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er27 possibilities??


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ok, i've been lookin to get an xt6 for offroading purposes..... now, i was wondering if you could do a piston swap from an ea82 to get higher compression......... i have heard that the two motors are basically the smae, just one has two more cylinders.............i was just thinking on it, thought it would be an easy way to get a whole heck of a lot more power, and for cheap too.........

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The ER is already at the top of the compression line as far as the EA motors are concerned. If you go any higher your talking 10:1 plus, and it does turn into an interference good for power, bad if a T-belt goes. If you really want to raise the compression, without a whole lotta work, then 5psi will do that for ya, and an IHI RHB5 will more than put out enough, least with the stock compression ratio.. . . . these are things I've thought of many times already.

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ok, i've been lookin to get an xt6 for offroading purposes..... now, i was wondering if you could do a piston swap from an ea82 to get higher compression......... i have heard that the two motors are basically the smae, just one has two more cylinders.............i was just thinking on it, thought it would be an easy way to get a whole heck of a lot more power, and for cheap too.........

Contact Paul Singer in the Yahoo XT6 forum. His XT6 is supercharged. I figured a supercharged XT6 would be great for off-roading purposes.

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ok, i remember reading in the fix all book, that the xt6 has the 7.7:1 pistons, not the 9.5:1 pistons, that is the whole reason why i was looking into doing this, because it would be easy, and the parts are easy to find....... i could be wrong, but if i were to use the 9.5:1 pistons, it would not be an interference motor, because it has the same insides that an ea82 has....... right? im kinda lookin at keepin it naturaly aspirated, i dont want to go into turbo or superchargers yet because that requires a lot more work than what i have time and money for......

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That was most likely an XT turbo with 7.7:1, as the turbo motors are the only ones with that low of compression, even the old EA81's had a little over 8:1. I'm almost definate that all the MPFI(non-turbo) engines had at least 9:1 compression, but I think that the SPFI and er27 had 9.5:1.

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I am running a piston with a slight dome and a smooth surface. With the cam belt off and rotating the engine by hand I can get the valve stem to bump back against the cam follower by just the smallest ammount on the first rotation (valve set to full open) and nothing after that. I think I would be OK if I lost a timing belt but I am not interested in testing it. In the end, I am not facing any more risk than any other interferance engine such as my EJ25.

 

You dance, you pay the piper.

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ok, i remember reading in the fix all book, that the xt6 has the 7.7:1 pistons, not the 9.5:1 pistons, that is the whole reason why i was looking into doing this,
That's incorrect! A typo perhaps. I do remember reading the same thing myself either online or in a Chiltons (or like) service manual. The FSM (Factory Service Manual) states the compression ratio for the XT6 is 9.5:1.

 

On the good side, I've read online that it's a closed deck engine, which really surprises me.

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