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2G pistons on 1G "big" rods and the need for timing control and/or h20/meth injection

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This is more a heads up than how to article, but non the less; Its a point need made for those of us considering this increasingly common upgrade.

The main problem faced when running this set up (2g pistons/ 1G rods/ 1G timing), is the combination of combustion chamber pressure and the aggressive timing implemented by the 1G ecu. The 2G ecu has less timing advance, and when you introduce the higher compression ratio of the 2G piston with aggressive timing of the 1G ecu, these two factors lead to massive amount of knock and possible loss in performance over "stock ". It can even lead to catastrophic engine failure if gone unnoticed for long periods of time.

I currently run this combo in my 1ga gsx with no regrets. I'll admit it wasn't always this way though. Unfortunately I learned the hard way, or you could say the hands on way.

Before my addition of DSMLink to engine controls, I was faced with extreme detonation after installing the 2G pistons. With out timing control, I had nothing to alleviate the detonation problem other than the addition of fuel. This hardly helped with knock and did nothing for performance. I was left second guessing my decision to use the 2G piston in the first place. At that point I'd have gone back to use 1G compression pistons if I had the choice.

With out getting to into the do and don't of tuning; I'll just say this; TIMING CONTROLE IS A MUST WITH THE 2G PISTON / 1G ROD MODIFICATION! I'll also recommend a good form of detonation control as well; ie Snow Performance 2D mapped water/meth injection (WI).

If DSMLink is out of the question, it may be possible to alleviate knock with chemical inner cooling ( WI). Water injection added to the 2G piston combo may control detonation enough to run conservative boost levels with out an ability to modify the 1g timing tables (?12 to 18psi?).

2G PISTON / 1g "BIG" ROD SUPORTING MOD REQUIREMENTS!
-550 fuel injectors (minimum)
-aftermarket fuel pump & regulator - stock pump rewire (minimum)
-Some form of timing and fuel control - fuel control (minimum)
-Some form of chemical detonation control (minimum with out timing control)
-DSMLink - Some form of logging ability (minimum)

I cant stress enough how important these supporting modifications are to this upgrade path, and if you can't implement every one listed as a minimum; you'd be better off saving your money for your next... next engine rebuild!

Hope this helps; Sean.
 
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