Let the tinkering begin...

[Greg Roles]

Like Jamyz's recent post, I too have always been one to tinker with my toys.

ECU mods and similar major warranty risking options will be last on my list, if at all. I watched Ford during my time in my last FPV, go from "overlooking" modificatons, to voiding entire warranties for cat back exhausts. Ford also recently sold their warranty work to a third party insurer, and the rules changed again to even tighter.

Seems VW is currently "overlooking" the chip and tuning angle, and even my dealer principle brought it up on my test drive, but I'm wary that if enough start breaking and costing cashola, then the rules may similarily change.

Now don't get me wrong, it's not all doom and gloom, I just want to point out WHY I am doing things the way I am, and why I am bothering making minor mods that would yield bugger all HP, compared to a major, and easy mod such as a chip.

My aims are this:

1. Optimise what is already there.
2. Find the weak links.
3. Modify from there.

So I'm really keen for input from anyone out there who has played with their oiler, and can save me making too many mistakes.

1. Intake.

Straight up, the plastic VW use is beautiful to cut and file etc. A real treat.

The inlet is well designed, and has nice internal trumpets on all the inlets. Only small casting rings are evident, and thought has gone into the overall flow design. The pickup draws from the frontal high pressure area, and has an excellent splash protection design, with air flowing through the scoop and hitting the sealed airbox, with the inlet drawing from above this "flow". The bend around to the box is smooth, but does pass close to both the radiator hose, and the exhaust gas recycle tube, both probably adding heat. The filter box is well designed on the inlet side with a nice 45 degree to middle inlet style, maximising the filter area. There is a big screen in the bottom of the box, which seems unecessary given the grill on the front of the pickup. The outlet makes me wonder, being right up one end, with a lid that has reinforcing vanes across it. This then passes close to the silver injection pump? which gets pretty hot. A fairly blunt and square edged MAF? sensor comes next, before the crankcase vent joins the party just prior to the turbo.


I took off the front rubber strip on the bonnet, and used it to make a seal just around the intake. The rest I left open to allow a bit more airflow to the engine. The plastic lip covering the radiator seals against the bonnet underlay, so I removed a section of this in front of the turbo area. This is metal reinforced, so it was a bit of work to do nicely. The rear bonnet seal remains in place to force any airflow down, over the hot turbo.




I placed a plate in the back of the splash designed inlet scoop, and only left a small, matchstick wide gap along the bottom for any water ingested. Despite the crazy weather lately in QLD, chances of major splashing are slim, so I'd rather the ram air effect. I removed the guard that partly seperates the inlet tube from the lower box, and sanded the internal trumpet smooth. Heat shielding on this curved pipe is next on the list.





The filterbox was sanded in the bottom, and I'll run a K&N, just because I like to service it a lot. I doubt there is anymore than a fraction of a HP available here. I removed the vanes in the lid, and again sanded the trumpet smooth.




The plastic grid that sits in the bottom of the box was sadly lost during this procedure, thus left out.

The MAF sensor had very square edges, so I shaped this assembly as aerodynamically as possible, even if that just meant removing just the hard edge. This looks a bit restrictive. This section of the inlet will also be heat shielded from the silver doobie beside it. It looks like the injection pump to me.
Bottom line it gets hot, and nothing kills a turbo's performance more than heat.

[Greg Roles]

2. Crankcase venting.

My god!

At 800kms, my inlet was SOAKED with oil, and there was actually a pool in the elbow just prior to the turbo. Undoubtably my intercooler is already nicely oiled, and this is fine, but once the exhaust gas recycling joins the party just prior to the black plastic inlet, well I reckon soot plus oil equals sludge.

I first played around with a simple foam / scourer pad filter in the short CCV vent tube, but the sheer amount of pressure ( I would guess due to the high diesel combustion pressures ) was too great for this, and it wanted to pop off all the time. A LOT of oil venting takes place, so serious venting needs be considered.

I ended up installing the Mann & Hummell Provent 200 as outlined on TDIclub.com.
http://forums.tdiclub.com/showthread...ht=provent+200

The good news is there is a Man & Hummel distributor in Sydney. The bad news is they are friggen expensive at $200 PLUS post. Ow!

