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He already has Incone studs, because he purchased a turbo kit from the shop that pioneered the use of Inconel studs in turbocharged Miatas. Your concerns are not relevant to this thread.
If Req_Fuel is reset properly, the changes in the VE table should be small, not 50% change. This presumes the original Req_Fuel was correct, and not fudged.
After putting in the injector size, did you click the "Required Fuel" button and make sure both boxes show the changed value?
Yep that did it... didn't realize that had to be done as well. Much closer on the old fuel map now.
Now, this is kind of strange. On a restarting at temp after sitting for ~10 minutes it dies instantly unless I give it throttle, and then it runs really lean for a while (ase / wue?). Once it's been running for ~30-45 seconds it idles just fine at 14.7. If I kill it and restart immediately it's fine. Will need to investigate more but the laptop battery died. I see the table for cranking IAC duty cycle - is the crank-to-run time supposed to be the delay from that to closed-loop idle?
Life pro tip: remember to tighten your lugnuts before driving off.
I am slightly ashamed to admit, I have done this before.... Happened with a customers minivan a few years back, thankfully i only got a couple hundred feet, and heard the clunking of the rims loosening against the hub!
The lean hot restart is a thing. Something heat soaks. I have yet to do the research to figure out the solution yet. I know other people here smarter than I know how to fix it, but wanted you to know you are not going crazy.
I did not see them listed in his parts list and I was not aware that your package came with the studs.
No worries Yes, in the past, turbocharged Miatas have not been the most reliable things out there. I set out to change that with my turbo kit, calling on a decade of experience with turbocharged Miatas of all shapes and sizes. If you start with quality components designed by someone with a decade of experience building race-grade turbocharged Miatas, you may discover that the end result is substantially more reliable than your average steel-stud cast-iron turbo setup.
The lean hot restart is a thing. Something heat soaks. I have yet to do the research to figure out the solution yet. I know other people here smarter than I know how to fix it, but wanted you to know you are not going crazy.
Yeah, I had the problem solved before. Just trying to figure out now that I've got new injectors and a lighter flywheel how I should fix it. IAT heat soak wouldn't have changed from before (the typical problem that causes lean hot restart)
I have the Yellow's, which are notorious for hot restart. Had some hopes that going to a return type fueling system on my 99 would help. It did not. There have been some hints that the FF 640's have some of the issue as well. Here remains my fix, and it works pretty well. Taper is in Cycles, not Seconds (set at bottom of "Cranking/Startup Settings" ASE Count Units):
By the time the taper ends at high temp, EGO has taken over. EGO has 15% authority in the idle range.
Last edited by DNMakinson; 02-16-2017 at 05:06 PM.
Reason: Added FF 640 comment.
Thanks for posting those up. It seems to have helped a bit - still feels like a bit of a bandaid, and I have some tweaking to do but it's in the right direction for now.
Anyone running a Ford or GM MAF on their turbo car?
Thanks for posting those up. It seems to have helped a bit - still feels like a bit of a bandaid, and I have some tweaking to do but it's in the right direction for now.
Anyone running a Ford or GM MAF on their turbo car?
Yes, it's a bandaid, but I don't know of any other control method available in MS3. And realistically, this is an issue that occurs fairly infrequently, and for short duration. One other thing I have considered, but not tried, is to allow the fans to run with engine off. Unfortunately, this would be of little value because the key must be ON.
There's a checkbox to ignore MAT readings during start... will give that a shot. I wouldn't call it infrequent though - I spent all day yesterday in town with the car and every start required some throttle to keep the RPM's from dropping too quickly after the first "light." I'll try to get it on a log this evening.
There's a checkbox to ignore MAT readings during start... will give that a shot. I wouldn't call it infrequent though - I spent all day yesterday in town with the car and every start required some throttle to keep the RPM's from dropping too quickly after the first "light." I'll try to get it on a log this evening.
Agreed, worth taming.
Check your MAT correction table. It should be almost flat at 100% from 70*F and higher. Therefore, it should not be affecting your AFR even if you have heat soak on the sensor.
BUT, check a log and see if your MAT is high at restart, or not.
Last edited by DNMakinson; 02-20-2017 at 04:10 PM.
Reason: Added last sentence.
Okay so who can point out to me what's wrong with this picture? Just tuning the N/A sections now, haven't messed with it above 4k RPM because it's running out of room to change (this is me using VEAL). Obviously can't go above 110kpa line because I'm still n/a.
I'm not running out of injector duty cycle - seems to be something off with the required fuel calculation?
VE tables are all just a part of the pulse width calculations, keep adding numbers. Usually with the correct injector dead times I idle in the 30s and see a peak of 120s.
Looking at my final FF640 map from Acamas, I was seeing idle in the ~90s and a 99kpa row of 110-115. With a 43psi system, 125 is probably about right. Boosted cells were in the 150-160 range at 200kpa.
By running out of room I mean the limit is set to 125 for VE. I suppose practically speaking I can raise that, but does anyone here think that a stock-head stock-cam Miata is at 125% volumetric efficiency? I know some of the better n/a Honda engines can break 100 but I'm only making 150whp so obviously that's false. Any hypotheses?
Here's my deadtime table - Andrew I copied it from the map you sent me that I'm guessing had 615's in it. Are they the same? FF's website doesn't have the deadtimes as a % of voltage and I was too lazy to punch all the number into excel..
Incorporate AFRTarget
Including the AFR target in speed density mode allows the VE table to be a “real” VE table and the desired AFR
to be specified in the AFR table.
With AFR not included, the AFR table is for reference only and the VE table takes full control.
I suppose it's just disabled by default for simplicity?
I suppose it's just disabled by default for simplicity?
I believe "Include AFR target" was a feature implemented a few years ago, so I would guess they didn't want to make it default for when people port old VE maps to new ones. It's certainly nice to have it on. Then you can test different AFR's without adjusting the VE map.
02-15-2017, 08:56 PM
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Yes, in the past, turbocharged Miatas have not been the most reliable things out there. I set out to change that with my turbo kit, calling on a decade of experience with turbocharged Miatas of all shapes and sizes. If you start with quality components designed by someone with a decade of experience building race-grade turbocharged Miatas, you may discover that the end result is substantially more reliable than your average steel-stud cast-iron turbo setup. 
