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alxdgr8 03-04-2014 03:44 PM

VW/Audi 07K (2.5L 20V I5) Swap Thread
1 Attachment(s)
WARNING: This thread may contain non-conforming material to purist's. But remember, the 911 guys think our cars are VW/Audi anyways.

I've started this thread to track my progress on swapping this engine into my 968 and to serve as a reference in case other want to also.

The "07K" is a 2.5L 20-valve inline 5-cylinder engine from VAG. It's most commonly found in the VW Mk5 and Mk6 Jetta/Rabbit/Passat. A turbocharged and direct-injected derivative is also found in the Audi TT-RS. The cylinder head was developed from the Lamborghini V10. The indirect-injected cylinder head has VVT on the intake cam. Compression ratio is 9.5:1 on the N/A motor, 10:1 on the DI turbo motor.
The 07K is completely different from the earlier Audi 20v I5's. The number of cylinders and bore spacing is pretty much the only thing they have in common.

Another overview in it's stock form:

This engine is only used in the North American, South American, and Middle Eastern markets, as the replacement for the inline-four naturally aspirated 2.0 litre 8v.
parts code prefix: 07K
engine displacement & engine configuration
2,480 cubic centimetres (151.3 cu in) inline five engine (R5/I5); bore x stroke: 82.5 by 92.8 millimetres (3.25 in × 3.65 in), stroke ratio: 0.89:1 - undersquare/long-stroke, 496.1 cc per cylinder
cylinder block & crankcase
GJL250 grey cast iron; two-part oil sump, die-forged steel crankshaft with six main bearings, water-cooled oil cooler
cylinder head & valvetrain
cast aluminium alloy; four valves per cylinder, 20 valves total, low-friction roller finger cam followers with automatic hydraulic valve clearance compensation, chain-driven (relay method, using two simplex roller chains) double overhead camshaft (DOHC), variable intake valve timing
cast aluminium intake manifold, single throttle body with electronically controlled 'drive by wire' throttle butterfly valve
fuel system
common rail multi-point electronic sequential indirect fuel injection with five intake manifold-sited fuel injectors
ignition system & engine management
five individual direct-acting single spark coils with longlife spark plugs, Bosch Motronic engine control unit (ECU), secondary air injection during cold start phase to reduce emissions, single knock sensor
exhaust system
one-piece cast iron 5-into-1 exhaust manifold, ceramic catalytic converter, two heated oxygen sensors (three when equipped with California emissions) for permanent lambda control
DIN-rated motive power & torque outputs, ID codes
110 kilowatts (150 PS; 148 bhp) @ 5,000 rpm; 225 newton metres (166 lbf·ft) @ 3,750 rpm -- January 2005 (BGP/BGQ/BPR/BPS)
125 kilowatts (170 PS; 168 bhp) @ 5,700 rpm; 239 newton metres (176 lbf·ft) @ 4,250 rpm -- from May 2007 (CBT/CBU)
By the numbers comparison of the 07K vs 951 engine:
07K is the same displacement, 2.5L.
07K has one more cylinder, I5 vs I4.
07K has 12 more valves, 20v DOHC vs 8v SOHC.
07K is an iron block with cast aluminum head vs all aluminum (alusil) for the Porsche.
07K can have a forged crank (early ones or TT-RS) with cast rods and crank vs the all-forged (crank/rods/pistons) Porsche.
07K can be had for <$500 for a complete engine with <50k miles vs $1k+ and lots of miles.
07K is 6.5" shorter from bellhousing to crank pulley.
07K block is 2.5" shorter.
07K is 4" longer on the rear of the motor above the bellhousing due to the timing chain/etc.
07K has VVT on the intake came vs one cam with none.
07K can rev to 8500rpm stock where the 951 doesn't live long at 7000rpm.
07K weighs ~20-30lbs lighter overall with turbo/manifolds/clutch/etc. AND the 07K places much of it's weight at the rear of the motor due to the cam-chain assembly and jackshaft driven accessories.
07K can make 400whp on stock everything (including cast crank/pistons/rods) vs about the same on the 951 engine (at higher boost and higher octane fuel on the 951).
07K cylinder head flows 230cfm (x5 cyl) stock vs 180cfm (x4 cyl) stock on the Porsche.
A plug-n-play standalone ECU will soon be available for the 07K harness where nothing of the sort is available for the 951 (and the 951 suffers from a 25 year old fragile degrading harness). It'll cost about the same as a MAF kit for a 951.
07K has a trigger wheel built into the rear main seal that's been tested to be reliable to over 9400rpm. Much better than the flywheel mounted sensors on a 951.

