306 HDi with VNT15 from 1.9 TDi 81 Kw

[Turbodiesel93]

Hi,first of all,sorry for my english,its not my mature language... I just wanted to ask,if its possible to make this turbo work on 2.0 HDi 66 Kw version? I dont care about manifold or exhaust fitment,this can be solved,but i dont know if it needs modifications to the vacuum actuator... And do i need to change head gasket? I am aiming for 130-150 HP,just for daily use.

[Poodle]

Anything is possible with enough work, the biggest challenge will be mapping it to work well. You will need to use a vacuum actuator, you nay have one already, depends which car you have.

[Turbodiesel93]

How about clutch? Will it hold the power? I changed my clutch a year ago,now i ve got 50 000 km on it,i also have some SW upgrade(it was there,when i bought the car) to aproximitly 120 HP... I have this car for 4 years a its still very relaiable,just some basic service.

[Midnightclub]

You will more than likely need a new clutch if you're still on the original unless it's been changed already, a new OEM may be okay but it will largely depend on how it's mapped

[welshpug]

main problem you have with this turbo is the fact that the exhaust housing is cast one piece into the manifold, or at least all the ones I have seen are.

nice fast responding turbo on the VW engine, but its all in the ecu control.

[Turbodiesel93]

I found a turbo that is separated from the manifold and is pointing exactly where i want... https://auto.bazos.cz/inzerat/70922519/P...i-81KW.php I dont know if this czech website is working for you...The owner says that turbo is in good condition,doesnt smoke and it doesnt have any shaft play and it even isnt that expensive. I am planning this upgrade on August,because as a student i dont earn much money and in summer there will be more work,by then i will have enough money for this upgrade,so maybe this turbo will be sold,but in Czech Republic there are always many turbos for sale on this website,so i dont think this will be the last turbo for sale.

PS: I didnt get answer on one question: Will i need to change head gasket and send the head for machining it to flat? I have 300 000 kms on the car and it doesnt have any problems.

[toseland]

Won't hurt to change the gasket but if it isn't broken why fix it

---

Also 150HP should be OK with a standard clutch, but see how it goes

[Poodle]

No need to change the headgasket, these engines don't typically have issues, not like the old XUDs. So long as you don't go mad with boost, which i'm guessing you won't if you're using a pretty small gta series turbo. There is a high chance you will need an uprated clutch, especially if you use that vnt to it's full potential for a nice early spool.

[toseland]

still mine only slipped in 5th, and under heavy acceleration poodle, i was on full torque by 2200RPM which was well into the slippy range..

even then it only slipped up to about 3200 and then stopped so there might be a chance

[Turbodiesel93]

In this video you can see,how its plumbed: https://www.youtube.com/watch?v=VMfPiIxUUvI (On 0:13 you can see that its connected from intake to the actuator). Will it work the same for me? Or do i need to change the actuator from vaccum to boost? I dont want the turbo to explode or to damage the engine,so i hope there isnt needed too much boost for 130-150 HP.

[Midnightclub]

I don't want to put you off upgrading the turbo by any means, but you can see 150hp on the standard turbo easily enough

[darrenjlobb]

I don't want to put you off upgrading the turbo by any means, but you can see 150hp on the standard turbo easily enough

You can make UK dynos that read horse shit say 150hp+, but the car is unlikely to be making near that

[Poodle]

still mine only slipped in 5th,  and under heavy acceleration poodle,  i was on full torque by  2200RPM which was well into the slippy range..

even then it only slipped up to about 3200 and then stopped so there might be a chance

The potential spool up of this will be in a different league to an rhf5 dude. Still, there's always a chance as you say, i'd just be very surprised if the standard clutch were to hold for long.

Turbodiesel93: If you are using intake pressure as a control then you need to be using a boost actuator rather than vacuum.

