Idle too rich.

[inj gtr202]

Hi all.
I've stalked this forum a few times in the past year or 2 as I have just recently rebuilt my 202 and put a new injection manifold and Trottle body on it. I have had the car injected with the VN computer for a bit over 10 years now and has been pretty much trouble free.
I'm a member of the GMH Torana forums as well so if you want a little bit of background as to what I'm running it should pretty much all be covered in this thread. http://www.gmh-torana.com.au/forums/top ... -manifold/

The car runs and performs perfectly if I'm able to stretch its legs every now and then. However I'm starting to find that in heavy traffic it is almost impossible to "open it up" as such so I'm starting to be very picky about my cruise routes.

I don't have any tuning software (or knowledge for that matter). The car has always been tuned by Martin Donnon of Willall Racing.
What I'm really after is some kind of suggestions of what I could do to make the car not run so rich when I'm just cruising and/or when it's idling.

Hope that wasn't too much to swallow in one hit.

thanks

[inj gtr202]

Just realised that thread didn't have the cam spec's..
here is the card

[Holden202T]

without seeing any logs from it or dyno run showing fueling its too hard to say but it sounds to me like theres more work to be done on low rpm fueling!

by the way nice work on the custom manifold fab!

i assume the dyno is on pump fuel ? if so approx 215hp at the wheels on pump fuel is pretty impressive!!

[inj gtr202]

Yep dyno run was on 98.
I don't think too much time was spent on light throttle loads and idle.
I'm tossing up the idea of having a go at tuning myself but obviously don't wan't to ruin the tune it currently has for W.O.T etc. + I don't like the idea of grenading the motor.

[inj gtr202]

Basically is the Delco 808 up to the task? I don't run an air flow meter or O2 sensor...
And is it possible for a novice tuner to spend time tuning it on the road with the use of a AFM gauge inside the car? Or should I just fork out more coin on dyno tuning?
Time really isn't a factor as the car is only used when I want it.. So I am willing to learn the ropes, but just not with the risk of blowing the thing up.

[Holden202T]

the delco is totally capable of doing what you want, and yes if you have the willingness to learn you can do it yourself.

as far as the tune goes you can back it up before you make changes so if a change doesn't work you can always go back to the backup and start again etc.

AFR gauge and the gear to tune the computer is all you need to get started....

the big question though will nbe what software was used to tune it in the first place, if its an after market software you may be able to get the info out and put it into one of the codes we normally use here which is free.

[yoda69]

Looking at the work that went into the manifold, surely welding an O2 sensor boss into the exhaust is not beyond you.

As per Holden202's comments, really need to get an read of th current calibration to understand what the starting point is.
If you can't read it, even a photo of the memcal with cover removed may indicate whether it has a kalmaker style pals setup.

Yoda69

[inj gtr202]

Thanks guy's

I'm 100% sure it's not a Kalmaker. I'll take the cover off and throw a pic of the computer up in the next week or so.
I think I might have a go at this, just wan't to be 100% sure that I can revert back to the original tune if it all goes pear shape.

Yeah, I prolly should have welded a boss on the pipe before I put it all back together.... even if I just plugged it.

Cheers

[blownvp]

Pretty decent cam man.if your running open loop with no o2 get a wideband you could try around 14 to 15 :1 afr light cruise and see if it bucks generally the bigger the cam you run more advance and a bit richer to stop it surging at idle and light cruise.just be aware that the leaner you run it the higher the exhaust gas temperature will be usually not a problem at light cruise cheers darren

[inj gtr202]

That comment about bucking makes it a bit more clear too me as to why it may be running a bit richer than it used to. Since the new cam and manifold have gone on I have found that coasting in gear down to low revs in 2nd gear (going round a round about) I used to be able to leave it in 2nd and coast through at about 1,500rpm. Now I find that unless I'm on the gass, at thoes rev's the car want's to hop a bit.
Also I'm aware that at idle a fair bit of fuel will be getting spewed straight out the exhaust without even going through the cylinders. How can I be sure that by getting the AFR right (being measured in the exhaust pipe) it not leaning out the motor too much?