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View Full Version : How many miles are too many and what is the cost to rebuild an engine?



Kalstar
06-19-2012, 06:34 PM
I have found several WRX donors locally in the $2500.00 range with 140K-160K miles. Is it worth it to buy a lower mile donor or buy the cheapy and rebuild the parts?

Thoughts......

BipDBo
06-19-2012, 06:48 PM
It seems really hard tofind a subie with less than 100,000 miles. A wrecked WRX with low miles would be ideal, but when the 818 hits the market, those may all get snatched up.

How many is too many? I'd say it matters more how it was driven. You're not going to find a WRX that was used by grandma to go to church and bridge club, but you might find a reasonably conservative driver, maybe some guy who had a mid life crisis but eventually traded in for a Buick. Check the exhaust for the oily smell, and see if it shifts smooth. It would probably be prudent to do a compression test. If you're doing a budget build an older engine might be fine. If it's in decent butr not perfect running condition, you can always get the car done and on the road and rebuild sometime later.

Etos
06-19-2012, 08:09 PM
I'd go for a higher milage engine. If you're going to rebuild anyway then might as well get it cheaper. Rebuilding doesn't cost much. Bearings, piston rings, valve caps, timing belt+water pump, gaskets would be around $3-400. The only issue would be if the cylinder walls, pistons and valves are still in good shape. With a higher milage I'd probably change the pistons too just to be on the safe side.

Mechie3
06-19-2012, 09:01 PM
Gasket kits are ~ $250, OEM pistons are as expensive as aftermarket. I think a build can be done for $1500 or so. I've built some, find it easier to simply buy a new OEM shortblock and put heads on them. My dealer gives me 20% off all parts so I can get 2.5L STI blocks for $1800. $250 in gaskets and I have an almost new engine for $2k. Only things that get reused are heads and all components. I sell off the used stuff. 2.5L blocks pull a premium over 2.0L blocks (~$200-$300 for bare block halves on NASIOC).

PhyrraM
06-19-2012, 09:07 PM
I just had a 2.5liter DOHC motor from a '98 Legacy Outback rebuilt. It was a stock rebuild, but done by a shop that normally builds race motors. It was built with the same detail as he puts into race motors, but using stock parts and tolerances. $1300 for the shortblock. That includes new pistons and rings, bearings and all the o-rings and seals. The labor included balancing, line bore the mains (if it was required, didn't ask), torque plate bore and hone, surface the decks, and shortblock assembly.

The heads were about $700. They were pressure checked, cleaned and decked. At least 2 valves replaced, all new guides and seals, valve job, valve adjustment including cost of required shims.

Add about $100 each for a factory water pump and oil pump, about $200 for an OEM gasket set (includes the head gaskets) and about $130 for a Gates timing belt set (that includes all the idlers).

I may have overpaid a bit on the labor, but I have nothing in the back of my head bugging me about the build and I know Greg will stand behind it if need be. Peace of mind is still worth something to me.

So, mine was:
$1300
$700
$100
$100
$200
$130

$2530 for a stock, but done right, build. Rebuilding a turbo motor to stock specs shouldn't really be any more expensive.

wallace18
06-20-2012, 04:59 AM
For a complete 2.0 WRX motor rebuilt with cam belts, oilpump, waterpump and covers I have seen for 3100.00 to 4800.00. I think the AJW donor kit may in the long run be a better way to go, if you have the money for it. A high miles car will need lots of other stuff as well.

skullandbones
06-20-2012, 10:02 AM
I just had a 2.5liter DOHC motor from a '98 Legacy Outback rebuilt. It was a stock rebuild, but done by a shop that normally builds race motors. It was built with the same detail as he puts into race motors, but using stock parts and tolerances. $1300 for the shortblock. That includes new pistons and rings, bearings and all the o-rings and seals. The labor included balancing, line bore the mains (if it was required, didn't ask), torque plate bore and hone, surface the decks, and shortblock assembly.

