Megasquirt talk (split from robokills project thread)

[NoHachi]

Skassa: 12 vs 17 ignition map settings..cruder indeed..but that is already 12x12 individual map cells you would have to specify..now some of those will never occur in practice, but that still leaves about 100 map points that need tuning..now look at the 17x17 map. Thats 289 map points..say around 200 when you don't count the very low rpm/full throttle etc ones..Will you be tuning each individual cell in that map? I won't for sure..but the engineers at toyota (will and do so).

Coolant temperature correction? You only run that while the engine is warming up. Most people accept somewhat lumpy running if it is during startup only. Overtemperature map..safety feature that you lose..Applicability to a tuned engine might be doubtfull.

TVIS activation? you would need to hardcode that into the MS map..think it will run smoothly even without the delay option.

As fas as the idle routine goes..these kinds of things can be programmed into the MS2 without problems..there is room enough. I do have to say that these algorithms focus on 2 or 3 sloped areas in the VE map that allow stable idle conditions (downward sloped section of the VE map). The rpm points where these occur will have completely changed on a tuned engine..so it degrades to just a catch routine.

Thats my doubt with the unichip thing..If I could alter all the settings etc myself whenever I needed and understood all the toyota maps: fine Dunno whether that is the case though..If all these extra settings are not touched, then they might be completely inappropriate for the new engine you just created..they're there, but they're not helping anything.

[wouter86]

to completely change the subject...

I now have a megasquirt with a V3 board lying around here with a stimulator (so if someone wants to build one, you can lend mine) and I was planning on building a jumper cable so I can plug and play it in the original 4age wiring loom.I've been reading a lot and found a site that describes how to make that jumper cable.

All the sites i saw that have write-ups on how to make a jumper cable for a 4age engine are based on engines with an AFM.Does anybody know if there are walkthroughs for MAP based 4age's?Because the plug on the AFM also contains fuel pump control and the air intake temperature sensor.

Also the writeups for AFM 4age engines mention that the ignition part of the engine has to be the VAST ignition system and not ESA.I could not find a clear answer on how te determine which system is used in the european 4age map based engines.It has something to do about 4 or 24 wheel teeth.

Did anyone ever make a jumper cable for a 4age map based engine?

Small noob question.The megasquirt has 3 connectors, a db9 connector for the connection to the pc.A db37 connetor for the wire loom in the car but there is also a db25 connector available.What is it's purpose .

I know that the MS probably won't be running the engine better than the stock ecu, but i just wanted a project i could learn something from and since there are a lot of maps available for the stock engine i thought this might be a nice project to start with.And a free programmable ecu is a nice base for tuning.

[jamiemirror]

Quote:Did anyone ever make a jumper cable for a 4age map based engine?

Contact BadDog in this forum.

[PetzK]

Where can I find more info on that Unichip... is it any good or not? for running ITB's with cams

[BenR]

piggy backing an ECU to run a higher overlap cam on throttle bodies will lead to pretty poor running.

When it comes to making an engine drive smoothly and loveingly, its all about the ECU's capabilities (and you get what you pay for) and the mapper.

In my experience, if its a high rpm engine i wont use anything less than 25x25 breakpoint map, anything less and you just asking too much in terms of interpolation which will simply lead to 50% of your engine running on averages between two mapped points, which is not really what we are trying to do when we spend all this time and money mapping to make sure every rpm of the engine is running spot on for fueling and ignition.

Tuning ignition timing is another grey area. When i see people simply advance until they get knock then retard a little, i cringe. This is not the best area for peak BMEP. You will want to monitor knock, AFR and EGT minimum. And EGT must be from 3-4" behind the exhaust port, not at the collector as you want to collect true data of the combusiton temps and see if the mixture is burning correctly. Ideally you will want to see 12.9-13:1 AFR and 1300-1350 degrees F for EGT.