cold start FTL - Page 3 - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


MEGAsquirt A place to collectively sort out this megasquirt gizmo

Reply
 
 
 
LinkBack Thread Tools
Old 10-17-2007, 11:57 AM   #41
Supporting Vendor
iTrader: (5)
 
Join Date: Jun 2006
Location: Duluth, GA 30097
Posts: 798
Total Cats: 0
Default

Quote:
Originally Posted by richyvrlimited View Post
that's the 1.8 browntops 1.6 bluetops are 205cc
That's what I had thought too originally, but I had based the 230cc off the FAQ... so I can do some digging, but which is it?

Here's the DIY Turbo FAQ entry on it:

Quote:
The 1.6L (230cc) fuel injectors have enough room to run about 5-6psi. However at this level, the fuel pressure required to get enough fuel into the motor through the small injectors becomes so great, that the injectors can actually lock. If you are running more than 140-150rwhp, chances are the injectors are maxed out. A very common upgrade is to install the 1.8L injectors. These will should provide you enough room to run about 7-9psi of boost (170-180rwhp).

94-97 (tan) 265cc - #195500-2180
99-00 (red) 240cc (pass on these) -#195500-4430
01-05 (Lt. purple) 265cc -#195500-4060
Taken from https://www.miataturbo.net/diy-turbo-discussion-14/diy-faq-all-your-answers-one-big-post-4288/
FoundSoul is offline   Reply With Quote
Old 10-17-2007, 12:01 PM   #42
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,892
Total Cats: 1,792
Default

those numbers have been verified from a number of sources.

now if jerry can only solve my issue.
Braineack is offline   Reply With Quote
Old 10-17-2007, 12:01 PM   #43
Senior Member
Thread Starter
iTrader: (2)
 
Join Date: Mar 2006
Location: MA
Posts: 885
Total Cats: 2
Default

Quote:
Originally Posted by Braineack View Post
yeah, i dunno what the deal is now. even without heat soak it wont restart without tons of effort.

this morning i stopped by Rosenthal, intake temps of 50 coolant at 190. stopped for about 3 minutes and came back out. Tried to crank it and no go, all temps about the same as when I left it. :(

have you noticed much of a difference with MAT only, CLT only, or averaged?

seems to me that if your intake temps are 50, and the coolant is 190, averaging them would put you in a spot where nobody's happy... i'm just supposing, though.
devin mac is offline   Reply With Quote
Old 10-17-2007, 12:02 PM   #44
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,892
Total Cats: 1,792
Default

no its clt only, i think i want to try averaging them.
Braineack is offline   Reply With Quote
Old 10-17-2007, 12:04 PM   #45
Senior Member
Thread Starter
iTrader: (2)
 
Join Date: Mar 2006
Location: MA
Posts: 885
Total Cats: 2
Default

yeah, i was thinking about that the other day, when mentioned that i fired the car up with 43* CLT and 60* intake, but then later couldn't fire it with similar CLT and 40* intake.
devin mac is offline   Reply With Quote
Old 10-17-2007, 12:27 PM   #46
Elite Member
iTrader: (1)
 
Join Date: Jun 2006
Location: Warrington/Birmingham
Posts: 2,658
Total Cats: 39
Default

Quote:
Originally Posted by FoundSoul View Post
That's what I had thought too originally, but I had based the 230cc off the FAQ... so I can do some digging, but which is it?

Here's the DIY Turbo FAQ entry on it:



Taken from https://www.miataturbo.net/showthread.php?t=4288

i've read that FAQ a lot and never noticed it quoted different numbers than what I'm used to.... hrm

ah well always happy to be proved wrong
richyvrlimited is offline   Reply With Quote
Old 10-17-2007, 12:28 PM   #47
Supporting Vendor
iTrader: (5)
 
Join Date: Jun 2006
Location: Duluth, GA 30097
Posts: 798
Total Cats: 0
Default

Quote:
Originally Posted by Braineack View Post
those numbers have been verified from a number of sources.

now if jerry can only solve my issue.
Don't know if I can magically solve anything-- but I'll surely try and help

Firstly I don't know that i'd average IAT and CLT for this-- the engine temp is much more critical for this calculation. If you're averaging the two, and IAT is at 50 while CLT is at 190, you need a tiny little PW to start the car, but you're getting a much bigger one because the averaged in IAT reading in bringing the temp used to calculate cranking PW way down to a much lower temp, where a much higher PW is commanded, instantly soaking your plugs and flooding you out.

That would be my theory anyways...
FoundSoul is offline   Reply With Quote
Old 10-17-2007, 12:33 PM   #48
Supporting Vendor
iTrader: (5)
 
Join Date: Jun 2006
Location: Duluth, GA 30097
Posts: 798
Total Cats: 0
Default

Quote:
Originally Posted by richyvrlimited View Post
i've read that FAQ a lot and never noticed it quoted different numbers than what I'm used to.... hrm

ah well always happy to be proved wrong
Me too-- much better to be proved wrong, learn something from it and be better off the next time than hardheaded about it and dumb forever right?

