L99 Magnuson Heartbeat S/C Kit Advice

So i'm working on tuning a '15 Camaro L99 A6 car with a Magnuson Heartbeat S/C kit. The supplied Maggie tune seems SUPER soft, hardly any timing with not even a hint of KR on any pull. Shift points are entirely stock at 5900, no changes to the trans section over stock at all.

I was able to determine that I could add about 5 degree timing safely, which pulled up the power nicely.

I want to move the shift points up a couple hundred RPM, but not sure if that's a good idea on the L99 with the DOD springs and already having 6psi of boost acting on the valve heads, worried about valve float/damage there.

Trans wise, any ideas on how much HP the A6 can handle? I would love to go in and set it up to have a little bite on the shifts like I do my N/A guys, but worried perhaps it's being pushed as-is. This kit is rated at 600 hp engine (obviously best case scenario at sea level), by the numbers it's making around 560-80ish at my location.

Seems to run pretty solid, but looking for any advice on boost tuning with the L99/A6 setup this car has.

Thanks!

The tunes from Magnuson have to be 50 state legal. And--a lot of guys do their own install and then go out and beat on the car without checking anything in the tune. If the tune was set up close to max power, those guys would blow up their engines and then call Magnuson wanting a new engine installed for free. If you have a 6L80, it will hold a bunch of power if it is tuned correctly. Just don't turn off all of the torque protection if you want it to live. If that 15 Camaro is a DI engine, it can take a few more degrees of timing than a non DI motor. My non DI max timing at boost is 18 degrees. I know of a few guys that run 22--23 degrees in a DI/blower setup. It takes good gas though.

Thank You. I'm very close then as I have it taking 18 degrees with no KR at this point on 91 pump, with having to start pulling 1-2 degrees above 100 degrees post blower IAT. 2015 still uses the non DI 6.2L, and this kit really seems to push the stock fuel pump to the brink. Looks like they up the maximum fuel pump DC to 100% from 90%. The car runs a static fuel pressure of 55, and by the shift point it's a good 5-8psi down. The ZL1 of this era has a different fuel pump, and most say the stock SS pump will support 520ish crank on boost applications, which I certainly believe. I'm willing to bet the actual AFR is getting in the 12:1 range above 4k looking at the data.

It's a good kit, love the potential this setup has for sure. Would be nice to see a larger intercooler reservoir as well, the IAT's hold solid from a dig until about 3rd gear, then by the end of the 1/4 I have about a 15 degree temp rise, you can really see when the system starts to get heat saturated during a pull. However, it fully recovers immediately after with little to no soak that I can see.

Thank you for the advice on the trans section, it shifts great and has full TM and stock settings, i'll leave that be. Happy to see i'm right in the realm of where I should be, and I really appreciate the advice!

Are you saying you are tuning your blower engine with no wideband? The fuel pressure needs to be steady also. What is your injector duty?

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Originally Posted by Lakegoat

Are you saying you are tuning your blower engine with no wideband? The fuel pressure needs to be steady also. What is your injector duty?

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Correct. No changes made to the fueling section (supplied tune). Magnuson increased the timing on their 2nd revision (they use HP Tuners RTD Tool) by 2 degrees right out of the gate. I ended out 2 degrees above that, rest of the tune is as-supplied.

I agree on the fuel PSI, should hold 55 the entire time, however it is my belief that the stock fuel pump is being pushed too far straight away as even with the supplied Magnuson tune the fuel PSI will not hold in the upper R's.

The Lingenfelter kit (same magnuson kit) even states they change out the pump, the Whipple kit comes with a Zl1 pump. Nothing against this kit, it works, but I think it's pushing the stock pump too far. It appears to me there is an attempt to compensate for this shortcoming in the upper R's by commanding a richer and richer AFR (to compensate for lower fuel pressure = command richer lambda and injector DC). It's in the 9:1 range (supplied Maggie tune) by 5900. In the tune, that's not cat protection either as the max cat protection lambda is well above that afr.

