What do you think? Turbo on a Non Turbo

[Scott James]

Hi,
So this might sound a bit crazy, but i'll put it out there, I've done a lot of research recently on how to make my 2.5L z4 faster. and there isn't much option other than buying a different Z.
A mechanic friend of mine suggested the Idea of adding a turbo.
To me It looks like there would be room in the engine bay, However the real life problems Stack up massively.

Things like how likely will this just blow up the engine.
Will it require a completely new ECU or can the original be remapped.
Will it require Bigger injectors and will bigger injectors work.
How am I going to oil the turbo.
How am i going to get custom made Pipes / connectors
That's just off the top of my head.
But If it did work and the gains in Power were Great, Could it be a risk worth taking

Currently I only have a small amount of Engine / Car knowledge, but Just wanted to get some thoughts from you guys
Thanks

 

[Sean d]

Hi,
So this might sound a bit crazy, but i'll put it out there, I've done a lot of research recently on how to make my 2.5L z4 faster. and there isn't much option other than buying a different Z.
A mechanic friend of mine suggested the Idea of adding a turbo.
To me It looks like there would be room in the engine bay, However the real life problems Stack up massively.

Things like how likely will this just blow up the engine.
Will it require a completely new ECU or can the original be remapped.
Will it require Bigger injectors and will bigger injectors work.
How am I going to oil the turbo.
How am i going to get custom made Pipes / connectors
That's just off the top of my head.
But If it did work and the gains in Power were Great, Could it be a risk worth taking

Currently I only have a small amount of Engine / Car knowledge, but Just wanted to get some thoughts from you guys
Thanks

I think @machine monkey has done it

 

[Twin Turbo]

I thought a supercharger was the best option for this engine?

http://esstuning.com/ess-n52-vt1-supercharger-system-gen-2/

 

[Scott James]

I thought a supercharger was the best option for this engine?

http://esstuning.com/ess-n52-vt1-supercharger-system-gen-2/

Thats a pretty cool site, they make it sound easy, I wasn't sure if you were messing with me then. I wonder how much the Shipping would be, shame its in America.
I better start saving haha.

 

[t-tony]

Mat, Machine Monkey has mounted his turbo right at the back of the car. It's been a pretty involved job even for an experienced guy like him.

Tony.

 

[Redline]

I would expect supercharger route is the easier route to go, but, it depends how much you’re willing to invest in time and money to squeeze more power out.

Power increase would be more linear from a supercharger. I guess (possibly either route but definitely the turbo route) you also have to consider cooling the additional air charge with an intercooler.
Then you have to consider remapping the ecu.
Don’t know what brakes you have on the 2.5 but you likely need larger discs all round.

Lots of work, lots of money and lots of experimenting with no guarantee of success.
Probably cheaper to buy a 3.0L si and keep both

 

[machine monkey]

Hi,
So this might sound a bit crazy, but i'll put it out there, I've done a lot of research recently on how to make my 2.5L z4 faster. and there isn't much option other than buying a different Z.
A mechanic friend of mine suggested the Idea of adding a turbo.
To me It looks like there would be room in the engine bay, However the real life problems Stack up massively.

Things like how likely will this just blow up the engine.
Will it require a completely new ECU or can the original be remapped.
Will it require Bigger injectors and will bigger injectors work.
How am I going to oil the turbo.
How am i going to get custom made Pipes / connectors
That's just off the top of my head.
But If it did work and the gains in Power were Great, Could it be a risk worth taking

Currently I only have a small amount of Engine / Car knowledge, but Just wanted to get some thoughts from you guys
Thanks

Hi Scott



Firstly if you can’t weld or have a very good friend who can. I wouldn’t do a turbo build unless you have a lot of cash put aside for it.



The engine can and will blow up. If it’s badly mapped or set up wrong. The m54 engine is a well-engineered and strong engine. It should be fine left completely as it is up to about 300bhp. After that its a ticking bomb without doing head work maybe pistons and things. I have a m54b30 and i am aiming for 400bhp and I am just going to see what happens.



Yes unfortunately it will need a new ECU the ms45 ECU in z4s and latter E46 cars has not had the development that the ms43 had. Ms43 equipped cars can just be mapped to cope with a turbo. But again this isn’t ideal and you would have no control over an external waste gate other than relining of spring pressure. Or using an internal wastage both options not great.

Yes you will need bigger injectors. Extra air more fuel needed. You could add another 1-2 injectors. But that’s not ideal. I brought a set of second hand cleaned and flow tested injectors from America they were less than £100 they are from a Volvo 2.0l turbo engine. Same injector bigger flow.

Pipes joints mountings oil lines all tricky you will have to ditch the CCV system so you can use the dipstick drain for the oil return. But oil feed you will have to drill and tap a fitting in an oil gallery in the engine block. Or there are some oil filler caps that you can take feeds from. You will need an oil cooler anyway so that might be the best route.



