A4 Ti20

[quattrofrog]

Continuing from my previous projects thread... this thread is to document the build of a AEB/ABA 2008cc 20v turbo engine for my 1996 B5 A4 quattro. I need to start fresh and a new thread is as close as I'm going to get to just that. My Sedan is now converted to 034efi IIc, with complete instrument cluster functionality.

I'm building the car primarily for HPDE use. Eventually I'll add a cage, harnesses and race seats. I don't really need this kind of power IMO, but I can always run less boost for a less aggressive car for when I need to focus on my driving rather than being playful and flexing the muscle. The saving grace of this car is the published factory weight of ~3226lbs, I've removed some of that weight and shifted some of it rearwards. Post engine swap I expect the car to have an improved weight distribution which should improve the neutrality of the car's handling. I'm hoping to see a Phase 1 track weight of 3100lbs or less which provides a minimum power to weight ratio of 8.86lb / hp with a ~350hp w/ 93oct ... or as low as 7.21lb/hp at ~430hp w/104oct. We will see what the actual numbers are once the swap is complete, but it is sufficient to say that the car will be quite rapid. The Porsche 997 turbo has a power to weight ratio of 7.88lb/hp. My RPM limited top speed at 7200rpm is 174mph for 5th gear, given the ~.31cd and ~2.1m^2 frontal surface area I likely have to work with... I should have just enough wheel HP to reach that sort of speed.

Phase 1 (in progress)

AEB Engine Block bored to 83mm
ABA Crankshaft (forged 92.8mm)
AEB Cylinder Head fresh from Audi of America
Coil cover 034efi
ALT Head Gasket
AEB Main Bearing bolts
AEB Rear Main Seal
AEB Front crank flange/seal
AEB Sump gasket
AEB timing belt kit
AEB Crank Gear
AEB Oil sump
AEB Oil pump
AEB Oil filter bracket
AEB Coolant flange
AEB Radiator
AEB Upper rad hose
AEB Lower rad hose
AEB Water pump
AEB Coolant Jacket
AEB Intake Manifold
AEB Intake Mani Gasket
AEB Throttle body Gasket
AEB Fuel Rail
AEB Injector Seats
AEB Throttle body
Flywheel: aasco 1.8T
Clutch: South Bend Stage 4 OFE / Sachs Race Engineering PP
AEB Vane Pump
Turbocharger: Garret GT2871R (743347-0002)
Turbo inlet pipe: Nissan S14/ Custom
Intercooler: Precision Turbo
Intercooler plumbing: Custom
bypass valve: Tial BOV
AEB Accessory bracket
1.8 20v NA snub mount bracket (for vehicles without A/C)
AEB L/ Engine Bracket
AEB R/ Engine Bracket
Exhaust Manifold: PES T28
Downpipe: 3" Custom
Exhaust: 3" Custom
AEB lock carrier
Hall sender ring: 034efi
Spark plugs: Bosch F6DTC
AEB Hall sender
AEB Ignition coils
AEB Alternator
AEB Starter

Phase 2 (when 350-430hp gets boring)

Main bearing studs & Engine Block Girdle
Larger turbocharger & Exhaust Manifold
Lighter valvetrain components
cams (1.8 20v NA intake cam perhaps)
raised rev limiter
larger intercooler
larger throttle body

Block Specs:
Bore 83.0
Stroke 92.8
Rod Length 144.0
Wrist Pin Dia 20.0
Rod/Stroke Ratio 1.55
Displacement 2008.0

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Pictures will be found here http://qfrog.smugmug.com/gallery/2062507
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[Wizard-of-OD]

Why?Go ABA 20V....Will save you cost on:
* Custom intake manifold (chopped AAN or chopped AEB welded to 9A lower)
* Turbo manifold (if you want anything bigger than a K03)

[quattrofrog]

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20v selected, 16v no longer being considered
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Wiz

I did consider the ABA 20v.

The AEB head is more expensive and is part of an engine which has sludge and timing belt issues due to maintenance manuals containing misleading information.

The 16v Turbo Manifold 034 makes should work http://www.034motorsport.com/images/thumbs/thumb-16V_MANIFOLD_100_94.jpg should work nicely as it keeps the turbocharger centered which is a mild rearward shift from the stock manifold. If anything this provides me with more room for an air filter. The ATP manifold shifts the turbo even farther back than the 034 piece. In stock form the 1.8T manifold places the turbocharger forward to allow for a catalyst between the turbo and downpipe. Upon inspection of my father's 1.8T A4 There looks to be plenty of room to shift the turbo rearwards using a testpipe. Should the stock 034 manifold not work I could always beg to have a 034 manifold assembled with a forward shifted T3/T4 flange.

[Wizard-of-OD]

unless your getting the 16v head new,your going to have to overhaul it just like the 20v head.2 years ago when 20V parts were rare and "expensive" I would have said yes jump right onto a 16V head but today,I would seriously advice that you reconsider this simply because there are alot more parts available and the A4 came stock with a 20V head.
Alot less reconfirguration in that department.
As for turbo manifolds,there a whole heap out there that offer a centred t3/t4 flange.

