gemellocattivo.com

Which means "Evil Twin". Lets see your projects where you change boring into fun or create the fun from scratch.
It is currently Thu Sep 18, 2025 11:27 pm

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 1670 posts ]  Go to page Previous  1 ... 134, 135, 136, 137, 138, 139, 140 ... 167  Next
Author Message
PostPosted: Sat Feb 25, 2017 4:00 pm 
Offline
User avatar

Joined: Fri Jan 02, 2015 1:12 pm
Posts: 172
Hurry man, mulch season is coming. ;)


Top
 Profile Send private message  
 
PostPosted: Sat Feb 25, 2017 6:30 pm 
Offline

Joined: Thu Jan 01, 2015 6:47 pm
Posts: 4687
Pizzaman wrote:
Hurry man, mulch season is coming. ;)


I know...but the fire made the Honey-do list pretty long!


Top
 Profile Send private message  
 
PostPosted: Sat Feb 25, 2017 6:37 pm 
Offline

Joined: Thu Jan 01, 2015 6:47 pm
Posts: 4687
Madhatter wrote:

Raw cold start is always a PITA, always! Normally I run them at first start around 2500~3000 rpm it's a lot easier to maintain and is less stress on the cams, etc.. Once warm then like you said. This last 4L build was done on the dyno, the dyno operator uses a heated water tank, so the coolant is already nice and warm and we cycled it thru for a good hr before start-up that really sped things up.


This one seems particularly bad. While painting and installing pot lights and such today it occurred to me that injector timing might be part of the problem. I have it set to spray on the closed valve but I'm thinking that is just making it puddle on the stone cold valve and nothing is vaporizing so I need lots and lots of fuel. I'm going to try spraying right at the end of the intake cycle so the fuel goes into the moving air and see it it helps any.


Top
 Profile Send private message  
 
PostPosted: Sat Feb 25, 2017 6:51 pm 
Offline

Joined: Wed Jan 14, 2015 1:27 am
Posts: 166
mk e wrote:
Madhatter wrote:

Raw cold start is always a PITA, always! Normally I run them at first start around 2500~3000 rpm it's a lot easier to maintain and is less stress on the cams, etc.. Once warm then like you said. This last 4L build was done on the dyno, the dyno operator uses a heated water tank, so the coolant is already nice and warm and we cycled it thru for a good hr before start-up that really sped things up.


This one seems particularly bad. While painting and installing pot lights and such today it occurred to me that injector timing might be part of the problem. I have it set to spray on the closed valve but I'm thinking that is just making it puddle on the stone cold valve and nothing is vaporizing so I need lots and lots of fuel. I'm going to try spraying right at the end of the intake cycle so the fuel goes into the moving air and see it it helps any.


The ECU's I've been using have injector phasing for such a thing, it does help with idle and low RPM, beyond ~3k rpm it's effect is not noticeable. How much charge air is lost on overlap? If my memory serves right you're cam profile is very close to our 4L. I'll dig up the fuel table for idle and start and share the details if that helps.


Top
 Profile Send private message  
 
PostPosted: Sat Feb 25, 2017 7:20 pm 
Offline

Joined: Wed Jan 14, 2015 1:27 am
Posts: 166
screen shots, maybe something useful, if not no biggie.


Attachments:
Screenshot 2017-02-25 15.18.17.jpg
Screenshot 2017-02-25 15.18.17.jpg [ 629.62 KiB | Viewed 11736 times ]
Screenshot 2017-02-25 14.52.20.jpg
Screenshot 2017-02-25 14.52.20.jpg [ 804.73 KiB | Viewed 11736 times ]
Top
 Profile Send private message  
 
PostPosted: Sun Feb 26, 2017 8:22 am 
Offline

Joined: Thu Jan 01, 2015 6:47 pm
Posts: 4687
It does help Scott, thanks.

My crank enrich is at 350%....which is not much more than yours and my guess at VE was 50% where is looks like you're at 65-70 so really I have almost exactly the same fuel flow for starting. My tables are a bit different....I currently have a dedicated cranking anything, but do have cranking RPM in the VE and spark and I have a CLT vs cycle count table that primes and enriches during cranking/post start....at least in theory because I haven't turned it on yet. and I can add anything that seems like it might be helpful

My injector angles are at 360 for everything at the moment as that is the standard starting point but with my huge injectors and 240 (@0.050) cams I'm pretty sure means I'm spraying in the open intake and right out the still open exhaust. I was pondering trying up around 400-500 to know the fuel is going into the cylinder.

A lot of things to play with.......


