General Supercharger Thread

Question for you guys with an AFR gauge (particularly anyone with the PSB-1): Have you recognized a delta between the ECU's AFR and your gauge's AFR?

I recently installed the full SPD exhaust and have finally been able to use the wideband with the PSB-1. I've found that the PSB-1 displays the AFR as being leaner by 0.3-0.4 points (+0.020-0.027 Lambda) compared to the AFRs displayed by my SG3 (I monitor both banks with the SG3).

I've done a full recalibration a couple of times (including removing the sensor from the exhaust into clean air) with the same results. I have an Innovate ECF-1 arriving sometime this week, which can also measure AFRs, and plan to compare its figures to the PSB-1.

I just find it odd that the AFRs from the ECU, for both banks, hover around commanded AFR while the PSB-1 is +0.3/0.4 points leaner. My O2 sensors are less than a year old.

 

Hmmm. My AEM afr gauge is off a few tenths from stock O2's.

 

Where is the PSB-1 sensor mounted? Mine reads within 0.2 probably, though the two sensors are right on top of each other.

 

Mine seem pretty close. Within a tenth or two when I bother to compare. I think the different sensors have different sample rates, but they seems to follow each other

 

Same as @snivilous and @helidave . My PSB-1 one reads pretty darn close - +_.1 or .2. I did recalibrate it a few times when setting it up and seemed to dial it in. I believe Innovate has note about recalibrating the wideband every 6 month or so. Maybe try recalibrating it and see if get's closer? .4 points seems pretty far off to me.

 

The sensor is mounted after the cat on bank 2. I'm kidding. The bung is roughly 6" downstream of the truck's wideband O2 - so about 10-ish inches from the header flange, on bank 2. I'm open to suggestions for placement on bank 1 (adding a bung with the addition of the ECF-1).

Yeah it appears the PSB-1 refreshes a bit quicker. At idle, occasionally I'll see 15.X on the PSB-1, but I have yet to see anything above 14.7X on the SG3. Maybe it's that moment's difference between their sample rates.

I installed the sensor on Sat. I did the initial calibration process and then drove around for a bit. It was reading lean, so I did the whole recalibration process again (sensor in open air). Drove it around and it was still +0.3-0.4. I wish it were only ±0.1-0.2, because you're right, 0.4 seems high.

I'm hooking up the PROLINK+ sometime this week and hope to have a better comparison with data logging.

 

Did you use the bung that Innovate supplied? IMO it's too tall, and the combination of that and the offset from the truck's sensor might be your issues. I cut the bung supplied down a LOT



Without cutting it down the O2 sensor ends up about flush with the end of the bung, so flush or a little set back from the actual exhaust tube, kind of like those O2 spoofing devices. With it cut down this far the sensor is well into the exhaust stream, similar to the stock sensor:



Not to say there's any issue with how yours is setup, but MAYBE that's contributing? And food for thought for your new sensor placement then.

 

I used the tertiary bung provided on the SPD exhaust, which appeared to be shallow. And thank you for pointing that out about the Innovate, as I was thinking it was too tall as well! I'll have to hit it with a deathwheel or grinder before install.

 

Thanks for the post. Gives a little bit on airload/torque relations that @snivilous explained and has been doing for the larger throttle bodies. Helps it sink in a bit more...

 

And if it's off on hpt you can transform the calculations to get it spot on. With my older AEM gauge I was off on both boost and afr's. Was able to fine tune it so it would be accurate to tune.

 

Anyone knkw if these shorties will fit an 18. they have it listed 2007-2017

 

I know Doug Thorley Tri Y shorties fit. Didn't know anyone else made shorties for our trucks. The ones in the image don't look like much of an improvement over OEM.

 

They should but you already have shorties with the stock ones...but those look better.
I'd cut those air tubes off. Except for last 2 and plug the rest.

 

Which 2?

