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crushing Vs with my Wurm
2013 GT500 - 700+ HP
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Discussion Starter #1
Fellas,

I am ready to spring for the Maggie and am ready to go to Maryland to do it. It has been brought to my attention by a VERY reputable tuner that the Maggies are quite prone to 'heat soak', and this in turn is producing detonation and timing to be pulled. Have any of you had this problem and what are you doing to avoid it. Is anyone running 180' thermostat to solve? is anyone cool charging the inlet air to get better consistency? Does the StealthV tune make the maggie more consistant? I need to know as these affect my decision...

Advise


F
 

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Florian -

I've logged the Inlet Air Temps while tuning and have recorded numbers as high as 160 degrees - usually more like 120 going down the highway (or less). Keep in mind - this measurement is made not at the MAF, as the Maggie kit relocates the IAT sensor to the base of the MagnaCharger. I believe it is measuring temperatures after compression, so 120 or so really wouldn't be that high. EDIT: Just checked logs - usually ~110 on the open road.

Does the StealthV tune make the Maggie more consistent? Good question. Rick's cooling strategy keeps my V running at 190 nearly always - where before it would easily hit 212 or higher in traffic, and run about 200 on the hiway. So, there is some help there. I know lawfive (I think) is running a 180 thermo - he might chime in here.

Lastly, cooling the intake charge is something I'm working on now. I in fact had hoped to have it done this week - but given the challenges of running a small business and the new noise the Maggie is making, it will be a while. My thought is a small (25-50) dry shot inside the Volant CAI - similar to what we've seen posted before. Only difference is I'm hoping to have the PCM trigger the nitrous :canttalk:

Alternatively, I've heard very good results from those using the snow performance boost cooler. Magnuson doesn't like what the mist might be doing to the rotors - but it sounds like it works quite well. Easier to setup? Not sure...but probably cheaper to own in terms of fluid refill (you do it yourself) vs. nitrous recharge. Initial expense is less also (~$600)

You are correct, though. The Maggie by design is prone to heatsoak. The I/C works pretty well. I'd be curious to know what A&A or others like Elridge do to the I/C to improve the performance. I've heard that they do something, but I don't know what.

Good luck.

WW

P.S. - a serious point to consider - you can get a lot of the power of the Maggie (in stock boost form) from heads, cam, headers and a tune...but you've already thought of this I'm sure. You can also get nearly ALL of the power, if not more, from a simple wet system :D
 

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crushing Vs with my Wurm
2013 GT500 - 700+ HP
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Discussion Starter #3
Bill,

Thanks for your .02 You bring up some good talking points...hopefully others will step up here and divulge.


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2009 Z06 / 2013 F150 EcoBeast / 2008 Twin-Turbo Bimmer
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Comparing intake air temps on a N/A V to one with a Maggie is like :eek:

From the PCM perspective, it monitors the IAT vs. the cylinder air charge. The higher the IAT and engine load, the more timing is reduced. Maggie's stock will start to pull timing at 131 degrees of IAT which is quite easy to attain in stoplight to stoplight runs, high ambient temperatures, track days, etc.

Keeping the intake air charge as cool as possible through lower thermostats, better I/C efficiency strategies, cooling fan settings, etc. will help. An aftermarket calibration, whether Stealth or others will certainly be an advantage and may provide additional strategies to help combat the problem.
 

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Adding a product like water wetter to the intercooler fluid should also help.
 

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Nitrous works great except when its empty, and that is fairly often. The maggie is always there,, and ready.:lildevil: Its the out of the hole power that is fun. My experiance with heads is that not much is gained off idle. Some of the south west guys should chime in on the heat soak. I havent had a problem with that yet.
 

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2005 Stealth Gray CTS-V, 2009 Black CTS-V
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Florian said:
Fellas,
I am ready to spring for the Maggie and am ready to go to Maryland to do it. It has been brought to my attention by a VERY reputable tuner that the Maggies are quite prone to 'heat soak', and this in turn is producing detonation and timing to be pulled. Have any of you had this problem and what are you doing to avoid it. Is anyone running 180' thermostat to solve? is anyone cool charging the inlet air to get better consistency? Does the StealthV tune make the maggie more consistant? I need to know as these affect my decision...
Advise
F
I would definitely agree that the Maggie can be prone to heak soak. I experienced varying dyno runs, knock when the car got hot (i.e. I'm roaring down the freeway, lots of on and off WOT, for many miles, etc.), timing pulled, I think it even was messing with the air/fuel ratios (but that I'm not an expert on that), etc., the whole nine years...

In my case, however, a huge part of that was heavily related to the fact that, for reasons that baffle me, my intercooler was drastically low on fluid. Since that has been filled, the car has performed MUCH more consistently.

I don't have a tune that reduces the operating temp of my car down a few degrees. I don't have a vented hood, nor a 180* thermostat. As a result, yes, the motor definitely can get a little warm :)lildevil: ), but, in my opinion, it isn't anything too egregious. When I had my 1970 Z28 Camaro (this had a nice, mid-range 383), the "old" carb was malfunctioning and would literally dump fuel down one of the venturis. I couldn't figure out why on earth the underhood temps were SO DAMN HIGH (it would vapor lock the car in not too hot weather). I even went so far as to wrap the headers, which worked beautifully until I discovered it was the carb causing the problem the entire time. Why do I bring up this seemingly worthless anecdote? Just for a little perspective---the under hood temp with my '70 was much, much higher than what I am getting from the V with a maggie.

In my mind, once everything is dialed in, pulling a few degrees of timing out to help prevent detonation just isn't that big a deal. And I like to believe that losing a little HP is much better then blowing a motor, which is what detonation likes to do (I'm extremely sensative to detonation...)

