My peppy/fuel efficient passat build

Discussion in 'Car Journals/Projects' started by budsdubbin, Dec 7, 2016.

  1. budsdubbin

    budsdubbin Posting- God

    So I have been extremely busy with home life, job and small hurdles along the way.

    THE STORY: 2 years ago you couldn't catch me looking into owning a passat. I hated the body of most passats. Until I stumbled onto the most comfortable and fun daily I picked up at a great price. Its a 2004.5 b5.5 passat GLS 4motion 1.8t 5spd with 85k barely any .... other than the front end sagging a bit from the previous owner(frame rails bent down), I drove the hell out of it all year long. Its been an absolute unstoppable force in the snow.

    THE BEGINNING OF THE NEVERENDING STORY BUILD: Its been completely stock up until I picked it up and honestly it felt slower than a Prius on stock tune. So I HAD to build my own custom tune from scratch with reliability and max MPG in mind. Removed the secondary air pump/random vacuum lines to clean things up and a little TLC in maintenance. It was a blast driving all year long. I calculated 26-28MPG's a couple times but I plan on getting it over the 30 mark by next spring.

    Last year before spring I smoked a dear on the way to work @ 45mph... Driver front headlight was damaged along with the radiator, radiator support, grill and hood. So I found a donor parts passat to fix it. Fixed it and almost 2 months later on my way back to buffalo from Albany I smoked another deer at 80mph. I tryed to patch up the one busted turbo cooler line and limping my way home from rochester. went about 10 miles from the stop on the 90 and boom there must have been a big pocket of air. The coolant temp jumped to redline in a couple seconds and the headgasket went. My luck hasn't been great lately but thats what I get for trying to macgyver myself home lol.


    So when I do things I am a bit anal so instead of just replacing the gasket I had the head decked, I lapped the valves and freshened everything up. I'm not sure if I have picks of the head being torn down but if I find them I'll post them.


    I couldn't stop there because I had a feeling the ko3s was on its way out and I was right. Compressor wheel kissed the housing but not enough to junk it. Shaft play was a bit outside my comfort zone. The thrust bearing almost gone(usual wear when shaft speeds are up). So I ordered a rebuild kit and 4k miles its snug as a bug.

    So my donor car was usless for most of the body damage because most of the parts I already used. Anyways couple trips to the junkyard and its back together. Rattle canned the bumper, fixed fender/pillar rust areas and blended the paint. I'm pretty happy with the results.


    Ok so next up is to continue improving it because thats just what I like to do.
    RoachinRay likes this.
  2. budsdubbin

    budsdubbin Posting- God

    To do list:
    Find an appropriate intercooler setup or replacement- My current one has oil cooked on the lower end tank which maybe why the turbo ended up failing faster than predicted. I've picked up an audi a4 intercooler but the core is smaller than the oem and I didn't pick up the hoses because I assumed it would bolt right up. Well the hoses on my passat are the metal/o-ring type couplers not the hose style on the audi. Input into this is welcome. I don't want to spend alot but a good sidemount would be nice. I want to stay away from gambling on a front mount that won't fit with the fogs.

    I'm bored lately so I'm really interested in making a hybrid ko4 to lower shaft speed and get more top end out of it. I can use a ko4-015 turbine (1mm larger than the ko3s) and housing with a compressor from a ko3s but if I'm going to get into machining I may as well try for a ko4-015 with a compressor from a ko4-023. Some use the compressor wheel from the ko4-023 (56mm) which is larger than the ko4 used in the (51mm) rs4 turbo. This topic has been beaten to death on the forums but I am not interested in making a cheap effort for maxxxxxxHPssss. I like building things and making them work. Worst case if I get lazy I'll just buy one of the ebay hybrids using the housings and replacing the internals with OEM seals and bearings. Manifold crack at the collector has been welded/repaired and smooth ported.

    catless downpipe, ebay knockoff forge piston style DV and air filter are here and ready to install
  3. lorge1989

    lorge1989 Posting- God

    unicorn status. I love B5.5 passats, the hatch on the wagon is huggggeeeee. Thats a seriously good find.

