tdi vs gti

Chat about your 9n Polo (inc GT and Fun)
Ruan9n
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Re: tdi vs gti

Post by Ruan9n »

K.I.T.T. wrote:Does it really matter? At the end of the day there's always going to be something faster / better out there. There's no point comparing apples to oranges. A remapped 9n3 GTi would kill a remapped PD100.

Ash
I have a vnt1749vb (cupra turbo), fmic, pd160, bmc filter, 63mm turboback exhaust.
I lined up at a racetrack with a friend of mine who has a polo GTI with pd160, 76mm exhaust, forge tip and revo. 1st race I beat him second race his bonnet just slipped over the line before me. A properly done pd100 wont take crap from the GTI's :mrgreen:

BTW. when I was still running software on those mods except the bigger tubo I pulled gaps on stock polo gti's.
K.I.T.T.
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Re: tdi vs gti

Post by K.I.T.T. »

Ruan9n wrote:
K.I.T.T. wrote:Does it really matter? At the end of the day there's always going to be something faster / better out there. There's no point comparing apples to oranges. A remapped 9n3 GTi would kill a remapped PD100.

Ash
I have a vnt1749vb (cupra turbo), fmic, pd160, bmc filter, 63mm turboback exhaust.
I lined up at a racetrack with a friend of mine who has a polo GTI with pd160, 76mm exhaust, forge tip and revo. 1st race I beat him second race his bonnet just slipped over the line before me. A properly done pd100 wont take crap from the GTI's :mrgreen:

BTW. when I was still running software on those mods except the bigger tubo I pulled gaps on stock polo gti's.
My original statement still holds true, ie a remapped PD100 (GT1749V) (circa 140 BHP) would be beaten by remapped GTI (circa 200 BHP). From a rolling start though, the TDI might have the advantage.

I've got no doubt that a PD100 with a 1749VB would be more than a match for a remapped GTI, but like I said apples and oranges. Start bolting on different turbos and you're opening another can of worms. You're basically now a PD150 minus the injectors.

PD100 done up properly should be able to do 240 BHP if not more reliably. Apart from the oil squirters and different conrods, the only things that differ between that and a PD130/150 are the turbo (1749VA/VB resp.) and injectors (550cc vs 465cc). Additionally the PD150 has a different crankshaft (not necessarily a good thing), lower CR (18:1 vs 19.5:1) and FMIC.

Ruan, you considered swapping injectors to PD150 ones? With the rest of your setup, you'd be on the verge 200 BHP...may need a new clutch though.

BTW, In case it looks like I'm being defensive of the GTI, I'm not :P My daily is a 1.4 TDI which had 75 BHP stock :lol: Plan on building it to do 150 - 160 BHP with PD130 injectors, 1749VB and 6 speed 'box. Should be ~100kg lighter than the 1.9 too so should be quite nippy :mrgreen:

Sorry for the hijack.
Ash
Ruan9n
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Re: tdi vs gti

Post by Ruan9n »

I'd like to get hold of a cupra or pd130 head and just bolt that on, it does come with the injectors!
Clutch is a problem yes, not sure what setup to go for though! PD100 has a 228mm dualmass flywheel clutch. Aparently one can fit a Golf3 VR6 clutch and an ABF flywheel. This would be a very strong clutch :twisted:

The problem i'm having at the moment is the MAP sensor. PD100 has a 2.5bar map and the pd130 has a 3bar MAP sensor. The altitude at which i'm sitting in South-Africa is a problem. Atmospheric pressure is close to 1bar so that leaves the MAP with 1.5bar to pick up......and i'm running 1.7bar on the 1749vb.....

Can I just fit the 3bar MAP and push the software a bit further?
K.I.T.T.
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Re: tdi vs gti

Post by K.I.T.T. »

Regarding the MAP sensor, if you just swap it out for a 3 bar one, the ECU will need to be recalibrated to work with it, else it'll go into limp mode. Any good tuner should be able to sort this out for you.

Any idea what max boost pressure the VB is good till? I know someone who was running 24 psi, which is just under 1.7 bar...I'm wondering if it can hold 1.8 bar in the long term without blowing up...I should be able to reach 160 BHP with 1.75ish bar...If not, might see if I can get a GTB1756VK.

(Actually, if you reach 160 BHP with 1.7 bar, I probably can as well...I'm not entirely sure how it works with me having one less cylinder, but as long as fuelling is accounted for, I think same fuel + same boost = similar BHP :?: )

And sorry Dan for stealing your thread :lol: Ruan, we should probably start a new TDI discussion thread :P

Ash

PS: Check out tdiclub.com, loads of info there. I'm on there, same username.