 

Air tubes by 7 and 8 by flanges. It makes it so much easier to get on and off, better access to manifold studs. I believe ARH has that setup with one air tube only on 7 and 8.
If I ever get new LT's or need to take my JBA's off those air tunes are history.

 

When you look at the raw data from the prolink, you'll see just how fast the wideband is updating. 12x a second if i remember right. So it jumps around a lot more than the stock O2s

 

Get the part number and do a google search. I did that with my Maggy 1900 and found one at a dodge dealer for $2k less than anywheres else. Brand new in the box.

 

I put up an explanation of what IDC is from a site that explained it perfectly. Basically IDC is the amount of time the injector is spraying during the stroke cycle. So 100% would mean that as soon as the piston starts to go down on the intake cycle, the injector starts spraying fuel. It will spray till the piston is all the way back up. Anything pass 100% means it is still spraying after the piston has gone up and started to go back down. Less, 80% means it's spraying for 80% of the cycle. So its not that injectors are maxed out per se, like some believe, its just that it cant spray the amount it needs in a given time frame.

 

This sounds like a feasible explanation. Interesting.

What would be the purpose/advantage of spraying so early after combustion on the intake stroke?

 

It's not maxxed out but is spraying 100%...and spraying beyond its calculated range. Why would you spray for the entire intake cycle giving the ecu a chance to mis-calculated the ipw. I ran quite a bit with the injectors operating at 100% with no harm but didn't feel like taking the chance. Buy I agree that idc is misunderstood.

 

https://www.tundras.com/threads/general-supercharger-thread.85513/page-518#post-3583989

Go to post 15530.

 

I am close to 100%, closer than I would like to be after reading up on IDC. I just switched over to boost reference, but haven't had a chance to do a run log so @snivilous can recalibrate. But my AFR is showing high 9-10.5+/- so at least I am safe in the AFR side. But my OCD side tells me to be even safer and get my IDC down. At some point I will drop down in pulley size and upgrade my injectors and pump.

 

Looks like Headers + larger exhaust dropped my IAT from delta +28-32* down to +15*-20* over ambient. Shocked.

 

this is data that me & my wallet don't need.

 

ballpark the logic here.

what variables would/could be causing an IAT decrease?

what heat is going away?

or is there more flow?

 

10* is about 1% HP. ️
Funny thing is I saw no IAT change with the restrictive OEM exhaust. Exhaust is the only change I’ve made.

 

Probably less restriction more flow. I’ll mind my PSI see if I notice a drop. Didn’t have a boost gauge preheaders so hard to say how much of a drop in restriction in terms of PSI.

 

What’s odd is the bypass is pretty much always open unless you’re really in the throttle, like cruising or normal driving shouldn’t get you into boost and increase your IATs from the aspect of resistance to flow = heat. I can avoid getting into boost for an entire drive and I’ll still see 28 over ambient just from the hot intercooler fluid picking up heat from the engine bay and dumping it into the intake air. Makes me wonder if there are other factors at play.

 

Could very well be something else is going on. Only other thing I can think of is my temp sensor is shitting the bed. I've had the headers on for over a year and never noticed lower temps.

Drive in was practically ideal almost purely highway driving never stopping. On the way back was almost entirely stop and go. Temps swung the other way about +40 over ambient usually due to high trans temps.

 

Reminder to all to remove the restrictor jet nozzle thingie from the bypass hose!

Restrictor jet mod:
A now well known (and free) mod which involves removing hose from factory bypass valve in the rear of the supercharger to a port in the rear of supercharger itself (On Tundra it's in the FRONT of SC). There is a small brass colored restrictor jet either stuck on the bypass valve vacuum port, or gets sucked into the hose. Remove it for better overall vacuum at idle and cruising, better bypass valve functionality (now moves as quick as the throttle body can) and better boost consistency. Added bonus is you gain back boost you should have with the pulley in place. Tested and run by yours truly, no problems.