On 4.5-5.5 psi I am seeing at this altitude, that's not really playing with fire enough to hurt anything as long as it's in the mid/high 11's AFR and conservative timing and not doing 1/2 mile or longer pulls. However, any mods even such as a K&N filter would probably up the boost just enough to really push the thing into areas I would be uncomfortable with fueling wise.

Again, it's a good kit, I love it compared to some I have installed and the power is great for what it is, but I think adding just a pump booster into the mix would make it a perfect kit right out of the gate and give some headroom for light mods such as headers/exhaust.

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Originally Posted by Lakegoat

Are you saying you are tuning your blower engine with no wideband? The fuel pressure needs to be steady also. What is your injector duty?

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So my suspicions were correct. Installed my wideband, the AFR was pretty solid in the mid 11's. All they are doing is following the fuel pressure decline with richer targeted lambda. It works, in my opinion it's not correct, but works. Fuel pressure starts at 57 and is at 38psi by 5900 RPM.

I then added a set of longtubes, K&N Filter and a JMS Fuel Max pump booster.

Locked the AFR in at 11.8 through the range. Fuel pressure is solid at 53-55 psi through the run with the JMS box set to 1/2 it's available range (around 2V increase). Lost about 1lb of boost, so obviously the cats and factory mid pipe were are restriction.

Car runs pretty solid. Getting about 20 degrees timing on 91 pump in 90 degree ambient. The next issue will be the heat rise post blower, the intercooler tank is super tiny and by the start of 3rd gear the IAT really starts to take off vs holding solid from the hit until that point, you can see when the intercooler reserve starts to run out. A nice 1 gallon or so tank would be very beneficial I think. All in all, the kit is pretty solid and the fit/finish is awesome. Not even pushing the blower at all......which I like.

Would love to pulley down and run 6-8 psi, but i'm fearful of the stock L99's weak springs and possible valve float. The next addition should be a nice cam/spring/pushrod combo to really start to utilize this setup.

You are not going to affect the springs with 8psi.

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Originally Posted by Lakegoat

You are not going to affect the springs with 8psi.

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Interesting, thank you for that! Honestly I have never confirmed that, just always assumed the L99 cars were pretty weak spring wise and didn't want to risk anything. I think moving up to 8 or 9 psi would be a great improvement if the rest of the powertrain can take it safely.

Can you read the RTD tune Magnuson gives you and edit it with VCM editor and reupload with the MPVI2? If not modify, can I view it with MPVI2 or even the RTD?

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Originally Posted by Bigg Tim

Can you read the RTD tune Magnuson gives you and edit it with VCM editor and reupload with the MPVI2? If not modify, can I view it with MPVI2 or even the RTD?

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You will not be able to do anything with the supplied RTD file except use the RTD program to load it onto the vehicle. From there, inused the MPVI2 to read out the vehicle and make my changes.

However, I know on newer Fords they are using custom OS's with the RTD setup, that the MPVI2 will not recognize as they are specific to that shop/tuner, therefore you cannot read out the vehicle in those instances.

That was not the case yet on this setup fortunately.

Thanks for the info. I ended up sending magnusson my stock file and they built one off that and I used my mpvi2 to load it. I am able to modify that tune but I have not. The RTD was never used.

Stupid question perhaps, but why didn't you just change the fuel pressure in the fpcm? They lower pressure in the higher rpms from factory...

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Originally Posted by GHuggins

Stupid question perhaps, but why didn't you just change the fuel pressure in the fpcm? They lower pressure in the higher rpms from factory...

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On the original Magnuson tune, they did alter the max DC that could be requested in the FPCM from 90% to 100%, but that was the only changed to the FPCM programming that I can see.

As you can see in this log, I was into the 30psi range on the fuel pressure with it falling as the RPM climbed:

https://drive.google.com/open?id=1sN...0lFJ2kmEbmUUFR

My research indicated that the stock fuel pump is pretty much tapped out at this power level. I did also note the Whipple kit for these cars comes with a ZL1 pump, and claims nearly the same HP as the Magnuson.