I'd have to say that it is indeed a well designed and engineered item, and thus far has been working a treat in the TDI. The inlet is still spotless, and the filter is only just starting to get soaked with oil. Finding suitable hose was the biggest issue, I purchased reinforced Dunlop rubber hose to fit the 3/4 inch Provent fittings initally, but this was simply too huge. I ended up with the smaller rubber hose I bought for the lower oil trap. I made an alloy bracket between the battery platform and the firewall, and put the rather big filter below the inlet tube in the only real space there is. Only hose specific shops have any sort of suitable hoses, I tried several places first, auto shops, bunnings etc.

Running hoses was a major biarch, and mine is still only temporarily plumbed in ( ie sikaflex involved ) until I can locate either better hose, or a nicer way to plumb it.




The bottom line is that it is definately filtering out ALL the oil vented, and given the size and design, should be good for the life of the engine.

[Greg Roles]

3. Cooling.

The biggest power robber to turbo's is heat, so this is my next area to attack. The TDI runs a nicely sized silver intercooler between the AC radiator at the front, and the standard engine radiator at the rear. Being silver, the first thing I plan to do next week is to remove it and paint it black, for this is always worth a couple of degrees of inlet temp. Sealing the radiator around the edges to the frame is on the cards as well, for air will always take the path of least resistance.

The oil has a little cooler below the oil filter housing, but as this is behind the above three radiators I wonder as to it's real effectiveness. I've e-bayed a nice little B&M oil cooler, and this will be plumbed in parallel with the existing cooler and put out the front of the radiators somewhere. I am aware each heat source in front of the intercooler is a drawback.

I will run an intercooler misting system, for I reckon this is a great idea especially up here in ( usually ) sunny QLD.

The intercooler pipes seem well plumbed, but I've yet to really look into how close they come to heat sources. I now have a lot of sticky heat tape to wrap the inlet in, so I'll be going to town there.

I've a turbo beanie coming for the exhaust side of the turbo, and a stack of 3" wide, thick ( good grief ) header wrap for the first part of the exhaust. Yeah I've heard the stories of this causing corrosion and weakening welds, but if it does indeed break that's great, for I can get a better pipe made up to replace it.

It's all in the aim of reducing underbonnet temps, thus reducing inlet temps. I had planned to take a lot of before and after temp and pressure measurements, but was simply too keen to get in there and start modding, so I've no proof of anything. I've boost, EGT and oil temp and pressure gauges coming, so I can get some readings as I go.

I'd also like to say that this is all from my unqualified head, and anything anyone chooses to do with his or her car as a result is up to them!

[Greg Roles]

The spoils of war... thus far

[Jaymz]

All looks good and very interesting Greg. I spent alot of time doing simple yet very effective mods like this to a car i once owned and I have no doubt you're on the right track.
So the biggest question is, when are we getting together so we can do this to mine! Lol

Cheers,
Jamie

[Greg Roles]

When I work out what works, and what doesn't, I'm sure we can work something out for the Brisbane crew. Screw everyone else

[les88]

Cogdoc,
on Top Gear tonight they had a comment about chipping the motor reduces turbo life quite a lot.
Also I read your thread on Ford with chipping, I didn't touch my XR6T too scared of being black balled by Ford. The drag races attracted Ford spies with cameras taking your Vin. Why do you want to boost the little 2.0 lt motor when your Ford would eat all the VW's the for breakfast.
les

[Greg Roles]

Hey Les,

I agree JUST raising boost, without also raising cooling, lubrication, filtering, heatsinks and other stress lowering factors is usually bad news for longevity. Raising boost raises thermal load considerably, and things need to be modified to counter this. Manufacturers factor in the load with the boost they run, but remember things like the oil cooler are built to a price, rather than optimum efficiency. I've no doubt a decent oil cooler alone will drop the load on both the oil and turbo tremendously.

WHY do you think I'm doing all this up front? In case I end up risking the warranty and raising the boost! In the meantime, I get a bit more juice with the stock ECU, and a lot less stressed and longer lasting turbo oiler!

I tinker because Tim Allen is my idol, and it's what I do. There's ALWYAS more to be had! arrr arrr arrrgh.

The old BA GT would win in a straight line for sure, but only until the next corner!

[gldgti]

nice work mate. i like your philosophy.

cheers
aydan

ps - good to see a fellow dieseler who's not afraid to get under the bonnet and pull **** out.

[GoLfMan]

i like this work mate, your not just pulling random stuff out but you are thinking about the process first, good to see someone that isnt afraid to attack a new car alot braver than me mate