Head Gasket replace? Or motor swap

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Scoobybob
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Head Gasket replace? Or motor swap

Post by Scoobybob »

Hi all,
On my way back to NC from Florida I blew my head gasket. I had a couple of thoughts. The car has 200K miles, I was thinking of getting one of these japan import motor (with supposably 40 - 50K miles) for $895, Replacing the head gasket, or seeing what is involved in a WRX turbo 6 speed. Do not know what is involved to do that transformation.
Anyone with experience with this?
Thanks
Bob
ZUBAJA
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Re: Head Gasket replace? Or motor swap

Post by ZUBAJA »

My experience (having done HGs on 2 Foresters). You'll only want OEM head gaskets or the company from (I think it's in Oregon somewhere*). Each HG is about 100.00. You will need the rest of the gaskets. There's also the "oil seperator" behind the flywheel. The engine will have to come out (some on the internet have done it with the engine in, but I can't imagine doing it that way - not "right" anyway). some say new head bolts, some say the old ones can be reused (I reused mine with no problem). With 200K, I'd consider new rings, maybe pistons (the first one I did I @ 195K, had all the rings within the factory specs, so I cleaned all the ring grooves and reused the rings too). Again, at this mileage, I'd have the heads done. Add all of this up, and you're close to the JDM engine price.
From what I hear on the JDM engines, they need to be drilled and tapped to install the EGR pipe. Don't think that's too difficult. Because the JDM engine has been sitting, I'd replace the water pump and timing belt / components. It's about 6 - half a dozen.
On the "6-speed turbo", from the prices I've seen (6 speed ony) it's between 3 and 4 k for the components, and I don't think you really gain anything other than an extra gear (top end RPMs were the same IIRC). Not sure what all is involved with a turbo swap, but that too, might be involved. Dennis
EDIT: I used the Subaru OEM head gaskets for the 2006 SOHC engine, and I used the "Six Star" from All Wheel Drive in Seattle for the 1998 DOHC. The 2006 ran fine with no problems until a drunk turned left in front of it totalling the car, and the 1998 is still going strong.
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kamesama980
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Re: Head Gasket replace? Or motor swap

Post by kamesama980 »

Bob, do you currently have a turbo or non-turbo (NA or naturally aspirated) car?

if NA: Yes, six star is the company that makes the good replacements. I've also heard of using turbo gaskets (because they're MLS rather than composite) but can't verify. I would absolutely recommend repairing the existing engine with a genuine subaru master engine gasket kit plus the six-star head gaskets. This is my plan for my 03 once I get my 05 turbo back together.

if turbo: OEM are fine.

yes, STI 6-speed swap will run you 3-6k depending on how good you are at finding parts. That's without an engine. Not really worth it unless you're making enough power to break the turbo 5-speed.

JDM swap... I don't like these because as good of condition as they say they may be, it's swapping the devil you know for one you don't. Also note most of them are also 2.0s not 2.5s. While some claim "they pull better to redline", and I won't dispute that they don't run out of breath up top, the fact is the total power and torque is less overall. Not a good candidate for the portly Bajas (lightest trim is over 3600lb empty!) especially if you actually do work with it.

Swap a turbo engine in... again there are a ton of variables in the cost/difficulty. might manage $1000 with deals and cutting corners, might be in it another $5-10k before you're done. I thought about it then just got a factory turbo Baja. It's not just the engine but the trans, diff, axles, electronics, exhaust, cross member, etc.
-Russell
"You don't get to judge me for how I fix what you break"
03 sport 5mt
05 turbo 5mt vf39 and other STI bits, 3" turbo-back
Scoobybob
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Re: Head Gasket replace? Or motor swap

Post by Scoobybob »

I defiantly need a manual.. Does the Turbo make that big of a difference? My baja is a 2.5, I guess I can not just add a turbo to my motor..

Bob
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kamesama980
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Re: Head Gasket replace? Or motor swap

Post by kamesama980 »

The turbo can make a huge difference... or it can blow up the engine. or you can piss away a lot of time/money doing it wrong and it makes little difference. If you want to add a turbo, just spend the next year reading about doing it, then bother.

If you want to start modding, great. First, buy a reliable second car. next, what's your budget? 6 speed will start about 3k for parts. turboing your engine could be done for under 500 but that's a lot of hackery and knowledge and parts that were just laying around and goes as far as you want to take it. Third, what are your expectations: price, power, reliability: pick 2. price, easy, reliable: pick 2. you get the idea. I started going down the rabbit hole and decided to just get a factory turbo Baja as there's no way I could match it for price and reliability (much less ease) hacking stuff together.
-Russell
"You don't get to judge me for how I fix what you break"
03 sport 5mt
05 turbo 5mt vf39 and other STI bits, 3" turbo-back
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