General Supercharger Thread

You need techstream or a bi-directional scan tool

 

Oddly enough, I thought boost season was over, but the truck hit 20.5 today with the A/C on full blast.

 

I'm thinking about adding a second pump to keep the basket full at all times.

 

Man that must be a fun truck to drive. Have you hit the dyno since your build?

 

Not yet, but I'm planning on it. Just a few more tweaks and I'll see what it puts down.

 

Eager to see results! Wondering if you’re at the 7 wheel mark or not. I’m sure she rips

 

Wow! That little 1900 is pushing some air! Wonder what kind of heat it's generating? Was it a real humid day?
You could add another pump like @armyoffoo

 

Got bored so moved the tailpipe from side to rear dump. Was gonna do dump down but heard shit gets blown all over especially off-road. Simple mod to gave me something to do today lol

 

This is correct, had the same issue!

 

Ooofta yeah I did this once at 1/4 tank with the 274 and holes drilled. I hope there is no long term damage in my engine. Now I won’t WOT below like 2/3rd out of paranoia.

 

It was hot today, but not very humid.

 

I have a thread going somewhere talking about options for this... I'm considering scavenging pucks to a small low pressure pump to fill the basket.

 

Holy sheeett sick!

 

Yeah I remember you writing about it. I still have several Walbro pucks like they use for crawlers and snowmobiles. Guess the Walbro 450/267 and dual feed AN 6 fuel lines to the rails are preventing it from leaning out.

 

@snivilous @Mdl quick question, I've noticed while fine tuning MAF table for more/less fuel even at 1% increments the change to A/F can be drastic. Especially up towards the higher MAF volt ranges. Do you guys do half percentages even 1/4 adjustments to get dialed in dead nuts? Thanks guys!

 

Crazy. What are the blower rpms at that boost?
I thought the same when I hit 11 psi on my Harrop last week.

 

I usually adjust MAF solely by the long term fuel trims, so I'm not really using it directly to control AFR. If it's sub 5% I'm happy. The fuel trims will move around based on conditions anyway, so it's kind of pointless to really chase it. I saw a datalog the other day where the fuel trims were within 1% across the board, and the next datalog they were like 4% off.

If your AFR is changing a lot with a small change there's a couple factors. Without thinking about it a lot, the higher the injector constant the more sensitive the changes are I think. For example a high IC will flow more fuel at the same PE, so if you have a high IC your PE might only be at 1.2, so now the functional resolution of PE is only a span of 0.2 as opposed to the full 0.5 range that someone else might be using.

I can't say I've noticed a large change from the MAF table directly, but like I said I don't adjust the MAF table to target a specific AFR (usually), since the fuel trims will work with the MAF table to target 14.7. If you move the MAF table around, then you're also moving the fuel trims around so the net outcome in closed loop should be the same. That's not to say that PE doesn't reference the MAF table, but if I need to adjust the MAF to get more fuel then I'll do that with the MAF Correction table so that closed loop MAF values are still accurate (and by extension fuel trims are low). I don't know if that answered your question....

 

Yes sir that's does answer the question thank you! My IC is quit high and have plenty of fuel! Its WOT at high MAF volts where im trying to get values to my PE of 1.4. Damn close but seems like I swing it either a little lean or rich of the value. Also tried my best to richen up as I build boost. Currently set 25% targeting 10.5 with adjustments to MAF volts. This one's been harder for me since MAF volts is tuned per the LTFT, I've adjusted without going +8/-8. And thank you for bringing up the MAF correction table. I haven't messed with that table at all from the TRD tune other then changing all to 1.00. Now it's on my radar. Just tuned. 005 in some spots for fun, have to see how she reacts.

 

Just as @snivilous stated my my ltft's will be dead on then the next hour or day change. I was constantly adjusting MAF values and PE. So I just decided to only adjust if it is a drastic change or something else is going on. But @snivilous raised my IC to get my PE in check. Like you it's just fine tuning to get it decent...

 

In closed loop I try to stay with trims per @snivilous. Once transitioning into open loop at wot or power enrichment into boost is where I'm trying to nail her down. It's hard to stay within the 10.2-10.6 A/F range in those two senerios for me lol. Always seem to get a bit rich probably why I killed my cat

 

I'll occasionally dip into 9.34 to 9.9 for a second or 3. For some reason with my turbokits MAF I'm having a harder time dialing PE.

 

9.3! Damn that’s low

valdeez kinda low

 

Same here 9.4-9.9 on spool up and then 10.2-10.5. Especially bad after a tune but after some miles and a chance for KCL to learn up settleling back into 10's. My trouble points are low rpm getting into PE and high rpm into shifts to next gear.

 

It would appear a new exhaust fixed the weird AFR oscillation I was getting alternating between the banks.

 

Sweet! It's nice when one new things helps another out instead of causing issues.

 

It's still a work in progress. I had it dialed in pretty solid but I was maxxed put on my MAF.
Switch to @TurboKits.com MAF. @snivilous had to write a new tune as PE was not budging. Just dealing getting PE and getting the W/M to play nice with each other as the psi comes on at different rpm's.

 

That's a pretty narrow range to fixate on. I tell people the AFR average we target is 10.5, but in reality the AFR im happy with is 10 all the way up to 11. Likewise at cruise i tell people that 14 to 15.5 and I'm not worried at all. That's a pretty large range of measurements, but that's how far I see the AFR swing on a "completely dialed" setup. Depending on how you ramp into the throttle, like a slowly increasing throttle vs stomping WOT results in quite a spread for AFR. On my truck I've seen it tap at 9.9, all the way to 11.1, and that's without changing the tune at all and just how the day goes and how I'm using the throttle. Usually it'll hold 10.5 consistently, but it'll still move around a lot the other 20-40% of the time.

The MAF Correction table I started playing with on @helidave tune a couple weeks ago, and have now employed it on a variety of tunes. I try to avoid using it, but it's one of those tricks that you can use to manipulate the MAF values (which again are referenced for fueling) and you can adjust it based on throttle position so it gives you a bit more control than just PE.

 

Since I'm in boost at a lower rpm with the 2.0 pulley. I now have it in the low 11's until 4-5psi then dump try for mid 10's. But sometimes the W/M kicks in and gets into 9's then back into 10's.

 

I still need to test that latest revision you sent. I haven't driven my truck since last monday

 

In low boost im still in the 14 range. Usually dont see richer afrs unless I get on it a bit