Pushing a 2.5Se passed 200bhp

[Dr. Zed]

You say your car is an '04 plate in which case it is almost certain that your VANOS system will be completely defunct or only partially working. Spend your money on a VANOS rebuild kit and do it yourself or pay a specialist to rebuild it for you. You will find levels of torque that are at the moment completely missing from your engine. I rebuilt the VANOS on my 2.5i last year and wish I had done so years ago ! Definitely well worth doing

This is actually on the top of my list to do. I'm just waiting for my mate to finish doing some DIY on his house (and restrictions to ease) so we can use his drive. I can only do a certain amount of work on my Zed here as it's parked in residential parking of an apartment complex. But it's definitely at the top of my list to do because my car has done 102k and I doubt it was ever changed.

 

[Dr. Zed]

A very good point indeed. Did exactly this on wifey's 2.5i. Then reset the adaptations. After about 100 miles it was noticeably smoother. After 500 miles the fuel consumption had improved by about 3mpg, which I guess would come down to the recovered torque (it's an auto, so that may affect it too)

In short OP, it seems that whilst you asked how to get 200bhp from your motor, you have instead been given many ways you can make the car run, feel and perform better. Decisions, decisions.... :wink:

Well I think I'm scarping the idea of just playing with the numbers of 200+ BHP and instead focus on the VANOS and then maybe a remap.
But it's nice to get some decent input for it all anyways

 

[Dr. Zed]

There's rumoured to be a legend the townspeople talk about on here sometimes. Whether it's legend, myth or the ravings of madmen and women we'll probably never know.

The legend goes that there was once a brave but foolhardy individual who had a Z4 roadster but wanted more speed. The car was hardly used and cleaned to within 1 micron of paint depth any time it was taken out for a drive.

The legend continues to say that our hero proclaimed from the rooftops that the Z4 would have a turbo fitted and that Z4M drivers would be quaking in their driving footwear at the thought of this lowly 2.0 or 2.2 Z4 beating them at the traffic light grand Prix. How the townspeople laughed, pointed at him.

Carved in stone tablets, the legend says that the car was in a garage somewhere in the sprawling mountains of Norfolk. The car was guarded by a fire breathing dragon, crocodiles and piranha infested swamps.

The fierce beasts were very attached to the Z4 and wouldn't let our hero get the car back even though it was now probably useless and the engine probably in bits. However, he did eventually get the car back.

After all that it's said that on dark, wet and windy nights you can still hear the Z4 turbo spooling and the noise from a fake dump valve along with the maniacal laughter of the ghost driver who pilots the haunted Z4 across B Roads.

Opinions vary on whether it was actually completed or it was all fantasy but somewhere there may or may not be a Z4 with a burgundy roof that was once almost, nearly, could have been fitted with a turbo.

Well, safe to say if anyone needs me I'll be over here.. on the edge of my seat.
On a serious note though, I'm a new Z owner and relatively new to the forum so I imagine this turbo charged Z4 is a bit of a icon around here (possibly even built/owned by yourself?)

 

[Dr. Zed]

Not much you can do to increase midrange torque in an naturally aspirated engine... most conventional power mods are about removing air and fuel restrictions, and making power close to the redline. Possibly at the detriment of midrange torque.

To get more midrange, you either need bigger displacement (ie switch to a 3 litre) or add boost.

Also, to get the most out of any NA engine, it needs to be revved!

I'd like to think I'd one day get a 3.0 Z4 but until then I'm definitely not planning on playing with trying to turbo the thing!

 

[skelters]

There's rumoured to be a legend the townspeople talk about on here sometimes. Whether it's legend, myth or the ravings of madmen and women we'll probably never know.

The legend goes that there was once a brave but foolhardy individual who had a Z4 roadster but wanted more speed. The car was hardly used and cleaned to within 1 micron of paint depth any time it was taken out for a drive.

The legend continues to say that our hero proclaimed from the rooftops that the Z4 would have a turbo fitted and that Z4M drivers would be quaking in their driving footwear at the thought of this lowly 2.0 or 2.2 Z4 beating them at the traffic light grand Prix. How the townspeople laughed, pointed at him.

Carved in stone tablets, the legend says that the car was in a garage somewhere in the sprawling mountains of Norfolk. The car was guarded by a fire breathing dragon, crocodiles and piranha infested swamps.

The fierce beasts were very attached to the Z4 and wouldn't let our hero get the car back even though it was now probably useless and the engine probably in bits. However, he did eventually get the car back.

After all that it's said that on dark, wet and windy nights you can still hear the Z4 turbo spooling and the noise from a fake dump valve along with the maniacal laughter of the ghost driver who pilots the haunted Z4 across B Roads.

