even better heres the actual Email from supersprint italy fro YEARS ago, who imo hold far more weight than anyone including myself in terms of constructions and materials used etc .... These people are massive and spend big money researching OEM to their own, the fact they use HJS materials in search of a better cat says it all. They are amongst one of the best exhaust manufacturers out their imo, particularly for bmw, AMG.
hi Byron
Yes, the Z4M stock cats are 400 cpsi, Not the 200cpsi you are quoting, we have done extensive testing with them.
In comparison to the mainstream, oem ceramic cats, which are 500 cpsi to 600 cpsi, or even more on some cars, they are a huge step forward; but in terms of sheer resistence against free-flowing, they are nowhere near to what the 100 cpsi race cats do offer.
The car manufactures always have to deal with very stringent emnission regulations, and also with lowering the production costs as much as possible, at the same time.
This is the main reason behind the poor design of most of the stock exhausts, excpecially since the late 90s.
In the case of Z4M, BMW did a half hearted attempt, in searching the best performance, by specifiyng a nicely designed, lightweight headers, but choking down its flow potential, by adopting a set of 400 cpsi cats.
It's difficult to speculate how much more hp and torque you will make with the SS cats, on your S/C Z4. But we believe that it will be quite noticeable, no less than that.
We only have dyno charts available for our in-house, back-to-back tests, done on the perfectly stock Z4 M engine.
Speaking of the stock Z4M headers, while they have a great primary pipe and 3-1 collector design, they still have a rather significant flaw.
There is a 55mm downpipe section, after both the 3-1 collectors, where the diameter of the entire, main pipe is smaller than ideal. This acts as a bottleneck in the exchaust system,
Replacing that pipe section with a larger, unrestricted, 60mm section, would do great.
However, this is a modification which must be caried out by a reputable muffler fabricator only, possibly by a race specialist.
Also, you are right, when you say that the engine will have to be warmed fully, when going to the MOT emission test.
Failing to do so, testing the exhaust gas content with an exhaust system still cold, may spoil the readings.
To be honest, this can happen with the stock cats in place, as well.
As of the the EGT sensor bung, we confirm that we do weld the provision on the left side downpipe, in the proper place, upstream of the cat.
For placing your order, please contact Evolve, who is the exclusive Distributor for the Supersprint BMW exhausts in the UK.
[email protected]
http://www.evolveautomotive.com/
They will be more than glad to assist with your buy, in every way possible.
Best Regards
Alessandro Gilli
Supersprint
Italy
hi Byron
Yes, the Z4M stock cats are 400 cpsi, Not the 200cpsi you are quoting, we have done extensive testing with them.
In comparison to the mainstream, oem ceramic cats, which are 500 cpsi to 600 cpsi, or even more on some cars, they are a huge step forward; but in terms of sheer resistence against free-flowing, they are nowhere near to what the 100 cpsi race cats do offer.
The car manufactures always have to deal with very stringent emnission regulations, and also with lowering the production costs as much as possible, at the same time.
This is the main reason behind the poor design of most of the stock exhausts, excpecially since the late 90s.
In the case of Z4M, BMW did a half hearted attempt, in searching the best performance, by specifiyng a nicely designed, lightweight headers, but choking down its flow potential, by adopting a set of 400 cpsi cats.
It's difficult to speculate how much more hp and torque you will make with the SS cats, on your S/C Z4. But we believe that it will be quite noticeable, no less than that.
We only have dyno charts available for our in-house, back-to-back tests, done on the perfectly stock Z4 M engine.
Speaking of the stock Z4M headers, while they have a great primary pipe and 3-1 collector design, they still have a rather significant flaw.
There is a 55mm downpipe section, after both the 3-1 collectors, where the diameter of the entire, main pipe is smaller than ideal. This acts as a bottleneck in the exchaust system,
Replacing that pipe section with a larger, unrestricted, 60mm section, would do great.
However, this is a modification which must be caried out by a reputable muffler fabricator only, possibly by a race specialist.
Also, you are right, when you say that the engine will have to be warmed fully, when going to the MOT emission test.
Failing to do so, testing the exhaust gas content with an exhaust system still cold, may spoil the readings.
To be honest, this can happen with the stock cats in place, as well.
As of the the EGT sensor bung, we confirm that we do weld the provision on the left side downpipe, in the proper place, upstream of the cat.
For placing your order, please contact Evolve, who is the exclusive Distributor for the Supersprint BMW exhausts in the UK.
[email protected]
http://www.evolveautomotive.com/
They will be more than glad to assist with your buy, in every way possible.
Best Regards
Alessandro Gilli
Supersprint
Italy
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