MatthewJ

Since our ECU mapping is load based, could the increase in boost be from the 30* difference in ambient temp? I see more stable boost numbers when its hot vs cold. Cold weather it will spike and then try to back off the boost since the air is denser.
Does the car feel any different after driving with it?

GuardianVA

20*C is actually much more ideal for boost and performance, all other factors being equal. 32*C is getting on the warm side of things. Notice the initial timing on the colder run (stock) vs the warmer run? The timing target is indexed to IAT for it's initial targeted timing curve, so it starts with more timing advance and stays at a higher timing advance through the whole run. I can't say the better matching of actual boost vs target is just from the intake, as there are other factors that I can't see in the log (namely AFR). Most intakes cause a leaner run condition, which is where their power comes from, especially on untuned naturally aspirated cars, but also on turbo vehicles. I'd be curious to see if their is any adaptation by the ECU after a good 4 to 5 100% load runs. It may be running a little leaner than when stock, but the ECU may start to dial in more fuel.

The reason you see unstable boost in colder whether is probably because the conditions are actually cold, as in at or below freezing. There tend to be diminishing power returns once you get down to 0*C and below, because the timing and fuel adaptation having limits, and the only other way for the ECU to stay inside its set load targets is to reduce boost.

xX G Xx, have you had logs on the stock air box where the boost consistently is not reaching the target like in the log you posted? If so, It's probably your Weistec BOV. They are venting to atmosphere, so you likely getting an fuel dump after each shift. It goes richer than target, and its holding down boost. Any logs with AFR shown?

xX G Xx

OK, I would think 20C/68F is not that cold to see that much of a boost curve difference.

Anyways, had a chance to drive in 30min of traffic this morning. (Weather around 30C/86F) I noticed the IAT was 5-10F higher than usual @ 120-135F and got there faster than usual. Popped the hood once I got into work. Holy F* the box is hot!! The manufacturer told me the box is just metal plus some type of taflon coating. Anyways, it does not deflect heat. I felt the inside of the box and it was also very hot. The entire engine is hot. Just the location of the stock intake is really not ideal. Right in the middle of the hottest part of the engine compartment. Not sure how well the stock airbox deflects heat and if Benz/AMG put any engineering into the material used & design of the box to battle heat.

At least when the car is moving, you will get some fresh ambient air to the cone filter. I don't see much change in IAT compare to stock box when the car is moving.

So, what I think:

When sitting in traffic, this intake system is probably not better than stock. It will soak up the engine compartment heat immediately. Stock system maybe has a better heat deflecting design? That plastic does look like it can handle heat. But at the end, it will get completely heat soaked as well.

When you step on it, just the shear increase size of the intake cone will get you more air to the turbos than stock or K&N/BSM inserts. Especially if you are tuned. I thought that was what I was seeing with the improved boost curve on the log. I have heard from the BMS intake guys that their boost curve also improved.

If you are really worried about heat soaking in hot weather traffic, then stick with the stock box and just get some K&N or BSM inserts. If you must have an aftermarket, higher flow, intake system, you now can choose between BMS or MST~



When you say "target", are you refering the the "target" on the log? The "target" on the log is at flat 0, since these were on JB4's Map 0 runs with no target boost. Just the ECU tune.

The purple line that you are seeing is the fuel trims. All low in the 20's.

No, I don't have AFR readings on my JB4. It's a known issue for some cars according to BMS. They will fix it one day... lol...

xX G Xx

Hope you can do a more complete test/review, Dan.

I should of Dragy and log the hell out of the stock box just a day before the install. I got too eager...

Dieseldan9

iTrader: (1)

My intake has shipped!!

All the pre orders look to be going out this week.

GuardianVA

I think you are misreading the logs then. That line isn't trim, it's boost target. Notice that it follows the lift-throttle spikes for boost. Trims would go up on the runs, not taper down like you see in the log. And on most of the JB4 logs I've seen with the C43, the trims are above 30 under full load. I could be wrong, but I'm reasonably certain that if you post the csv file, and look at it it will show you that that line is target. Just because the JB4 is on 0, it is still reading the CAN data for logging, including whatever the tune is telling the ECU to target for boost.

MarcusDubya77

Right there with ya!!

xX G Xx

Ya, I doubled check. If I'm target 5 psi from the JB4, it will show on the target column. Map 0 shows 0 since I'm not asking JB4 for boost.

Here's a screen capture of same MST log. Since it's long I have had to cut off. You can't see the column headings, but I circled and noted it.

xX G Xx

Had some time to beat the car this morning. Make about a dozen 0-200km/h & 100-200km/h runs.

• Due to previous dragy runs was in different density altitude, I really can't compare. But if the DA correction from my pal Henry is correct, then I really saw no gains or loss. Hope someone can do better Dragy comparisons. I botched it here being too eager to install. Too lazy to put back stock and test again. I will probably need to wait till year end to get similar DA as previous best runs.

