Leafy wrote:Swank Force One wrote: Not really but I wouldn't think it likely because it seems to be pressure related. Oops got ninja'd by leafy. He doesnt have a crank trigger fwiw.He must have a crank trigger even if its works like the miata CAS he still has a crank trigger or the damn thing wouldn't run at all.
He's running essentially a 24-1 trigger wheel off the cam in a gutted distributor housing.
Replaced coil still no change :-/
I'm going back to the VE table being garbage, but have no idea how to fix it.
got back in touch with Matt @ DIYAutotune. Sent him a couple logs. Hoping he can help me get this thing lined out.
It doesn't look like an RPM input problem. I'd check to be sure the timing doesn't have any latency issues.
So no noise issue causing this? what latency setting should I try?
Whatever latency gets the timing to hold steady from idle to 6000 RPM with timing in Fixed Angle mode.
not to sound dumb, but how do I get timing into fixed angle mode?
Basic settings > more ignition options > fixed advance
Change from "use table" to "fixed timing."
I'd imagine you'd probably just want to stick it on the base timing just for testing purposes.
I'll try this later this evening
Just to put this to the top for reference...
I called someone i knew had run Megasquirt on one of these motors in a similar config (hacked up distributor), and turns out they had the same exact issues they fought for months.
What's happening is that the VR signal is garbage. From their experience, no amount of shielding or soldering in filters will fix it.
Basically it took two things:
1) Adjust the pickup in the distributor until is about a paper's thickness away from the teeth
2) Adjust the "VR dashpot" (I'm not entirely sure what this is, but he said it looked like a tiny white "relay thing" with a small brass screw on top of it.) until the signal doesn't look like a toddler got ahold of some crayons. No real way to tell which way it needs to go based on logs. Just trial and error.
He also suggested using stock heat range Champion Copper plugs gapped down to 20-22, but i'm not sure i'd do that.
In reply to Swank Force One:
Was he using an o-scope to check signal out of the sensor or reading through the MS?
My F2T loved it some NGK V-Grooves, I tried a couple other plugs and none ran as well, I wouldn't recommend Champions in this app either.
He was logging VR through MS.
I only use NGK Coppers in these cars. Dan is running the same plugs i do now, ZFR7F11s.
The data log I saw didn't show any loss of sync issues.
So the VR looked exactly as it should? 
If that's the case, i'm going to start putting together an FCON for this car tonite. 
I'm going to lower the gap on the plugs in a bit. He sent me a Ve Table for 440's (I'm running 460's) and a timing map. At idle my car was ignition should have been at 9-10, but it was at 17.5. That said I plulled #1 piston and upon checking TDC the cam was on the correct mark, #1 @ TDC my dizzy was off slightly so using a timing light I set it at 10* and loaded the timing map I was sent.... HUGE difference!!!
It PULLS much better than before, which leads me to believe that it definitely could be spark blowout. Report back in a bit!
Make sure you get that timing sync'd up properly. If the MS value != to what you see on a timing light, stop and get it that way before doing anything else.
Well i am really late to this party but i just read the thread and watched the videos.
I didnt look at any of the logs. From what i can tell, you guys are just passing around fuel-related logs when there are videos clearly showing a good AFR as the problem is occurring.
My own experience with widebands has been that engines dont flood out under WOT until the ratio is somewhere on the rich side of 9:1. It could be 6:1 for all i know since all my widebands stop at either 9 or 10. When a WOT engine 'floods' it just loses power evenly and smoothly. When an engine leans out at WOT it gives you a lot of misfires and motion to let you know. But neither one of these things is happening anyway. The AFR is not the problem. That also rules out the pump, regulator, and any pressure issues. I dont think it is a fuel issue at all.
I think your total timing is going close to 0 or even PAST tdc. Maybe this was covered in all the logs i didn't look at, but if not, i would definitely look at it.
No EGT on this car, right?
My timing mark has shifted (rubber on crank pulley) moved in relation to the inner part of the pulley. I made a new mark by putting a long screwdriver down #1 so the timing is set to 10*. I changed the MS spark table to one supplied to someone Ben introduced me to. It runs MUCH better now, but still cut out over 10psi.
Well, base timing is never going to change while the engine is running unless a bolt comes loose so i'm more worried about the timing the computer has control over. Can you watch it live?
Yes.
dansxr2 wrote: My timing mark has shifted (rubber on crank pulley) moved in relation to the inner part of the pulley. I made a new mark by putting a long screwdriver down #1 so the timing is set to 10*. I changed the MS spark table to one supplied to someone Ben introduced me to. It runs MUCH better now, but still cut out over 10psi.
Ugggghhhhhh....
I'll bring another pulley to the Challenge.
I am wondering if it is not the MS but something with the motor (plugs wires etc) I have not gone back through this can you point me at a log file that I can look at?
Just so I understand. No boost or boost under 10psi and all is good. It will go to red line. Over 10pis and it falls on its face over 4500RPM
What FPR are you running?
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