JDM imported engines, Are they reliable? Options

[CarlJ]

Hi,

I'm new here. Please forgive me if I this has been posted in the past. I tried the search function.

Anyway, I read this on a civic forum(http://www.7thgencivic.com/forums/showthread.php?t=179335):

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JDM Swaps

Honestly, unless these come from a friend in Japan, you're taking a gamble every time. You have no real way to know how many miles are on the engine, nor how it was treated. Just keep that in mind. It has not been proven (no matter how many claims) that these JDM motors make any more HP.
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Now I'm wondering, is any of this true? If you're able to find a trustworthy company that sells these engines, shouldn't everything be ok?

I've noticed a lot of you have done the 3S-GTE swap - did any of you import the engine from Japan, or got it from a company which imports them? Experiences with this?

[Kwanza26]

Same idea applies to all engines, not just used JDM motors. Exact mileage and such will always be a mystery unless the engine came out of a clip with the ODO available. Typically speaking though, most JDM engines are of relatively low miles and are in relatively good condition. It's your job as the consumer to check it out. Compression and leakdown, replacing gaskets/belts, etc. Be sure to get a warrantee also...

As for the power... the engines are usually the same unless there is mechanical different. Take Honda engines for example, the JDM counterparts are sometimes much better because of more agressive cams, better port shapeing, different intake/exhaust manifolds, ECU tuning, etc. Japan has better fuel available so their ECU tunes can be more agressive. Toyota 3SGTEs are no exception. The JDM counter parts (ST185 3SGTE) have higher static compression and slightly different set-ups which account for 20 or so more HP. It's mostly related to the available fuel and emissions.