The only changes in the FPCM from Magnuson, effectively letting the FPCM command 100% and run the stock pump as hard as possible to support the needed fuel flow:

https://drive.google.com/open?id=1sY...g06k6C08pUH6Y4

Lastly, here's a log when the car was 100% stock, and the fuel pressure remains rock solid at 54 PSI throughout a pull:

https://drive.google.com/open?id=1dC...ews1hqJxuR__J2

I'm getting ready to do a Whipple kit on a 2014 here soon, it will be interesting to see the results! I also have dropped this Magnuson kit 1 pulley size, and going down 1 more here soon as well to get it leveled around 6-7 psi at my altitude. Car runs pretty good and both the owner and I are very happy with the results after the tune was adjusted/fuel delivery brought up to speed.

You have to read the fpcm to get the actual tables to adjust... Still shouldn't be dropping to 30psi, but if the booster worked then the fpcm should have made some difference...

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Originally Posted by GHuggins

You have to read the fpcm to get the actual tables to adjust... Still shouldn't be dropping to 30psi, but if the booster worked then the fpcm should have made some difference...

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Correct. I had the sub window in the way, but here you can see I have read out the FPCM as well:

https://drive.google.com/file/d/19sr...ew?usp=sharing

The supplied tune from Magnuson adjusted no tables other than the one denoted.

The pump type lists as fixed on this setup with a target pressure of 58 across the board? It was able to maintain before the blower as seen in the screen shots of the pre-install diagnostic logs.

Lingenfelter installs a pump booster with this kit on their builds, which in conjunction with my findings of what the stock pump is capable of, as well as Whipple supplying a ZL1 pump with their kit (which I consider more appropriate), shows me the stock pump is at it's limit.

I put an SLP supercharger on Wife's camaro L99 a few years ago. Also had pressure in the low 30's. Definitely need to upgrade to a ZL1 pump and change the FPCM settings to match those from a ZL1. A solid 65 psi @ wot and makes a huge difference in power/performance with better atomization. It's worth it...........

Agreed.

It runs very solid now, i'm pretty happy with the results after the fuel pressure correction and tune rework/1 pulley down after adding longtubes/mid pipe. Traction is certainly an issue!

The stock pump works fine if you have a MSD BAP, holds steady 58psi all the way to 6800rpm on a LS3 Whippple, 10psi, headers after setting 58psi in the FSCM at the higher fuel flow rates. With stock FSCM settings, even if you have a boost a pump, fuel pressure will still fall but it's not because of the pump, it's because of the programming. Stock pump with correct FSCM programming you will lose pressure without the BAP.

I was also down to about 30psi at WOT above 4500rpm but I didnt notice a power change after programming the FSCM and getting it back up to 58psi. My AFR's were also rock solid the entire time since the ECU adapts PW to match fuel pressure. My IDC did drop at least 20% though, down from 100-110% at 30psi to around 80% at 58psi. Now I know I can run my injectors to 100% with good results!! :)

The engine ECU says fixed, that is because it uses a FSCM to control the pump. It's PWM from the FSCM no doubt. Why they reduce the pressure at the higher fuel flow rates, nobody knows but yes, as Greg says that is the first step in fixing things.

If you don't already have a BAP, then swapping to a ZL1 pump is best, the BAP is just more stuff to go wrong and it makes radio interference! Stations don't come in as clear when your far away from towers. It's probably cheaper to have a ZL1 pump than a BAP is my guess?

Well you guys were absolutely correct!

I am sorry for not getting back to this thread sooner, it has been very busy! I now see what you are talking about with pressure drop after reading out and studying the FPCM tables. On an N/A vehicle, being as pressure request is based from desired fuel flow rate, the table is at 58 psi in stock form/flow. Add in a blower though, and sure enough it follows that table out more which drops pressure.

I just did a Whipple kit a 5th gen as well, interestingly enough they provide a pump booster, AND the PE is set flat in the tune, which confirms my findings on the Heartbeat kit that to maintain AFR they simply rape the PE table to get the desired AFR around the falling fuel pump pressure.

Whipple does not modify the FPCM settings either.

However, when I did my final tune on this one, I did. Works like a champ! Thanks for the info!