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MPI timing removal vs. Head shim

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TurboM700

Well-known member
Nov 26, 2007
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St. Anthony MN
With that turbo at 14 lbs the shim is the way to go plus I'd think real hard about adding an inter cooler for those boost levels.

M5

Thanks for the advice. I was planning on doing an Inter cooler but I wanted to wait till there was snow on the ground so I can do a before and after test with charge temps.

I was also thinking of adding it more to the rear of the sled under the tunnel and getting all that fresh snow up on it. To me on the nytro the inter coolers I have seen that are up front dont get alot of air movement thru them and could actually act more like a head sink.

Was thinking something like this.


Keep in mind I still trail ride this thing in MN so I want to keep the head light and sled stock appearing as possible (sleeper:face-icon-small-ton)

Has anyone tried just a timing key to retard timing? I use to use these on my Turbo 2 Stroke sleds and they never hurt the bottom end and really helped against detonation.
 
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TurboM700

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Nov 26, 2007
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So would a standalone controller like Motec, with boost control and anti-lag but unfortunately the government wants to much of my money so I dont get to spend it on fun stuff. :)

Anyone have any input on placing the intercooler behind the turbo under the tunnel about the only cons I can see is rocks/ice getting throwing up at it.

Mike
 
M
Jan 14, 2004
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IMO that's not what you want to do. First problem I see is as you stated rocks and ice. Second problem is an intercooler is designed for air to air not snow to air so you will need a different core, as mentioned above liquid/air is where you want to be and lastly I think the charge tube plumbing is just too long. Everybody's kits place the intercooler in the nose and they work fine. If you are worried about it you can add a few vents and a fan.

JMO

M5
 

Matt@MPI

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Dec 3, 2010
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I did the timing reflash thru MPI last year and did not have good results. I was trying to get away from race gas on a supercharger setup and it seems to have just killed the sled. No top end at all. MPI is a good company that has been good to work with but I'm going to try a stock ECM this year and compare them the same day on the snow. I'd rather run a little race gas and have the performance than the what I have right now. Maybe I just got a bad one. So far I'm not impressed with the reflash at all.

How much boost were you running before the re-flash and how much after? If you were running 12 for example on race gas and you re-flashed and still run 12 I could see a loss of power felt when riding. But if you were running 8 on pump and you re flashed and then run 10 you would more than make up for the loss of power on the top end. The re-flash you might give up around 2-3hp but you would gain back 10-20hp with more boost. The head shim would react the same way. But it would also kill the bottom end. There is always a compromise to everything.
 
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TurboM700

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Nov 26, 2007
393
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St. Anthony MN
Matt,

What will the timing reflash get me?

6pounds at sea level to what? (assuming fuel and intercooler are taking care of)

How much timing is removed at the top end?

Just wondering what my 250 dollars is getting me?
 

Matt@MPI

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Dec 3, 2010
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Matt,

What will the timing reflash get me?

6pounds at sea level to what? (assuming fuel and intercooler are taking care of)

How much timing is removed at the top end?

Just wondering what my 250 dollars is getting me?

6# at sea level is safe. With the re-flash 8-9#

Safety Flash: In this software recalibration, the engine timing is re-calibrated to reduce ignition timing as water temperature increases and the temperature light illuminates 20 deg F sooner than stock (stock 212F, now 190F). The stock parameters are not sensitive enough to protect the engine while under boost. When the stock program turns on the temp light while on boost, the engine may already have been damaged. Our software flash protects the engine by reducing timing as water temperature increases to help safeguard against engine damage. The rider is also alerted by illuminating the water temperature warning light.
Part # HSE-0060 $299

Reduced Timing Flash: In this software recalibration, the ignition timing tables are re-mapped to compensate for boosted applications. Ignition timing is gradually reduced as the engines load (throttle position) increases which is essential in eliminating engine detonation. The reduction of ignition timing allows for more boost at any given octane fuel. Example: if OEM programming is safe at 5PSI of boost, this re-map would allow 8PSI of boost while using the same fuel. A second example: Vehicles running race gas to allow a given boost level could now be run with pump premium fuel. It many cases this flash can eliminate the need to run a head shim (and remove all the liabilities of having to disassemble and reassemble the engines cylinder head). A good rule of thumb is that this calibration allows for 2 to 3 more PSI of boost without further engine modification or fuel octane increase.
Part # HSE-0062 $299

Safety Flash with reduced timing: In this software recalibration, the safety flash and reduced timing flash are combined to offer the ultimate performance and engine safety package.
Part # HSE-0061 $399 (a $200 savings)
 

smwizzz

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May 6, 2008
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Ft McMurray, AB
Awesome

It is always good to see people giving good service. MPI seems to have a great repoire. If you are running their kit and they offer advise, listen.

Some of us have been the test dummies for the manufacturers of kits. It has left bad tastes in our mouths and skepticism when we look at new stuff. I have been following the forums and these guys seem to be a great bunch by their interaction with customers.

My experience has taught me that the gems style controller is not my preference. There are a million things we can buy for our sleds but the bottom line is if it doesn't run well we may as well sit at home because it takes the fun out of riding. I personally run Neil's Boost It system. I had a couple tuning issues right off the get go but we have now managed to make it work flawlessly. Last season I had no issues at all. I have not spent the time to really fine tune it because it was a treat to actually ride my sled last season without working on it for the first time since I bought it in 08 with a Gems controller...

If I was to do a kit again I would have to seriously consider a couple kits. Neil's would be one and MPI would definately be one. There are a couple others out there I have looked at that have caught my attention but they need some proving as of yet. Something to think about if you are looking at spending the $$$ on an intercooler is the liquid to air system. I am not familiar with MPI so I don't know if they offer one. I do know a couple kit manufactures are doing this now. Neil is one of them... and with great success.

I am not trying to sell a NM kit. I am only trying to direct you to pay attention to the kit builders with experience and who offer service. No service sucks! I know from experience. I have a couple other buds who spent $$$ on the latest greatest kit and are in the same boat as me. I can assure you, there are a few kits WE WILL NOT BUY!!!

Cheers!!! Happy trails!!! :face-icon-small-hap:face-icon-small-hap:face-icon-small-hap
 
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TurboM700

Well-known member
Nov 26, 2007
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Well I guess I should update this.

I have a choosing to go with the PCV V PTi and use there timing module to pull timing based on boost. It will be a little more of a learning curve then just buying a pre-programed ecu from MPI but this way I will have ultimate control over the ingintion and fuel timing.

I'm also switching out the turbo to a KPA with a S.S housing and external waste gate along with adding a inter cooler.

This should be a fun yr.
 
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Turbo11T

Well-known member
Nov 26, 2007
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Lake Crystal, MN
Well I guess I should update this.

I have a choosing to go with the PCV V PTi and use there timing module to pull timing based on boost. It will be a little more of a learning curve then just buying a pre-programed ecu from MPI but this way I will have ultimate control over the ingintion and fuel timing.

I'm also switching out the turbo to a KPA with a S.S housing and external waste gate along with adding a inter cooler.

This should be a fun yr.


Sounds like a total redo! Either way should be fun. Sounds like you are the kind of guy who enjoys the fabrication part of the sled as much as the riding! Would love to see the sled when you have it all done!
 
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