Okay, summers approaching, and my only goal for summer '06 is to either A. Rebuild my motor (S4 turbo with 145,XXX), B. Order a Crate motor from Mazda, or C. Order a JDM motor. Which would be the best?

Crate motors go for about $3000 according to a tech at AIM tuning. Biggest advantage i see here is that you're starting with a 0 mile motor.

Rebuilding is what i was considering, but for the seals kit and how housings (mine are probably unusuable, refer to mileage above), it would almost be the same price to go with the Crate motor.

JDM motors is what im most strongly considering. You can get them with about 12k on them for about the same price as a crate motor. 12k is perfectly broken in, and unlike the crate motor, this comes with the turbo and everything. I'd be upgrading to S5 motor if i did this.

Any advice you have or experience with any of the above you'd like to share, please do.

 

Crate motor? Can you actually buy a brand new motor? I thought it was only a reman...

and JDM motors are a big gamble. You don't really know the history behind most of them.

 

Rebuild it.

 

If you buy a JDM motor isnt there a chance that you may have to rebuild it or do they sell in factory spec?

I'd go with a brand spanking new motor, but I've never heard or seen any. Would like to know more about these crate motors.

 

i was considering this also (getting a s5 motor when mine goes)

the thing with a s5 motor is that you also get the turbo, which might be going in yours already. but again i think this is a touchy subject unless you use all new parts (rebuilds dont always use ALL new parts) a jspec can be just as good as a rebuild. but like mentioned before it really is a toss up if you get a good jspec motor

 

12k now I have never seen a JDM motor with 12k on it these days. I would buy the JDM motor and have it rebuilt right off the bat.

 

Or at the very least get new gaskets and coolant seals put in it... for all you know it might run but have a massive internal coolant leak, or an oil leak on the inside or outside.

And check the tolerances on the seals while it's open as well.

Even for Japan, 12K miles would be incredibly low for a 16 year-old engine, unless it was from a seriously wrecked car that hasn't been driven for a long time (which means the core is probably shot).

Of course most people forget that in Japan, the number of hours driving per mile is much higher than those in America... which is why to the Japanese, 100,000 miles is very high for a car that's still running, whereas that's the norm for any car over 6-7 years old that still runs in the US...

 

go JDM with a first rebuild in it, Mazda remans are high in price and I know of two rex's that ran on remans that both at ~5k, had the water pump seize up, one is a family member's 88 N/A in SC, the other is now now 87 TII.

 

I like the idea of doing a JDM motor and rebuilding it...but I think its too much. Not like that....i mean that someone like me, with little experience in rotary engines, it would be a feat if i got the JDM motor in, wired, and running, not to mention rebuilding the damn thing. I just set up an intern type deal at a local rotary shop, so I'll have access to professional knowledge...do you think this is the way to go? Oh and i didt mean 12k, i meant 30k...sorry. I guess with that many miles on a j-spec car a rebuild wouldnt be such a bad idea. besides, that car had to wind up in a junkyard somehow. it doesnt take much imagination to see a jdm FC smash into a guardrail at 100kph. it was probably driven hard

EDIT: Also with the JDM you can sell your old engine or part it out. Actually that'll probably pay for most of the new motor. ****** a. and since the TII is my daily driver, i can port the JDM before install it. oh and idk if theres a writeup somewhere on the internet about how the hell to wire a JDM motor?

 

You COULD just put the engine in there... but you can't really garuntee how long it will last unless you take it apart and check everything.

I did my own rebuild (just the soft seals) by myself, and it wasn't all that hard, just frustrating, because I had to do a lot of stuff over and over again... and I've never put a car engine together before.

Then again I don't know if it'll actually run right or not yet

As for the wiring, at least for the S5 all you've gotta do is use a left-hand drive spec harness and any S5 turbo ECU... I'm not so sure about the S4...

but you should definately start researcing this stuff.

(and you can only sell what parts of your engine are still any good...)

And pulling/installing the engine is not hard at all... well, pulling isn't... lol

 

so we are in agreement that you can't buy a BRAND NEW crate motor from the factory? Reman != new motor

 

a reman is not a new motor, simply a motor built up from used parts that are still within spec.

 

right, sorry, the crate motor i was referring to was a reman.