914 Time Attack Engine Swap: VW 1.8T vs Subaru EJ20

Hey GRM,

I am close to starting a new race car project based on a 914. The goal is time trials with ~10 lbs/hp for NASA TT3. So I have decided that an engine swap makes the most sense to get me to my 200-220 whp goal and allow for future growth, i.e. more power. Anyway, I know both the VW 1.8T in longitudinal configuration with 5-speed have been swapped into 914's with success along with Subaru EJ20's and EJ25's with the 5-speed transmission converted to 2WD mode. Where I need some help from some more experienced people is if either engine offers any inherent advantages toward reliability on the race track as a dedicated time attack powerplant. My goal is to have a powertrain that can run all day at the track and be drivable, more so than making gobs of power.

I like the VW 1.8T because I'm VW/Audi/Porsche fan (hence the 914 chassis) though I am concerned about keeping it alive on track since I haven't been able to find a lot of information on how well the stock oil pan holds its oil. I know I could possibly build a custom oil pan since there don't seem to be any for the longitudinal mounting, but will that be enough? Or if I want to use the 1.8T I'd be better off with a 2-3 stage dry sump? 

I know the Subaru motors are used a lot on track and need some oil pan and pick-up modifications before they can be abused on track but is that all they need? The Subaru also seems to benefit from more support for racing with gearbox/differential upgrades and engine upgrades specifically for the task when compared against the VW 1.8T.

As a side note, I narrowed my swap options down to these two based on the criteria of having a complete powertrain that had its own transaxle (so that swapping didn't involve adapters and custom flywheels), turbocharged (because BOOST and for ease of tuning a flat hp curve), proven to fit in 914, and "light" (I know these aren't the lightest but they also aren't the heaviest. Also, either option would be ran on a standalone ECU (yet to be determined) so that I can easily send all the engine data to a logger for when its on track.

Cheers for the opinions and information!

Luther

I really like the ej20 in my wrx wagon. Very torque-y for its size and the aftermarket is huge for them.

At one time you could get the twin turbo ej20 for around $500.

This comes down to: Which engine fits better and or is easier to work on?

This sounds like a job for a EJ25 head swap hybrid. 

A place here in Alpharetta ga. builds them to 600hp /audi vw/ and puts them in 924's GRM did a write up on them.

@ GTXVette: Are you talking about MotorWerks? I should reach out to them and ask what they do to prep the 1.8T's for race duty.

@AnthonyGS: I hadn't thought much about that, I wonder how much lower the Subie engine is over the VW. By eye it would look like the crankshaft of the Subie sits higher due to transmission than the VW would; but it also has the rest of the engine lower.... this is definitely worth investigating further.

@noddaz: I think they are likely about equal, each one having their own difficulties but I have seen multiple builds with each engine, though the 914 crowd tends to favor the subie, I think due to it being a boxer motor and thus a "natural" fit.

I appreciate all the feedback, keep it up 

For me the geaerbox setup is most important .....

that stock gears will work for the track you plan on running , that an extra gearbox is cheap and not too hard to switch over and that the shifter feels right :)

Horsepower is easy , you will probably have more than you can handles , but getting the HP to the ground will be more of a problem......

You didn’t put a budget limit in your post so I’ll put this out here......911 motor.

Fair point I didn’t set a budget. I think realistically I’d like to stay under $2500 for engine and trans and any reliability upgrades or rebuilding due to mileage.

Looking at the local pull-a-part I’ve found decent donor Passats some with manual trans that I could pull the whole thing for under $500, so it’s hard to look at $5k+ 911 engines.

Yes MotorWerks

This is definitely one of those "it would be cool if" and not one of those "I have the skills and time and energy to do this myself" ideas, so, grain of salt.

Early Boxsters seem to be getting cheapish.  Like $5k or less for higher mileage, good running, manual trans cars.  What about one of these as an engine donor?  The engine has to come out of the Boxster anyway so an IMS bearing change at the time wouldn't seem like such a hassle.  

I don't know what the engine management would think about being wrapped up in a 914 and the original HVAC and seat belts and lord knows what else is missing.  I don't know about the aftermarket potential to bring these motors up on power without spending a lot.  But the idea seems sound for miles away.  Right?

I would think the Subaru engine would work better as it’s a boxter engine just like the engines the 914 came with originally. Heck porsche is using water cooled flat 4s in the boxster and cayman now.

I’ve thought about the Boxster motor but felt the added complication didn’t add much value, but I agree it would be cool idea for a resto-mod or pro-touring style 914 build!

I’m mostly concerned with any inherent weakness’s with the 1.8T vs the EJ20 when abused on track with “stage 1” power levels. Both are cool, both fit, so is race track reliability any different between them?

I gotta agree, go with the engine that fits better.  1.8T motors are extremely stout as long as the oils been changed.  Suby motors have issues with piston ring lands, oil pick up tubes and the like.

I have a passing admiration of the 914, and have bench raced them in my day dreams many times.  I also have an affinity for those beautiful boxy Swedes.

It's a bit of a stretch, but you could power your 914 with a Volvo Whiteblock, and still kind of be in the Porsche family, since Volvo got an assist on design and tuning of it's new, all aluminum, modular, 5 cylinder from Porsche back in ~'92.

T5-R 914 sounds pretty awesome to me.

I want a naturally aspirated 13b 914. A built high-strong engine that brap crackle and pop.

yupididit said:

I want a naturally aspirated 13b 914. A built high-strong engine that brap crackle and pop.

Saw an old Beetle with a rotary.. Sounded great. Owner complained about too much work.