Lets talk compression and boost
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From: Ft. Lauderdale
the biggest benefit of the lower compression is lowering the peak cylinder pressure, the amount of pressure in the cylinder when the spark happens. lower peak pressure (pressure ratio) the less stress on the whole motor, the happier everything will be 
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From: Ft. Lauderdale
Originally Posted by HvRRZ,Feb 8 2009, 09:33 PM
I'm sure having the AEM Methanold set up helps a lot. How is your experience with it thus far? How often must you refill the tank? I know that does depend somewhat on how the car is driven.
My only fear with that system is if there is a malfunction and it stops working...then hope the engine doesn't go boom. Is there a fail safe in the system? say switching to a second tune if it fails.
My only fear with that system is if there is a malfunction and it stops working...then hope the engine doesn't go boom. Is there a fail safe in the system? say switching to a second tune if it fails.
http://www.aempower.com/ViewCategory...CategoryID=120
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From: Los Angeles, CA
Originally Posted by candymanjl,Feb 8 2009, 08:41 PM
the AEM meth kit when set up right has a few failsafes...
http://www.aempower.com/ViewCategory...CategoryID=120
http://www.aempower.com/ViewCategory...CategoryID=120
thanks.what an amazing system, and to think it costs so little. I wonder why so many would rather go with the aquamist unit...
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From: South of the pier, Huntington Beach, CA
Originally Posted by HvRRZ,Feb 8 2009, 07:29 PM
Sideways I cannot maximize the image...it seems my membership has run out :/
From the looks of it the difference is very minimal throughout the power band as far as hp. Looks like the biggest difference is seen in bottom end torque, which is to be expected. Were these dynos done on the same pulley?
From your experience would you recommend I go with a slightly lower compression ratio if I plan to boost 10psi, and not any higher? I think the 2.4L will more then make up for the slight drop in torque if I do, but then again if it's not really necessary then why bother.
From the looks of it the difference is very minimal throughout the power band as far as hp. Looks like the biggest difference is seen in bottom end torque, which is to be expected. Were these dynos done on the same pulley?
From your experience would you recommend I go with a slightly lower compression ratio if I plan to boost 10psi, and not any higher? I think the 2.4L will more then make up for the slight drop in torque if I do, but then again if it's not really necessary then why bother.
RPM : difference in ft lbs
3000 : 9
4000 : 9
5000 :14
6000 :15
7000 :17
8000 : 8
8300 : 3.8
9000 : 6
It appears the difference at the peak torque 8300 rpm is smaller than at both 8000 and 9000 rpm.
I did not look back and upped the boost soon after that dyno.
If you are running a stock block then do the boost you want. If you are building a 2.4 FI motor then lower the compression.
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Sideways thank you. The information you've shown is exactly what I wanted to see. Some hard evidence of exactly what effects there will be when the compression ratio is lowered, and the boost is kept the same. It doesn't hurt that you are also supercharged which is why I'm asking all this. I'm still surprised that the effects were so minimal, but also glad to hear of it.
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From: Los Angeles, CA
Originally Posted by stena,Feb 9 2009, 02:52 AM
is there a tread or info to AEM water injection? i am thinking of getting one so people who already went trough the pain of install and modify would help a lot.
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From: Gie
Joined: Jan 2008
Posts: 9,570
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From: New Jersey
The Tuner can set up some failsafes, but there is a little green LED light that comes on when you start to spray (brightens depending on the flow), and it is constantly testing itself, I had a loose wire and it was blinking so I new not to BOOST etc........ It also blinks when it is low on fluid. I fill it up once per Fill up at teh gas station, but even then there is more left, I just top it off to be safe. The only annoying think is BLUE DYE around the BOV area
I did a little experiment this fall......
I was stuck in traffic so I decided I would take the back roads and open her up. Before I did this I popped my hood and burned my hand on the charge pipe and intake manifold, I wanted to feel how hot it was, it was BURNING hot, so I get back in the car and go WOT winding out the gears to about 100MPH then pull over and pop the hood again.............The charge Pipe and Intake manifold, as well as the Intake side of the Valve cover were COLD!!!!!!!!!, I don't mean like room temp, it was COLD
Here is my INSTALL WRITE-UP
https://www.s2ki.com/forums/index.php?showt...&#entry14425116
I did a little experiment this fall......
I was stuck in traffic so I decided I would take the back roads and open her up. Before I did this I popped my hood and burned my hand on the charge pipe and intake manifold, I wanted to feel how hot it was, it was BURNING hot, so I get back in the car and go WOT winding out the gears to about 100MPH then pull over and pop the hood again.............The charge Pipe and Intake manifold, as well as the Intake side of the Valve cover were COLD!!!!!!!!!, I don't mean like room temp, it was COLD
Here is my INSTALL WRITE-UP
https://www.s2ki.com/forums/index.php?showt...&#entry14425116