I had always used the 205cc value before on the 1.6 and 230cc on the 1.8, probably just forum misinformation which is all too common, and manufacturers really don't make this type of info the easiest to come by alot of the time. This is actually part (not all) of the reason why the AFR number used to set REQ_FUEL when scaling to different injector sizes on the MSPNP MM9093 and MM9495 isn't 14.7-- I had to account after the fact for the true injector sizes so it would scale properly for you guys. It won't change anything though as long as it's consistent.
FoundSoul is offline   Reply With Quote
Old 10-17-2007, 12:47 PM   #49
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,892
Total Cats: 1,792
Default

i guess ill try lowering the PWs a tad more and turning off the priming pulses.
Braineack is offline   Reply With Quote
Old 10-17-2007, 07:33 PM   #50
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,892
Total Cats: 1,792
Default

that seemed to have worked. i drove home and parked and waited untill 100* playing with my ait based corrections and PWs some more got it to start everytime from 80* to 108*

hopefully it will do the same tomorrow at 190* CLT and 50* intake.
Braineack is offline   Reply With Quote
Old 10-17-2007, 07:40 PM   #51
Elite Member
iTrader: (5)
 
Atlanta93LE's Avatar
 
Join Date: Sep 2006
Location: Marietta, GA
Posts: 2,198
Total Cats: 1
Default

So...what 1.6L injector size did you use to rescale the diyautotune cold start pw values?
Atlanta93LE is offline   Reply With Quote
Old 10-17-2007, 08:08 PM   #52
Supporting Vendor
iTrader: (5)
 
Join Date: Jun 2006
Location: Duluth, GA 30097
Posts: 798
Total Cats: 0
Default

Quote:
Originally Posted by Atlanta93LE View Post
So...what 1.6L injector size did you use to rescale the diyautotune cold start pw values?
Actual injector sizes will apply for this as it was tuned with the actual factory injectors in the car, so 230cc for the 90-93, and 265cc for the 94-95.
FoundSoul is offline   Reply With Quote
Old 10-17-2007, 08:09 PM   #53
Supporting Vendor
iTrader: (5)
 
Join Date: Jun 2006
Location: Duluth, GA 30097
Posts: 798
Total Cats: 0
Default

Glad to hear it looks like you've made some progress Scott--
FoundSoul is offline   Reply With Quote
Old 10-17-2007, 08:39 PM   #54
Elite Member
iTrader: (5)
 
Atlanta93LE's Avatar
 
Join Date: Sep 2006
Location: Marietta, GA
Posts: 2,198
Total Cats: 1
Default

Quote:
Originally Posted by FoundSoul View Post
Actual injector sizes will apply for this as it was tuned with the actual factory injectors in the car, so 230cc for the 90-93, and 265cc for the 94-95.
Thanks very much! Exactly the info I was looking for.
Atlanta93LE is offline   Reply With Quote
Old 10-17-2007, 10:00 PM   #55
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,892
Total Cats: 1,792
Default

they also use 13.7 as the afr multipler, however, iirc.
Braineack is offline   Reply With Quote
Old 10-17-2007, 10:09 PM   #56
Elite Member
iTrader: (13)
 
cjernigan's Avatar
 
Join Date: Oct 2006
Location: Atlanta, GA
Posts: 8,147
Total Cats: 6
Default

Anyone know why DIYs cranking/prime table counts down until it reaches 40F then it jumps up again and then continues counting down versus counting down the entire time?
This might just be an error of me not having MT setup to read their MSQ but I don't think that the values themselves would change because of that.

Jerry, what kind of AIT related air density have you used on turbo cars? Just curious if you have a table to share.
cjernigan is offline   Reply With Quote
Old 10-17-2007, 10:39 PM   #57
Elite Member
iTrader: (12)
 
Join Date: Aug 2006
Location: Central-ish VA
Posts: 4,449
Total Cats: 16
Default

It never got below 40* in Atlanta, so they couldn't tune below that.
neogenesis2004 is offline   Reply With Quote
Old 10-17-2007, 11:58 PM   #58
Senior Member
Thread Starter
iTrader: (2)
 
Join Date: Mar 2006
Location: MA
Posts: 885
Total Cats: 2
Default

i ended up cutting the DIY cranking values down, by multiplying them by 75%, and so far so good. only tested in 50* temps so far, though. tomorrow morning i should get a solid 40* startup try, so i'll see how it works tomorrow morning. optimistic, though.
devin mac is offline   Reply With Quote
Old 10-18-2007, 12:05 AM   #59
Elite Member
iTrader: (13)
 
cjernigan's Avatar
 
Join Date: Oct 2006
Location: Atlanta, GA
Posts: 8,147
Total Cats: 6
Default

Quote:
Originally Posted by neogenesis2004 View Post
It never got below 40* in Atlanta, so they couldn't tune below that.
hahahhaha That's right, makes sense, i didn't think about that.
cjernigan is offline   Reply With Quote
Old 10-18-2007, 12:10 AM   #60
Senior Member
Thread Starter
iTrader: (2)
 
Join Date: Mar 2006
Location: MA
Posts: 885
Total Cats: 2
Default

heh, i had the same thought as you, cj. then the "oh yeah... atlanta... 40deg..." thought hit me, too.
devin mac is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 59 Yesterday 09:00 PM
Expected intake temps on the track? tazswing Race Prep 20 10-03-2015 12:04 PM
Time to start learning and play with tuning The Gleas MEGAsquirt 3 10-01-2015 10:30 AM
Leaky Wilwoods mx592 Suspension, Brakes, Drivetrain 1 10-01-2015 01:45 AM
Low oil pressure after 1.8 swap and new turbo setup JesseTheNoob DIY Turbo Discussion 15 09-30-2015 03:44 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 07:22 AM.