MegaSquirt up and running in ZAngel's car
05-04-2005, 10:37 PM
#1
TECH Senior Member
Thread Starter
iTrader: (7)
Join Date: Jan 2002
Location: Katy, TX
Posts: 12,754
Likes: 0
Received 0 Likes
on
0 Posts
MegaSquirt up and running in ZAngel's car Did some preliminary "checking" on everything on the car tonight, and decided "why not" fire it up? 
This is nearly a 100% new combination -- only the longblock remained the same since the last time this car was running. New camshaft, added a turbocharger, new injectors, added the MS, etc.
Anyway - I did all the initial setup on the MS in the house with the "stimulator" board, and went out and did nothing more than plug the MegaSquirt into the harness and twist the key. The car fired up on the first shot, and idled down perfectly. To say the least, I'm VERY impressed with the MegaSquirt and how fast and easy it was to get it to this point. The car is still up in the air on jackstands, as there's a few things left to tidy up (mainly tying down some wiring and braided lines, and little things like putting beauty panels back on). Once those things are done, its the on-the-road phase.
This is nearly a 100% new combination -- only the longblock remained the same since the last time this car was running. New camshaft, added a turbocharger, new injectors, added the MS, etc. Anyway - I did all the initial setup on the MS in the house with the "stimulator" board, and went out and did nothing more than plug the MegaSquirt into the harness and twist the key. The car fired up on the first shot, and idled down perfectly. To say the least, I'm VERY impressed with the MegaSquirt and how fast and easy it was to get it to this point. The car is still up in the air on jackstands, as there's a few things left to tidy up (mainly tying down some wiring and braided lines, and little things like putting beauty panels back on). Once those things are done, its the on-the-road phase.
05-05-2005, 06:49 AM
#5
TECH Senior Member
Thread Starter
iTrader: (7)
Join Date: Jan 2002
Location: Katy, TX
Posts: 12,754
Likes: 0
Received 0 Likes
on
0 Posts
Yup, Hawk is right.. The MS unit mounts inside the car, since it is not in a weatherproof enclosure, nor are they using "automotive grade" components. I found a nice pocket in the dashboard that fits the MS perfectly, between the radio and the passenger air bag. Its also convenient to hook up the MAP sensor inside the MS box -- the A/C controls are directly below this location, and as many of you know a vacuum line runs directly from the intake to the A/C controls.
A wiring harness (custom built) runs from the MS through the factory grommet in the firewall behind the PCM. From there it branches out into all of its sensors:
Power -> ran a dedicated feed to the ignition relay in the drivers side underhood electrical center
Ground -> grounded at the body lug by the battery
TPS -> spliced at the PCM
Tach signal -> spliced at the PCM
Intake air temp -> dedicated sensor, mounted in front of the MAF. Same as factory LS1 sensor.
Coolant temp -> dedicated sensor, mounted in the passenger side head (same hole as used on the driver's side, using an additional factory sensor)
Fuel injectors -> built a new harness, because I didn't want to chop up the factory harness. This simply lays over the motor identically to the factory harness, and splices back into the MS harness by the PCM. If something goes wrong with the MS, we can simply unplug the injectors from the MS and plug back in the factory connectors and drive away.
That's IT !! Nothing more to it, since the MS is running in fuel-only mode. I'm thinking after a while I'll build another MS unit, and hack up the code to fire the individual coils and see how it does with ignition duty
A wiring harness (custom built) runs from the MS through the factory grommet in the firewall behind the PCM. From there it branches out into all of its sensors:
Power -> ran a dedicated feed to the ignition relay in the drivers side underhood electrical center
Ground -> grounded at the body lug by the battery
TPS -> spliced at the PCM
Tach signal -> spliced at the PCM
Intake air temp -> dedicated sensor, mounted in front of the MAF. Same as factory LS1 sensor.
Coolant temp -> dedicated sensor, mounted in the passenger side head (same hole as used on the driver's side, using an additional factory sensor)
Fuel injectors -> built a new harness, because I didn't want to chop up the factory harness. This simply lays over the motor identically to the factory harness, and splices back into the MS harness by the PCM. If something goes wrong with the MS, we can simply unplug the injectors from the MS and plug back in the factory connectors and drive away.
That's IT !! Nothing more to it, since the MS is running in fuel-only mode. I'm thinking after a while I'll build another MS unit, and hack up the code to fire the individual coils and see how it does with ignition duty
05-05-2005, 08:20 AM
#7
Originally Posted by Brains
Coolant temp -> dedicated sensor, mounted in the passenger side head (same hole as used on the driver's side, using an additional factory sensor)
exactly what temp sensor did you use? 98 temp sensor?
do you have the resistance-> temp table for that sensor?
