Max Stock turbo PSI

[m4282]

Hi all- does any one know the max stock turbo boost PSI which is allowed on a standard m4 vs ZCP M4 vs the potential M4CS?

[MNoob]

seriously dude?

[m4282]

Originally Posted by MNoob

seriously dude?

Yes seriously I was wondering what level of tune or programming did BMW do to increase the turbo boost to get the additional 19hp on the ZCP and another 10 from that to M4CS. I know the max boost on stock from what I read is around 18psi .... so I was interested in learning this threshold which BMW considers "safe" on the s55

[CloudVIII]

Originally Posted by m4282

Yes seriously I was wondering what level of tune or programming did BMW do to increase the turbo boost to get the additional 19hp on the ZCP and another 10 from that to M4CS. I know the max boost on stock from what I read is around 18psi .... so I was interested in learning this threshold which BMW considers "safe" on the s55

Approx. Average WOT PSI values Range

Stock=18-19
ZCP=19-20
Speculate CS=21-22 same as JB4 Map 1
JB4 Map 7=24-25 depending on fuelling

Stock turbos can run close up to 30 PSI. How sustainable is that? TBD

[m4282]

Originally Posted by CloudVIII

Approx. Average WOT PSI values Range

Stock=18-19
ZCP=19-20
Speculate CS=21-22 same as JB4 Map 1
JB4 Map 7=24-25 depending on fuelling

Stock turbos can run close up to 30 PSI. How sustainable is that? TBD

That's a good guesstimate on the CS what it shows though to me is that some of the newer tunes like BM3 are then reaping even more power with potentially the same boost that the CS will run and which BMW would consider safe for long term reliability.....

[Sleeper]

Originally Posted by m4282

That's a good guesstimate on the CS what it shows though to me is that some of the newer tunes like BM3 are then reaping even more power with potentially the same boost that the CS will run and which BMW would consider safe for long term reliability.....

Boost pressure is one small piece of the large tuning pie.

[m4282]

Originally Posted by Sleeper

Boost pressure is one small piece of the large tuning pie.

Agreed - but on FI engines it often is one of the key indicators of eventual wear and tear on vacuum seals which is very relevant to long term longevity.