The heads were about $700. They were pressure checked, cleaned and decked. At least 2 valves replaced, all new guides and seals, valve job, valve adjustment including cost of required shims.

Add about $100 each for a factory water pump and oil pump, about $200 for an OEM gasket set (includes the head gaskets) and about $130 for a Gates timing belt set (that includes all the idlers).

I may have overpaid a bit on the labor, but I have nothing in the back of my head bugging me about the build and I know Greg will stand behind it if need be. Peace of mind is still worth something to me.

So, mine was:
$1300
$700
$100
$100
$200
$130

$2530 for a stock, but done right, build. Rebuilding a turbo motor to stock specs shouldn't really be any more expensive.

This is an enlightening discussion for me and probably many others who have not delved into the Subie technology. It sounds like the rebuild process and cost is very similar to doing it on a small block Ford. I got a "crate engine" no frills and took the E7 heads off and replaced with my modified heads using the springs and exhaust valves from the new heads (matched to cam), added a waterpump and had a balanced and blue printed engine (dyno tested) for around $2600. So that is a releif to know that the engine work isn't going to cost all that much. I agree that if you shop prudently, you should be able to find a well used running engine and have it worked over. The replacement of the pistons is probably a good tip. I don't know if you can have them magnifluxed first (cost) or if it would just be better to replace with OEM as a matter of peace of mind. Again: very good thread. Thanks, WEK.

Mechie3
06-20-2012, 10:11 AM
subarugenuineparts.com is a good place to find OEM parts at a decent cost. Shipping is the only downside. A lot of the better Subaru dealers have relationships with local Subaru clubs and offer discounts as well in order to bring in business.

PhyrraM
06-20-2012, 11:11 AM
The actual machine procedures are pretty much the same as most motor. The difference is that a good Subaru rebuild *requires* some of the steps that only 'built' or race motors of other makes get.

For example, checking the line bore, line boring the mains, boring and honing all require torque plates (plural). This is because of the very compact dimensions, the aluminum castings, and the fact that the head bolts penetrate deep into the block near the crank and base of the cylinder walls - all causing a bit more distortion than most builders are used to. Most builders do not have Subaru torque plates. Those that do *may* charge more than normal to pay for the extra inverstment.

Also, there are special assembly/disassembly requirements that can simply baffle the unaware. The piston pins are pulled through holes in each end of the block, leaving the rods on the crank. There are a few hidden bolts holding the cases together. There are specialized o-rings between water and oil passages at the block joints. In my experience, shops that don't do Subarus will charge you for thier 'learning' hours, possibly damaging your stuff while they learn.

Cliffs notes: Subarus are nothing more specialized than an old air-cooled VW, but require better attantion to detail.

Arrowhead
06-20-2012, 01:42 PM
WHOA! Found this on the bulletin board this morning!! Cheap enough just to buy to run around the back 40 until the 818 comes out!

https://lh4.googleusercontent.com/-hHQsUCGoJaM/T-IYG98O33I/AAAAAAAALEk/g3h7RQr0oec/s512/2012-06-20_08-31-06_351.jpg

Kalstar
06-20-2012, 02:31 PM
WHOA! Found this on the bulletin board this morning!! Cheap enough just to buy to run around the back 40 until the 818 comes out!

https://lh4.googleusercontent.com/-hHQsUCGoJaM/T-IYG98O33I/AAAAAAAALEk/g3h7RQr0oec/s512/2012-06-20_08-31-06_351.jpg

I thought 2002 was the first year of the accepable donor for the 818.

Xusia
06-20-2012, 03:03 PM
Earlier years won't be a single donor (meaning, it won't have all the parts), but they will have most of them and what they don't have is easily obtained. Considering the $600 price, it's a STEAL...

Kalstar
06-20-2012, 08:30 PM
So what would be missing that would need to be exchanged with the newer model?

