My K1500 DD Tow Pig

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Supercharged111

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Ive had several issues going MAF only with the older PCMs. it works good with the E38 ECMs tho.
I stuck with OLSD for years and it seems to be the easiest way to tune for me.
I spent 6 days in the Holley EFI training school and now i just want to put a Holley ECU on everything. Ordered a couple Dominator ECUs for some my trucks to really have some fun.

They do eliminate the quirks of the 411, I've thought fondly of a Holley on numerous occasions.
 

Supercharged111

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If you do go that route let me know and I can help you out.

Will do, but my cheapness will probably prevent that for a while. I've worked with a couple standalones in the past and they were simpler, way less 2nd/3rd order effects to worry about.

The open loop enrichment seems to be working out very nicely. Gotta check airflow in gear at idle to sanity check the existing tables. Next would be a semi-scientific reattack on the transient fueling, but I'll already be on the road.

Also plugged my VSS into the 4L80 output sensor instead of the t-case. This made 4Lo act right, but the speedo reads off. Easier than the witchcraft I would have needed to pull off with the PCM. Still thinking I need to try that though. This only worked because the donor trans started life as a 2wd. They have a reluctor on a drum for the VSS that the 4wd does not.
 
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Supercharged111

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I decided on my Z06 I wanted to log when hp was falling off to determine my optimum shift point after the cam swap. I'm thinking I want to do the same before the swap as well, I'd love to see the airflow curve before and after. So I figured out how to make a PID that would spit out hp. GM already calculates delivered engine torque. Who cares if it's accurate or not, all I need to know is how fast it's rising and falling to see where the optimum shift points are. I've been using V7.5, but custom PIDs look like witchcraft so I cracked into the V8 software I'd been avoiding using because I didn't feel like remaking all my histograms (which is super easy BTW). As suspected, V8 is a bit more user friendly once you get to know it. The custom PIDs don't require you to have a programming cert. But I was having connectivity issues with the Z06, so I said screw it let's try it on the truck and it worked so I went out for a rip and this is what I got on a 1-2 shift.

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I told myself the numbers didn't matter until it claimed it was cranking out 440# of torque and 362hp here at altitude. Who knows how optimistic those are. Torque peaked from 2800-3400 RPM and HP at 5250. I was commanding a 5200 shift, got a 5300 shift. I'd monkeyed around with that a bit end of last year and kept over/undershooting my target no matter what I did with the mph and RPM points. I'd had the limiter set then at 5400 and would occasionally bounce off of it. I bumped it by 200 up to 5400, we'll see if it shifts there or closer to 5500 and also how the hp is falling off up there. I'm curious @L31MaxExpress didn't you run the Ramjet cam with marine intake on a 350 at one point? Curious where yours wanted to be shifted at. Of course the blower could be artificially stringing this along too.
 

OutlawDrifter

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I shift around 6400rpm in my Z28. Peak HP is 6500 and flat for a short while and then it starts dropping off around 67-6800. Rev limiter is set at 7k. It runs faster shifting at 6400 than it does at 6800.

Cam is a 230/232 @ .050 .585/595 lift on a 112 with a +4 advance built in.
 

0xDEADBEEF

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If you have a dyno chart and know your gear ratios, you can scale it in each gear and then chain them together. I think it's more about your gears than it is about engine output.
 

Supercharged111

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Shift points? That's easy ... right before the rev limiter. :)

I can set the limiter wherever I want.

I shift around 6400rpm in my Z28. Peak HP is 6500 and flat for a short while and then it starts dropping off around 67-6800. Rev limiter is set at 7k. It runs faster shifting at 6400 than it does at 6800.

Cam is a 230/232 @ .050 .585/595 lift on a 112 with a +4 advance built in.

That's bass ackwards. My Z ought to be peaking around 6000 and without even data logging it I bet it's fastest shifted in the 6600-6800 range because it just hangs on and on. It feels flat behind the wheel, but that's because the tidal wave is over. I'd bumped the rev cut years ago from 6600-6900. But this is about my truck in this thread. I'll head out for a log in a bit and see how it likes being shifted 5400-5500.
 

Supercharged111

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If you have a dyno chart and know your gear ratios, you can scale it in each gear and then chain them together. I think it's more about your gears than it is about engine output.

So if you look above I have a Dyno chart. And for the gears, I have an Excel spreadsheet for that.
 
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