Author Topic: improving fuel economy? (Read 5202 times)

126dave · « **Reply #15 on:** August 30, 2008, 07:25:05 AM »

hi guys,just a comment on mixture etc...dont forget that the fiat aircooled uses a slightly rich mixture for cooling purposes, iread this in some respected tome...buggered if i can remeber where tho :roll: .....so dont go too lean....

phreak97 · « **Reply #16 on:** August 30, 2008, 12:34:50 PM »

how does it do that? and how do i tell if it's too hot? lol

126dave · « **Reply #17 on:** August 30, 2008, 01:05:36 PM »

mmmnnn, check out the blitz buggy tunin pages i think it was on there someplace.......

the richer mixture just makes the head run cooler......lean burn is always hotter.....the fiat engineers richend the top end mixture so the engine could run flat out with 4 fat italians in the car and not burn valves or pistons.....

as far as im aware all aircooled engines run richer at the top end for the same reasons.....of course im prepared to be shot down in flames by someone hehehe

fightingtorque · « **Reply #18 on:** September 01, 2008, 12:00:55 AM »

Hi guys,

I was talking about my work on the Bis, I don't know about the air cooled, but as said above, air cooled engines are generally designed to run rich under high load conditions to help cool the engine. If the air cooled 126 has a twin choke progressive carb then it may be lean on the primary, but if it doesn't then I would guess it is fairly lean all the time.

Wideband lambda - I am using Innovate Motorsports products bought from graham goode racing but we are also about to try some cheap kit built ones we got from a guy in canada (found it on the net somewhere).

The fuel injection I am going to put on is a product we are developing for low cost motorcycles and utility engines, just thought it would be fun to try it on a 126. I will post details when it's done.

Someone pointed me to a link a while back where a polish guy has put a megasquirt controlled system on a bis using the throttle body injection parts from a cinquecento.

126dave · « **Reply #19 on:** September 01, 2008, 06:19:04 AM »

ah sorry, i jumped in without reading the whole post...my apologies....

M'coli · « **Reply #20 on:** September 13, 2008, 09:53:58 PM »

Quote from: "phreak97"

i dont know anything about primary and secondary chokes, or lambda sensors.. fitting fuel injection sounds like a fun idea.. it would certainly be unique among my local fiat 500 club. i'd imagine theres a fair bit of modification involved though? where are you going to find a fuel injection system for a 2 cylinder? and how does it connect up?
and most importantly, how much would parts for such a thing cost?

Basically, the twin-choke carb is set-up to allow excellent fuel economy so long as you aren't trying to go too fast, whereby the second choke richens thing up. If you've got one of these engines, fit a stronger spring to the second choke so that you know when it's open.

phreak97 · « **Reply #21 on:** November 05, 2008, 05:56:51 AM »

i've had my oil breather filter on for quite a while now, and i havnt really noticed a change in economy, but i never actually took any numbers down. it has leaked a little bit onto the rocker cover and the area around the carb, but it only did it after some high speed country driving (doing over 100km/h)

i have used the heater and not noticed any oil vapor coming in, but i'm using synthetic oil which doesnt seem to give off particularly nasty fumes even when dripped on the exhaust..

i dont know how to tell if the car is happier or not..