I'm thinking with the higher mile donor and the fact it only costs 2500.00 or so to rebuild, can't be too much more to hop performance since the engine is open anyway.

PhyrraM
06-20-2012, 09:30 PM
That donor will have everything you will need, but some modifications may be needed.

Off the top of my head:

The motor in the '98 Impreza is a 2.2 liter SOHC non-turbo. About 130HP. Reliable as all getout. An honest 250K motor if taken care of.

The 5 speed transmission *may* need a slightly different 2WD conversion kit.

The front control arms will be the narrower "WRX wagon" width and the front control arm bushing will need a few shims to match the bushing width of the proper donor.

The pedal assembly has a few holes located differently by a few MM. Same for the steering column. Shouldn't be an issue a drill can't easily solve.

The steering rack to column interface has slightly different splines, so *if* FFR provides extensions or such that may need to be addressed.

Seats are more pedestrian, but sit slightly lower.

Front brakes are much smaller than WRX, but with the light weight of the 818 I see how that could be an advantage.

Rear brakes *might* be drums, depending on trim.

Instrument cluster will have a slightly different shape.

Uses a throttle cable like the '02-'05 2.0 liter WRXs.

*Might* use a cable clutch. Would need to source a hydraulic pedal assembly and transmission if so. The transmission *might* be able to be converted (I never researched).

Im sure there are more, but that gives a good idea of the scope. Overall nothing to difficult to someone assembling thier own car.

Kalstar
06-20-2012, 10:47 PM
I'll stick with an 02 plus.

Arrowhead
06-21-2012, 07:25 AM
Ha Ha, I just thought it was ironic to find a subie for sale so cheap, most cars that cheap attract scrappers. Thanks for the clarification PhyrraM. I think I'll wait till to get a correct donor. I don't think it they will be too hard to find cheap wrecked, these kid thrash these WRX's on a pretty consistant basis (I know, my son has one)

flynntuna
06-21-2012, 01:26 PM
I've been looking on Craigslist here in San Diego, these guys are asking 10k+ for '02-'04's. Thought I'd buy one for a daily driver to get to know more about them before it becomes my donor. Not only do they thrash them they think they can get a premium price for the privilage.

Mechie3
06-21-2012, 02:15 PM
I've been looking on Craigslist here in San Diego, these guys are asking 10k+ for '02-'04's.


Insurance gave me $16,275 before TTL for my totaled 06 with 75k miles on it. NADA listed it as $16,475 and KBB listed it as $17,500.

Most 02/03 (bugeyes) tend to sell for $5k for a beater up to $8k for a nicer one with lower miles. 04/05 (blob eyes) sell for $8k to $12k it seems. 06/07 (hawkeye) go for $12-$17k.

Dealing with people on forums though, I've found most people think their beat up piece of poo is worth $premium and any part you're selling is worth $20 AND you should ship it to them on your dime.

Mechie3
06-21-2012, 02:48 PM
One more thing. Two of the biggest killers of Subaru motors: no engine management, low oil.

Subaru says normal oil consumption in turbo models is up to 1 quart every 3000 mi. Lots of people spin bearings due to low oil.

It's easy to put on a catless downpipe and turn up the boost, and easy to blow the motor. There's an open loop/closed loop delay in the ECU that causes the motor to run stoich when first hitting boost. When the ECU is tuned, this delay is changed to zero so that the car runs rich under boost and doesn't knock. When looking at cars from owners, ask if they ran engine management with their mods or not.

PhyrraM
06-21-2012, 03:07 PM
IIRC, that particular delay problem doesn't effect '02/'03 WRXs. There was a changing in engine operation/programming starting with the '04s.

One of the reasons '04s got a bad rap is because folks starting treating them like they had '02-'03 (and prior JDM models). Who knew at that time, right?

