MEGAsquirt A place to collectively sort out this megasquirt gizmo

0 PW tuning

Thread Tools
 
Search this Thread
 
Old 01-25-2021, 05:49 PM
  #1  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,207
Total Cats: 1,139
Default 0 PW tuning

Trying out Miata TBI on a FFS supercharger. After years of tuning, this is a first.

curly is online now  
Old 01-25-2021, 07:17 PM
  #2  
Tweaking Enginerd
iTrader: (2)
 
Ted75zcar's Avatar
 
Join Date: Mar 2013
Location: Boulder, CO
Posts: 1,778
Total Cats: 359
Default

Are you using staged injection?
Ted75zcar is offline  
Old 01-25-2021, 07:20 PM
  #3  
VladiTuned
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 35,821
Total Cats: 3,481
Default

So it's just as stupid now as it was decades ago? Can't say I'm surprised
18psi is offline  
Old 01-25-2021, 08:06 PM
  #4  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,207
Total Cats: 1,139
Default

Originally Posted by Ted75zcar
Are you using staged injection?
No, since staged injection would require me to wire 2-4 outputs all to one injector, or else it would only fire 1/4 time I'd want it to, ain't nobody got time for that. Although if this doesn't work out I'll find some time.

Originally Posted by 18psi
So it's just as stupid now as it was decades ago? Can't say I'm surprised
Yes. I think I'll tune the FF630s without any 5th injector, then add it in to see how well it cools AITs (GM sensor installed in plenum, and adjust from there. It's something like a 2000cc injector, so right now my range is 35-37% DC between too much and no difference. I'm guessing my frequency is the cause of this.
curly is online now  
Old 01-25-2021, 08:48 PM
  #5  
Tweaking Enginerd
iTrader: (2)
 
Ted75zcar's Avatar
 
Join Date: Mar 2013
Location: Boulder, CO
Posts: 1,778
Total Cats: 359
Default

So it runs at a fixed dutycycle? Would one of the generic PWMs work? I wouldn't imagine that it needs to be timed with the intake event.
Ted75zcar is offline  
Old 01-25-2021, 08:56 PM
  #6  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,207
Total Cats: 1,139
Default

I'm using the 3d boost duty table, so fixed for any given rpm/throttle. Generic PWM would be the same, although it would allow me to change the load axis. Doesn't need to be timed to intake event, it'll explode when the valves are closed and the plug fires. Good enough for GM, good enough for me.
curly is online now  
Old 01-25-2021, 09:06 PM
  #7  
Tweaking Enginerd
iTrader: (2)
 
Ted75zcar's Avatar
 
Join Date: Mar 2013
Location: Boulder, CO
Posts: 1,778
Total Cats: 359
Default

I certainly wouldn't want to give up a boost table, we are already 1 short AFAIAC. Not being able to do a proper boost by gear and flex blend at the same time is a PITA.

GL man!
Ted75zcar is offline  
Old 01-25-2021, 10:02 PM
  #8  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,207
Total Cats: 1,139
Default

Car is not/will not be using flex fuel, nor can I control boost AFAIK (SC), and it'll make 180, maybe 200whp (I'll post a dyno sheet eventually), so boost by gear...not necessary.
curly is online now  
Old 01-25-2021, 10:32 PM
  #9  
Tweaking Enginerd
iTrader: (2)
 
Ted75zcar's Avatar
 
Join Date: Mar 2013
Location: Boulder, CO
Posts: 1,778
Total Cats: 359
Default

I have an SC and control boost
Ted75zcar is offline  
Old 01-26-2021, 09:54 AM
  #10  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,207
Total Cats: 1,139
Default

Slightly different setup
curly is online now  
Old 01-28-2021, 04:16 PM
  #11  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,207
Total Cats: 1,139
Default

Just returned from the dyno, made 188hp with MATs hitting ~200 by redline. The “e-cool” injector did nothing for boost or power or MATs, and was disabled. The biggest help was making a non-corrugated intake tube, which made 17 extra ponies.



we did try every variant of filter/no filter, maf/no maf, tube/no tube, and it was definitely the tube destroying all flow.
curly is online now  
Old 01-28-2021, 09:07 PM
  #12  
Tweaking Enginerd
iTrader: (2)
 
Ted75zcar's Avatar
 
Join Date: Mar 2013
Location: Boulder, CO
Posts: 1,778
Total Cats: 359
Default

So ecool did nothing for MAT? This is a belief I have had for ages but have never had (or looked) for data to support. Thanks for the update!
Ted75zcar is offline  
Old 01-28-2021, 10:12 PM
  #13  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,207
Total Cats: 1,139
Default

