Rookie Posted July 20, 2015 Share Posted July 20, 2015 Kpr explained pretty well how to road tune ignition without a knock sensor. But if you are referring to a knock sensor as something to detect knock, then I will agree that it is nice to have. Quote Link to comment Share on other sites More sharing options...
BlownCorona Posted July 20, 2015 Author Share Posted July 20, 2015 yeah thats a pretty good run down of what i need to do, and it just so happens in 2 days we are running drags down the runway. so i should be able to do a fair few timed 1/4 mile runs and fiddle with it. and i figured id add a knock sensor because the ECU can handle it and take care of the engine if for some reason it ran into a parameter that caused knock etc etc Quote Link to comment Share on other sites More sharing options...
kpr Posted July 20, 2015 Share Posted July 20, 2015 Listening for knock with your ears, via some kinda amplification device is always best. 1 Quote Link to comment Share on other sites More sharing options...
downtrail Posted July 20, 2015 Share Posted July 20, 2015 You can also use a program called virtual dyno for your advance tuning. If you set it up right its pretty dam close all you need to do is log a wot run in probably 3rd for the road. Open the log file with excell and trim it from say 2.5k to or 8(or whatever your running it to) open the log in virtual dyno anf itll spit out a chart. Do it for every extra deg of timing you add and watch it untill it stops making power then drop it back. You can also observe what adding in or taking out does for the lower end of the motor. But to be as accurate as possible it needs to be repeated on the same piece of road or whatever. Start logging Go through the gears untill 3rd cruise at 2k untill such point then plant it. Keep it planted untill you hit your upper limit. Trim log open changa timing repete etc. 1 Quote Link to comment Share on other sites More sharing options...
cute wee gem Posted July 20, 2015 Share Posted July 20, 2015 I agree with these other chaps. I'm willing to bet you could throw a lot more timing in under full load. I ran more timing with 12psi in an old engine of mine. 20deg @ 12psi from memory. Another I think was around 23deg @ 8psi. Both engines were on factory cast pistons that are notorious for cracking in these particular engines. You should be 28-32ish on 98 surely. Quote Link to comment Share on other sites More sharing options...
downtrail Posted July 20, 2015 Share Posted July 20, 2015 Oh definitely you can crank heaps more in some of the rbs ive done are at 20deg on 14psi. Also make sure you set your hardware latency properly if you haven't already done so. export your table and save it. Then set the entire table to 10 deg. Set your timing light up and rev motor to say 3k you'll notice the timing wandering either direction. Adjust the hardware latency untill its rock solid at ten degrees. Really important with megasquirt as they do wander around a lot if not set properly. You may end up with 30deg when your map says 20deg etc 2 Quote Link to comment Share on other sites More sharing options...
BlownCorona Posted July 20, 2015 Author Share Posted July 20, 2015 how do i adjust the latency? and yeah as you've all noted, i can chuck a bunch more timing in under load, this was just a super conservative map for driving around the carpark in, ive already bumped it up closer to the 35 mark under load. Quote Link to comment Share on other sites More sharing options...
downtrail Posted July 20, 2015 Share Posted July 20, 2015 its under basic -> advance code options, adjust it up slowly until the timing stays constant through the rev range, Quote Link to comment Share on other sites More sharing options...
BlownCorona Posted July 21, 2015 Author Share Posted July 21, 2015 got it. i kept going up till it was pretty steady at 3. does that sound reasonable? it wanders a degree or so each way at lower RPM and then cleans up around 2k so this seems fairly safe to me. also went out for a proper drive and had a fiddle with the map. ive now got this. i know its not as agressive as i can go, but ill leave that for when ive got some real spare time and a nice stretch of road, and follow the above instructions. its certainly a lot faster, much faster than i ever would have thought this engine would go enough for me to think ill need to look at upgrading the brakes,smooth power delivery right thought the rev range. also i set up launch control. its good for a laugh! will need fine tuning but also apears to work very well indeed Quote Link to comment Share on other sites More sharing options...
downtrail Posted July 21, 2015 Share Posted July 21, 2015 Pretty good considering there are only 4 refrence points for it to calculate the ignition angle at. After around 4000rpm you probably want to stop the timing incressing under load but rather have it flatten off. But every motors diffrent it may well love being feed more. Quote Link to comment Share on other sites More sharing options...
BlownCorona Posted July 21, 2015 Author Share Posted July 21, 2015 i did notice i wasnt really using much over 4000rpm unless i made a note to rev higher. whether this was because of the road i was on having too many turns, or because the rev characteristics made me feel like i should shift there i dont know, but will know tomorrow when i do some 1/4m passes on a flat runway. quite interested to see what sort of time it will post Quote Link to comment Share on other sites More sharing options...
Roman Posted July 21, 2015 Share Posted July 21, 2015 Jeepers I'm only running 22 degrees at 6000 and my max is 23 degrees at 8000. Although at a guess EGTs are going bananas, if we are taking cues from the 02 sensor cutting out sometimes and my alternator melting. Quote Link to comment Share on other sites More sharing options...
BlownCorona Posted July 21, 2015 Author Share Posted July 21, 2015 though you have a really high compression 4 valve engine with probably fancy pistons. since my engine is pretty basic it takes higher advance values to achieve the correct results Quote Link to comment Share on other sites More sharing options...
yoeddynz Posted July 21, 2015 Share Posted July 21, 2015 Id have thought you'd (Dave) would be running much more advance on your beams engine? Quote Link to comment Share on other sites More sharing options...
Roman Posted July 21, 2015 Share Posted July 21, 2015 Hmmmm flipping back through some notes it looks as though the reccomended settings from Glenn say it should max out at about 28 degrees instead of 22. So maybe I was just too chicken to advance it further without some form of knock monitoring.It's a work in progress haha.38 degrees advance still seems like heaps though! Quote Link to comment Share on other sites More sharing options...
BlownCorona Posted July 21, 2015 Author Share Posted July 21, 2015 i was led to believe the max advance was under load conditions? and under no load it can handle way more? Quote Link to comment Share on other sites More sharing options...
BlownCorona Posted July 21, 2015 Author Share Posted July 21, 2015 that being said, ill eventually be running around 35 max advance under load i think. and possibly closer to 40 off load, but research and testing will be required. this is particularly why i enjoyed installing the megasquirt, how many people really understand whats actually going on inside their engine! this forces you to learn Quote Link to comment Share on other sites More sharing options...
anglia4 Posted July 22, 2015 Share Posted July 22, 2015 I don't want to start a whole new thread but I'd appreciate some MS guru's chiming in on my build: //oldschool.co.nz/index.php?/topic/47057-anglia4s-1968-ford-mustang/?p=1557278 I really still have no idea what I'm looking at/talking about Quote Link to comment Share on other sites More sharing options...
Corbie Posted July 22, 2015 Share Posted July 22, 2015 ken to see a step by step basic tuning tutorial put together from information across the multiple projects on here. a quick troubleshooting guide would be awesome too. seems like a few people have a lot of knowledge on making these things run. 1 Quote Link to comment Share on other sites More sharing options...
BlownCorona Posted July 22, 2015 Author Share Posted July 22, 2015 im more than happy for this thread to turn into a general help me with megasquirt thread. i stupidly forgot to take my laptop out to the drags today so couldnt really edit anything. but here's a video of one of the runs. sounds pretty great. though power does suddenly flatten out at somewhere around 4500-5000 RPM. so ill need to log some data and see whats going on around that area. there is another clip a friend took of my launching, and it just makes me smile every time, the chatter of launch control and then a small amount of wheel spin just made it looks like such a performance car. ill upload it for kicks when i get it from him Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.