[Midnightclub]

Most s2 hdis will be around 130+ at the wheels regardless of fly figure, he only wants 130-150 at the fly. Stock turbo will do that

[darrenjlobb]

Most s2 hdis will be around 130+ at the wheels regardless of fly figure, he only wants 130-150 at the fly. Stock turbo will do that

Nope....The horseshit UK dynos will tell you they are, but, they arnt.

[Midnightclub]

Well as most people don't have a dyno in their garden, they have to rely on 'horse shit uk dynos' to gauge what sort of increase they have over stock other than a bum dyno. You should do some back to back testing, be easy to prove wouldn't it.

[welshpug]

you think he hasn't done that?

[Midnightclub]

Well, let's hear what the 'real' numbers are then. I'd love to know.

[Matt-Rallye]

Well, let's hear what the 'real' numbers are then. I'd love to know.

I'm with you here. I know darren has done extensive dyno research and back to back testing of HDi's in various stages of tune. 

Darren, If you have a solid comparison base of figures please do post.  very interested!

[darrenjlobb]

Its a well discussed area, with lots of questions, and lots of opinions. And to really explain it from my point of view, would take a long while, which I don't really have right now, but maybe when I do have some more time, I will pick out some example dyno graphs from the many HDI powered cars that I have tested here and show the general results.

The first thing I would say though, is that from my experience, a good 90%, if not more than that, of HDI's that I deal with, or come across, are broken.... Even if everything appears to be good, they make poor power, throw codes, cut out, or run like crap.  These early generation CR systems on these 8v HDI's now they all have miles on them cause a huge amount of issues, and its extremely rare that one makes near stock power, even often the case on cars that are apparently "mapped".

Classic issues include, but not limited to bad MAF sensors, bad FPR's, bad HP pumps, knackered injector / injectors, useless air filters fitted badly.... , poor maintenance leading to early valve train issues.. wiring faults in the loom, and the list goes on, Normally cars will start and drive, but give all kinds of issues, and make poor power once you get them loaded up and logging what is REALLY going on...

So normally first mission with any HDI, is just getting them "fixed" before even considering tuning them, people tend to assume getting a new ECU calibration will just fix all the issues and make the car great again, but in reality, it will just make the problems 10x worse. The injection system is fairly limited on these engines to start with, never mind when power output is increase, any knackered / worn components instantly become a serious problem.

From my experience,  a "good" or sorted out stock HDI, will make around 84-86hp (Estimated flywheel power measured on a chassis dyno) I have never seen a HDI make book power, ever. With a basic recalibration or "Stage 1 tune" they tend to make around 118-119hp, but as said above, unless the car is actually sorted / working correctly, they will often make alot less, if even stock power! 

"Stage 2" power is something that is even more debatable, as so much depends on what has actually been done to the engine, how well the engine has been maintained over the years and lots of other factors. But as a whole, if the car has a stock clutch, stock intake/filter, stock turbo, larger exhaust, FMIC of some form and a MBC fitted to the turbo actuator to allow a manifold pressure increase, they generally make 135-140hp. And again, most will fail to do this without work / new parts. Normally cutting out randomly due to rail pressure dropping to low below request, or loosing power as valves begin to float at the top end from high EMP. 

I know endless people have Dyno graphs to prove there car is making x power and x torque, and you can read into this what you want, I also know that if i put my DT on a random dyno, it would probably make 250hp+....So why don't I just go and take my car somewhere to generate such a graph? Because I'm not interested, I could fudge the figures on my own dyno if that was what I wanted to do, but I don't.... I understand how the dyno works, and how it is calibrated, and math doesn't lie. Its a highly debated subject, so can read into it how you like. It can be a bit of a "heart breaker" in alot of cases, but always makes the numbers I am expecting....Just maybe not the numbers the owner is always expecting. 

End of the day, the 8v HDI in the 306 is fitted with a 46mm turbo from 19+ years ago.... Do the math, sure your car is making 155-160hp? 

Im not having a rant, I, and others I know have learnt alot of the last few years, and the one thing I would say now, is that the internet can sometimes be full of rubbish, and if you want to know something, best thing you can do is go out and try for yourself!!