In any case, one possible solution to consider if you are shooting for the max timing possible is to add a little Torco to your tank at each fill up. This stuff works wonderfully, but that is an answer that many don't feel comfortable with for various reasons. But it works very well in reducing/eliminating knock--and you wouldn't have to use a full can by any stretch of the imagination if you don't go crazy with the timing...
 

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So is the relocated IAT sensor pre- or post- intercooler?

LPE and Mallett and I *think* Andy do not relocate the IAT sensor... any ideas why?
 

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Dreamin -

The IAT is mounted IN the intercooler base below the huffer, near the MAP sensor.

WW

(With some tuning changes one could easily run the IAT off the MAF - unless you're going MAFLess like me :devil: )
 

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Several months ago Hot Rod Magazine did a Maggie in a GTO. There were heat soak problems, particularly at a dragstrip. In normal driving where the Maggie is not continously activated, heat soak is not so bad.
Hot Rod cured the problem and got consistent runs by adding on a nitrous system. I think it was a dry system.
 

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My read on this is that it's the heat soak from the heads heating the blower assy. more so than the intercooler itself. I'm not seeing "after" temps anything like what the heat soak temp grow to.

I have been concerned with the hose routing (and have changed direction of water flow from top to bottom) and the lack of controlled waterflow much like my Typhoon. Personnally I would rather see the waterflow controlled by IAT temps rather than continuous flow. I have adapted the IC pump to run on with fans and have still seen heat soak, leading me to believe the heat soak is not from the IC itself particlularly since we no longer have the plastic intake which in itself shouldn't transfer from heads.
 

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crushing Vs with my Wurm
2013 GT500 - 700+ HP
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Discussion Starter #13
seems like nitrous is the way to get around the heat soak, but I hate to get so complicated with the blower. Any other thoughts?


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Lemon Law'd '05 V
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I'm not speaking from experience with a Maggie, so forgive me if this sounds out of line. I don't think the high IATs can be effectively dealt with by Engine Coolant Temps. Coming from a world of turbos, intercoolers that were more efficient made a much larger difference than ECTs. Sure, its good to keep the ECTs slightly lower than stock...my V N/A runs over 200degs in the summer...up to 230 before it comes down with fans. But on a F/I motor, the intake temps are much more important.
A good friend who autoxes a modded WRX (+400hp) put a small racing gas tank in his trunk filled with water and ice. He ran tubes, pumped by a boat bilge-pump, to a slim-line cooler (oil-cooler) mounted ON TOP of his stock intercooler. This allowed him to run the car as aggressive as it could...granted for 5-8 one-minute runs in a day...no heat soak, no detonation, very aggressive timing and boost.

Now I know there's no room for the extra cooler under the blower, but what about the air-to-water element? Or a sprayer? Make that fluid cooler, and it would make a big difference.

Another idea, another Subie lunatic mounted a propane system to increase octane and lower intake temps. This worked very well for him.

But as Elridge had eluded, making the Maggie intercooler more efficient is a good idea...that's the better road.

-ace
 

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I'm not seeing high temps while running, only after you shut it off. The hot side radiator is huge and, with my IR themometer, never gets hot. After 1/4 tank of gas in 20 minutes on the track (so I've had some WFO time) the discharge water from the manifold I wouldn't consider it to be overly hot.

so I don't see how making it more efficient is going to help. I think it needs a better insulated manifold from the heads. When you shut off the engine it is normal for the heads to superheat the stagnant block water.
 

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Here's some data from a 23 minute "city driving" log collected back in April of 2005 on a Maggied V.

Mean RPM = 2184 (max of 6609)
Mean MPH = 35 (max of 83)
Mean TPS = 13.92%
Mean ECT = 197 *F (min of 187, max of 208)
Mean IAT = 136 *F (min of 75, max of 153)

In this example since IAT is above 131 *F, timing is being pulled a majority of the time in normal driving.
 

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Denniscars -

I'd agree the that the heat exchanger side of the intercooler is plenty efficient. Even when reading 160 degree IAT's, the outlet hose from the base of the maggie (intercooler) feels mildly warm. I haven't measured, but say about 100-110 degrees?

Wonder what A&A is doing to modify things...internal to the base of the intercooler maybe? Slower coolant flow? :yup: Maybe just a voltage reduction to the maggie pump motor?

BTW - how did you end up doing the i/c pump run-on circuit?

WW
 

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I think your moving so much flaming wind that it doesn't have much chance (time) to transfer in the WFO throttle position. It does pull the temps down nicely particularly above say 40 mph (that's 64.373 76 kilometer/hour for our friends to the North). If I take it out from the cool garage first trip the temps are moderate and only fluctuate during full boost and quickly come down. If I shut the car down for any length the IAT temp immediately climbs and will come down after some time after the coolant temp recovers. I would also like to have some type of engine coolant recirculation run on to keep the heads cool which will in turn keep the aluminum intake from conducting head heat. After all aluminum to aluminum conducts very well.

My Typhoon transfer pump comes on at a certain engine coolant temp, which I think may be a little late, but hopefully I'm not flogging it until it's up to temp.

I put an aux relay that runs the IC pump as long as the run on fans run. I hid it in the forward fuse box. I doesn't seem to pull the temps down after you shut the motor down like I would have thought. That's why I still think it's conductive heat. But somebody still may call BS.

I also think Mag is flowing too much water too fast. Any old timer knows what happens when you thought you had a hot car and wrongly think to take out the thermostat altogether. Which is also another reason I don't prescribe to 180 thermostat.
 
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