Tuning bits. Vectra C 1.9 CDTi SRi 150

Harvey

Tuner
Points
157
Location
Darlington
Car
Vectra CDTi 280/437
Can anyone help me with the following for the GM/Fiat/Alpha/Saab 1.9 turbo diesel:
1. Larger diameter MAF sensor as I have maxed out the OE 60 internal diameter MAF sensor body. Bosch 4 pin plug.
2. Bosch MAP sensor, again 4 pin, 3 bar or more required to allow me to run 1.9 bar. I guess the existing is 2.5 bar as it maxes out at 255kpa.
3. Alternative turbo. I already have a 56 wheel in place of the OE 49 diameter compressor wheel but think I am getting close to max.
4. Does anyone know the power capability of the turbo on the LT35 VW?
5. Someone capable of live mapping as opposed to importing a CDM or EDS/IPF map file. I am hoping to live map on the road or on the rollers and followed by a final road session to take account of the existing mods.

Power measured on Scooby Clinic's DynoDynamics was 158 bhp and 234 ft.lbs when I started this some months ago. Last week 230 bhp and 335 ft.lbs.

I have very little small diesel tuning knowledge so any input appreciated.
 
MAP sensor from a VAG 1.9TDI 130/150 is rated to over 3bar I think it may fit with a bit of fiddling it will fit to a PSA Hdi so I would have thought the Fait Multijets would have been able to use it as well.

MAF sensor, i'm not so sure but again you could try the VAG 1.9TDI 130/150

As for the turbo then I'm not so sure, a BMW 330d uses a GT22 of sorts,

What kind of power and torque are you looking to achieve?
 
Much has happened since October. It appears the current map sensor will allow the car to run at the target 1.9 bar. A 3 bar map sensor is 3 bar absolute and allows 2 bar operation so the map sensor issue may not be the problem I previously thought.
I am informed that maxing out the MAF sensor at 172 g/s is not a particular issue as long as the tube diameter is big enough to allow more air flow even if it is off the scale. Whereas on a petrol it would be an issue that apparently is not the issue on a diesel.
The current turbo is a Garrett 17/49 with the compressor housing machined by a local machine shop to take a 56 diameter wheel which I think originated from a VW hybrid. 17/49/56. The cost of the turbo was £77 delivered and the total cost of the wheel and machining combined was £70. So the cost of getting to 238 bhp at present (348 ft.lbs) has been very little.
When I have maxed out this turbo I will then try a BMW 330 56 compressor housing machined to take a 60mm wheel so the designation of this turbo will be 17/56-60.
If that is a stage too far then I can go back to 17/56 ie. the original 1.9 CDTi exhaust manifold and housing with a BMW 56 diameter compressor and wheel.
I will put pictures up of the new turbo that was put together for me by a friend who happens to own Turbo Solutions here in Darlington.
The car is booked in for mapping wc 22 January.
 
e87eio.jpg


jkgcqp.jpg


2w6xoxv.jpg


OOPS.
Didn't mean to post these but here is the inlet manifold showing the 8 ports four of which have flaps which are inclined to jam. Now that I have a spare inlet manifold because I replaced the original I am removing the flaps, plugging the spindle holes and doing minor porting work on the inlet manifold.
Prior to replacing the inlet manifold because of jammed flaps I superglued the flaps wide open (with the exception of no.3 which is controlled by a motor) and I could feel no particular change in performance, spool or response so I see no problem deleting the flaps in total.
A common fault on these engines, 1.9 CDTi, is that the flaps jam because of a build up of carbon and breather oil and the control rod then detaches from the individual flap posts.
 
Last edited:
21oawy.jpg

2wmjh9u.jpg

2hcdg6s.jpg

1zn3omt.jpg

1fzrmc.jpg

2cxuq11.jpg


Here is the 17/56/60 which will be fitted after I max out the 17/49/56, hopefully during mapping w/c 22 January.
 
Last edited:
Nice stuff there,

I guess you are limited by turbo choice somewhat as it is built into the exhaust manifold with the exception of using an SS header but they cost loads and at the moment i guess you wouldn't want to spend that kind of money.