• Previously I said the metal box heat soaks very fast in sitting traffic. I also found this morning that it dissipate heat. Immediately after the dozen WOT, high speed runs, I pulled over and open the hood. The engine is freaking hot, but to my surprise, the metal box was not. Cool to the touch. So, the stock cold/ram air snorkle worked really well with the system. The box material & special coating seem to both absorb and dissipate heat. Double edge sword... To actually get the cold/ram air to effective level, you probably needs to be going at 60mph....

xX G Xx

Dan, can you check simple heat temp of the stock air box before installing the MST? I wonder if the stock box also heat soaks completely in heavy traffic. I'm pretty sure the stock box get extremely hot on the outside as well, but how about the inside? You can take off the cover and just feel the inside for difference. Thanks man!!

The MST box basically soaks up all the engine heat when the ram/cold air is not flowing. I would feel better if the stock system is the same...

GuardianVA

Then I stand corrected. I was wrong. Still, seems so odd to see the boost curve change that dramatically, given the higher temps and lower timing advance with the MST run. Lower pressure drop before the turbo will increase its efficiency, but ~20% difference in PSI is pretty impressive.

I've been watching this thread, because I liked the filter design (conical and dry-element), as it's all around more efficient. Like what I'm seeing so far, now I'm curious if the results are long-term and consistent as more people get them.

Dieseldan9

iTrader: (1)

I plan 2 but still working on securing a jb4 but I think I finally got one.


Like I said I will do a full write up with install and results when I get the kit.

evoi19

Just to throw an idea out there, but maybe adding some thermo tec or heat deflecting material would help?

xX G Xx

So I was able to make some better Dragy runs this morning. For reference against previous best runs. Tune and gas are the same in these runs. Only thing different are the temp/DA & the intake.

** 4/12/2019 with Temp @ 23*C / DA: 1400 / MST CAI

0-60mph: 3.80
1/4 mile: 11.75 @ 118.99 mph
100-200km/h: 8.97


** 1/28/2019 with Temp @ 15*C / DA: 500 range if I remember correctly / K&N inserts

0-60mph: 3.63
1/4 mile: 11.67 @ 119.32 mph
100-200km/h: 8.93

Lazz83

This should have been handled in the research and development phase by MST! Bringing a product to market that does not meet all criteria of said application is just wrong. They should have done more research and used a better material besides metal to enclose the filter. I also read a lot about board members love for dry filters, surprise they are not as good as oiled filters (proven fact)- oiled filters cause no harm when prepped from the factory, now cleaning and re- oiling yourself may have issues or may not.

Terry from Burger was right in suggesting that this design & material would cause a heat issue.

I for one would never buy anything made in China, but to each his/her own

I can only hope is that AFE, AWE or another great CAI Manufacturer will design something well engineered for this car- that actually makes more power and increases airflow.

Here's an idea- why not just design higher flowing air boxes based off the stock air box that will accommodate large conical air filters, with larger inlet tubes to the intercooler??? Wait a minute I just might design my own in my CNC shop, stay tuned.

GuardianVA

I agree on the part about fleshing out heat and material issues in the R&D. However, you are just flat out wrong about your "proven fact" that dry filters aren't as good. Some dry filters aren't that good, but the Apexi designed filters (which this appears to be a copy of) are superior to oiled filters in both filtering AND performance. As far as filtration goes, dry is usually better in that respect in most applications. Sorry, but testing doesn't support your "proven fact."

http://mkiv.com/techarticles/filters_test/2/index.html
https://www.mishimoto.com/engineerin...d-air-filters/

MarcusDubya77

Oiled filters can also wreak havoc on MAF sensors or similar in the intake track. Those temperatures are pretty varied and the density is pretty far off too for those seperate runs. That is not conclusive enough to make a determination.

BMS

IIRC people were giving us grief when we chimed into this thread with some reasons why this would have the outcome it did

Anyways, the airboxes is only one part of the restriction in the setup. They have yet to actually come up with something better than stock IMO.

BMS

No MAF with this car, so no problem on that front. Plus oiled is usually better for fine particles, especially in turbo applications.
When it's a straight shot to the turbo, you definitely want it to filter as much as it can. lol

Lazz83

It was common knowledge & proven over the years that oiled filters outflow dry filters- perhaps you think K&N is just marketing hype, lots of data proving that their filters outflowed stock paper filters of the same error I did tests myself to prove it on Two AFE filters, one dry & one wet- Gee guess which filter won?? so yes it is also a proven fact by me. Maybe things have changed with dry air filters or are different in Australia but I doubt it- I never had great luck with dry filters in my experience & I've been installing CAI's for over 20yrs.

Oh and let me take a wild guess, Apexi sponsored that article that you linked?

I also agree that more testing must be done on this intake- it would make sense that increased airflow would make more power- so I am unclear on how the numbers came up short?

MarcusDubya77

I think it was, more or less, the fact that you are a competitor for a very tiny market. Seems a little odd to criticize designs when you are trying to sell your own setup, which has its own flaws. Besides, there are still no conclusive results. Those DAs and temps were completely different for the milliseconds in difference.

MarcusDubya77

Can you reference that? I would like to read the findings.

GuardianVA

Deleted.

GuardianVA

Deleted.

Dieseldan9

iTrader: (1)

Well only way is to have back to back runs with jb4 and see what the outcome is.

Hope I didn't jump the gun cause this damn thing will be for sale before u know it.

Already went through 2 tunes so I am used to it