Camshaft "shunt?"
Discussion
Hi Guys, i have put a much wilder cam in my 416ci LS3 based Cerbera, gone from 233/237 to 244/257, i also put an aftermarket intake (FAST) and went up approx 50% on injectors, so i am of to the rollers this week to set up. But the rollers dont see everything espesh low down, the 1000-2000rpm cruise settings can be a pain to set up. Has anyone else played around here, and what changes were most successful, eg more or less timing/fuelling. I know its a suck it and see kinda thing, but just seeing what other people might have found. I have altered the compensation settings in my Emerald for the injector upgrade but its less than perfect, but i knew that anyway!
I know this is based on my wildish cammed Rover, but it's worth a go...
Rich (lambda~~0.93) and very retarded timing at part throttle made it a pleasant drive with elimintated shunting, but I couldn't live with the fuel bill or the complaints from people folloing me, or the MOT tester refusing to put his analyser anywhere near the car in case it expired!
So I went for exactly the opposite - a lean cruise with "sensible" MBT based timing, richening up to lambda=1 at idle and a bit richer than that on gentle acceleration. Big engines seem to like running lean on part throttle - It manages engine temperatures very well, and can be used to modulate power output too. Knock is not an issue really until there's significant load involved. The snag is keeping the charge robbing effects of a wild cam at bay - I designed a new intake to help with this. I suggest reading Sir Harry Ricardo's book "The high-speed internal-combustion engine". It was a big eye opener to me.
Rich (lambda~~0.93) and very retarded timing at part throttle made it a pleasant drive with elimintated shunting, but I couldn't live with the fuel bill or the complaints from people folloing me, or the MOT tester refusing to put his analyser anywhere near the car in case it expired!
So I went for exactly the opposite - a lean cruise with "sensible" MBT based timing, richening up to lambda=1 at idle and a bit richer than that on gentle acceleration. Big engines seem to like running lean on part throttle - It manages engine temperatures very well, and can be used to modulate power output too. Knock is not an issue really until there's significant load involved. The snag is keeping the charge robbing effects of a wild cam at bay - I designed a new intake to help with this. I suggest reading Sir Harry Ricardo's book "The high-speed internal-combustion engine". It was a big eye opener to me.
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