818 build questions

[Cnight]

Well I'm still waiting in the research and planning phase of building an 818c. I have a few questions.

1. Is it better to go with turbo or N/A engine? What are the pros and cons of both? I would like the turbo as I'm am a little bit of a power junky but don't need it if naturally aspirated works just fine.

2. I suppose it's normal to go with the manual transmission but does the automatic transmission work to?

3. As for a donor. Is it a bad idea to get a high mileage donor like around the 200k mark? If not what all needs to be done to make sure it runs good?

Thanks guys:)

[Hindsight]

1. It's really your choice. Turbo will obviously make a lot of power, and easily, but some (not many) feel it's too much power for the car. To decide, take a production car out there on the market that you want similar performance to, then find out it's power to weight ratio by diving it's curb weight by it's horsepower. Now take 2000lbs (average example of a completed 818) and divide it by that number and you'll end up with the HP rating you'd need to achieve similar performance. If you go N/A and stick to the Subie motor, you aren't going to get more than 175 or 200 at best.

2. Both have been done. See Aloha818's build thread for an example of an automatic. You'll have more things to do that aren't covered in the manual and may have to do some fabrication but it will work.

3. Some have gone that route, but at 200k, much of the stuff is going to be at the end of it's life and pretty well used up. All the wear items will have to be replaced, the engine will need to be rebuilt, transmission might need to be rebuilt, and the general conditions of the parts is going to be not-so-great. Your disassembly and cleanup will take longer and there is a higher chance you'll need to go out and by stuff to replace rusted, bent, damaged, or other worn out stuff. You really don't save any time and money doing this in my opinion. I would strongly suggest getting the lowest mileage donor you can find (hopefully under 100k) so you don't have to worry as much about rebuilding things, replacing things, and fixing things.

[john g]

My donor was a 2006 WRX (turbo) with 93,000 miles. I bought it from an insurance auction, and after transportation and selling off unused parts, my cost was $3,100. My car has far more power than I need. My car is a 5-speed.

Would I do a turbo again? I am planning to sell my 818 and start another project because I prefer building to driving. I am giving serious thought to an electric powered 818.

[Cnight]

I had my eyes on a 2007 wrx that had 96k on it. Guy wanted 11k for car then he broke a valve and had to replace the engine so he said price would go up��

[FFRSpec72]

I went the non-donor route, as I got all my stuff besides engine/transmission off craigslist for a little less than $800 and then a JDM EJ207v7 and 5 Speed shipped for $3200, So I'm in for about 4K in parts, and did not have to deal with the teardown and disposal of the donor

[AZPete]

I agree with what Hindsight wrote. If you haven't read through the Donor section of this forum, crack a beer and study it. I don't know where you live but understand that donors from rust states are worth far less than donors from non-rust states. Regarding your guy with the 2007 WRX, what he has in it does not dictate the selling price. . . . Oh no, this also applies to 818 builders, like me, who have added lots of coin. Keep planning because building a Factory Five car is one of life's great adventures.

[Mitch Wright]

I went with a 04 WRX Donor with 100K, I will say I was impressed with the how stout Subaru's are built. I had a year to prep my donor parts and sell off parts ($3200 in parts sales) which paid for 95% of my Donor. I went through and replaced all the wheel bearing and seals, new seals in the trans and if I was using stock brakes I would rebuild the calipers and replace the masters.
Now when I do this again and I am sure I will, I am having a blast.
I am torn, go with a donor or source the engine and trans and the rest of what is needed on EBay or Craig's list like Tony has done. I will say I learned a ton tearing the donor down and freshening the needed parts.

[redfogo]

I went no donor. I spent around 4-6k for all the Subaru stuff. The most expensive parts: JDM EJ207 has 37,000miles(60k), and new 06 WRX 4/2pot remand calipers(around $800 on rock auto). Everything else can be found at your local junk yard or ebay for cheap.

The reason I like this way better, there is no room taken up by a donor, no need to take apart a donor, and I could get a low mile JDM STI engine. The thing for me though it seems silly to reuse most of the Subaru parts if you buy a high mile donor. I really never see low miles on any Subaru these days.

I didn't want to reuse any of the hydraulics for the breaks or clutch. Most parts are fairly cheap and 100,000mile brake lines, master cylinder, calipers, clutch, flywheel, fuel pump, fuel level sensor, etc isn't worth the effort to reuse. Plus half the time the parts are all rusted and look ugly.

[Cnight]

Thanks for the input guys. I'll most likely go the donor route as I want to drive the car and see what all needs worked on prior to tearing it down. That way I can fix it as I tear it down instead of finding issues after the car is s completed.

Another question. I can use an outback wagon as a donor right?

