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falconfp2001
I just installed MegaSqurt 2 and I'd like a comparable base VE table to compare with what I've generated.

I have a stock 1.7 with MegaSquirt 2 Extra

running fuel only at the moment

Thanks
kwlane
I have a stock 1.7 engine that I plan to convert back to FI so really interested in how the megasquirt install worked out and any info that might help get it started and to get it tuned. Did you set up the ECU for fuel only?
falconfp2001
QUOTE(kwlane @ Apr 12 2012, 09:48 PM) *

I have a stock 1.7 engine that I plan to convert back to FI so really interested in how the megasquirt install worked out and any info that might help get it started and to get it tuned. Did you set up the ECU for fuel only?


It went well and yes, I am running fuel only right now but I plan on adding EDIS. The only thing that I'm having problems with right now is the O2 sensor and gauge but you can actually run on just MAP if you have a decent VE table generated. It's not recommended but it can be done.

I took a more non traditional route. I used a 2.0L intake on my 1.7L engine. mainly because I had an Idea for the IAT and it actually works really well that way. I have perfect idle speed no matter what temp.

If you want to do it on a budget and fuel only, you can get MS1 and run it with MS Extra firmware. If I were to do this again on a tighter budget, I'd do that and use all the stock intake, CHT, IAT, AAR and then just a narrow band O2. would only be 300 to 400 and it would still be better than the old injection system.
r_towle
Read Rich Wilners thread....he has a solution to the O2 sensor

Rich
rwilner
QUOTE(r_towle @ Apr 13 2012, 08:50 AM) *

Read Rich Wilners thread....he has a solution to the O2 sensor

Rich


Frank
The VE table won't do you any good without the rest of the MSQ. The VE table is built upon the other base parameters in the tuning file -- req_fuel (base fuel offset), injector flow rates, injector open time, etc etc -- and also your fuel system...what's your fuel pressure set to?

Really what you need to do is get your AFR meter reading correctly and tune your VE table based on what the O2 sensor is telling you, and then adjust the O2 targets based on CHTs and your "butt dyno." That's the only way to tune the car. It worked very well for me...I'm seeing CHTs around 300 deg F under #3 in 5th gear at 75 mph, this is with premium gas...on 89 I get up to around 325 during cruise.

If someone has a complete MSQ using the same fuel injectors and fuel pressure you're running, that could be a good starting point for you.
falconfp2001
QUOTE(rwilner @ Apr 13 2012, 08:04 AM) *

QUOTE(r_towle @ Apr 13 2012, 08:50 AM) *

Read Rich Wilners thread....he has a solution to the O2 sensor

Rich


Frank
The VE table won't do you any good without the rest of the MSQ. The VE table is built upon the other base parameters in the tuning file -- req_fuel (base fuel offset), injector flow rates, injector open time, etc etc -- and also your fuel system...what's your fuel pressure set to?

Really what you need to do is get your AFR meter reading correctly and tune your VE table based on what the O2 sensor is telling you, and then adjust the O2 targets based on CHTs and your "butt dyno." That's the only way to tune the car. It worked very well for me...I'm seeing CHTs around 300 deg F under #3 in 5th gear at 75 mph, this is with premium gas...on 89 I get up to around 325 during cruise.

If someone has a complete MSQ using the same fuel injectors and fuel pressure you're running, that could be a good starting point for you.


I'm using stock injectors and stock fuel pressure regulator set at stock pressure. I think someone on the forum was running fuel only on a stock 1.7 with all stock sensors and so I was hoping I could get a map to compare.

I have to replace the AFR Gauge again but my initial tune and autotune has given me a good starting point. It drives good and idles really good with the IAC setup I used.
rwilner
QUOTE(falconfp2001 @ Apr 13 2012, 11:18 AM) *

It drives good and idles really good with the IAC setup I used.


Frank
What IAC setup did you use?

I tuned mine without an idle control valve and drivability is good when it's cold, but I think it would be better with an IAC.
underthetire
I can send you one. All stock 1.7 stuff on a bus 2.0.
Changes- GM TPS
GM (bosch) narrow band heated o2
GM air temp sensor.

Its at home though.

Ran good then, IDK if it was totally correct.
falconfp2001
QUOTE(rwilner @ Apr 13 2012, 08:29 AM) *

QUOTE(falconfp2001 @ Apr 13 2012, 11:18 AM) *

It drives good and idles really good with the IAC setup I used.


Frank
What IAC setup did you use?

I tuned mine without an idle control valve and drivability is good when it's cold, but I think it would be better with an IAC.



I used the Wells AC320 (found on Ebay) got the pigtail from DIY and I made my own mount using the AAR inlet but you can use the billet adapter they have at DIY. If you use the regular Firmware, the steps go backwards 160 is closed and 0 is fully opened. If you upgrade to the Extra Firmware, it gives you a test mode for the Idle Stepper that will tell you how many steps till fully open and it reverses the steps, making it 160 fully open and 0 fully closed.

First you have to get the engine hot and then adjust your idle speed air valve on the TB to match what you want.Then you have to let it cool completely down before calibrating. You have to make sure your starting position is the fully open in Idle Control, then Set the IAC on always move. Then you have 4 temp settings for crank position. After cranking it will close to the current temp position and constantly decrease the opening until fully closed.

It gives you 10 definable temp settings for the IAC steps. I used

-40
0
40
80
100
150
200
250
300
350

as my temps. The stepper is constantly closing on a curve from each temp step to the next.

You have to start up the engine and then adjust these IAC steps live while the engine warms up until it is at its highest. By the time it is fully closed you should have the always idle speed you want. I did this twice to make sure and it is fully closed by 250 while idling. It went from step 75 to step 10. It will not be the same if you do not set it up the same.

The only problem I had at first was the seal on the pintle. It has to be a good tight seal so I had to rethink this install. I came up with taking a vacuum boot and using it as a cupped o-ring instead to seal the pintle. It looks clean but it was a hassle to make.

The idle speed is much more stable now but I can't wait until I get EDIS installed. On your system it would be perfect idle at all times.
falconfp2001
QUOTE(underthetire @ Apr 13 2012, 09:49 AM) *

I can send you one. All stock 1.7 stuff on a bus 2.0.
Changes- GM TPS
GM (bosch) narrow band heated o2
GM air temp sensor.

Its at home though.

Ran good then, IDK if it was totally correct.


That is funny, I'm using 2.0 stuff on my 1.7 biggrin.gif

Sure, upload the VE table if you can export it, change the file extension to .zip and then upload it here.
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