Peter Cobbold Posted October 15, 2016 Report Share Posted October 15, 2016 (edited) Hi Peter, I re-set the timing which sorted the pinking. Neil, I set the VE to 100 in the area of the table where coasting occurs. It has helped a lot. But it still wants to shunt while in 4th, 3rd gear under 30mph coasting. Also wants to shunt in 2nd gear slow corners. I'm not sure what going over 100% VE will do. Perhaps I will look a reducing the AFR is that area as well. Cheers Steve Steve, I dont understand. How can you set the VE? I see from Markus' table it is being used as another name for MAP, manifold absolute pressure. But they are not the same. VE , volumetric efficiency will change with MAP and rpm. On other words, for a given MAP, VE will drop at high rpm because cylinder filling doesnt keep up with MAP, and at low rpm when the inlet valve closes late and fails to trap air. For the stock TR6 engine max VE is around max torque rpm, ca 3500rpm. I would invest in a vacuum gauge to measure MAP and an exhaust wideband ( UEGO) AFR gauge. You can then measure both while driving. Then you can tweak the mixture anywhere on the efi map without having to guess at settings. Peter Edited October 15, 2016 by Peter Cobbold Quote Link to post Share on other sites
Steve P Posted October 15, 2016 Author Report Share Posted October 15, 2016 Evening Peter, My software has a VE table. MAP y axis, rpm x axis. I increased the VE values to make the mixture richer is the area where coasting occurs. Steve Quote Link to post Share on other sites
Nick Jones Posted October 15, 2016 Report Share Posted October 15, 2016 If it's like the MS, VE is short for volumetric efficiency but it's a only a notional value and just a way of entering a value for fuelling and can be over 100%. If it works the same way as MS, 100% would be super-rich for small throttle openings. Do you not have an O2 sensor? A wideband O2 sensor makes tuning a hell of lot quicker and easier, possibly even automatic dependent on what your ecu is capable off. Nick Quote Link to post Share on other sites
Peter Cobbold Posted October 15, 2016 Report Share Posted October 15, 2016 Evening Peter, My software has a VE table. MAP y axis, rpm x axis. I increased the VE values to make the mixture richer is the area where coasting occurs. Steve Steve, I see, but its a weird use of VE, aimed I think at getting an air mass flow figure to then set the fuel flow. VE even at its best would be 85% for a TR engine. I guess the table has a notional fixed AFR that resetting the VE value above 85% richens. I agree with Nick a UEGO would allow you to determine that AFR for real. Peter Yes set the 'VE' to make it really rich where the hunting is happening. Quote Link to post Share on other sites
GT6M Posted October 15, 2016 Report Share Posted October 15, 2016 Thanks for all the input. I recently fitted a fast road cam and didn't have time to get the system tuned in. I had a problem with idle and reduced the VE which helped but I guess that has added to the shunting effect. Ahaa, so ye bunged ina hotter cam, moer duration,or just lift If its moer durationee, then ye need t,bung in moer fuel at lower settings aound idle an upto 13-1400 rpms mainly along the bottom VE line 10% line should be OK, butt, I bunged in moer fuel at 800-1600 on the 10% line. As for colde starting / idle, then fuel NEEDS to be took oot esp the cranking fuel reason, the air movement is slower,so fuel kills it by being over richat crank speeds. Also, where is yer Fuel cut off set too. mine is set to nok fuel off above 1100rpms At low throttles, it can jerk a wee bit if not careful wif throttles /revs try disconecting it, see if this cures it And ye may have it set wrong too, like on for TPS and load and revs, cant ev em all, as one is fighting against the others. Disconect the feature, and see if that helps Peter, thee,s are Alpha N systems, wid a throttle pot the fuel is given to what the figure in the box says, there aint no MAP or vacuum in effect here, its just basic look an read tables the image I shown was for ign, but fuel map is exactly the same layoot but in fuel figures needed, no IGN numbers fuel map figs M Quote Link to post Share on other sites
Peter Cobbold Posted October 15, 2016 Report Share Posted October 15, 2016 (edited) Thanks for all the input. I recently fitted a fast road cam and didn't have time to get the system tuned in. I had a problem with idle and reduced the VE which helped but I guess that has added to the shunting effect. Ahaa, so ye bunged ina hotter cam, moer duration,or just lift If its moer durationee, then ye need t,bung in moer fuel at lower settings aound idle an upto 13-1400 rpms mainly along the bottom VE line 10% line should be OK, butt, I bunged in moer fuel at 800-1600 on the 10% line. As for colde starting / idle, then fuel NEEDS to be took oot esp the cranking fuel reason, the air movement is slower,so fuel kills it by being over richat crank speeds. Also, where is yer Fuel cut off set too. mine is set to nok fuel off above 1100rpms At low throttles, it can jerk a wee bit if not careful wif throttles /revs try disconecting it, see if this cures it And ye may have it set wrong too, like on for TPS and load and revs, cant ev em all, as one is fighting against the others. Disconect the feature, and see if that helps Peter, thee,s are Alpha N systems, wid a throttle pot the fuel is given to what the figure in the box says, there aint no MAP or vacuum in effect here, its just basic look an read tables the image I shown was for ign, but fuel map is exactly the same layoot but in fuel figures needed, no IGN numbers fuel map figs M Markus, Thanks. Steep learning curve for me. I didnt realise there's no feedback from MAP, it runs on just rpm and TPS.. Peter Edited October 15, 2016 by Peter Cobbold Quote Link to post Share on other sites
Steve P Posted October 15, 2016 Author Report Share Posted October 15, 2016 Hi Nick, I've sent you a pm. Steve Quote Link to post Share on other sites
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