EDIT: Re boost pressures: Read this http://forums.tdiclub.com/showpost.php? ... stcount=16
Last edited by K.I.T.T. on Wed May 05, 2010 3:36 am, edited 1 time in total.
Dub_Dan
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Re: tdi vs gti

Post by Dub_Dan »

K.I.T.T this is what its all about dude! im intrigued to know about both of your cars! only thing i hate about the diesel is first and second ratios being so short! and you have my vote towards another tdi discussion!
:D
K.I.T.T.
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Re: tdi vs gti

Post by K.I.T.T. »

Dub_Dan wrote:K.I.T.T this is what its all about dude! im intrigued to know about both of your cars! only thing i hate about the diesel is first and second ratios being so short! and you have my vote towards another tdi discussion!
:D
Not much to know about my car...It's a 1422cc TDi with 75 BHP stock :lol:. Basically a PD100 minus one cylinder. It's been mapped and was dynoed in March and put out 104.5 BHP (I reckon it's got a few more ponies in there...we came to the conclusion the dyno operator was errr...incompetent).

It's by no means fast. Nippy? Ish. I'm aiming to build the UKs fastest 1.4 TDi once uni's out of the way and I've got some cash coming in. Everyone says don't bother, put a 1.9 in, but I just want to prove them wrong 8)

Regarding the 1.9, what do you want to know? I know Ruan said he wanted to put a PD130 head on his, but in reality, there are PD100s bordering on 300 BHP. You've just got to uprate a few parts, conrods being the most significant. The PD130/150 conrods are better than the PD100 ones, but I'm not sure by how much. I need to read up on this as the 3 cyl PD75 shares quite a few components with it.

Stock PD100 + stage 1 remap = ~140 BHP. Swap over to a PD130 (GT1749VA) or PD150 (GT1749VB) turbo and you're looking at ~160ish BHP. You've reached the limits of the injectors then.

PD130/150 (same part no.) injectors are good for 210 - 260 BHP depending on who's dyno you want to believe :lol: The general consensus is 220ish BHP is the max 'safe' limit for these injectors. In combination with PD130 / 150 turbo and a FMIC, the injectors will get you to ~175ish and 190ish BHP respectively. You an get over 200 BHP, but you need a (very, very) good tuner Stock SMIC only good for ~170 BHP.

After that, things get a bit more expensive. A GTB1756VK (from a 2.7 TDI) combined with these injectors should get 220 BHP, maybe a bit more. If you wanna get really serious (and have the budget), you need Bosio Race 783 nozzles to be swapped into your injectors and a GTB2260VK...should be good for 300 BHP, albeit without modifying the head (porting, etc) I'm not sure if you can get more than 270ish. The most I've seen was a mk4 Golf which came to the dyno day in March. Putting out 266 BHP with the 2260 and 783 nozzles.

The more you boost, the 'bigger' the MAP sensor you need, but that's not a big issue. < £25 for a 4 bar one which is the most you'll EVER need.

That's it in a nutshell. Also bear in mind the stock PD100 clutch won't hold much more than 350 NM of torque I think.

Best bang / buck I'd say is 1749VA/B, PD130 injectors and FMIC.

Ash
Ruan9n
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Re: tdi vs gti

Post by Ruan9n »

K.I.T.T. wrote:Regarding the MAP sensor, if you just swap it out for a 3 bar one, the ECU will need to be recalibrated to work with it, else it'll go into limp mode. Any good tuner should be able to sort this out for you.

Any idea what max boost pressure the VB is good till? I know someone who was running 24 psi, which is just under 1.7 bar...I'm wondering if it can hold 1.8 bar in the long term without blowing up...I should be able to reach 160 BHP with 1.75ish bar...If not, might see if I can get a GTB1756VK.
Would my remap basically have to be done all over if I fit the 3bar sensor?

Mates of mine that run pd130's with the stock vnt1749 run 1.9 and 2.1bar boost! One has 133kw 500nm and the other has 155kw 525nm and the have been driving without ANY issues for 50 000km.

