest. Didn't think I'd find information this valuable about that type of thing here. I've given this sort of deal a fair bit of thought but never investigated starting due to the 9.1.1 ECU being an absolute pain to me to deal with so far.

[Ape Factory]

Unfortunately for us RS5 guys, it gets even more complicated as we have the Bosh Medtronic 17.1 which is also tied into the TCU. You basically can't tune the main engine ECU without "fooling" the TCU and have to keep it happy otherwise it shuts the parade down. Guess how many people make a TCU tune for the DL501 found in the RS5? Zero. Same transmission as the S4/S5 B8.5 as well as the C7 S7. No one makes an RS5-specific tune.

Will admit, we do need MORE discussions about this sort of stuff. Especially for the later cars, it's a technological black hole.

[Zingrox]

Anything regarding progress on these cars, be it mechanical or electrical, is for some reason kept under wraps until everyone else figures it out

In addition, the module based compliance of the cars hardware drives me insane. Even replacing small things needs long coded. Everything has to smile and wave just right, or it kills connection and use to it

Though I guess I'm preaching to the choir on that, just had to rant a little over it

[Ape Factory]

The most "open" forum I've ever experienced, in terms of problem solving and shared technical information, was the RX7 forum. Without question. The Evo forums were a close second. On the Audi forums, NONE of the vendors ever share any information other than what they're selling. Seriously disappointing.

[Zingrox]

The most "open" forum I've ever experienced, in terms of problem solving and shared technical information, was the RX7 forum. Without question. The Evo forums were a close second. On the Audi forums, NONE of the vendors ever share any information other than what they're selling. Seriously disappointing.

Ross tech forums are pretty good about it, relative to most others. Otherwise, everything else is a massive pain to figure out here. I don't know why the sharing of information is so taboo. Progress made on these models is lead by select individuals like you

[bendilzerian]

Wellllllll, interesting, someone from the RS world who's interested in tuning...

I just learned to tune Motronic. I even wrote my own definition files in the beginning. I was also the first person (AFAIK) to publicly start experimenting with cam phasing on the N/A Audi engines.

When I say park the exhaust cam, I mean just that. keep it's opening late as possible and the intake opening as early as possible under part throttle. It will hurt gas consumption, but no more than a manifold half full of carbon would.

Really, if you think about it, the only time the intake valves see carbon is when it flows back in during overlap. For that to happen, pressure in the exhaust has to be more than the intake. Unfortunately, with the big pre-cats in place, it's easy to generate more pressure in the exhaust at part throttle say vis a vis a catless set of downpipes. In fact, eliminating the cats would probably mitigate cabon build up a LOT on these engines seeing as they have branched manifolds which encourage scavenging (unlike the B6/B7 S4).

As for tuning, I've spent literally thousands of hours and about 500 different file revisions tuning my two V8 S4's. While I don't want to start a pissing contest, between my tunes and JHM's all I'll say is I have a copy JHM's tune which was given to me, I've studied it and while it's a little better than most, it was nothing earth shattering IMO. To wit, JHM changes about 50 maps, I change just under 100. Now, many of them are 1x1, but still they make a significant difference to transient response by eliminating throttle delays on opening and closing among other things.

You say that APR tried to tune your car for W/M and only made 9 WHP whereas JHM made 25 WHP. Do you happen to have copies of the dyno graphs and any logging data from the two tunes? PM me if you do as I'd be interested to see them.

I myself have tuned an RS4 and it turned out well. I had very, very little time with the car and only had 2 revisions to get it dialed in. However, I spoke with the owner after a few weeks of driving it and he is beyond thrilled with it.

