Newbie help

Tuning concepts, methods, tips etc.

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davewhitehouse
MS/Extra Newbie
Posts: 3
Joined: Fri Jul 15, 2016 6:11 am

Newbie help

Post by davewhitehouse »

Hi all, I'm trying to get my head round my megasquirt installation on an MX5. It's a 1999 1.8 with bike throttle bodies.

The car hangs on to revs when the throttle is blipped and I can't work out why. I've been looking at some log data but can't quite understand why the DutyCycle seems to be at odds with the pulse width some times. I'd have thought that these two metrics would follow each other. Car is running Alpha-N so pure tps load.

I've added some log output in the hope that someone might be able to point me at the issue and a fix.

Cheers.
turbo conversion
Super MS/Extra'er
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Location: White House, TN USA

Re: Newbie help

Post by turbo conversion »

Can you post a current msq?

David
1976 Datsun 280Z L28ET Garrett GT35R T3-T04E stage3 50 trim 63 A/R housing custom grind cam 2000-6000 rpm 440cc injectors intercooled 18 lbs. boost
3" exhaust turbo back LC-1 o2 sensor Hallman manual boost controller EDIS 6 ignition batch fire 60mm throttle body 5 spd T5 borg warner 3.54 lsd
davewhitehouse
MS/Extra Newbie
Posts: 3
Joined: Fri Jul 15, 2016 6:11 am

Re: Newbie help

Post by davewhitehouse »

turbo conversion wrote:Can you post a current msq?

David
Yep, sorry. Attached.

Thanks
Matt Cramer
Super MS/Extra'er
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Joined: Thu Apr 16, 2009 8:08 pm

Re: Newbie help

Post by Matt Cramer »

What, if anything, are you using for an IAC valve?
Matt Cramer -1966 Dodge Dart slant six running on MS3X
davewhitehouse
MS/Extra Newbie
Posts: 3
Joined: Fri Jul 15, 2016 6:11 am

Re: Newbie help

Post by davewhitehouse »

Matt Cramer wrote:What, if anything, are you using for an IAC valve?
It has no Idle control valve.

I've got it running better by equalizing the ignition advance at closed throttle. There was a large variation and a big jump from 5 deg to 26 deg around 2000 revs. Retarding the ignition over 2000 revs now brings the revs down faster when the throttle is closed.

I'm going to put my vacuum gauges on it and check the balance next.
hobieboy
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Joined: Mon Jun 27, 2005 1:13 pm
Location: Up North

Re: Newbie help

Post by hobieboy »

Didn't download your MSQ but if retarding timing works for you to bring down RPM, have you tried enabling Advanced Idle Setting so you can run less timing during idle, and keep the off-idle timing higher?
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