Also did you manage to completely disable the EGR in the end or are you still using the plate with the small hole in it?

could you just make it recirculate back into the exhaust?
 
Because the manifold and exhaust section of the turbo are one piece and because of the space constraints between the engine and fans / water radiator I am not keen to try to make a new manifold which could be a great improvement before I determine exactly what turbo I would want to use.
The OE 17 exhaust housing may be too small for the 56/60 combination but it certainly works very well with the 49/56 combination.
This is my wife's car and I don't want to take it beyond what is reasonable and what may greatly shorten its life. The cost involved so far has been negligable in comparrison to the bhp / torque gain. Making a manifold and finding a suitable turbo for the space available and mounting on the middle of the manifold, not the end gets in to serious modifying and expense.
I have a plate blanking the EGR but this put on a CEL and so that plate has an 8.5mm hole in it with no CEL.
However, since blanking the EGR port which was very easy to do and running with the 8.5mm hole I have also removed the throttle body/ throttle flap. Without the flap there can be no vacuum on overrun so the exhaust gas recycling doesn't have any vacuum to operate it.
Coupled with that I have also redirected the oil breather to an oil catch can (old Royal Purple Plastic oil bottle) so there is no more oil mist going in to the inlet manifold anyhow.
I suspect that either blanking the EGR or removing the throttle body or a combination of both has slightly increased fuel consumption so I am going to selectively look at replacing the TB which will be knife edged and see what difference that makes and then do the same with the blanking plate.
 
I know you considered Water/meths as well, and that should keep the intake clean so if that's a worry then that would be the way to go.

DevilsOwn do good price kits

Also have the injectors been up to the job or have you maxed them out?
 
The oil breather mod ensures there is no oil mist present.
The lack of throttlebody and hence no vacum ensures there is very little EGR, if any.
Further, the blanking plate, even with a hole in it ensures that even if there were any EGR it is very substantially reduced.
On top of all that I am removing the tumbler flaps as I could determine no improvement with or without. At that point the common fault of sticking flaps and detaching link bar is of no consequence on this engine.
I am not sure of the cleaning effect from a methanol water mix but depending on the sequence of the next mods I guess I will find out. Adding water methanol to cure EGR issues is however, rather extreme and expensive.
I need to find time to install the water methanol kit I already have. I plan to use a small jet at medium boost to improve fuel consumption or atleast find out if that actually happens with a bigger jet at higher boost to add performance. I am not sure when I will get this done but it is interesting.
 
Update as at 19 May 2012.
In February 2011 the car attended a rolling road day at RS Tuning, Leeds, where it produced 216 bhp and 375 ft.lbs. The car has water methanol injecting just before the inlet manifold. This is a 2 stage system from Snow Performance in the US. Stage 1 is at medium boost to improve fuel economy and stage 2 is at higher boost to develop power.
I have experimented with various turbos and the above figure was using a 17/49/56. I also tried a 17/52/52 and a 17/52/56 both of which were disasters. The 17/56/60 produced a shed load of power, 280 odd bhp but the torque was moved up the rev range by about 500 rpm and as the car is my wife's daily driver this was removed. I then ran 17/56/56 which was capable of an easy 240 plus bhp. I then redeveloped an alternative 17/56/56 and at a rolling road day in February this year produced 268 bhp 437 ft.lbs.
Significant mods in addition to the turbos tried and the water methanol injection above are ported inlet manifold, modifield air box and induction, ported exhaust manifold, total decat exhaust system hand made with see through silencers but the car is not too loud, front mount intercooler. I made this up myself using a Hybrid/HDi tube and fin core intended for a Subaru STi. (I am the Hybrid European distributor, Technical Adviser and Pro Installer).
I monitor air charge temperature and exhaust gas temperature.
Mapping by RS Tuning in Leeds.
Earlier this week I fitted the final incarnation of this combined turbo incorporating exhaust manifold and was pleasantly surprised that we were spooling to 1 bar in 4th 150 rpm earlier but I could not get 4th gear accelleration figures from 1500 rpm to 4000 and 5000 rpm which I had obtained from the previous turbo simply because the turbo was grossly overboosting. Obviously the latest incarnation of turbo is moving even more air and the car will be mapped again by RS Tuning but they cannot take it until 7 June.
All in all this has been very interesting as it is the first small diesel I have tuned.
Having aquired numerous bits throughout the project I now have all sorts for sale including a fully overhauled pair of turbos with ported exhaust manifolds, 17/49/56 and 17/56/56.
 