If you haven’t done much like this before. And you don’t have friend’s family who have and are willing to help. And or you don’t have lots of cash. Buy a supercharger kit. My turbo build has cost me about £5k and take 18 months and hundreds of hours work. It’s not easy and i have done something a bit weird. Also what would you do about under bonnet temperatures? The z4 is known for having steering related issues on the electric rack when it gets hot.


Have a read through my thread to get an idea of what’s involved.

Some good news you can buy a bolt on manifold, you can buy the oil filler caps to supplies oil and you can drain the turbo easily. I am also sending my car to a company called SCS Delta and they are using my car as a development car. So they will be selling an off the shelf plug and play fully programmable ECU that fully integrates into the car. And it’s very cheap for what it is. But still £1400 your budget for this should be about

 

[t-tony]

Cheers for that Mat.

Tony.

 

[Pingu]

Currently I only have a small amount of Engine / Car knowledge,

My advice would be to look at standard, higher performing cars with similar engines and copy them This was how I started modifying.

Get the parts and bolt them on. It will never be as simple as that and the fettling that you need to do will be the added value that puts the smile on your face.

After that, try copying and fabricating parts based on those performance parts.

Then you can advance to designing, fabricating and fitting parts that are totally your own design.

Running before you can walk will only make you want to throw your tools in the bin.

Top Tip...the best £10 I have spent recently was on a book "Four-Stroke Performance Tuning" by A Graham Bell. (ebay)

 

[machine monkey]

I agree with Pingu



If you want to do it do it. Just don’t expect it to be easy. And whatever you do enjoy the process of doing it. And ask questions. I have and i have had lots of help. And I didn’t know all the answers before starting my build. You will have to research and learn things. But that’s half the fun.



Scott where in the UK are you?

 

[Scott James]

Thanks all of you for your advice. Really helpful.

I would be more than happy with 300bhp, so good to know the engine should with stand it as that was one thing I was worried about. Destroying the car completely.

@Pingu I really like your way of starting with smaller engine mods, any suggestions on where might be a good place to start? And ill check out that book so thanks.

@machine monkey thanks, gave me alot to look into and Think about before going ahead with it, but feeling more confident knowing it can be done. Im in south west wales, but i used to live in Oxfordshire (Near Didcot)

It would be a great journey with hopefully the end product being great.

 

[Pingu]

... any suggestions on where might be a good place to start?

Think - MASS AIR FLOW RATE.

The density of the air flowing into the engine can be increased by cooling the air.

Volumetric flow rate can be increased by removing obstacles to flow, both going into and coming out of the engine.


Ultimately, it is the car that you want to go fast, not the engine.

Always make sure that your brakes are not binding, your tracking is true and your tyres are at the correct pressure. It's easy to test by feeling how your car slows in neutral. You can measure the drag using a dashcam and calling out the speed as you slow, or by using a datalogger, such as TestO. Here's my slowdown graph...

You can also think about weight. If you can remove 70kg from a 1400kg car, that will have the same effect as adding 10bhp to a 200bhp car.

 

[John Thompson]

Hi,
So this might sound a bit crazy, but i'll put it out there, I've done a lot of research recently on how to make my 2.5L z4 faster. and there isn't much option other than buying a different Z.
A mechanic friend of mine suggested the Idea of adding a turbo.
To me It looks like there would be room in the engine bay, However the real life problems Stack up massively.

Things like how likely will this just blow up the engine.
Will it require a completely new ECU or can the original be remapped.
Will it require Bigger injectors and will bigger injectors work.
How am I going to oil the turbo.
How am i going to get custom made Pipes / connectors
That's just off the top of my head.
But If it did work and the gains in Power were Great, Could it be a risk worth taking

Currently I only have a small amount of Engine / Car knowledge, but Just wanted to get some thoughts from you guys
Thanks

Sell it and buy an E89 35i with the twin clutch auto box with paddle shifters, the twin turbo puts out over 300 in standard formy and easily uprated to 380 - 400 bp reliably. They are a blast to drive, there is no turbo lag, none at all, and the gearshifts are milliseconds. If you plan on keeping it a long time it must be the best route to go, I wouldn't buy a car from someone who did a did supercharger or turbo, IMHO, lots to think about ma man

 

[Grumps]

Hi Scott



Firstly if you can’t weld or have a very good friend who can. I wouldn’t do a turbo build unless you have a lot of cash put aside for it.



The engine can and will blow up. If it’s badly mapped or set up wrong. The m54 engine is a well-engineered and strong engine. It should be fine left completely as it is up to about 300bhp. After that its a ticking bomb without doing head work maybe pistons and things. I have a m54b30 and i am aiming for 400bhp and I am just going to see what happens.



