Tt E60 M5

[edo]

I understand this totally.
however the cost is probably at least 1/2 of a normal conversion - but without comparison, we can all just say "yeah that sux, and wont be as good". would that money be better spent, on say 30" chromies

pop the bonnet with a rear mount, and its like "what turbo officer"

Its an M5...you have already dropped piles of $ & if you are considering turboing it & therefore making it worth 3/8th of fuck all then money doesnt come into it.

To do it properly would cost more, so? If it was done properly there is no reason why it wouldnt be legal.

I kind of get it on a cheap arse shitbox that just bolts up a kit in an afternoon...but I just dont see the point of doing a pox job on a very flash car.

Oh, would it melt your ice cream in the boot? That would suck, because it wouldnt get on boost between the supermarket & home...so it would take ages.

[CussCuss]

simple thought, is it actuallly possible to put 2 low mounts in the space of an M5 engine bay?

[edo]

You can do anything with enough money...and if you are turboing a M5 you have enough money so yes.

[walkie]

How fast does exhaust gas flow, etc....

I think this, and how fast the intake tract can be brought up to pressure are very important. If the exhaust gas produced from extra throttle gets to the turbos quickly enough that it's indiscernible, and if positive boost can be built in all that piping quickly enough that it's indiscernible, there obviously would be no noticeable lag.

I'm sure though that if you timed it, even if you couldn't tell by the seat of your pants, it would have to take longer to do both these things, and in turn, there would be lag. Whether it can produce boost at 1000rpm or whatever is not in question, there would be more of wait between throttle and boost compared to a standard system, and therefore more turbo lag.

[edo]

Nizpro did a bit of a test with inlet tract lengths.

Standard BA XR6t made 170rwkw

With the new inlet manifold & the inlet shortened by 3 metres (yes, 3) and the bigger i/c it made 225rwkw & it came on boost 300rpm earlier. Still running standard boost.

Given that standard boost is 7psi or similar & I suspect that you would want to run more than that the difference will only be more pronounced.

[GTSBoy]

I think this, and how fast the intake tract can be brought up to pressure are very important. If the exhaust gas produced from extra throttle gets to the turbos quickly enough that it's indiscernible, and if positive boost can be built in all that piping quickly enough that it's indiscernible, there obviously would be no noticeable lag.

I'm sure though that if you timed it, even if you couldn't tell by the seat of your pants, it would have to take longer to do both these things, and in turn, there would be lag. Whether it can produce boost at 1000rpm or whatever is not in question, there would be more of wait between throttle and boost compared to a standard system, and therefore more turbo lag.

Lag is not just how long it takes to come up on boost the first time you floor it. The real problem comes when you want to adjust the throttle to control attitude when really into the tight stuff, and the pedal response is 0.25 seconds too doughy to be useful. That's when any lag at all is too much lag.

[barM3]

I know turbos are different, but in an NA car a longer inlet tract gives better torque, and shorter more power up high.

[The Pupat]

ItsI just dont see the point of doing a pox job on a very gay car.

Fixed, you haven't forgotten the conclusion we came to at the F1 yet have you?


Like others have said. Spooling up piss-arse tiny turbos on a large engine quickly and thinking that's awesome is rather pointless to my mind since if you did it properly you could run a bigger turbo with the same (or less) lag/boost threshold and therefore make more grunt.

[walkie]

Lag is not just how long it takes to come up on boost the first time you floor it. The real problem comes when you want to adjust the throttle to control attitude when really into the tight stuff, and the pedal response is 0.25 seconds too doughy to be useful. That's when any lag at all is too much lag.

That too. I think it's pretty clear that all other things being equal, the most compact package will be the most responsive.

[SirGoat]

Dont bends come into it also? when i was getting a FMIC everyone went on and on about bends and how 90* was like 1 meter of piping or something ...

I ended up getting rid of the car anyway so that solved that issue

[CussCuss]

Dont bends come into it also? when i was getting a FMIC everyone went on and on about bends and how 90* was like 1 meter of piping or something ...

I ended up getting rid of the car anyway so that solved that issue

see the problem i have is that i hear everyone saying that, yet '1 meter of piping' has no quantifiable measure unless you actually do the calculations.

Back in the starion days, our blue furry friend actually crunched the numbers because it was claimed that the reduction in lag from having about 30cm of intake piping (stock, no cooler) would be better than the pressure drop, lag etc of an intercooler.

It worked out to be about 0.3s to fill the piping.