[STiPWRD]

Double check the compatibility first, I don't think the Legacy outback would work. The kit is designed to work with:

02-07 Impreza RS/WRX (sedan or wagon)
04-07 Impreza Outback

[Newkitguy]

if you search hard enough you can find some really good deals at auctions and damaged cars. truth be told i'm probably one of the few that got my donor "dirt cheap" and ended up scoring on some aftermarket things on it. My donor cost me 1800 and the seller took everything apart minus the wiring harness. come to find out the car had aftermarket injectors, upgraded turbo, external wastegate and up pipe. I was originally going to jump head first into a GTM as i'm a corvette guy BUT this was too hard to pass up.

[Coolspot]

Double check the compatibility first, I don't think the Legacy outback would work. The kit is designed to work with:

02-07 Impreza RS/WRX (sedan or wagon)
04-07 Impreza Outback

Why only 04-07 Impreza outback? 02-03 are not compatible?

[STiPWRD]

Why only 04-07 Impreza outback? 02-03 are not compatible?
I'm just quoting the build manual (Appendix I), the 02-03 outback is not listed. It may or may not be compatible, you should check with FFR.

Edit: the 02-03 impreza outback is most likely fine, I'm pretty sure it's pictured as the donor disassembly vehicle in Chapter 2

[Bob_n_Cincy]

For my 2 donors, I went with a 2004 Forester XT and a 2005 Forester XT. Both with around 100k.
Same engine as an 04 STI but with a smaller turbo. $2500 and $2800 salvage auction. Usually 1-2k less than a wrx.
The extra parts don't sell as high as a WRX.
Happy with my decision.
Bob

[nkw8181]

There is a spreadsheet/thread out there that shows what will and won't work. It's been around since the car came out. On my phone or I'd go find it now

[TrickyPete]

I'm just quoting the build manual (Appendix I), the 02-03 outback is not listed. It may or may not be compatible, you should check with FFR.

Edit: the 02-03 impreza outback is most likely fine, I'm pretty sure it's pictured as the donor disassembly vehicle in Chapter 2

I used an 02 impreza outback as a donor. Only things I didn't use from the donor were the seats brake pads and rotors. I'm going to replace the steering wheel as well. I did notice my brake calipers in front are larger than a WRX's but the rotors are smaller. Unsure if that's an advantage or disadvantage.

[Cnight]

Thanks again guys. Got an 818C specific question. How hot does it get in the cab from engine heat and stuff? I've looked through some of the threads n here but haven't found a decent answer yet. I'm not going to be taking trips with it but may take 1-2 hour drives or longer at times.

Also how much work is it to install an a/c system?

And is it possible to use power steering or does engine compartment not allow for a power steering pump? I suppose electric power steering would be an option.

[jcpresto]

In my opinion you don't need power steering. I've not seen many others do this, but in my 818C I'll have full heat and A/C utilizing all the donor components. I don't think many of us have an understanding of heat in the driving compartment. I've opted to just install it incase I need it. I have a full rolling 818C and starting AC heat next week as well as engine installment.

[AZPete]

Most guys are not installing power steering, but I did. I just added longer hoses to the donor system, about $90. I like the power steering for turning at low speeds, like parking, and it adds dampening. The 818C is so new that nobody knows about heat yet but I live in the Arizona desert so I need A/C! Jcpresto says he will use all the donor HVAC components so maybe he has figured it out. I tried the donor HVAC unit but it was WAY too big to fit into the dash or into the nose section, so I bought a Vintage Air system minus the compressor. I haven't had the system charged yet so I can't say it works with the donor compressor, but it should. I've got ABS, cruise control, CarPlay and a backup camera so I should be able to get the A/C to work. I need is more garage time!

[jcpresto]

I should clarify! We have the entire donor system and will began to mock it up this week. I'm approaching this first as its free in my mind. If we run into fitement issues we have determined the vintage air unit for ac/heat/defrost that's fits. Among that we are also running 295 tires in the rear with a built 5 speed PPG gears in hopes to put down our ~440 RWHP motor. I have a friend That builds many custom vehicles for SEMA so changing the rear body should be easy. We have also modified much of the rear to allow the wheels to be tucked in as much as possible.

[nkw8181]

My shop said when they tune mine that he will cap the rwhp at 400 because the other car they tuned put down 322 and was crazy. I'm pretty sure 440 would be possible on mine but I have a feeling it may be a bit much. Check this out.

http://thefactoryfiveforum.com/showthread.php?16407-So-you-want-a-400-RWHP-818-huh

[jcpresto]

It will be interesting to see how it drives. We are tunning boost by gear so we can adjust it down if needed. Thats why we also are putting sticky 295 tires out back and using a different gearing in the transmission to produce more top end per gear aid in better traction. The feedback from driving should learn a lot. Our last car was a Porsche Boxster having a 3.8L 911 swap and meth injected turbo system from TPC racing. We put down 472 to the tires with 2800 lbs and it was very drivable and very fun! I have a full dynamat car and assuming with coupe top that it will be 2200/2300 lbs.

[wallace18]

The weak link IMO is the trans with the turbo engine. Spend the money and get an STI 6spd. Your wallet will be happy in the end. N/A the WRX trans will live better IMO.