[quattrofrog]

____________________________________________________________________
20v selected, 16v no longer being considered
____________________________________________________________________


A 16v head costs less than AEB head does and with what looks like only a slight reduction in flow. I have access to an AEB core but that route would still cost me $1500 for a completely stock reman head from Audi. A 16v head of good origin and in good condition rebuilt by my machine shop with new cams, lifters and valve seals is likely ~$800. I don't think i can come close to that with an AEB head. I really don't want to buy an AEB head on ebay, I have a phobia of 1.8T engines thanks to my experience at work. I've seen 20 bent valves, failed cam tensioners, sludged heads, scored bearing caps... They're becoming cheaper because the vehicles with them are leaving the roads due to accidents and failed engines which result in repair expenses exceeding the value of the car to the owner. I think I've seen just about all the possible scenarios at work. The 1.8T is a great little engine but entirely too many examples are not maintained properly and that is going to be the demise of many a 1.8T.

[Wizard-of-OD]

AEB Core + Stock cams - $150US
Aftermarket springs & retainers from 034 - 495
Aftermarket valves - 400
Put it all together and you have a nice race prepped head for under 1500.working @ the dealership doesnt mean you know where to get the best bang for buck parts
To get Stock 1.8T valves now are a joke because all those with stock are going aftermarket.

[quattrofrog]

____________________________________________________________________
20v selected, 16v no longer being considered
____________________________________________________________________

In light of the suggestion made by wizza I've been busy pricing things out for the various swap and there are several routes I can follow to a potent 4cyl turbo. There are aspects I like about all three of these potential courses of action. I'm weighing advantages / disadvantages with cost, risk and effort.

Here are my thoughts so far...

ABA 16v build

Advantages
· Piece assembly/ acquisition method
· No expensive individual components
· Proven with references to completed transverse
· 2.0L displacement
· Forged crankshaft
· Safe potential 400+ HP
Disadvantages
· Unknown fitment of exhaust manifold from transverse application
· Custom intake manifold required
· Unknown cooling, vacuum, breather system arrangement/integration
· Single custom bracket required
· Unknown exhaust downpipe fitment (angles/chassis)
· Unknown block/head height combo fitment under hood


ABA 20v build

Advantages
· Piece assembly/ acquisition method
· Proven with reference to completed engine in B5
· 2.0L displacement
· Forged crankshaft
· High flow cylinder head
· New bearings, seals, rings in engine
· Safe potential 400+ HP
· Forged rods & pistons
· Cooling, vacuum, crankcase breather, systems.
Disadvantages
· Rebuilt head from regional vendor without prior history
· Single custom bracket required

AEB swap

Advantages
· Complete engine assembly available
· Quick
· Direct swap/ bolt in
· High flow cylinder head
Disadvantages
· Expensive initial purchase
· 1.8L displacement
· Cast crankshaft
· Possible sludged engine history
· Possible broken T-belt history
· Safe potential is limited ~350hp
· Stock rods/pistons


I have more research to do before I can make a final decision and subsequently make a purchase.

[GTIVR62801]

I'm going to have to vote ABA 20V on this one, its the easiest choice with best durability IMO.

[SilverCQ]

i say go aba/20v, if i get the itch farther down the road i might as im basically running all 1.8T electronics already......
i only did the 16v b/c i already had it, and i thought it'd be neat

[quattrofrog]

I appreciate the input guys.

[Wizard-of-OD]

[quattrofrog]

I may be able to pickup an AMB code head with <40K through work for a modest sum. I'll know tomorrow if the AMB head is going to happen. Failing that a friend has an AEB head in need of new valves and a rebuild... another friend has an AEB head with a cracked casting and a good set of valves. A+B= AEB?

The PES manifold is a nice piece and if I go with a GT28R or GT28RS I'll certainly give it consideration. However I have temptations of Holset HX35W or some other largantuan turboladder with a T3 flange. So i may have to go with a ATP manifold.

[quattrofrog]

Cyl head No. 1 had scored cam bearing caps... that wont do. There is another head at work which I'll examine tomorrow. Cyl head 2 is likely in better shape, failing that I still have the AEB heads which will cost more than the AMB head.

That PES manifold and a GT2871R with a T25 hot side might be a suitable combination for my target HP of 400 crank. I don't think I'll be happy with much under 400hp given the expense of such an engine.

[GTIVR62801]

That Holset is calling your name Phil....but if you forgo that for a ball bearing Garrett I won't get mad at you.

[Wizard-of-OD]

Holset?Man go with what is PROVEN!

[SilverCQ]

whats the big thing with holset turbo's anyways, i never hear anything about them except on here.....aren't they diesel truck turbos?

[GTIVR62801]

[SeStone]

[SilverCQ]

well now im all curious, what kind of holset did tom ritt use? i see a bunch of hx35's on ebay, how would they fair on a 4 cylinder?

also, they're flange looks like a dual scroll t3? would it bolt to a standard t3 flange, or does it require its own flange....

tia

[SilverCQ]

[derracuda]

they have a different flange than a T3

[SilverCQ]

know of anyone who makes/sells the flanges?

[derracuda]

not that i know of. i started making mine when i changed minds about keeping the 10v in my 4kq, so i have a partially made holset flange

[SilverCQ]

lol, you dont have any idea what turbo tom ritt was running do you? hx35? i've been reading all sorts of stuff on one of the dsm turbo's i guess they really like the holset's, however, a lot of the information im looking for i cant find....still searchin though

[quattrofrog]

http://dodgeram.org/tech/dsl/FAQ/turbo_faq.htm

In recent discussion with Tom I think he said his is a HX35. IIRc he said no more than 12cm hot side turbine. There is a HY35 which I believe spools quicker but it has a peculiar forward facing outlet which I dont think is compatible with my engine bay.

They spool quickly on small engines because a 6L turbo diesel straight six doesnt rev particularly high. Lets say 4.5k limit with a guestimate of spool by 1.2k... 6/2= 3..... 3*1.2k = 3600rpm spool with a two litre engine.