While I didn't get a chance to dyno it. I did get a clean 3rd gear pull on a flat stretch of road for data analysis. I put the results into Virtual Dyno and found this... (note, I took the peak numbers out so as to eliminate the inevitable inter-dyno dick swinging contest)

Now, I know people will scoff and say "pff, it's only a Virtual Dyno plot" well I challenge anyone to replicate this plot on their own by plugging numbers into a spreadsheet. What you need to take note of is just how FLAT it is. I ran out of road and had to pull the plug around 7300 RPM. However when you compare it to the APR plot (and EVERY other aftermarket tune dyno), you'll note that the torque curve on EVERY ONE of them does not change shape, it just gets raised up. That's a surefire way to know if the cam timing was changed BTW.

Anyway, I hope that at least whets your whistle a little. You can flash your car with a simple $99 MPPS V18 clone cable, use a cracked version of winOLS for editing and if you can PM me your ECU number I can even see if i have a DAMOS file to give you.

I look forward to continued correspondence

This is awesome. And I really agree/appreciate the cutting numbers out, threads get so quickly derailed by dickheads, on all forums, over the wrong thing.

Catless DP argument for carbon makes a lot of sense. Wonder what the pressure difference really is during the overlap that allows backflow, because it seems 7-10lb from the supercharged group doesn't solve CC. Not arguing that removing cats wouldn't remove at least/more pressure than that, cause I could see that being the case too.

Those are definitely some nice curves. I've got a b7 rs4, and I'd be interested in a nicely cleaned up N/A tune. Looks like you've got a good hand for it. Wish I could offer more help/info but really I just understand the fundamentals of it all, nowhere near competent enough to push progress for this besides being a guinea pig for tunes :D

[Ape Factory]

This is awesome. And I really agree/appreciate the cutting numbers out, threads get so quickly derailed by dickheads, on all forums, over the wrong thing.

Catless DP argument for carbon makes a lot of sense. Wonder what the pressure difference really is during the overlap that allows backflow, because it seems 7-10lb from the supercharged group doesn't solve CC. Not arguing that removing cats wouldn't remove at least/more pressure than that, cause I could see that being the case too.

Those are definitely some nice curves. I've got a b7 rs4, and I'd be interested in a nicely cleaned up N/A tune. Looks like you've got a good hand for it. Wish I could offer more help/info but really I just understand the fundamentals of it all, nowhere near competent enough to push progress for this besides being a guinea pig for tunes :D

You're not in San Antonio are you? Saw a blue RS4 going the other direction on Sunday.

[bendilzerian]

You're not in San Antonio are you? Saw a blue RS4 going the other direction on Sunday.

Nope I'm in Houston, but there's 2 other sprints in Austin as far as I know could have been one of them!

Sent from my LG-H810 using Audizine mobile app

[Ape Factory]

Ah too bad. Definitely had an aftermarket exhaust and I've not seen him at any of the local Audi Club meets or at cars and coffee.

[RS5ish]

I think I will follow this thread a while. I have the JHM tune and out of the tunes I have had on other cars these guys are the most hush hush about whats changed I have ever talked to. That being said the car runs a little better but not worth the price of admission in retrospect.

I am currently more interested in a Tiptronic tune than milking the engine anymore for now. Anyone got a lead on one of those?

[Ape Factory]

Not sure how I missed your post but I'm surprised you didn't think the tune was worth it. I noticed a pretty healthy gain and even recorded a 25 wheel hp gain on a dyno. I just completed a carbon clean and a full service on the transmission and differential and the car feels great.

We don't have the Tiptronic, but an S-Tronic. Why do you want a TCU tune? What is the OEM tune not doing for you? I find zero issue with the OEM TCU tune. Only reason you'd need one is if you're making more hp than the stage 1 JHM tune.

Edit: Also on the water/meth front, honestly, after doing a carbon clean myself, it ain't going to help. Fuel has far more "detergent" power than water meth and water/meth is only being sprayed at WOT. Not nearly enough to do any serious decontamination.

[Schoona]

Thread bump...

Latest thoughts on WMI on the CFSA/CFSB engines ?

carbon clean prevention/maintenance?
power?