    If you are trying to something a bit different with the turbo, try an ebay source for the compressor wheel? Maybe a TD-04 with a modded turbine or exhaust manifold?
  4. budsdubbin

    budsdubbin Posting- God

    Well TD-04 would require oil, coolant line, downpipe and exhaust manifold mods. I won't get into that kind of mods on this car. I want OEM everything so that I don't have to chase my own tail with leaks and time consuming/knuckle busting labor. Bolt on swap is all I'm looking to do keep things simple and stay with KKK CHRA.

    ko3, ko3s, ko4-001, ko4-015,ko4-020, ko4-023,ko4-025, ko4-026 - compressor/turbine wheels can be swapped and will fit, depending on the wheel, machining of the housing may be needed. There have been some who have used a ko4-023 in the ko4-015 with some modification to the compressor housing (looked like a ko4-023 housing) and the stock ko3 housing to fit both wheels. I would like to find a ko4-023 compressor wheel and housing for modification. Obviously the inlets bigger so I'll need a TIP to fit it. Then find a ko4-015 hotside for a more simple approach. Believe it or not the 025/026 off the 2.7t have the same compressor wheel size as the ko3s

    If I have it my way using the ko4-020/015 exhaust I'll end up with:
    turbine - inducer 50mm exducer 42mm (stock 45mm,38mm)
    compressor - inducer 42mm exducer 56mm (stock 38mm,51mm)
    which could make for a 22-25lb/min flow rating

    If I want to do a simpler hybrid with little to no fab work I can use the ko3s compressor with the ko4-015:
    ko3s compressor is about 3mm on inducer and 1mm on exducer larger than the ko4-015

    second option is obviously less fun.
  5. lorge1989

    lorge1989 Posting- God

    Totally easier, I dont blame you for wanting to keep the factory coolant and oil lines.
  6. SloDub

    SloDub I got a Tetnis shot

    +1 on the winter beast aspect of this car! Keeping on this one...

    PS, this is one of the cars I flip/flop on regretting selling
  7. budsdubbin

    budsdubbin Posting- God

    Thanks guys!!! Yeah I hated all passat bodies but I took to this car because you don't find 5spd 1.8t 4motion passats normally and at a steal of a price. Its basically an audi a4 with a VW badge. More I drove it the more I loved it specially it being my first sedan with all wheel drive. I know the motor very well, I can fix it on the cheap and tune it to my liking.

    Well I ran into an issue this weekend with a flat. Put the passat back up in the air to repair the flat. Found that my driverside tie inner tie rod was ready to break free out of the joint. Good thing I bought a replacement inner/outer tie rod as a set. Replaced and fixed my horrible front end creak.

    Upgrades were sitting in my trunk so I said screw it.

    cheap ebay downpipe 45$ shipped. Install and fitment were rough. Rear o2 doesn't fit, bung for it is located on the wrong side which would make the sensor hit the firewall. So I zip tied it because I already tuned it out. With stock flex pipe it damn near hit my transmission mount(talking maybe 1mm of space) so I need to do some fabricating. Also pushed the exhaust less than an inch away from the prop shaft so I'm getting rubbing on low mph/heavy throttle.

    Ebay forge knockoff DV 25$- I pulled apart to inspect for potential issues. The piston didn't travel very smoothly. Seemed like they used thin whale blubber to lube the piston.... So I cleaned it and applied some synthetic brake parts lube, reassembled, now all good. Probably the best buy I've had for the passat.

    So far I can't complain because you get what you pay for. Other than the exhaust rubbing this car has definitely come alive more than I expected. PICs and more fun updates will be posted in the future...
  8. lorge1989

    lorge1989 Posting- God

    Even better, the B5.5s are actually more like half A4 half A6, so your passengers get killer leg room in the back and the hatch is huge! Good progress mang
  9. budsdubbin

    budsdubbin Posting- God

    wow that is something I didn't know/notice until now. Your right I do have plenty of room in the trunk and rear seats. I guess I haven't spent enough time back there to notice!

    had to turn the downpipe it didn't hit my transmission, prop shaft and frame. Isn't pretty but I was in a rush and don't really care for pretty on this thing.
    Cheap highflow filter (very flimsy on install but with a little TLC you can make it work)
    relubed DV
    Fixed up the welds/fitness gap on the DP for the hell of it. Cheap stainless TIG's like mild steel
  10. budsdubbin

    budsdubbin Posting- God

    Update: So my ko3s was on its way out 3 weeks after my rebuild. Good news is it wasn't the bearings or install that caused the failure. The compressor wheel had an inducer literally bend backwards from whatever made its way into the intake. So I did some investigating into hybrid ebay ko4 options and found a company that I believe manufactures frankenturbos and bought their ko4 with a bigger compressor wheel. According to their specs on the compressor it should have been smaller on the exducer but it was 3mm larger than what they stated on their website. Then I ordered a oem upgrade bearing kit.

    Now oem ko3s is about 50.1mm on the big end and the inducer is 36mm(KO3S has a bigger compressor wheel than the ko4). As you can see the compressor is 51+mm and the inducer is 38+mm. Which isn't much but its better than nothing.
    Now this next image is a huge reason why these ebay hybrids go so fast with high boost. The lower bearing set is what the ebay turbo came with. If you look you can see that there is only 1 oil feed and less contact area then the upgraded. Also the shaft bearing has no oil passages.
    Unfortunately I wasn't able to replace the seal on the turbine side because the diameter is larger and the machined spot for it isn't wide enough.