Last edited:
437lbft!!!! Awesome.....

Mate youve achieved the highest figures on these engines Ive ever seen...In the VX comunity they are convinsed that its near impossible to get more than 220hp~ from these....

I might need to pick your brains again in the future for some advise again...
Glad youre back on here after all this time, Ive already seen you on subaru forums before...
 
437lbft!!!! Awesome.....

Mate youve achieved the highest figures on these engines Ive ever seen...In the VX comunity they are convinsed that its near impossible to get more than 220hp~ from these....

I might need to pick your brains again in the future for some advise again...
Glad youre back on here after all this time, Ive already seen you on subaru forums before...

I think there is a bit more to come. I will know mid June. The turbo fitted last Wednesday spools even quicker but I have no idea as to ultimate power until it is mapped so there is a delay.
My experience and within the mods I have done and relying only on RS Tuning rollers to keep everything comparative is that the OE turbo, 17/49, probably struggles to get much past 200 bhp. With my mods getting 250 bhp plus on a 17/56/56 was not a particular issue and with modified injectors this actually ran 268/437 lbs.ft and the next incarntion of the turbo, despite earlier spool, will be good for more.
Unfortunately different rolling roads read different figures and not all rolling roads are consistant but the RS Tuning rollers appear consistant and others have said they generally read lower than most others.
I am quite happy to share my knowledge with you when the time comes and I will PM my contact details including phone numbers.

Yes I am heavily involved in Subaru tuning and have been over a period of 12 or 13 years and many things that are accepted now are my own innovations or as a result of my own development work. When I joined the Subaru community I was told 400 bhp would be immpossible, if it was done the car would be undriveable as a daily driver and it would only last a short time. It was not long before I produced 417 bhp at a rolling road day and now outputs of 400-500 bhp are common place, I have 3 Subaru Wagons on the road with 450, 500 and 600 bhp and those that are involved in competitions such as Time Attack are achieving 700 and 800 bhp but the bigger power output engines are 6 cylinder not 2 or 2.5 litre 4 cylinders.
I also happen to be the Hybrid European Distributor, Technical Adviser and Pro Installer and it was a Hybrid core I used on the Vectra to improve the intercooling as power increased. I also do a lot of porting work, tubular headers, my own design "trick" uppipes which are acclaimed across the world and a limited range of turbos or turbo repairs. I am also heavily involved in mapping and some ECU development work.
Effectively what I have done with the car above, which is Dawn's daily driver, is to apply my engineering knowledge but as I quickly found out, tuning a diesel is a lot different to extracting power from a turbo petrol.
 
Last edited:
So far all I have done with the 1.9 CDTi manifold and exhaust housing is port it and I think I have gone as far as I possibly can using the original 17/49 turbo as a base. I have just fitted another incarnation of the same turbo which will be mapping soon and the results, good or bad, will be very revealing and help me determine the best way to go. The replacement turbo waiting to be mapped is spooling 150 RPM earlier, much against my expectations but it is grossly overboosting and I need to resolve that issue, hopefully with mapping so I do not lose the earlier spool.
Then I guess it is time to look at alternative manifold systems to allow the selection of different turbos but it is a balancing act to select a turbo that has good spool yet gives good power.
 
For me that is too much work and complication for not very great gains. The space available is a major consideration and why run 2 turbos when one will do?
The reason for running 2 small turbos is no lag and immediate spool but we are only dealing with a four cylinder engine so I don't think that is an option. The alternative is to run the turbos on series just like the BMW 535D but that is a six cylinder 3 litre with a lot more space for packaging.
On an engine of this size I don't think there is a case for dual turbos unless it was designed by the manufacturer from the start. Saab had a twin turbo arrangement and I don't think that was particularly successful or well received.
Personally I would like to stick with what is tried and tested and get the best from what is there.
 
