I've been playing a little with my HPTuners and so far the truck has liked everything I have changed. So far I basically multiplied the factory timing (high octane) settings by 1.5, then again by 1.1. WOT timing is still a mere 17 degrees, which seems a bit low, even with 87 octane gas.


I was just curious what timing some of you all are running on bolt-on trucks that run regular unleaded, 87 octane?

 

So why did you increase your timing by ~50%? Do you have a wideband? Where you getting knock?

 

i usually tune 87 about 20-23 degrees wot. you'll have to experiment though, some like it and some don't

 

Did you change both tables? WOT on 87 I'm running about 27-28 max with no knock. Different engines respond differently though; smaller engines will take more timing I think.

 

Mark-VI iron-head Bigblock 454, 87 Octane fuel, 180-degree thermostat, 24 degrees timing.
This isn't really relevant to a Gen-III aluminim-headed SBC, but the comparisson is interesting. Bigblocks have such low compression with stock heads that the knock sensors (2) are just ornamental.

 

Cam and full bolt ons I'm running 30 degrees, and have seen as much as 32 with no KR.... But this is with premium fuel. Just for comparison's sake

 

Why? Because I knew 11 degrees wasn't enough timing for anything. The truck was lazy, very lazy. Now it's very spunky. I get no (medium or high load) KR according to datalogs, but I do get a very intermittent 2 or 3 degree Knock Retard out of the blue at light throttle, steady cruise. Still haven't figured that one out yet. I'm assuming it's false knock?

I just wanted to see where everyone else is, as far as timing on their trucks. I'd like to keep running 87 octane, so I'm probably getting close to maxed out.

No functional wideband at the moment.

 

Mine doesn't seem to want anymore, with this lower grade gas in it.

 

No, I just changed the HIGH OCTANE table, and left the other alone. I've heard and read mixed reviews about having both tables the same.

What's your opinion?

 

If I didn't know better...I'd swear I killed my own thread.