Top
 Profile Send private message  
 
PostPosted: Mon Feb 27, 2017 11:17 am 
Offline

Joined: Thu Jan 01, 2015 6:47 pm
Posts: 4687
I made some minor changes to the ECU model to make it a bit easier to use and changed a bunch of settings to start using the start_enrich feature so now it should be able to deliver the fuel need during cranking then pull it back quickly to to run numbers. It should be warm again Tues/Wed and I have 48 new spark plugs waiting...hopefully I'll get some time to try it.

Here's what I"m going with for the next attempt for anyone interested....based on Scott's numbers and what I learned on the initial attempts.


Attachments:
tune screenshot 2017_02_27.JPG
tune screenshot 2017_02_27.JPG [ 398.53 KiB | Viewed 11677 times ]
Top
 Profile Send private message  
 
PostPosted: Tue Feb 28, 2017 6:49 pm 
Offline

Joined: Wed Jan 14, 2015 1:27 am
Posts: 166
What's your fuel pressure? The injectors I'm using for the 4L build run at ~70psi Made a BIG difference in idle etc.. A lot of the newer slim body molded injectors run at much higher pressures, or they dribble a fair amount, poor atomization etc..


Top
 Profile Send private message  
 
PostPosted: Tue Feb 28, 2017 9:51 pm 
Offline

Joined: Thu Jan 01, 2015 6:47 pm
Posts: 4687
Madhatter wrote:
What's your fuel pressure? The injectors I'm using for the 4L build run at ~70psi Made a BIG difference in idle etc.. A lot of the newer slim body molded injectors run at much higher pressures, or they dribble a fair amount, poor atomization etc..


Funny you should ask. Its set to 58 and it used to be 58 but it was more like 10 today.....I think its out of gas....I hope its out of gas because it its not then the pump is bad of the filter plugged. it would come 58 with the pump on for 15-30 seconds with the engine not cranking....I think its out of gas.

The injectors are ID1000 which are a modified bosch injector that want 3-5 bar. I'm not sure the pump is big enough to flow enough at much over 4 bar. I guess it doesn't really matter though because its pressure corrected

Something else is weird too....9 gas fouled plug all about the same and 3 white plugs. Its waste spark so if 10-12 have a signal from the ECU then 7-9 really should too. I wired both the coil and injector power in 3s so that's probably where I need to look....but I don't understand how I saw a rich O2 reading if 1/2 the cylinders weren't firing....that confuses me. I'll check everything before trying again.


Top
 Profile Send private message  
 
PostPosted: Tue Feb 28, 2017 10:55 pm 
Offline

Joined: Wed Jan 14, 2015 1:27 am
Posts: 166
mk e wrote:
Madhatter wrote:
What's your fuel pressure? The injectors I'm using for the 4L build run at ~70psi Made a BIG difference in idle etc.. A lot of the newer slim body molded injectors run at much higher pressures, or they dribble a fair amount, poor atomization etc..


Funny you should ask. Its set to 58 and it used to be 58 but it was more like 10 today.....I think its out of gas....I hope its out of gas because it its not then the pump is bad of the filter plugged. it would come 58 with the pump on for 15-30 seconds with the engine not cranking....I think its out of gas.

The injectors are ID1000 which are a modified bosch injector that want 3-5 bar. I'm not sure the pump is big enough to flow enough at much over 4 bar. I guess it doesn't really matter though because its pressure corrected

Something else is weird too....9 gas fouled plug all about the same and 3 white plugs. Its waste spark so if 10-12 have a signal from the ECU then 7-9 really should too. I wired both the coil and injector power in 3s so that's probably where I need to look....but I don't understand how I saw a rich O2 reading if 1/2 the cylinders weren't firing....that confuses me. I'll check everything before trying again.


Yeah, you'll want to get a proper fuel pump/ lines filters etc.. if you don't already have one. Check out Kinsler for reference. https://www.kinsler.com/

Current draw on waste spark for 12 coils is going to be LARGE! Have you mapped that out?
O2 sensors are finicky and don't like raw fuel fouling. I assume you're using heated O2's and you have them calibrated in air and pre-heated before cranking? O2 sensor function is fascinating and though boring to most it's helpful to know how they operate so that it helps in trouble shooting problems.
https://en.wikipedia.org/wiki/Oxygen_sensor
Since O2 sensors use external reference to air the ends should never be covered or sleeved and sealed, or in the case of the unisversal ones with flying leads the wires should not be soldered as that will block the reference air as they use the wire.


Top
 Profile Send private message  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 1670 posts ]  Go to page Previous  1 ... 134, 135, 136, 137, 138, 139, 140 ... 167  Next

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 7 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB® Forum Software © phpBB Group