Fuel prices / efficiency

[David Cooley]

At 03:59 PM 2/18/2000 , you wrote:

>ON-Topic:  I'm building a gas guzzler just as high octane has gone from 1.22
>to 1.65 in 3 weeks!  I see "economy mode" advertised on some of those 16-way
>selector chips. I know there is stuff in DIY archives on efficiency but
>heres my understanding, please correct / add:
>
>-Go for 15 or even 16:1 AFR at light cruise - just don't abuse the car with
>this setup and you're ok.
>-160 degrees Coolant temp is still better than 180 or 200 for economy


higher temp is better for economy... Lower temp is used to fool the ECM 
into supplying extra fuel and make it run richer for more power (or to 
cover up over advanced timing!)


>-higher fuel pressure (for better low load spray pattern) hurts economy at
>idle unless you can tune the idle PW waay down.
>-low tire pressure bad bad bad
>-loose convertors bad for economy  - Lock it up earlier -?
>-good excuse for installing a supercharger - payback is sooner at those gas
>prices!




===========================================================
David Cooley N5XMT Internet: N5XMT at bellsouth.net
Packet: N5XMT at KQ4LO.#INT.NC.USA.NA T.A.P.R. Member #7068
We are Borg... Prepare to be assimilated!
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