Opinions vary on whether it was actually completed or it was all fantasy but somewhere there may or may not be a Z4 with a burgundy roof that was once almost, nearly, could have been fitted with a turbo.

It was an ongoing saga for a long time. We don't talk about it any more!

Well, safe to say if anyone needs me I'll be over here.. on the edge of my seat.
On a serious note though, I'm a new Z owner and relatively new to the forum so I imagine this turbo charged Z4 is a bit of a icon around here (possibly even built/owned by yourself?)

 

[Smartbear]

the sprawling mountains of Norfolk.

Every single word was completely believable except these five!

What do I know. I'm just passing on the legend to the younger townsfolk.

Jonny Essex never got a turbocharged z4, it stayed normally aspirated :?
Rob

 

[skelters]

Every single word was completely believable except these five!

What do I know. I'm just passing on the legend to the younger townsfolk.

Jonny Essex never got a turbocharged z4, it stayed normally aspirated :?
Rob

So the leg-end says as is written in the historic stones of Z4 yore. Although it is legend so who knows what really happened unless they were actually there.


It was hilarious at the time though.

 

[Dr. Zed]

It was an ongoing saga for a long time. We don't talk about it any more!

Sounds intriguing for sure. I'll keep my lips sealed so!

 

[skelters]

It was an ongoing saga for a long time. We don't talk about it any more!

Sounds intriguing for sure. I'll keep my lips sealed so!

The first rule of Fight Club is....

 

[Dr. Zed]

The first rule of Fight Club is....

Shhh..

 

[Jakg]

Tuning an NA engine is going to be expensive, especially when ignoring the easy option of dropping the 3.0 in.

I'd be looking at cams, but it's going to be very expensive.
At least with the 3.0 there is the ZHP cam option.

 

[Argyll Andy]

Tuning an NA engine is going to be expensive, especially when ignoring the easy option of dropping the 3.0 in.

I'd be looking at cams, but it's going to be very expensive.
At least with the 3.0 there is the ZHP cam option.

Or just buy something like this that I saw popped up on eBay :lol:

https://www.ebay.co.uk/itm/224435275367?hash=item3441628667:g:iJUAAOSwkUZgcGmz

 

[Ewazix]

It's like mine, 192 bhp stock. A good service, mapping to take advantage of premium fuel, turn the air-con off and run it on a cold day and you might see over stock on a very well kept older engine. But why not do a Colin Chapman and chase power-to-weight instead? much easier and more productive with the advantage of improved handling. Someone on here had a weight shedding thread.

 

[enuff_zed]

Look, you only need 8 more horse power.
Try this:
(May need a bit more cleaning on the front end!)

 

[Dr. Zed]

Look, you only need 8 more horse power.
Try this:
(May need a bit more cleaning on the front end!)

Right I need to go see a man about a horse...

 

[Dr. Zed]

It's like mine, 192 bhp stock. A good service, mapping to take advantage of premium fuel, turn the air-con off and run it on a cold day and you might see over stock on a very well kept older engine. But why not do a Colin Chapman and chase power-to-weight instead? much easier and more productive with the advantage of improved handling. Someone on here had a weight shedding thread.

Did cross my mind but shedding weight usually means getting rid of other things like passenger seat, radio, etc. Things I generally want to keep

 

[Ewazix]

It's like mine, 192 bhp stock. A good service, mapping to take advantage of premium fuel, turn the air-con off and run it on a cold day and you might see over stock on a very well kept older engine. But why not do a Colin Chapman and chase power-to-weight instead? much easier and more productive with the advantage of improved handling. Someone on here had a weight shedding thread.

Did cross my mind but shedding weight usually means getting rid of other things like passenger seat, radio, etc. Things I generally want to keep

In which case just enjoy driving it and spend the money on proper maintenance

I'm in my 12th year with mine and it still makes me smile and surprises with linear performance when you give it the beans, they just keep giving and so smooth. 99% of my Z4 driving is fair weather, hood down A + B roads so a 5 speed with about 200bhp is more adequate for most situations.

 

[Dr. Zed]

Mine was definitely not very well looked after by the previous owner. The owner before that I don't know..
Mine is my daily but I've always found people are too scared with higher mileage and stuff like that.
Just take care of a car and it'll last. Since I've taken ownership of this car I've fixed the issues and maintained it properly and it's running smoother better now than when I bought (got it for a decent price to be fair).

 

[Ewazix]

Mine was definitely not very well looked after by the previous owner. The owner before that I don't know..
Mine is my daily but I've always found people are too scared with higher mileage and stuff like that.
Just take care of a car and it'll last. Since I've taken ownership of this car I've fixed the issues and maintained it properly and it's running smoother better now than when I bought (got it for a decent price to be fair).

Sounds good