Rx7 550cc Turbo Injectors Idling Problem - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


MSPNP MSPNP specific Megasquirt related discussion.

Reply
 
 
 
LinkBack Thread Tools
Old 12-05-2015, 01:05 PM   #1
Newb
Thread Starter
 
Join Date: Jun 2014
Posts: 3
Total Cats: 0
Default Rx7 550cc Turbo Injectors Idling Problem

I've got myself a set of Rx7 FC Turbo 550cc Injectors for my 1992 Mazda Eunos 1.6 Turbo.

Fitting them was straight forward and I adjusted the required fuel to a flow rate​ of 550cc which gave me a value of 4.9(2.45ms)

Driving the car was no problem, the map was pretty close to the 1.8 254cc injector map I had set up

However the Idle is extremely poor, it seems to idle for a second and stalls

Would adjusting my​​​ Injection Dead Timing to 1.2-1.5ms correct this and what has everyone else done to sort this problem out?

This is the photo of my screenshot

Attached Thumbnails
Rx7 550cc Turbo Injectors Idling Problem-80-rx7_20injectors_zps6dbdhor9_aa3d7e8432ae10d6697d7430e46df41483cb87af.jpg  
Ste_mx is offline   Reply With Quote
Old 12-05-2015, 02:04 PM   #2
Cpt. Slow
iTrader: (25)
 
curly's Avatar
 
Join Date: Oct 2005
Location: Oregon City, OR
Posts: 12,107
Total Cats: 518
Default

What's your idle afr? Increasing the dead time is just increasing the fuel amount and screwing the rest of your map up, and making tuning a headache.
curly is offline   Reply With Quote
Old 12-05-2015, 02:18 PM   #3
Newb
Thread Starter
 
Join Date: Jun 2014
Posts: 3
Total Cats: 0
Default

Its set to 14.7
Ste_mx is offline   Reply With Quote
Old 12-05-2015, 03:37 PM   #4
SADFab Destructive Testing Engineer
iTrader: (5)
 
aidandj's Avatar
 
Join Date: Apr 2014
Location: Beaverton, USA
Posts: 17,997
Total Cats: 1,463
Default

But what is it actually.
aidandj is offline   Reply With Quote
Old 12-05-2015, 04:03 PM   #5
Sadfab Union President
iTrader: (3)
 
Join Date: May 2014
Location: Kansas
Posts: 2,690
Total Cats: 113
Default

You aren't going to be able to idle those old slow injectors at 14.7 on 1.6 batch injection. Your calculated pulsewidths are probably smaller than your deadtime values near idle and therefore you aren't getting consistent fueling. Near 550cc injectors your idle PW is going to be near 2.0ms on sequential. If you run batch, you have two squirts per cycle, so you get two 1.0ms pulses which are lower than deadtime.

Drop down to 13.8 AFR or upgrade to sequential, or injectors of this century...
deezums is offline   Reply With Quote
Old 12-09-2015, 05:53 PM   #6
Moderator
iTrader: (11)
 
sixshooter's Avatar
 
Join Date: Nov 2008
Location: Tampa, Florida
Posts: 15,669
Total Cats: 1,561
Default

~1.2ms is where my rx7 440s were happy.
sixshooter is offline   Reply With Quote
Old 12-10-2015, 04:54 PM   #7
Senior Member
iTrader: (8)
 
nigelt's Avatar
 
Join Date: Sep 2014
Location: Carmel Valley, CA
Posts: 660
Total Cats: 71
Default

I ship world wide
nigelt is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
1992 Miata - Smiles Per Gallon AngelGdo Build Threads 13 07-05-2016 10:50 PM
Help! Ignition timing on MX5 Turbo, MS2PNP PendleMotorcycles MEGAsquirt 27 01-08-2016 06:58 PM
Fuel pump shuts off at low RPM ryansmoneypit MEGAsquirt 23 12-08-2015 10:29 AM
1.8 swapped, 180hp hardtop miata mxkite24 Cars for sale/trade 6 12-01-2015 11:14 AM
Does the 10AE front lip, side skirts, and rear spats fit 2001 bumpers? thumpetto007 General Miata Chat 4 11-30-2015 01:41 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 08:38 AM.