    Each of these turbos come with a data sheet confirming the center section was balanced on a vibration sorting rig. Which is pretty cool to see. So I tossed it in and gave it a shot. I had a feeling the wastegate spring rate would be higher but I wasn't sure how much. Ended up with well over 22psi (I don't have a boost gauge), and the car ripped but I don't have the fuel for it. Took it down to 18psi after I adjusted the PID. I'm really happy with my gamble even if it lasts me 1month I'll just put a larger billet compressor wheel which I also found available.
    Last edited: Jan 10, 2017
    JKaczor and RoachinRay like this.
  11. lorge1989

    lorge1989 Posting- God

    This is cool. Details on the company that you bought it from, pm me if you want.
  12. budsdubbin

    budsdubbin Posting- God

    "REV9" ko4 hybrid on ebay. It also came in a GODSPEED box so I think maybe godspeed is the parent company. Somewhat similar to what raceland did with its company branches or sublets. Now I havn't really done much investigating regarding the facts but based on the quality of the turbo and casting on the compressor housing it looks pretty damn close to that of a frankenturbo. There is a JTM logo cast into the compressor housing much like the FT logo.

    Now this isn't a fact so I'm not afraid to post it. This is only a guess on my part based on a visual comparison. If anyone has a bum FT they want to let me look at I can give a more thorough comparison.

    Anyways So this turbo is around the size of a ko3s/ko4-015 hybrid with a bit more on the compressor side. So far its been about a week-1000miles No smoke, No odd noises and still rips pretty damn good for a b5.5 on 18psi. I will turn up the boost once I find a decent intercooler replacement. Maybe sometime in the spring or after tax season I'll play around with compressor wheel/housing options and slap a 56mm+ compressor on this thing so I can flow more at a lower shaft speed keeping the setup more reliable. I believe the real manufacturer of this turbo is kinugawa or KTS who also supplies turbo options for just about any turbo OEM or aftermarket. I think sharing this information is good for the go faster community around the VAG scene. This manufacturer has been known/proven in the EVO/honda community for years now with great results from their products at an affordable price.
    Last edited: Jan 12, 2017
    RoachinRay likes this.
  13. RoachinRay

    RoachinRay Bags&Wheels BRUH

    I like stuff that works well and affordable!
  14. budsdubbin

    budsdubbin Posting- God

    Lately I've been trying to track down issues with excess crankcase pressure in the top end(oil cap dance) but after I've replaced everything in the pcv system and I am nowhere. So I'll have too keep checking into it.

    I also believe I found a company that produces a billet compressor wheel for the ko3-029 with the matching housing for about 200$. Comes prebalanced so its ready to spin out of the box. I currently have 38/51mm this will take it to 39.3/59.2mm. This compressor is about 4mm overall smaller than the one used on the ko4 frankenturbos for the b5s4. Probably going to order that up when I get my intercooler in.

    I'm running out of time before spring hits so I may start getting back to my 20th.
  15. corolon

    corolon Member

    You still here? How's it going, have you made any more mods to your car? I'd love an update, as it's been some time since you last posted :D
  16. budsdubbin

    budsdubbin Posting- God

    Hey yeah sorry I've been busy with job training in NYC and just life in general. I recently had problems with the passat throwing cel's for cam timing codes and found that my timing belt tensioner went loose on me. Thank god I picked up on that before it did serious damage. Replaced the fan clutch because its old and blew apart causing an annoying chirpping sound. I'm going to wait on the upgraded front mount intercooler after I do some more supporting mods on the faster car. Also found a good intercooler to throw on from M&M 6$ can't beat it. Current one is caked in oil but I've been running low boost to keep my ebay hybrid turbo together until I have that sorted out. Then I'll post some logs of how its performing. Even at 15 psi this setup is much more peppy then stock.
  17. corolon

    corolon Member

    Of course, no problem! I don't want to rush you or anything, of course life is more important than updating a thread.
    I really wish you the best, @budsdubbin, and good luck with your job training & your car!
  18. budsdubbin

    budsdubbin Posting- God

    So my new intercooler is installed and retuned/worked the PID to bring the boost up to 22psi. Butt dyno results leave me very happy. It rips for a little hybrid ko4. I'll have to do some more logging to determine where I am at but I have a feeling the stock injectors may not be enough for this turbo so I am looking into cheap alternative options. Next time the sun comes out you'll be reading more progress.
    BlackGTI likes this.

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