Test pipe - fuel consumption?
Test pipe - fuel consumption?
(OP)
On another forum I regularly visit I came across an interesting thread, when replacing the catalyst for a less restrictive hollow test pipe will increase or reduce mpg?. So which one is it, I am curious to hear your answers. Thanks





RE: Test pipe - fuel consumption?
In practice it seems daft to chase a few % improvement in mpg in exchange for a large fine... but that's your choice.
Cheers
Greg Locock
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RE: Test pipe - fuel consumption?
This might partly offset the gains from lower blow down pressures.
Regards
eng-tips, by professional engineers for professional engineers
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RE: Test pipe - fuel consumption?
Relative to a modern high flow converter in good condition I don't think you'd be reliably able to tell the difference (your driving probably varies more widely). Aftermarket high flow units can flow over 500 cfm (some well over that figure), which indicates a level of backpressure comparable to (and quite possible lower than) a high performance aftermarket muffler.
Norm
RE: Test pipe - fuel consumption?
-Reidh
RE: Test pipe - fuel consumption?
Cheers
Greg Locock
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: Test pipe - fuel consumption?
How can a cat increase back pressure but not have an acoustic effect? We don't actually deal with catalytic converters in our industry, so I am by no means an expert on the subject. I had assumed that if it has enough restriction to affect back pressure that it would change the effective length of the pipe.
Reidh
RE: Test pipe - fuel consumption?
I should have said no significant /measurable/ effect.
Yes, obviously it has some effect.
Cheers
Greg Locock
Please see FAQ731-376: Eng-Tips.com Forum Policies for tips on how to make the best use of Eng-Tips.
RE: Test pipe - fuel consumption?
You will have more power availiable, therefore the fuel consumption will go up. Of course in a steady loading condition, you will have the same or slighlty better fuel economy at less throttle openings.
RE: Test pipe - fuel consumption?