Cleaned the side mount intercooler, got some ideas...

[Buller_Scott]

Don't want to be a stickler, but it's a 1749vC baby. VB is in the 103 TDI. Fair bit different actually.

oops! gotta do my homework.on tdiclub lots of the guys are happy with the VB, i had always presumed it was from the pd150- but look what presumptions get you! but then again, there are a few different turbos that, on tdiclub, have different ''street names'' to their actual names. e.g. the garrett gt 1749v label covering stock sized turbos, and also being used as a nickname for the borg warner BV39 and the KKK KP39.

they SHOULD be direct bolt ons, from what i know, preeny.... people are using the same bolt on upgrades, be they mk3 golfs, 9n3 polos, skoda fabias, etc etc.

frigging rain. rain rain rain. i wanted to get under the car and have a look around, take some pics. but of course its gotta rain. hopefully this arvo.....

[Greg Roles]

Yanks only get the 103kw TDI in their jetta's, thus all they know is the VB. Once they finally get the 125kw engine, they'll be playing with the VC. My only question in retrofitting the VB/VC would be how to run the VNT mechanism, as this is one of the key differences between the two, with the VC having a more complex control mechanism to allow much finer control. The VC has a different inlet housing, not sure on the impeller. I believe the exhaust is quite similar, but it's hard to find out much at all, I've sure spent many hours searching!

A bigger turbo is going to give you crappier down low by the way....I for one am not interested in making an even narrower powerband!!

[Buller_Scott]

hmmmm.... well, that's true. i was hoping that the fact that the gtd [aka gt tdi] turbo would still have little lag as it's a VNT, but you make a pretty damn good argument.

on the cards is deffo a straight through intake, maf grid removal, larger pipework.

but then i've gotta address front swaybar, coilies, all the bushes, and hopefully eventually clutch and maybe even lsd for go-round-corners-better radness. although people might laugh @ an lsd on a car as underpowered as a polo tdi... who knows...

had the thought of bigger turbo crossed your mind seriously, cog? or rather, optimisation of all on-board systems, with a little extra [e.g. dpf delete + water meth]?

[Greg Roles]

Nope. A bigger turbo that flows more air will inherently have greater lag. It's why manufacturers have twin turbos, to avoid the drivability issues for high power factory turbo cars. The turbo in the GT already flows a lot of hp for a diesel stock, and it has that big turbo rush as it comes on song, any bigger would just aggrevate that point, unless you got lucky and matched up something better than VW did. And you can bet they trialled a LOT of turbo's, something a normal person can't do. I'd look to the UK to see what the polo TDI guys are doing over there, as there may indeed be a bigger VNT turbo off another VW such as the GT that does still give a "full" powerband, but in my case, no, I can't see any reason to go bigger when close to 200 hp and crazy torks seems very available on the stock turbo.

Having said that, turbo and injectors are the usual limiting factors in any diesel, so long as flow in and exhaust out are optimal.

So yes, i'm going option two mate!

[GoLfMan]

Im also looking into a Turbo upgrade. But I'm undecided as to which one. I'm thinking the GT turbo would be the best option, as I have a goal of 120kwatw+.

I was thinking a GT2260VK but this would give me almost nothing below 2500, which would just be pointless in city traffic.

Scotty, where are you finding these turbo's? Im coming up to the 100k mark and Im just hoping like hell my turbo doesn't give up the ghost anytime soon!

[Greg Roles]

Mate I find VB and VC's on e-bay overseas quite a bit! VNT1749 search.

[GoLfMan]

Mate I find VB and VC's on e-bay overseas quite a bit! VNT1749 search.

sweet

next question is if the manifold from the GT bolts up to our PD100's

[Greg Roles]

Doubt it, more likely the 1749 could be adapted onto the polo one already there. You could always go nuts and get a custom manifold, which is on the serious end of things.

[Buller_Scott]

Scotty, where are you finding these turbo's? Im coming up to the 100k mark and Im just hoping like hell my turbo doesn't give up the ghost anytime soon!

hey man, mostly reading on tdi club, but of course those guys get the american spec motors, so i dont know what will work really, to be honest.

i would LOVE to simply bolt on a pd130 turbo like the on on motorcade.co.za, but we have all read about the reliability issues of the pd130 [1749va, i think].

another option is a gt1756, people on the club reckon that's low-lag but a nice boost on stock. another option still, seems to be to tweak the components of the stock turbo- i think i read that you can add larger wheels etc to stock turbo, and pretty much retain all other stock usability like manifold, pipework, etc?

here's a link for a vb:
garrett GT Turbolader GT1749VB ARL

not bad pricing, and a VERY feasible option instead of stock replacement.

but as for your turbo, josh, i think it should be fine- lots of people on tdi club reckon that their vnt15's are good for 100,000 MILES. and what with proper warming up and cooling down etc, no hard driving upon cold starts, etc, yours should be doing fine. it'd be the stock vnt's of peeps who use their cars as an A-B hack vehicle, no warm up, no cool down, that i'd be worried about.

cheers!

[Preen59]

I know of a high number of Caddys that have done over 300k+ with no turbo failures. I wouldn't be too concerned with turbocharger failure.

Water+meth injection will lower your EGT's too, if you want some more bang without having to fiddle.


What's the dealio with the MAF grid removal? Does it net any improvement?

[Buller_Scott]

i think it was cog, and transporter, who reckon that straight-through intake [removal of all the bends in the air box] +++ maf grid removal = it's as though the car has had the air con on the whole time, and now you're turning it off.

if that's the case, i certainly want that for mine... just gotta sort out a smaller battery etc first.

p.s. water meth is siiiiiiiiick. im looking at that sometime down the track....

[gldgti]

sweet

next question is if the manifold from the GT bolts up to our PD100's

arent the PD engines counterflow? If so theres no way the manifolds will bolt up surely? VW kept the same counterflow port spacing setup through all the vw diesle from the 1.5 n/a right upt to the mkIV golf PD150, but i dont know about after that.

[Greg Roles]

MAF grid and a straight through pod made it a little more responsive in all honesty, don't expect big things there. It all helps, but the grid is there because of the 90 degree airbox lid exit, so until you remove that, leave the grid in place. Modshack reckons it's a 22% restriction. In the GT inlet, from what I've found, I reckon the biggest restriction is the EGR flap mechanism. It's a very poor flow design in my TDI at least, but not an easy removal. I'm still working on that!

[Buller_Scott]

hey cog, i was looking at my egr/ inlet again last night, and specifically at the egr flap...

now, i dont want to revolutionise tdi modification at all, im a pretty humble kind of guy, but i think im really onto something...

you know how the flap sorta looks like a large coin, with a horizontal pin through the middle of it, upon which it flips open and shut?

now i was thinking, what if you dremelled the flap above and below where the pivoting pin thing is, so that you just have the pin, still able to spin open/ shut, but with no more flap attached to block off post-intercooler air flow?

or would that set sensors off?








p.s. i was mostly joking, but also a little inquisitive

[gldgti]

if you remove hte flap itself, the egr wont work properly.... that would probably throw a code or two.