With latest turbo after mapping.
In February this year at a rolling road day the car did 268 bhp/437 lbs.ft.
On the first visit to RS Tuning February 2011 the car did 216 bhp.
All mapping over the last 14 months at RS Tuning, Leeds.

208jtaf.jpg

4zt21e.jpg

dpkb5x.jpg

2n7qcus.jpg
 
Saab had a twin turbo arrangement and I don't think that was particularly successful or well received.

Oh contraire! this system used on their TTiD diesel engines was indeed well received for both maintaining good fuel economy and better than petrol style performance. :)
 
This car must be bombastic to say the least,

Anyway, i wasnt on about twin turbo, compound turbo/supercharging is different all together, and different to squencial systems,

its a small and large charger working together in there efficient ranges to make more boost than a single can manage and also a bigger spread of torque,
its a big turbo blowing into smaller turbo or a supercharger (usually a roots type)

Its the way youll have to go if you want more power and retain the lowdown torque
 
Thanks for that T9. Your views are different to those of the local Saab dealers or at least a couple of their mechanics. My only experience on a Saab Twin Turbo was that there was a bit of a step in pull when the second turbo came in higher up the rev range. This has also been my experience on modified twin turbo Subarus but it matters not as it is not something I will be trying.
Jarrus: I see the advantage of running a Supercharger to increase power below say 1700 rpm but I don't think there is any advantage achievable on this engine after that point or much after that point anyway. (from a Supercharger). I have full boost by just over 2000 RPM. I think the engine internals are stretched to the limit at 280 BHP so I am not in a hurry to exceed that figure and I accept the limitation of only making 1 bar of boost at 1700 RPM so while the spread of torque could be improved a little, low down, with a blower, I suspect it is more hassle than it is worth and not something I want to spend my time on. However, I am very interested in other people's suggestions and thoughts. It would be nice if someone else wanted to experiment in that direction but the limited experience I have with Superchargers is that they generally run at no more than 10-12 PSI. Let me know what pressure other cars with Superchargers run as that would be good information.
I also looked around for steel rods and forged pistons but as far as I could tell the only option for the 1.9 CDTi engine was custom made and that was prohibitively expensive. Again if somebody knows different I am all ears but without upgrading engine internals I think it would be unwise to go much further.
 
You probably would have to go custom made on the rod mate, pistons arent needed and cant really be done, diesel have an extra ring called the fire ring which is cast into the piston itself and no one has managed to do it with a forged piston,

If you were to go above 2 bar or boost the compound turbocharging is logically the only way to go, using your hybrid as a secondary and getting something like a Garret GT28 as a primary...

Also injectors might become an issue, who makes the 1.9 cdti injectors?
 
I have already been offered custom rods and pistons but the cost is prohibitively expensive. I also note that the latest development pistons for BMW, Mercedes and others are actually steel items not weighing any more than the aluminium counterparts because they are thinner.

If you were to go above 2 bar or boost the compound turbocharging is logically the only way to go, using your hybrid as a secondary and getting something like a Garret GT28 as a primary...


This is not what I think but I have no first hand experience of it. The existing turbo is quite capable of 2.3 bar and is still efficient and if I wanted it to run 2.5 bar or beyond it could do that but probably generating a lot of heat outside its efficiency zone. This would improve torque further up the rev range. It still makes 1 bar at 1700 RPM so the area of improvement would be below that RPM because the existing turbo is capable of more if I thought the internals were capable of handling that.

I have already increased the flow rate of the injectors by 19% and these are the OE Bosch as fitted to the Vectra by Vauxhall.
 