Trending Topics
05-05-2005, 08:41 AM
#8
On The Tree
Join Date: Jan 2004
Location: Omaha, NE
Posts: 133
Likes: 0
Received 0 Likes
on
0 Posts
Brains - saw your post this morning on MS-EFI.com, and wanted to say congratulations. Starting on the very first try, with *any* standalone EMS, is like hitting a hole-in-one on your first golf outing...
I am anxious for tuning and performance updates - please keep us all posted!
-scott
I am anxious for tuning and performance updates - please keep us all posted!
-scott
05-05-2005, 10:24 AM
#9
TECH Senior Member
Thread Starter
iTrader: (7)
Join Date: Jan 2002
Location: Katy, TX
Posts: 12,754
Likes: 0
Received 0 Likes
on
0 Posts
Ryan: Haven't checked, an in fact didn't even think about it. I sure will check now though 
If I have to, running a dedicated line won't be too tough either.
Dude: Yes, we used a 98 sensor. Half of it is going unused, and all I did was hook up a pair of wires at a time until the temp read correctly on the MS
At first glance, it looks to be already calibrated -- the sensor read 74 degrees when it was in the mid 70's last night.. lol.. MS is "calibrated" to GM sensors, so it should be good.
Diesel: well, its not 100% standalone Its just fuel, right? hehehe.. I'm kinda anxious to get further into it though, and maybe someday hand over boost control and whatnot to the MS. I'll be happy with fuel, wideband, etc. for now though.
If I have to, running a dedicated line won't be too tough either.Dude: Yes, we used a 98 sensor. Half of it is going unused, and all I did was hook up a pair of wires at a time until the temp read correctly on the MS
At first glance, it looks to be already calibrated -- the sensor read 74 degrees when it was in the mid 70's last night.. lol.. MS is "calibrated" to GM sensors, so it should be good.Diesel: well, its not 100% standalone
Its just fuel, right? hehehe.. I'm kinda anxious to get further into it though, and maybe someday hand over boost control and whatnot to the MS. I'll be happy with fuel, wideband, etc. for now though.
05-05-2005, 10:35 AM
#10
Originally Posted by Brains
Dude: Yes, we used a 98 sensor. Half of it is going unused, and all I did was hook up a pair of wires at a time until the temp read correctly on the MS At first glance, it looks to be already calibrated -- the sensor read 74 degrees when it was in the mid 70's last night.. lol.. MS is "calibrated" to GM sensors, so it should be good.
At first glance, it looks to be already calibrated -- the sensor read 74 degrees when it was in the mid 70's last night.. lol.. MS is "calibrated" to GM sensors, so it should be good.btw, when you say half of it is going unused, what do you mean?
05-05-2005, 10:42 AM
#11
TECH Senior Member
Thread Starter
iTrader: (7)
Join Date: Jan 2002
Location: Katy, TX
Posts: 12,754
Likes: 0
Received 0 Likes
on
0 Posts
The 98 ECT sensor has two elements in it .. three pins.. I'll definitely compare the reading to the other sensor being read via the LS1 PCM, just to make sure its close..
05-05-2005, 01:55 PM
#13
TECH Senior Member
Thread Starter
iTrader: (7)
Join Date: Jan 2002
Location: Katy, TX
Posts: 12,754
Likes: 0
Received 0 Likes
on
0 Posts
The MAF is still there, for now. Since we're about to go on the HotRod Power Tour, I figured lets leave as much of the tune alone as we can Once we're back the MAF goes bye-bye.
Spark would be tuned the same w/o the MAF, its fueling that changes when you remove it -- which is now being run by the MegaSquirt. The only reason I left the MAF in there for now is to have a nice measure of air mass to compare against the speed/density calculations when tuning the MegaSquirt.
Once we're back the MAF goes bye-bye.Spark would be tuned the same w/o the MAF, its fueling that changes when you remove it -- which is now being run by the MegaSquirt. The only reason I left the MAF in there for now is to have a nice measure of air mass to compare against the speed/density calculations when tuning the MegaSquirt.
05-06-2005, 12:06 AM
#18
TECH Senior Member
Thread Starter
iTrader: (7)
Join Date: Jan 2002
Location: Katy, TX
Posts: 12,754
Likes: 0
Received 0 Likes
on
0 Posts
Yes, the Mega has ACT (air charge temp) correction, as well as coolant temp and manifold pressure. There is the option to run an additional pressure sensor for real-time altitude correction as well, with a simple code update.
For naturally aspirated motors with HUGE camshafts, you have the option to run in Alpha-N mode (RPM and throttle position based fueling) versus the "normal" speed density method.
For naturally aspirated motors with HUGE camshafts, you have the option to run in Alpha-N mode (RPM and throttle position based fueling) versus the "normal" speed density method.