[iqraceworks]

I’ve been running the V5 Stage 2+ E40 tune since late last year when I upgraded my LPFP to the Walbro 450. Everyone says it’s the most powerful tune that MHD has….and it sure feels pretty stout.

Recently, I decided to fill up with an E50 fuel mix, and try the newest V9 E50 tune….it’s got to be better than the V5 E40 tune…right? More ethanol content, and 4 revisions of changes should be making more power…right?

Right after flashing the V9 tune, the first thing I noticed right off the bat just driving around was that the tune seems pretty “soft”……and you can see why when you look at the two 3rd gear pulls that I logged (RED is the V5 E40 tune, BLUE is the V9 E50 tune) on virtual dyno. I’m not sure if the HP/TQ numbers are accurate, but it’s a good way to compare multiple tunes. Corrections are being made for the different intake temps. (see difference below)

1. TQ/HP Curves: The V9 tune gives up a massive amount of HP/TQ under 3,700rpms. Close to 80ft/lbs and 50hp difference at 2,700rpms (if you trust virtual dyno to be correct). The V9 E50 tune does seem to make a little more TQ/HP above 3,800rpms though….maybe handy if you are roll racing? For a street car, all that grunt downlow from the V5 E40 tune really comes in handy, and you can really feel it when you are driving around. It would be nice to get a ¼ mile draggy run from each tune to see if the low end grunt of the V5 tune would be faster than the extra top end over of the V9 tune?

2. Boost Targets: The V9 tune only targets 18psi boost on the upper end, while the V5 tune targets close to 21psi. Especially in the lower RPMs, the V5 really puts the boost to the motor. I’m sure that’s the main reason why it’s got so much more grunt downlow vs. the V9 tune. I’m not sure why MHD pulled so much boost out of the V9 tune considering the higher ethanol content the tune was designed for.

3. Fueling: The V9 tune starts out richer than the V5 tune, and then they swap at around 4,000rpms and the V9 tune gets leaner than the V5. I got a couple of small timing corrections with the V5 E40 tune during shifts (which I’ve heard is normal), but with the V9 E50 tune…..during the pull there were up to -5 degrees of timing corrections, which seems like a lot to me. I’m guessing the leaner fueling was the cause of that? The slightly leaner fueling could be why the V9 picked up some more power on the top end?

I was really hoping that after 4 more revisions, the newest V9 E50 tune would be something special……but to me it looks like MHD just traded big lower end power, for a little top end push. Who knows, maybe that might work better for some people. Hopefully here in a month or two I will be installing a set of RB Two turbos, and getting a custom tune….I’m curious how the logs will compare.

[TiAgAu]

Thanks for posting this Didn't expect that much difference in boost. Hows the timing look on the V9 E50 from like 4000rpm? Any higher than v5? or maybe it was cooler temps that made the power

Nice background btw

[_N54]

Time for a custom tune since you recently installed your inlets

[iqraceworks]

Originally Posted by 6266N54

Time for a custom tune since you recently installed your inlets

Yeah......and the RB turbos are going on soon, so there's that. I'm hoping to see a pretty big jump in power.

[_N54]

Originally Posted by iqraceworks

Yeah......and the RB turbos are going on soon, so there's that. I'm hoping to see a pretty big jump in power.

You will If I had to go with twins I would def be buying RB's.

[iqraceworks]

Originally Posted by ARandomNickname

To be honest, you can't really compare these 2 tunes as V5 has desensitized knock sensors (that's why you see more timing pulls in V9 as V5 hides the knock) and runs more boost than the stock turbo's are safely handle in the long run.

V9 should always be the tune of choice for daily drivers. It has a more sofisticated load based tuning method.

You are making a lot of assumptions there. Feel free to post up some facts.

I can tell you for sure that the V9 tune feels weak compared to the V5 tune...even at low boost levels. But hey, if you want to run it...go for it

As far as how much boost the stock turbos can "safely" handle......pushing them with any more boost than stock levels is a gamble.

But from seeing all of your other posts on here...you are the expert, not me

[Saif2018]

Originally Posted by ARandomNickname

To be honest, you can't really compare these 2 tunes as V5 has desensitized knock sensors (that's why you see more timing pulls in V9 as V5 hides the knock) and runs more boost than the stock turbo's are safely handle in the long run.

V9 should always be the tune of choice for daily drivers. It has a more sofisticated load based tuning method.

V9 feels weak compared to v7.1, takes a while to build boost, personally prefer v7.1

MHD said V5 is safe, although probably safer to run maps which don't have desensitised knock tables.

[Saif2018]

Originally Posted by iqraceworks

You are making a lot of assumptions there. Feel free to post up some facts.

I can tell you for sure that the V9 tune feels weak compared to the V5 tune...even at low boost levels. But hey, if you want to run it...go for it

As far as how much boost the stock turbos can "safely" handle......pushing them with any more boost than stock levels is a gamble.

But from seeing all of your other posts on here...you are the expert, not me

Expert lol,

Pushing them more than 18psi has a significant decrease in longevity from what I read,

Unless someone has some hard data, will be difficult to say how long they last.

[iqraceworks]

I'm sure it's not good on them to push them hard....but the goal of a tune is hp gains, not turbo life 😁 not sure if I would really worry about 2-3 psi when you are already pushing them hard. If there was a tune that would push them to 25psi....I would probably try it 😂 (with 3.5 tmap of coarse).

If the goal is turbo life....just leave everything stock.

[Saif2018]

Originally Posted by iqraceworks

I'm sure it's not good on them to push them hard....but the goal of a tune is hp gains, not turbo life 😁 not sure if I would really worry about 2-3 psi when you are already pushing them hard. If there was a tune that would push them to 25psi....I would probably try it 😂 (with 3.5 tmap of coarse).