Interesting that Cummins are doing this too. I suspect a lot of diesel manufacturers will go down this route in the future but obviously they need experience in the field for such a radical change.
Why do you think the O/E pistons are OK beyond 280 bhp and greater boost than I am running? Running higher booost with this turbo or the last is quite possible and if I wanted a turbo to operate 2.3 or 2.5 bar that would not be an issue in building it from scratch but my current concerns are the integrity of the engine, particularly pistons and rods. When this engine is stripped I will examine it carefully with particular attention to rings, ringlands, piston crowns, rods and cylinder head to see if I can gleen any information.
Interesting times.
 
They are only for the after market at present and theres a few guys using them in there drag engines,

Your rods will definately give way first in the rotating assembly and like I said there currently isnt an really an option of upgrading your pistons,

You can get them coated like you can do on petrols, the crown can be coated and so can the piston skirt and that maybe worth a look but beyond that then forged aluminium are stronger but they just won last the course, and this is an everyday car, like I said before diesels have an extra ring cast into the piston which prevents this, not a problem on steel pistons as the material is stronger....
 
Thanks for the information. In every day trim the car is running the 279 bhp/437lbs ft map with water methanol. I did nothing with the injectors until around the 250 bhp bracket but remember I also had water methanol injection assisting power development. (10-18 bhp subject to how it was mapped). I looked into renozzling and what others had done with injectors on VAG, BMW etc. I had calculated I needed 15% more flow but there was no obvious nozzle replacement available to me and either nobody knew for certain or was not saying. I was then pointed in the direction of Keith at United Diesel and he agreed to modify the existing injectors. He clearly knew his lemons from his limes. A very clever guy and he confirmed that renozzling was not necessarily a good option as spray pattern is critical. The flow rate was actually increased 19% which was ideal for my intentions. I know that Vectra 1.9 120s have different nozzles to the 150s so I think changing nozzles is not necessarily a good thing if it can be avoided. United Diesels 01939 291155.
Until now I have built my own turbos starting with machining the 49 cover on the 17/49 standard VNT turbo to take a 56 wheel. I experimented with a variety of other turbo configurations based on the 17/49 and with the help of my friend Tim Waterson, Turbo Solutions, Darlington, we put together a 17/56 with the cover machined to take a 60 BMW wheel. This did 280 bhp 10 months ago but spool was 2300 in 4th gear on a level road and for a diesel in everyday use driven by my Wife this was just too high up the rev range and I went back to the 17/56/56 which we took to 275 bhp but 268 bhp in daily trim. The current turbo was built by Adam Davidson of TDi Turbos after we collaborated and shared notes on our previous experiences so anyone wanting a hybrid turbo would do well to get in touch with Adam at TDiTurbos@gmail.com
I am surprised how quickly we have moved on the 1.9 CDTi tuning platform in only a short space of time. A lot of hard work but others can now benefit from my efforts.
 
Cheers mate. If there is anything you want to know about specifically I can share my experience with you but some times I don't get on here for a few days.
 
Always a good read chap,
Apparantly the spray pattern of the injector is matched with the shape of the piston bowl so the fuel gets mixed as best as possible with the air,

Ive spoken to Keith, at United Diesel in Shropshire, he does know his stuff, he probably just enlarged the holes in the nozzles (well i say 'just' im sure theres more to it than that but that the basic jist)

I will have to talk to your hybrid turbo guy in the future i think...
 
I know I'm fascinated by just what can be done with an everyday diesel engine. I don't mean everyday in a bad way, just that its an engine like mine that's used in hundreds of thousands of cars.
 
Yes. There are some big power diesles about. The VAG guys have been at it for some time so the modification route is fairly well marked out and off the shelf parts are relatively easy to obtain. The 1.9 Fiat engine as fitted to Vectras, Astras,Saabs, Cromas, Alpha Romeos is not as well developed and tuning on these has not advanced very much until now.
I have just fitted my previous turbo and a Hybrid FMIC to a pre-facelift Vectra which already had a full decat exhaust. Mapped at RSTuning the owner phoned to tell me it did 240bhp and 350 lbs/ft which is an exceptionally good result considering his lack of mods, no water methanol and it was on a very warm day (30C in the RR cell.
So tuning these engines ha come on tremendously in the last 18mths.
 

Similar threads


Please watch this on my YouTube channel & Subscribe.


Back
Top