Yes unfortunately it will need a new ECU the ms45 ECU in z4s and latter E46 cars has not had the development that the ms43 had. Ms43 equipped cars can just be mapped to cope with a turbo. But again this isn’t ideal and you would have no control over an external waste gate other than relining of spring pressure. Or using an internal wastage both options not great.

Yes you will need bigger injectors. Extra air more fuel needed. You could add another 1-2 injectors. But that’s not ideal. I brought a set of second hand cleaned and flow tested injectors from America they were less than £100 they are from a Volvo 2.0l turbo engine. Same injector bigger flow.

Pipes joints mountings oil lines all tricky you will have to ditch the CCV system so you can use the dipstick drain for the oil return. But oil feed you will have to drill and tap a fitting in an oil gallery in the engine block. Or there are some oil filler caps that you can take feeds from. You will need an oil cooler anyway so that might be the best route.



If you haven’t done much like this before. And you don’t have friend’s family who have and are willing to help. And or you don’t have lots of cash. Buy a supercharger kit. My turbo build has cost me about £5k and take 18 months and hundreds of hours work. It’s not easy and i have done something a bit weird. Also what would you do about under bonnet temperatures? The z4 is known for having steering related issues on the electric rack when it gets hot.


Have a read through my thread to get an idea of what’s involved.

Some good news you can buy a bolt on manifold, you can buy the oil filler caps to supplies oil and you can drain the turbo easily. I am also sending my car to a company called SCS Delta and they are using my car as a development car. So they will be selling an off the shelf plug and play fully programmable ECU that fully integrates into the car. And it’s very cheap for what it is. But still £1400 your budget for this should be about

Excellent reply.

 

[Redline]

Think we’re heading in to the discussion on torque and power very soon.
Just throwing power in to a car won’t necessarily make it any quicker in the circumstances that you normally use the car.
Modern turbo cars have multiple turbo technology that helps deliver greater torque lower down the rev range. You don’t get the punch in the back at 3k+ revs that you used to.
It’s the reason that superchargers are suggested. They deliver an increased air charge at all revs but more effectively at lower revs. That’s going to give you much greater acceleration. Torque is what accelerates you to a high speed quickly. Power is what keeps you there.

 

[t-tony]

Then there's Electric cars. They can do it all? But, no sound.

Tony.

 

[hard top]

But, no sound.

Some use sound generators ....

 

[machine monkey]

Think we’re heading in to the discussion on torque and power very soon.
Just throwing power in to a car won’t necessarily make it any quicker in the circumstances that you normally use the car.
Modern turbo cars have multiple turbo technology that helps deliver greater torque lower down the rev range. You don’t get the punch in the back at 3k+ revs that you used to.
It’s the reason that superchargers are suggested. They deliver an increased air charge at all revs but more effectively at lower revs. That’s going to give you much greater acceleration. Torque is what accelerates you to a high speed quickly. Power is what keeps you there.

You are right modern turbo systems are better now. But also turbo technologies have moved on so much too. Superchargers are great but they also consume power and all the time. I built a turbo car that will come to life after 3k rpm and to make it fast and fun to drive the gears will need to be used. And if I don’t want to do that i can toddle around and get decent mpg too.

 

[machine monkey]

Thanks all of you for your advice. Really helpful.

I would be more than happy with 300bhp, so good to know the engine should with stand it as that was one thing I was worried about. Destroying the car completely.

@Pingu I really like your way of starting with smaller engine mods, any suggestions on where might be a good place to start? And ill check out that book so thanks.

@machine monkey thanks, gave me alot to look into and Think about before going ahead with it, but feeling more confident knowing it can be done. Im in south west wales, but i used to live in Oxfordshire (Near Didcot)

It would be a great journey with hopefully the end product being great.

I know Didcot just down the road from me. I also have family in south Wales. If you can buy a plug in ECU with a base map it is just cutting welding and fitting. Once you have sized things and planed the system. Don’t guess on what turbo to get speak to professionals. Compressor racing are very good and sell good quality turbos. You don’t need a garret in fact I don’t like them. I have a Holest hx35 it’s a great turbo and capable of 500bhp.

 

[Redline]

You are right modern turbo systems are better now. But also turbo technologies have moved on so much too. Superchargers are great but they also consume power and all the time. I built a turbo car that will come to life after 3k rpm and to make it fast and fun to drive the gears will need to be used. And if I don’t want to do that i can toddle around and get decent mpg too.

Agree about the power consumed by superchargers. Guess I’m now too used to lots of low end torque driving a 3L 6 pot petrol and a 3L 6 pot twin turbo diesel.
Many years ago I used to have a Fiat uno turbo. That was a hoot but the push in your back only started at 3k revs. If you want that power and are prepared to work the car to get it then it’s a great solution.