If the goal is turbo life....just leave everything stock.

lol,

Yeah that's True, turbo's eventually gonna fail, plus if you good for stage 2 turbos then it doesn't matter anyway.

[dpaul]

Originally Posted by Saif2018

Expert lol,

Pushing them more than 18psi has a significant decrease in longevity from what I read,

Unless someone has some hard data, will be difficult to say how long they last.

Another possibly relevant issue in MHD's decision to lower boost target is the specified range of the stock TMAP sensor, nominally 21 psi. Measurements are likely less accurate at the top of the range and transient excursions above 21 psi will not be detected.

[Bimmer_Bro]

Originally Posted by dpaul

Another possibly relevant issue in MHD's decision to lower boost target is the specified range of the stock TMAP sensor, nominally 21 psi. Measurements are likely less accurate at the top of the range and transient excursions above 21 psi will not be detected.

This is true. I Remember Terry from BMS said you want 2 psi of head room with that sensor. So if 21 is the limit, you shouldn't be running more than 19psi.

[iqraceworks]

Correct me if I'm wrong, but I thought the oem N54 sensor was a 2.5 bar sensor (36psi). Is that not correct?

I know that on a few of my logs with the V5 E40 tune, I've hit 21.2 peak boost....so I know it reads at least that much.....the tune actually targets 21.4 but my turbos can't hit that. And honestly, I've never seen or read about anyone having issues with that V5 E40 tune.... everyone really loves it since it makes big power for an OTS tune.

[theobjectivist]

Originally Posted by iqraceworks

Correct me if I'm wrong, but I thought the oem N54 sensor was a 2.5 bar sensor (36psi). Is that not correct?

I know that on a few of my logs with the V5 E40 tune, I've hit 21.2 peak boost....so I know it reads at least that much.....the tune actually targets 21.4 but my turbos can't hit that. And honestly, I've never seen or read about anyone having issues with that V5 E40 tune.... everyone really loves it since it makes big power for an OTS tune.

My stock sensor (on an e60) fails on 21psi triggering the 3100 code. In order to target the 22-24 psi I wanted, I had to upgrade to the 3.5bar sensor.

If youre upgrading to the RB 2s, i assume youre going for bigger power, so be ready with the new sensor so your tuner can accommodate

[dpaul]

Originally Posted by iqraceworks

Correct me if I'm wrong, but I thought the oem N54 sensor was a 2.5 bar sensor (36psi). Is that not correct?

I know that on a few of my logs with the V5 E40 tune, I've hit 21.2 peak boost....so I know it reads at least that much.....the tune actually targets 21.4 but my turbos can't hit that. And honestly, I've never seen or read about anyone having issues with that V5 E40 tune.... everyone really loves it since it makes big power for an OTS tune.

36 - 14.7 (at sea level) = 21.3

Really, you cannot rule on whether you are hitting 21.4 or not. At that point, if not sooner, you are beyond the range of your sensor

[iqraceworks]

Yeah...I have a 3.5bar tmap and adapter from BMS sitting in the shop in case I need it.

The tuner I've been talking to told me that he should be able to hit 500-ish hp on 20psi or so with the RB TWO's and an E40 fuel mix. He said if possible, it's better to use the oem tmap unless you absolutely have to run the 3.5 tmap since the 3.5bar tmap isn't as "stable" until you get up over 21-22psi. So at this point....we"ll see how much boost he can dial in with before the stock HPFP can't keep up.

[iqraceworks]

Originally Posted by dpaul

36 - 14.7 (at sea level) = 21.3

Really, you cannot rule on whether you are hitting 21.4 or not. At that point, if not sooner, you are beyond the range of your sensor

Good point. I think at this point since it's running so great on the V5 E40 map....I'm going to keep running it!!

[Silent9n54]

Originally Posted by iqraceworks

Correct me if I'm wrong, but I thought the oem N54 sensor was a 2.5 bar sensor (36psi). Is that not correct?

I know that on a few of my logs with the V5 E40 tune, I've hit 21.2 peak boost....so I know it reads at least that much.....the tune actually targets 21.4 but my turbos can't hit that. And honestly, I've never seen or read about anyone having issues with that V5 E40 tune.... everyone really loves it since it makes big power for an OTS tune.

You easily hit 22 psi with V5 E40 map with 3.5 bar sensor

few of my friends are running it with 3.5 bar sensors, seen as high as 22.3

[iqraceworks]

Originally Posted by Silent11N54

You easily hit 22 psi with V5 E40 map with 3.5 bar sensor

few of my friends are running it with 3.5 bar sensors, seen as high as 22.3

And I bet they love that map don't they?.

[ragingpanda]

When I had stock turbos, I only ran v5 e40 map until I got a custom tune. You will definitely need the 3.5 tmap sensor when you upgrade turbos.

[iqraceworks]

Originally Posted by ragingpanda

When I had stock turbos, I only ran v5 e40 map until I got a custom tune. You will definitely need the 3.5 tmap sensor when you upgrade turbos.

Yep, got one with the adapter from BMS....just sitting in the box until I get my new RB's on the car.

[gster109]

Originally Posted by ARandomNickname

To be honest, you can't really compare these 2 tunes as V5 has desensitized knock sensors (that's why you see more timing pulls in V9 as V5 hides the knock) and runs more boost than the stock turbo's are safely handle in the long run.

V9 should always be the tune of choice for daily drivers. It has a more sofisticated load based tuning method.

Could you elaborate on this? I feel like v7 91octane stage 2 vs the v9 is much more daily drivable. V9 comes on very aggressively all at once as where v7 feels much more smooth and linear.

I'm not understanding what you mean by load based tuning ? Do you mean the car will stay out of boost more while just cruising like WGDC?

Do you use linear throttle mapping?