Engine year differences:
These are the early motors found in MY 05-07 cars and are 148hp/166ft-lb. They have the early style timing chains which can have problems if you follow the VW prescribed 10k oil changes. If you treat them like a performance engine and change your oil at more frequent intervals you'll be fine. Forged cranks were randomly sprinkled into production with these engines and you can't tell without pulling off the pan. A forged crank has a much wider flash line than a cast crank. It might be possible to confirm cast or forged crank by the part number on the flywheel mating surface but this is only speculated. These engines have a 6 bolt attachment for flywheels.

These are the later motors found in MY 08+ and are 168hp/176ft-lb. These have an upgraded timing chain and use an 6-bolt flywheel attachment on the crank. No forged crankshafts are known to exist in these motors, however the forged crankshaft for the TT-RS drops right in. The TT-RS crankshaft can be bought new from VW/Audi for $1100-1300. The TT-RS also has an 8-bolt flywheel attachment.

A few more differences depending on the year, but most won't matter for this swap:

From 2005.5-2007 Four engines were used. All were 150 HP.
BGP (federal emissions) Jetta/golf, BGQ, Cali emissions- jetta/golf, BPS, federal emissions beetle, and BPR cali emissions beetle.
From 08 to 10, The BPR and BPS beetle engines were the same HP and specs.
From 08 the 2.5 is bumped to 170 HP from software and intake manifold upgrade
In 09, MAF was dumped for MAP system. ( except early 09 sportwagen, it had maf)
08-13 engine codes are CBUA (cali emissions) and CBTA (federal emissions).
In '11, The exhaust manifold uses individual header tubes and a variable oil pump. It uses a high/low function. It's default to high until 1000 KM, then under 3k rpm ish it uses low pressure and above that it uses high pressure.
All engines : Cali emissions uses three oxygen sensors while federal uses two.
When the redesigned intake manifold came about in 08, the runners are shorter and the powerband increased to a higher rpm.
All 2.5's use variable intake cam timing
All are 9.5:1 compression.
All use cylinder 5 as top dead center instead of 1.
Parts needed for swap:
-Motor mounts. This gets more complicated as the block wasn't designed for transverse mounting. Iroz Motorsport has developed mounting that part of the oil cooler mounting and provides connections for external oil filtering and cooling. Mounts will be adapted from the Audi application to the Porsche.
-Bellhousing adapter. This can be done several ways, but I'll most likely be modifying a VW bellhousing to fit the torque tube instead of modding the Porsche one and adding an adapter plate.
-Flywheels and clutch/PP. Depends on how you do the bellhousing, but parts are available for whichever route you go.
-Intake and exhaust manifolds. These will be custom and will most likely be different than the Audi application due to clearance issues with the strut towers.
-Turbo and IC piping. Depends on your power goals and exhaust manifold. No antique KKK stuff will be used here. Plenty of room for a large FMIC and radiator.
-Custom downpipe. Should be able to make this hook up to the 951 exhaust locations.
-ECU. A plug-n-play VEMS ECU option is coming soon for ~$1300 and will use the factory 07K harness. Build your own harness or an adapter harness and you can get the generic VEMS ECU for $750. One could also use the stock motronic with a tune if desired, but that would require a lot more work.
-Custom PS and pulley system. Iroz Motorsport has this developed. Once could also use an electric PS pump.
-Oil pan TBD. The stock oil pan did not clear the subframe in an Audi application thus Iroz had to design one. I have not determined if this is the case with the Porsche. If so, the Audi oil pain will most likely work for this application too.
-Rods and pistons if you desire more than 400whp.

There are a few unique costs to this build, but much of the parts would be required for a 951 engine build of the same caliper. You can offset the unique costs by selling the 951 (or 968) engine due to the much lower core engine cost of the 07K.

Here's the world's first longitudinal 07K in an Audi Ur-Quattro built by my friend Hank Iroz of Iroz Motorsport in Las Vegas. Motor is a build 07K with HTA3582r.

Solid line is the 07K with HTA3582r at 17.5psi. Dotted line as an Audi AAN 2.2L I5 with a Billet K26 at 31.5psi. Both on E85.
Attachment 1205098

And at 25.8psi and running out of fuel on 1000cc injectors with 85psi base pressure.

Progress is still being made with VVT control via VEMS standalone. Better spool is expected as more tuning of the VVT is done.