[Midnightclub]

Interesting stuff, certainly puts a bit more light on what the forum tuners on here claim their tunes will make.

[Turbodiesel93]

Wow, didnt expect this much attention... Anyway,i just wanted something different,that spools sooner and better.We will see how it will go,the clutch isnt that old,but if it would not be able to hold the power,then i dont have many choices,than change the clutch for better one,but dont know,if i can buy something like this in our country,i know that the TDi(TDi are sadly more popular in Czech republic) tuners are remachining(hope its the right word) the clutch disc to some organic HDS57.

Poodle: Thanks,thats what i want to know... But how is then the boost controled,so the turbo doesnt overboost and cause damage? By its veins? I´m really sorry for my english,i am trying my best. I was writing on our czech forum and they told me,that it will be hard to convert the actuator from vacuum to boost.

[Turbodiesel93]

I was searching more info about the clutch and i found a site,that makes organic clutch,that will hold more power and its cost is only about 800 czech crowns,which is about 25-30 pounds.Then some people on forums were saying,that they tested this clutch on many cars like Leon TDi with more than 300 HP and 500 NM and it was holding pretty good for long time.... So i think,that this will be my choice.

[tigerstyle]

I was searching more info about the clutch and i found a site,that makes organic clutch,that will hold more power and its cost is only about 800 czech crowns,which is about 25-30 pounds.Then some people on forums were saying,that they tested this clutch on many cars like Leon TDi with more than 300 HP and 500 NM and it was holding pretty good for long time.... So i think,that this will be my  choice.

That sounds very good! And very cheap too!

I would say that if you do all that work and your stock clutch doesn't slip.... don't celebrate, it just means you are making next to no power! 

I love Darrens reply, should come with a warning it is so savage!

[Piggy]

Darrensdyno...aka...The Heartbreaker.

Just to compare... At SaxonMotorsport I made 206bhp at the wheels. With many upgrades later... My bum dyno said it was waaaayyy better but I made a lot less on The Heartbreaker.

Was I upset...no... Well, not about the figures at Lobbland anyway. I know where I'll be going in future and its a land of walls and corn

[lolsteve]

I thought "stage 2" included clutch? What you listed as stage 2 sounded more like a 1+ which was accepted at being the 140ish range.
Cheap clutches don't last, are you sure they're not just painting it red for that money?

[darrenjlobb]

HP has nothing to do with clutch's really, Clutch's are effected by torque, the engine produces torque. You could put 400hp through a stock clutch if you made the power at the right RPM....

All these "full fat" stage 2 maps which "require" a paddle clutch produce is a huge surge in torque in the midrange, leading to a dead feeling motor in the top end. Although should point out I have tested / worked on plenty of DW10's with paddle clutch's in them. But to be honest by the time there finished most likely don't even need them, decent linear power output will drive much much nicer than a big hump of torque mid range, which is largely all people fit the paddle clutch's for in the first place....

[Turbodiesel93]

Its not whole clutch set,its only for clutch disc and because my actual clutch isnt that old(like i said before i´ve done 50 000 km on it),i will only change clutch bearing,because its rattling from between the engine and gearbox when the car is cold,but only when car is stationary,if i press clutch,rattling is gone... When i am driving,there are no bad sounds other than turbo siren sound Its strange that after the car is on operating temperature,the siren is gone(its not that loud after the rebuild a year ago,before the rebuild it was a lot worse,but anyway if i will be installing different turbo,i hope that i wont have this kind of issues) . Question is,will the other parts hold the power for long time(i mean like two or three years,more will be better)?Cylinders,valves etc.. and gearbox

[Turbodiesel93]

Just one more question... I wont be able to tune the car immediately after the upgrade,is it possible (and safe)to drive it like that for about a month? Also does someone know torque specs for inlet manifold and exhaust manifold?

[Poodle]

You will have the boost control all wrong, could be damaging and/or awful to drive.