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Subject:Re: Intake air flow, improvement possible?
From:Al and Sue Brase
Date:Sun, 28 Nov 2004 11:37:21 -0600

Jim:
I agree completely, and you don't have to convince me that the LMMU is a
good idea. I wrote earlier:
"Actually, fuel consumption MIGHT improve slightly due to more accurate
mixture control. "
When I wrote about compression ratio improving fuel efficiency, I should
have been a little more specific and said that was the only thing that
would improve fuel efficiency under all conditions.
Al Brase

Bostig Engineering wrote:

>>The only simple thing that will decrease the fuel consumption would be
>>to raise the compression ratio.
>>Al Brase
>>
>>
>
>
>Hi Al,
>
>Think about this scenario for second though, suppose you're running rich,
>perhaps an A/F of 11.. if you change the value to say 13, will you not
>both raise horsepower and lessen fuel consumption? Now in the real world,
>people tend to get on whatever horsepower they have available(which tends
>to mask any increase in efficiency), but in some cases (long distance,
>easy driving) you are going to see the opportunity for better efficiency,
>unless of course you end up driving faster since it is possible. The key
>is not *only* reducing pressure drop in the intake, but ALSO measure the
>air mass accurately, AND provide tunability. It is this three pronged
>approach, all addressed by replacing the stock system that the gains are
>realized. And as with any engine system, the gains are complimentary, for
>instance I'm quite sure that the gains had by a big valve engine will be
>greater than for a stock engine, because there is more potential still
>choked up by the restrictive intake, and inacurate air metering.
>
>Thanks,
>
>Jim Akiba
>Bostig Engineering
>
>
>