Aftermarket cams are in development right now, but not released. The stock cams get pretty bad above 7000rpm. With upgraded cams and springs the motor will continue to make power up to 8-9krpm with no problems. You'll need a 67mm turbo to flow enough at those RPM's, but you'd have pretty much an 850whp setup.

If E85 isn't readily available (like in Seattle where the nearest station is 45 min away) then these still have plenty of potential on pump gas. Here are some charts from the TT-RS motor with a GTX3576r which is close enough for comparison.

alxdgr8 03-04-2014 03:49 PM

1 Attachment(s)
My Engine:
I purchased a CBU 07K out of a 2012 Jetta with 35k miles on it. Cost was $600 with the wiring harness.

Attachment 1205097

I've decided to go the slightly more expensive route by going with a later engine. I'll most likely purchase the forged TT-RS crank later. This will give me the benefits of the updated chain drive and 8-bolt crank instead of 6-bolt which should make my clutch options cheaper and stronger.

I'll probably keep the stock cast internals and be limited to 400whp for the initial setup. This will allow me to figure out all the kinks first and then I'll build the motor with the forged internals and crank.

The front of the piece of wood is approximately where the front of the 07K would sit in a 944/968 engine bay. 6.5" further back!

Hacked 987 03-04-2014 03:59 PM

THIS I am interested in following.

Much more interesting than an LS swap :)

mikey_audiogeek 03-04-2014 05:20 PM

Great swap!!! I have been looking at this over the last few weeks as well.

Worth mentioning another couple of advantages:
- the 07K has the same diameter clutch as the 944 so the combination of a 944 clutch and an 07K pressure plate should work well.
- no need to modify the brake master cylinder arrangement
- should sound AWESOME
- the motor is half of a Lambo V10 so we continue the tradition of using "half a great engine" in our 944's!

DLS 03-04-2014 05:21 PM

i will follow this with big interest :)

slap929 03-04-2014 05:22 PM

Very Interesting. Please continue posting :corn: and thank you.

mikey_audiogeek 03-04-2014 05:23 PM

Also some great gains are available on this motor even without turbocharging: the stock intake manifold is restrictive and one supplier had dynoed a new intake at +48bhp with an ECU reflash. Plenty of people getting 200 horsepower at the wheels without cams or turbos...

alxdgr8 03-04-2014 05:43 PM

Originally Posted by mikey_audiogeek (Post 11185805)
Also some great gains are available on this motor even without turbocharging: the stock intake manifold is restrictive and one supplier had dynoed a new intake at +48bhp with an ECU reflash. Plenty of people getting 200 horsepower at the wheels without cams or turbos...

True, you could even make some FSI pistons work for higher compression to get even more out of it N/A.

Paulyy 03-04-2014 05:52 PM

Just put a gtx4202 and be done with it ;)

cannot wait to see this happen

333pg333 03-04-2014 05:56 PM

How does it sit so much further back? Is the motor itself a lot shorter?

reno808 03-04-2014 06:01 PM

This is awesome.... Finally a real build. BTW this is nothing new for the ppl in Northern Europ. They do this all day along.
Keep posting. i might even put this on a 924 shell i have just begging for a something.

Dougs951S 03-04-2014 06:14 PM

Amazing..watching this closely.

alxdgr8 03-04-2014 06:14 PM

1 Attachment(s)

Originally Posted by 333pg333 (Post 11185906)
How does it sit so much further back? Is the motor itself a lot shorter?

The motor is 6.5" shorter from the bellhousing to the front of the crank pulley (due to the timing belt/balance shaft belts and serpentine). The physical block is 2.5" shorter. It's a timing chain motor with the assembly at the rear of the engine. This leads to there being a 4" overhang above the bellhousing. Another thing that helps with length is the belt setup (ignore the chunk of metal on the top/front of engine, it's for the transvere mounting; in a longitudinal setup the pulley is the furthest thing forward)

Attachment 1205094

Originally Posted by reno808 (Post 11185919)
This is awesome.... Finally a real build. BTW this is nothing new for the ppl in Northern Europ. They do this all day along.
Keep posting. i might even put this on a 924 shell i have just begging for a something.

They've done the old Audi I5's but not the new ones ;) In fact, they don't even get the VW I5 in any cars over there. My friend is actually shipping motors over to them.

alxdgr8 03-04-2014 06:25 PM

And in a AWD Rabbit with a Precision 6765, 811awhp

333pg333 03-04-2014 06:56 PM

This has some merit. Had I not gone so far down the road with these i4 builds I would have certainly given this some serious thought.

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