exhaust system size answer
Posted: Mon Apr 15, 2002 4:10 pm
Hello Gentlemen (and Ladies),
Wrote to Bob Keller, founder and President of Turbonetics.
Bob was designing, building, testing, and modifying turbo systems before most of you were an urge.
I recant my position about an optimum size exhaust after the turbo, and now maintain that theory only for system size before the turbo.
Following is our exchange
------------------------------------------------------------
Hi Bob,
I am in the middle of a debate prior to a group buy decision for a turbo back exhaust system. In both Hugh Maginnes and Corky Bells books, the emphasis is on exhaust system size before the turbo.
The debate is over the following issues for an exhaust system
A F T E R the turbo:
1) The biggest exhaust practical and hence the least amount of backpressure is better for turbo response,
or
2) there is an optimum size for each engine, which is large enough to be non-restrictive, but small enough to maintain a suitable high gas velocity for best turbo response.
The emphasis is on daily driver low end street response
Please relate your experience to what must be a recurring argument in the turbo world.
Thank you very much
Larry Witherspoon
ssspoon@aol.com
562-982-7720
AND MR. KELLER'S ANSWER
Larry:
The old adage of "bigger is better" is partially right - but HOW you get bigger is just as important. The gasses coming out of the turbo are swirling and don't like to "burst" into
an infinite diameter exhaust system. Ideal expansion of the turbine discharge should involve a 30 degree included angle for minimum loss (15 per side).
After that you can take it as big as you want. Good rule of thumb is to make the turbine back exhaust about 1.5 times the turbine wheel exducer diameter.
Bob K.
------------------------ ---------------------~-->
Buy Stock for $4
and no minimums.
FREE Money 2002.
http://us.click.yahoo.com/k6cvND/n97DAA ... /XoTolB/TM
---------------------------------------------------------------------~->
To unsubscribe from this group, please send an email to:
BC-BFLegacyWorks-unsubscribe@egroups.com
Wrote to Bob Keller, founder and President of Turbonetics.
Bob was designing, building, testing, and modifying turbo systems before most of you were an urge.
I recant my position about an optimum size exhaust after the turbo, and now maintain that theory only for system size before the turbo.
Following is our exchange
------------------------------------------------------------
Hi Bob,
I am in the middle of a debate prior to a group buy decision for a turbo back exhaust system. In both Hugh Maginnes and Corky Bells books, the emphasis is on exhaust system size before the turbo.
The debate is over the following issues for an exhaust system
A F T E R the turbo:
1) The biggest exhaust practical and hence the least amount of backpressure is better for turbo response,
or
2) there is an optimum size for each engine, which is large enough to be non-restrictive, but small enough to maintain a suitable high gas velocity for best turbo response.
The emphasis is on daily driver low end street response
Please relate your experience to what must be a recurring argument in the turbo world.
Thank you very much
Larry Witherspoon
ssspoon@aol.com
562-982-7720
AND MR. KELLER'S ANSWER
Larry:
The old adage of "bigger is better" is partially right - but HOW you get bigger is just as important. The gasses coming out of the turbo are swirling and don't like to "burst" into
an infinite diameter exhaust system. Ideal expansion of the turbine discharge should involve a 30 degree included angle for minimum loss (15 per side).
After that you can take it as big as you want. Good rule of thumb is to make the turbine back exhaust about 1.5 times the turbine wheel exducer diameter.
Bob K.
------------------------ ---------------------~-->
Buy Stock for $4
and no minimums.
FREE Money 2002.
http://us.click.yahoo.com/k6cvND/n97DAA ... /XoTolB/TM
---------------------------------------------------------------------~->
To unsubscribe from this group, please send an email to:
BC-BFLegacyWorks-unsubscribe@egroups.com