I had a 2bar map on my vnt15 and the car made 118kw 434nm but the turbo blew after going 220km/h + :lol:
Now its steady on 120kw 400nm and the clutch holds fine :mrgreen:

Wanna uprate my boostpipes for my FMIC, the bends in the one I have now i'm not 100% happy with and wanna go with a mandrell bend setup :wink:

That damn MAP sensor is keeping me up at night :(
K.I.T.T.
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Re: tdi vs gti

Post by K.I.T.T. »

You might not necessarily need to get the map re-done, just really needs a single parameter altering.

I'm not surprised you blew a 1749V with 2 bar, I don't think they're good for much over 1.5 bar :lol: Reagarding your friends' cars, whilst there have been no issues as such, I reckon it's more down to luck. Unless they're running 1.9 bar at 3500 RPM, and the mapper has reduced it to 1.65ish bar at 4000 RPM. If you read the link I added at the end (2 posts back) you'll see what I mean.

Ash :)
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zedzo
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Re: tdi vs gti

Post by zedzo »

ash you know anything about engine mounts?
my engine started shaking the other day forward n backward im thinking its an engine mount not had a look tho been to busy. any ideas on what it can be?
doesnt have anything to do with the dual mass does it
doesnt make any noise what so ever just shakes forward n backward. :roll:
K.I.T.T.
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Re: tdi vs gti

Post by K.I.T.T. »

zedzo wrote:ash you know anything about engine mounts?
my engine started shaking the other day forward n backward im thinking its an engine mount not had a look tho been to busy. any ideas on what it can be?
doesnt have anything to do with the dual mass does it
doesnt make any noise what so ever just shakes forward n backward. :roll:
Not really keyed up on engine mounts (or suspension etc for that matter). I doubt it's the mounts though. Sounds like a bush...forgotton what it's called, but I think there's one at the bottom of the engine. Maybe that's knackered? Doubt it's the DMF. If anything, a DMF is meant to reduce vibrations. Deifnitely wouldnt cause the engine to 'move' I would've thought :?

Ash
g__humm
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Re: tdi vs gti

Post by g__humm »

Dog bone bush this is called
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zedzo
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Re: tdi vs gti

Post by zedzo »

thanks for that g, ill have it checked out 2mro.
looks like ill have to drive the 220bhp A4 for now :lol:
K.I.T.T.
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Re: tdi vs gti

Post by K.I.T.T. »

zedzo wrote:looks like ill have to drive the 220bhp A4 for now :lol:
Yeah, I bet you're gutted :lol:

Ash
Ruan9n
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Re: tdi vs gti

Post by Ruan9n »

K.I.T.T. wrote:You might not necessarily need to get the map re-done, just really needs a single parameter altering.

I'm not surprised you blew a 1749V with 2 bar, I don't think they're good for much over 1.5 bar :lol: Reagarding your friends' cars, whilst there have been no issues as such, I reckon it's more down to luck. Unless they're running 1.9 bar at 3500 RPM, and the mapper has reduced it to 1.65ish bar at 4000 RPM. If you read the link I added at the end (2 posts back) you'll see what I mean.

Ash :)
Blew a vnt15 the stock pd100 one, had a vnt1749vb fitted now, the cupra garrett one.
The guy that does our software is the best with TDI's in SA. He has some of the strongest cars around the world in my opinion. The boost level will taper off at higher rpm....
This was my 2bar map compared to my 1.7bar map on the blown vnt15. Don't have a current graph with the vnt17 though :x

Image
K.I.T.T.
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Re: tdi vs gti

Post by K.I.T.T. »

That's a good map. Love how the torque smoothly comes in rather than goes bang...should be easier on the clutch.

I actually did a few calculations on what different turbos could do on the 3 cylinder engine... (don't use these boost figures for 4 cyl, they need to be ~30% lower than those below)

GT1749V should boost to 1.65 bar reliably = ~150 BHP
GT1749VA, 1.8 bar = ~165 BHP
GT1749VB, 2.2 bar = ~200 BHP

PD150 injectors should flow a minimum of 165 on mine, maybe 180 if I'm lucky. Just don't know whether to go for the VA or VB. My aim is 165 BHP initially on stock internals to keep things safe. Any further than that and I'll be using PD150 pistons to reduce the CR and rosten conrods...don't see it happening though. I think 165 bhp for a daily should keep me entertained.

Ruan, how does the VB feel compared to the VNT15? Did you notice a slight increase in lag? I know the VA spools up a bit quicker than the VB, but the latter can boost higher. Thing is, I want it to spool as quickly as possible, esp on the 3 cyl, which will take slightly longer to spool it up...

The stock turbo on mine isn't even VNT....GT1544s...wastegated and really small :(

Ash
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