BUILD THREAD Project Olds Cool (Recognition!!)

Rktpwrd

Builder of Cool Shjt
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Feb 2, 2015
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Well, tonight’s module install and test and tune session went ok.
Not fantastic, but not horrible either.

The first snag I ran into was right after the install of the digital module. As per MSD’s instructions, I tied the grey tach signal wire into the tach wire right at the distributor cap. To program the integral rev limiter, you’re supposed to ground the grey wire for one second at half your desired rev limit, and the module is supposed to program the limit at twice that rpm.
Only problem is, once I ground that wire, it wants to kill the car completely. I mean like shut right off from 3000 rpm. I then disconnected the grey wire from the tach wire and tried grounding it out separately thinking I had done something wrong, but that did zilch.

Quick searching on the interwebs on the issue revealed squat as well. I’m thinking it might possibly have something to do with the tach filter, but I couldn’t find it anywhere in the tach wire unless it’s buried somewhere way up underneath the dash and I wasn’t about to go down that rabbit hole. Not tonight at least.

Moving on, I put the vacuum gauge on a port on the carb, (I think it was manifold vacuum, but I suppose it could’ve been ported vacuum), and started tuning via the idle mixture screws and the idle speed screw.
I tuned for the highest vacuum reading I could get which was no more than about 12 1/2”, but then the throttle response off idle seemed really lazy. It seemed to like the screws backed out more than turned in, so I continued tweaking it from there. I got it to where the vacuum readings were still pretty close to peak, but where the throttle response was fairly acceptable too.

I definitely could not get the vacuum readings anywhere near the 20-22” that Mark figured I could get. 12 1/2” is the best it would do. I set the idle speed to around 900 rpm in park and 750ish in gear, and took it for a spin. From a part throttle whack, the car is plain violent. The trans kicks down, the tires light up instantly and it gets down and boogies. That part of it is plenty fun!

From a standing start, it’ll light the tires up and walk sideways for a good 50 feet or so, but to me it feels more laboured and isn’t as responsive as I’d like. Similarly, I can hear more than feel the secondaries open, but it just doesn’t seem to pull as hard as I think it should with them open. I dunno, maybe it was because by then the car had some heat in the engine and trans. It’s so tough to tell if it’s feeling a bit lazy because it’s running fat, or because it’s not getting enough fuel. Hopefully the new primary jets and secondary rods will help once they get here.

On a side note, the car for the most part gets largely ignored (despite all those months of hard work, probably due to its half primered appearance) but these jackasses in turbo diesel trucks always seem to feel the need to challenge me. And they always lose.
Lol
I had a guy in a Cummins TD Dodge during the test drive tonight that thought he was gonna dust me at a light and cut in front of me before his lane ended. Unfortunately for him, he learned the hard way that wasn’t gonna happen. Once we were moving I simply rolled the throttle 3/4’s on and walked away from him. By the next light, he was suddenly very interested in what I had under the hood!
:LOL:

Anyways, that’s all for now, comments and opinions on what y’all think is happening and suggestions appreciated, on both the digital module issue, and things to try out on the carb.

Thanks all,

D.
 
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Turbolq4

Royal Smart Person
Sep 25, 2017
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I get that junk from Mustang and Camaro guys. Best one yet was a new gt350. Dude got all worked up when he was flat out and I changed lanes drove around him like he was a pedestrian. Super interested in what was under the hood after that.
 
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Rktpwrd

Builder of Cool Shjt
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No one has any thoughts on what’s going on with this HEI digital module?

And no one has had a similar problem installing one in their G bodies? Or maybe I need to create a dedicated thread on this and move it?

MSD tech support is long closed before I get home...
 

TURNA

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Jul 24, 2009
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Rktpwrd

Builder of Cool Shjt
Supporting Member
Feb 2, 2015
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Calgary, Alberta, Canada
I posted a thread asking about this module a couple of days ago.

https://gbodyforum.com/threads/msd-digital-gm-high-energy-modules.69193/#post-634936

Honestly after reading the reviews about it I passed on buying it.

I will most likely use the Davis Unified

https://www.summitracing.com/parts/dui-000222/overview/make/oldsmobile

Sorry cant be more help.

Yep, it was your thread on the subject that got me interested in it, so thanks for that!
No worries on not being able to help, I’m sure I’ll get it sorted out somehow.

Mind if I ask what it was in the reviews that made you decide to pass on it? I can’t get DUI stuff locally around here, and the Canuck buck is at its lowest rate in over a year, so it was MSD or nothing...
 

Rktpwrd

Builder of Cool Shjt
Supporting Member
Feb 2, 2015
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Calgary, Alberta, Canada
The rev limiter on the module looks easy enough to set up and you are doing as per the instruction. I took a quick look on the MSD forum and didn't see anything about the module. You might want to join that forum and see what replies you get.....

https://forums.msdperformance.com/forumdisplay.php?3-MSD-Performance-Forums

That’s exactly what I thought after reading through the instructions as well Steve. Not difficult at all, so I was surprised to get the result I did when I tried to program it.

I also did the same as you afterwards, looked at a bunch of sites (including MSD & MSD’s forum) but saw no mention of anyone else having the same problem.
I didn’t wanna have to join their forum just to ask one question, but I might have to...
 
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pontiacgp

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Mar 31, 2006
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Do you have another tach you can temporarily use to see if you can set up the limiter and then plug your tach back in to see what happens. My timing gun gives me the revs so if you have one of those you can unplug your tach and try to set the limiter.
 
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Rktpwrd

Builder of Cool Shjt
Supporting Member
Feb 2, 2015
4,155
23,832
113
Calgary, Alberta, Canada
Do you have another tach you can temporarily use to see if you can set up the limiter and then plug your tach back in to see what happens

I do, but only in another Rallye pac gauge pod. Interesting idea, that might be worth trying out.
Thanks!
 
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