I’ll post some logs, but as far as I could see, no it did nothing. I tuned it for 11.2-11.6 from 1500-7400rpm. With flow force’s 650s, they performed beautifully. Every pull would go from mid 140s to high 190s MAT. Added enough 5th injector so the entire AFR curve was .5-.75 points richer, even after taking 10% fuel out of the port injection. MATs we’re still going 140s to 190s. I could have continued to add more, but wasn’t interested in actually turning it into a TBI car. This is also 40s ambient, i shudder to think what it’d do on hot summer day. It’s really quick to recover with cold air blowing on it now.

its not my cup of tea, hence my thousands of posts on MT.net and not MSC.net, but it’s still fun, especially lower RPM. More torque than a turbo briefly until it turns more into a rotrex power band feeling. But my biggest complaint is that intake. I’m more disappointed it’s sold with that then the 5th injector black magic.
curly is online now  
Old 01-29-2021, 05:11 AM
  #14  
Senior Member
 
der_vierte's Avatar
 
Join Date: Mar 2017
Location: GER
Posts: 763
Total Cats: 113
Default

Curly, would you share the dyno plot, please ?
der_vierte is offline  
Old 01-29-2021, 09:11 AM
  #15  
Tweaking Enginerd
iTrader: (2)
 
Ted75zcar's Avatar
 
Join Date: Mar 2013
Location: Boulder, CO
Posts: 1,778
Total Cats: 359
Default

Yes, superchargers definitely have their advantages, but don't tell anybody around here... they might get upset. The PD SC is actually making quite a comeback, especially in the UK.

Seriously though, nobody who buys and installs one of these kits actually uses that tube do they? Even the most nooby-noob-newbaru should be able to look at that thing and know it is rubbish. It looks like what I use on my downspouts.
Ted75zcar is offline  
Old 01-29-2021, 11:59 AM
  #16  
Senior Member
iTrader: (1)
 
dleavitt's Avatar
 
Join Date: May 2015
Location: Salem, OR
Posts: 757
Total Cats: 223
Default

Originally Posted by Ted75zcar
Yes, superchargers definitely have their advantages, but don't tell anybody around here... they might get upset. The PD SC is actually making quite a comeback, especially in the UK.

Seriously though, nobody who buys and installs one of these kits actually uses that tube do they? Even the most nooby-noob-newbaru should be able to look at that thing and know it is rubbish. It looks like what I use on my downspouts.
You obviously haven't interacted with the kind of people that buy FFS supercharger kits.
dleavitt is offline  
Old 01-29-2021, 12:02 PM
  #17  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,207
Total Cats: 1,139
Default

Here's snap shots of the datalogs for now, I'll have the dyno plots soon. First is with E-cool providing around 10-15% of the fueling for the car. MAT starts at 142, climbs to 183 by redline, 190 max before beginning to drop off after the run



Next is a run soon after, I basically waited a minute or two until MATs were back down to the 140s. MAT starts at 142, and hit 187 by redline, nearly 195 before cooling back off. Yes, that's roughly a 4 degree increase, however that 2% difference was not significant enough to warrant continued tuning on the 5th injector. MATs are still wildly out of control, and require significant changes in intake cooling, not a 5th injector.




curly is online now  
Old 01-29-2021, 12:07 PM
  #18  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,207
Total Cats: 1,139
Default

In contrast, here is another car I dyno'd recently. BP4W EFR 6278, making 260hp. MATs climbed from barely above ambient to a peak of 113, 4 minutes after the previous run. This was the 22nd redline pull of the day, which took an hour.

The two supercharged datalogs I posted above, were the 11th and 12th pull of the day, and taken 5 minutes apart.

curly is online now  
Old 01-29-2021, 01:54 PM
  #19  
Retired Mech Design Engr
iTrader: (3)
 
DNMakinson's Avatar
 
Join Date: Jan 2013
Location: Seneca, SC
Posts: 5,009
Total Cats: 857
Default

What was the Ambient on the EFR run? Stated another way, what the the total rise over Ambient at 260 WHP?

I think the low MAT reading is about 55F, but I find it hard to read. That would mean about 60*F Rise in a virtual steady state condition?
DNMakinson is offline  
Old 01-29-2021, 03:29 PM
  #20  
Cpt. Slow
Thread Starter
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 14,207
Total Cats: 1,139
Default

Ambient for the EFR car was probably 40-50. Yes, low MAT was 55. AIT is in the intercooler end tank IIRC, don’t recall if it was a decent intercooler or not.
curly is online now  


Quick Reply: 0 PW tuning



All times are GMT -4. The time now is 03:51 PM.