Z4 3.0i vs 3.0Si

[junglie]

I have had a 2003 Z4 3.0i in the past and thought it was fantastic.

Potentially looking to get another Z4 as a weekend / special use car and there are some nice 3.0Si examples creeping into budget.

My question is this - is the 3.0Si worth the additional over the 3.0i? It has the 256bhp mill and a few external cosmetic changes(?) but is the driving experience massively different?

[anonymous-user]

The SI is slightly better on fuel and slightly quicker. But not so much as you'd notice in real world driving. The old 3.0i is a solid lump but I believe the Si can suffer from a few engine issues.

[junglie]

I had heard that also which may result in the venerable old 3.0i being the better choice.

[soprano]

I've had a 3.0i Z4 and driven a 3 series convertible with the same (I believe!) engine as the Si. 3.0i was good but in my view the Si engine was a better drive

[abarber]

Quite a difference if driven back to back. The Mag block 3.0Si engine is a bit special. Loves revs and is very light.

All on the same dyno: http://www.dyno-plot.co.uk/dyno/dynoplot/id%3D786_...

[edition]

SI engine is the same as the 130i, amazing engine imho.

[pilchardthecat]

M.....

[ratty6464]

The 3.0si engine is great. Direct injection enables decent economy on a cruise, peak torque is around 2750rpm and the car effortsly glides around town on low revs. Then when you really open it up in 3rd and 4th gear it really hammers along between 5000 - 7000 rpm.

The 3.0i in contrast, whilst still a very good engine, is less keen to rev - especially higher up the range - and less economical with it.

The 3.0 is good but the Si is great.

[junglie]

Sounds like the 3.0SI may be a good bet after all - I like that peak torque comes in sub 3000 rpm which must make it more tractable.

Have seen one on the trader for £9,500 which may be a good example.

[junglie]

Apart from the SHOUTY ADVERT what do the collective think of this?

http://www.pistonheads.com/sales/2978061.htm

[Fox-]

Have driven cars with both engines, not a huge amount of difference. The torque figures are largely the same therefore the extra power comes from the fact the Si revs a bit higher.

[R_T]

junglie said:

Apart from the SHOUTY ADVERT what do the collective think of this?

http://www.pistonheads.com/sales/2978061.htm

Interesting options! 'ONBOARC COMP' 'STEERING CONTROLSLED LIGHTS'

Ignoring the shouty style and spelling, I was unaware that Z4's had steering control lights as an option (as in directional?).