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blueflame · 03-08-2009, 09:25 AM

Do timing changes occur too via ecu? I'm not familiar with them.

My naturally aspirated carb Citroen Ax has no ecu or even a temp gauge, and I have had to advance the timing slightly as the vacuum advance is kaput and all the other vacuum units at the wreckers were kaput and my other 2 AX have kaput vacuum advance units too...so rather than replace the Bosch distributor with other brand/type and and .... I live with it and have advanced the ignition timing slightly.

I have a manual air intake flap that is lever operated under the hood. This can have either cool or hot air, or a combination of both - 50/50.

Going up mountains in warm weather I often kill the stereo and listen to the engine for detonation by depressing the throttle quickly thereby increasing load... then listening for any detonation which will occur if I ascend too quickly and/or in too high a gear.

Dropping speed and selecting a lower gear will cease detonation.

Yesterday I traveled with surfboards on the roof and 4 people in my 954cc 45hp Citroen, and after 10 minutes pulled over and went to 100% cold air (was a hot day anyway so not that cold!), as performance was crap and detonation was occuring on the flat at 90km/hr. Detonation then ceased. Returning back home in the evening with the cooler night air I went back to 100% warm air and experienced no detonation even ascending mountains at speed. FE was at least 60mpgUS for this mostly highway journey @ 90-100km/hr.

In my case I have had to determine the amount of WAI my vehicle will tolerate by trial and error, even without a temperature gauge. No music and a feel for engine power output is important during this appraisal time. And calculating in various loading considerations of speed, weight of cargo, outside temperatures and incline. Instrumentation would be handy to say the least, but this way kinda brings you in rhythm with the engine and its 'sweet spot'.

I have found WAI to add around 10% to my FE in the Citroen compared to CAI, during this summer, so I use it as often as I can.

03-08-2009, 09:25 AM	#13 (permalink)
blueflame Master EcoModder Join Date: Nov 2008 Location: Auckland NZ Posts: 333 Thanks: 7 Thanked 13 Times in 10 Posts	Do timing changes occur too via ecu? I'm not familiar with them. My naturally aspirated carb Citroen Ax has no ecu or even a temp gauge, and I have had to advance the timing slightly as the vacuum advance is kaput and all the other vacuum units at the wreckers were kaput and my other 2 AX have kaput vacuum advance units too...so rather than replace the Bosch distributor with other brand/type and and .... I live with it and have advanced the ignition timing slightly. I have a manual air intake flap that is lever operated under the hood. This can have either cool or hot air, or a combination of both - 50/50. Going up mountains in warm weather I often kill the stereo and listen to the engine for detonation by depressing the throttle quickly thereby increasing load... then listening for any detonation which will occur if I ascend too quickly and/or in too high a gear. Dropping speed and selecting a lower gear will cease detonation. Yesterday I traveled with surfboards on the roof and 4 people in my 954cc 45hp Citroen, and after 10 minutes pulled over and went to 100% cold air (was a hot day anyway so not that cold!), as performance was crap and detonation was occuring on the flat at 90km/hr. Detonation then ceased. Returning back home in the evening with the cooler night air I went back to 100% warm air and experienced no detonation even ascending mountains at speed. FE was at least 60mpgUS for this mostly highway journey @ 90-100km/hr. In my case I have had to determine the amount of WAI my vehicle will tolerate by trial and error, even without a temperature gauge. No music and a feel for engine power output is important during this appraisal time. And calculating in various loading considerations of speed, weight of cargo, outside temperatures and incline. Instrumentation would be handy to say the least, but this way kinda brings you in rhythm with the engine and its 'sweet spot'. I have found WAI to add around 10% to my FE in the Citroen compared to CAI, during this summer, so I use it as often as I can. Last edited by blueflame; 03-09-2009 at 03:18 AM..