However, having the cars tuning history available is always a plus.

flynntuna
06-21-2012, 03:22 PM
Good tips, I think I'll also reread the subaru tips in the early threads, thanks

Mechie3
06-21-2012, 03:50 PM
Don't know when it started. I know STI's don't have the delay (or a much shorter delay). I didn't come onto the "scene" until 06, and by then there was enough information (and dis-information) that people repeated without knowing all the details. The engine management thing was one of them.

Unabomber's Manifesto is a great resource organized by topic for all things WRX related.

http://forums.nasioc.com/forums/showthread.php?t=533787

EDIT: At some point the ECU also changed from a 16 to 32 bit. If you plan to mod the car, the 32 bit has fewer limitations.

PhyrraM
06-21-2012, 06:11 PM
EDIT: At some point the ECU also changed from a 16 to 32 bit. If you plan to mod the car, the 32 bit has fewer limitations.

That one is easy..For the North American markets.....2.0 liter are 16 bit (and cable throttle), 2.5 liter are 32 bit (and fly-by-wire). This is for the turbo motors - I don't know what the non-turbos have.

Kalstar
06-23-2012, 05:51 AM
So we know about the build costs now, but what about the miles? How long are these engines good for?

Mechie3
06-23-2012, 07:18 AM
Depends. My 93 legacy had 140k miles when I gave it away to a family friend. Last I heard they were still driving it several years later. My wrx ran into some bad luck and I replaced the motor at 35k miles. If it was properly maintained they last well over 150k.

PhyrraM
06-23-2012, 09:04 AM
The 2.2 SOHC will last virtually forever with proper maintenance. 200K+ examples can be found all day long.

But, I assume most are curious about the turbo motors.
From personal experience:

2002 WRX. Always stock. Always driven fairly hard, redlined at least once per trip. (It's fun.) Oil changes at 5-7K intervals. Once or wice streched to 10K. Mobil 1. (recently come to light that M1 may not be the best choice) 140K miles so far, only replaced a radiator. Runs as strong as the day I bought it, power steering pump or alternator bearing is squealing a bit until warmed up. Clutch, timing belt+idlers, water pump, plugs and coolant all done @110K.

1993 Legacy turbo. Stock. 279K on what I strongly believe to be the original motor as there were none of the normal tell-tales of the motor being replaced. The last 60K of them were mine and well maintained. I pulled the motor because of a bad headgasked cause by my playing with the engine management. Crosshatching still visible.

Thoughts on mileage on built motors. There is a very long thread on Nasioc on this. I never read it because there are too many variables and too many poorly built Subaru motors out there. There are too many bad tunes, even from 'good' tuners. Factory tunes tend to be safe and rich - this helps keep motors alive, but also leave power on the table. There is very little reason for a well built and safely tuned motor not to last many, many miles. There does seem to be very few actually built this way. I, personally, think that the owners and tuners 'get greedy' and push thier tunes close to the limit - thinking that "it's still safe" or "I'll take care of it" and then when it pops, blame everything but thier power hungyness.

Another problem that doesn't often get discussed is the power level that a motor is built for, specifically clearances. If a motor is built by a guy who knows what he is doing with 350 HP in mind ALL of the clearances are designed for that power level (technically thermal load). If the owner decides at some point after that to swap his turbo and injectors and 'go for broke', all of a sudden all his clearances (especially piston-to-wall) are too tight and he wonders why things are worn out and at service limits @40K (or less) miles. If he builds for 450HP and only pushed 300 he wonders why his motor sounds and feels 'loose'. All of these things are generally more critical than in a corisponding V8. A 500HP V8 puts 62.5 HP through each piston and connecting rod bearing - and usually at a lower RPM then a Subaru. A STOCK STI is already putting 75HP through the same parts. 100HP each for 400HP and 125HP each for the same 500HP. They can do it, but the level of attention to detail is "twice" what it needs to be for more traditional motors.

flynntuna
06-23-2012, 01:23 PM
A friend of mine who owns a Porsche repair shop once told me when looking for a car, anything mechanical can be fixed, rust can't. The only difference here it seems the rust won't matter as much.