Spent some time looking around. And I didn't come out with anything. There is a lot of Req_fuel mention. But I don't think its the user variable. I don't know how the req_fuel variable we can edit goes down into the code but there is a lot of calculation about req_fuel. So no answer yet.

No, on ms2 corrections are all percentage based except cranking fuel which is derived from reqfuel. That is literally it, cranking pulsewidth percent. Deadline has nothing to do with it Lol.

You are wrong Pat.

I am sending my MS to Brain. It needs a check up, just so I can be certain that it is working correctly. If it is, well then I'm dead in the water again.

New question for you guys. The V Band assemblyS that were sold to me with my ARtech downpipe and exhaust, have this little ring. It is the gasket I suppose. When I drop it into its slot, there is a small gap still between the two ends of the ring. Is this for thermal expansion? I just don't see it growing 1/8" . Wouldn't this just play games with the O2 sensor , these little leak paths?
https://www.miataturbo.net/attachmen...ine=1445375927

I've never used a gasket on a V-band before. I always just surface the flanges after welding to make sure they are flat, and bolt them together. No leaks. Are your flanges warped by chance? Maybe that's what that gasket is for, though I agree an 1/8" gap seems like that would leak too...

This function calculates injector deadtime:

Post a picture of the v-band flanges. They sound like they are cut for an o-ring. In which case you need that.

I don't know what any of that says, I suck at anything to do with code. But I didn't mean that dead time is affected by req fuel (those are two diff things of course). What I was getting at was, would having the wrong req fuel cause tuning problems at low PWs due to injector dead times being a big factor at low PWs. I dunno, just a thought.

I have had no problem running my car with the correct req fuel settings with MS3, so I'm not going to change it for whatever benefit Deezums believes exist by doing so.

Deezems just said cranking fuel is affected by req fuel, so there's something I guess. But I'm sure you can tune around that if it's the only thing affected by the change.

Actually sorry Ryan for all this crap in your thread. But as mentioned, I too am curious to see your V-band flanges. I've never seen one made for a gasket.

Deadtime is measured in pulsewidth and is subtracted from whatever current pulsewidth fueling the megasquirt has decided is required.

How do you not know that? Reqfuel has nothing to do with deadtime and will not change how much latency is subtracted from all your fueling calculations. Do you even know how megasquirt works??

Reqfuel is a MULTIPLIER of VE cells. Multiply. Nothing more. If you have double the reqfuel, it sprays twice the fuel so you can half the VE values. If anything else is based off VE, like percentages as 99.9% of corrections are, it matters not what reqfuel is. If it's based off reqfuel, it will specifically say so in the tunung dialog. Cranking is the only one, because there's no map, no RPM and you basically just squirt a fixed PW till it fires. I see no reason why any other correction would need to be based on reqfuel.

I just read through all your troubleshooting. How is the ECU wired to the car? Seems like you are having multiple issues making troubleshooting more difficult. Wouldn't hurt to have the ECU checked out, but it seems there may be a wiring problem perhaps?

Thanks for attacking me. But yes, I know how it works, have had MS on my car since 2007. I didn't write the code so I don't know when/where it's used. In the past, (2008 MS2E) it was used in multiple places and it was known that having the req fuel wrong would cause other issues (mainly in accel enrichments and startup/warm up) Perhaps that's no longer true, I have no idea. You seem to be certain it's no longer an issue.

I would agree with you, except that I now have a dedicated wire from the o2 sensor to the ECU pink wire. I also get the 0 to 5 volt fluctuation based on the AFR reading, but ts just sees garbage.

How is the ecu wired to the car?

Flange with a definite cut for something. ..all of the joints use this same aluminum thing.

https://www.miataturbo.net/attachmen...ine=1445378357

So you had a ms2 that used reqfuel based enrichment on warmup, not a percentage multiplication of the VE table? You sure you know how megasquirt works? Would you find me a screenshot of a warmup enrichment plot that is not percentage based?

Again, you had a ms2 that had reqfuel based accel enrichment? Not a percentage based multiplication of the VE table, or an accel pump direct pulsewidth adder? Again, I would like to see this.

You've clearly no clue what reqfuel does, and that's why I attack you. If you are going to post like you know stuff may as well be prepared to verify what you are saying. Instead, it's a mystery number to you and therefore it's not to be adjusted. That's not the case, and that's what I'm saying, it's a super simple global multiplier, that's it.

I used a MS2E way back, now I have a MS3 PRO since 2013. I didn't write the code, I promise. I read on msextra forums that having the wrong req fuel caused other issues than just tuning the fuel table. Some people could dial the fuel in when hot, but when cold the car would crank and die, or hesitate on throttle input, etc, problems during warmup. And it from the req fuel being off and the ECU used that.

I will tell you I don't write code, and I can't read that stuff Adian posted either. That I am ignorant on. I do know the basic fuel equations that you know and have posted here. And I've tuned long enough to know how to make my car run well under all conditions.

If it's a super simple global multiplier and you know what you're doing and your car runs better now with a different req fuel, great. It wasn't always like that though. No need to attack someone for telling you this. It's not helping anything.

Yeah that looks different than mine, mine are just flat with no cut like yours shows. On yours, are both sides the same, or one flat and one cut like that for the gasket?

If I run a proper, calculated reqfuel I get PM's from you asking to fix my tune as my VE values are too damn high, no way it runs right!

All of the cold enrichments on a MS2 are percentage based, ASE and warmup. You can read anything on the internet, it's just your job to filter out the bullshit. If you spread bullshit, fuck you.

If one can, in static running conditions, half reqfuel while doubling VE to have the same total fueling, and all modifiers are percentages of the VE value, all multiplications/enrichments must be the same.

Lets say reqfuel 5.0 idle VE 50. Now, reqfuel 2.5, VE 100.

Warmup, 110% at 160f.

50x1.10 = 55
100x1.10 = 110

Look, our warmup VE values are identical still, they are proportionally the same!

So please, quit spreading the bullshit.

Sooooo, how 'bout that V Band flange? Yes, both are cut to accept the ring thing. It also uses this monstrosity of a clamp. Like solid stainless on a single hinge on one side, nut and bolt on the otber. Doesn't look cheap. Doesn't necessarily look right either though

Plumbing waste pipes use Vbands with o-rings. I consider using one for EWG purposes but eventually found a correct size exhaust v-band for the same cost. That said, I did manage to find copper o-rings that looked like a fit on paper. So there may be something out there.

Ehh, I don't think that a well known fabricator would use sewer V band assemblis on an expensive exhaust.