Another S/C'd member worried about his AFR

[Nexus1155]

it seems like proper tuning would net this supercharger alot more power. people who arent running as lean as other nets 10 more hp?! imagine if you were actually running well...

[PETERPOOP]

That's our goal!

[LtNoogie]

Most likely ignition timing at different RPM during WOT. We might be able to compare this to his air/fuel ratio from the dyno run.

[Doc Zaius]

I was pretty sure that lean = more power..? But more dangerous.

I still have yet to buy gauges, so I can't be any help to you guys right now. Although (interestingly, whoopeee) I remember taking some rubber line off something and there being a fair bit of oil/muck inside it. Don't know which line. But perhaps I should get an oil catch-can too.

[PETERPOOP]

Originally Posted by Doc Zaius

I was pretty sure that lean = more power..? But more dangerous.

The guy who did my dyno was saying all cars are different. Some guys make their cars run lean because their car responds with more HP when it is lean. Other guys lose HP when it is ran lean. I guess the Yaris is the case of a car losing HP when running lean at higher RPMs.

[LtNoogie]

I've contacted my dyno guy to see how much he charges to tune this little beast. Afterall, it's now my little project car.

As a side note, I set the S/C to OFF this morning when I got on the freeway. I did not see any ignition retard down to single digits. I am only guessing but this tells me that the ECU is sensing pre-igition during boost and is retarding the timing, which is what my pictures showed in the other thread. That can't be good for engine life or max power output. When there's no boost and no pre-ignition, the ECU leaves the inigition timing in the low to mid 20's.

[Nexus1155]

I was pretty sure that lean = more power..? But more dangerous.

There needs to be a harmony, thats why theres a recommended range for supercharged vehicles

More fuel = more allowable ignition advance.

You ideally want no knock correction as it takes the ECU a bit for every degree of correction where you lose a severe amount of power. It should really be checked on the cars with misfired on how bad it is!!!

[yaris-me]

Hi Long. Have you considered maybe one of your fuel injectors might be clogged? I try running a high quality injector cleaner in your gas and see if the condition improves. You are trying to eliminate all variables?

[whooppee777]

could the power enterprises camcom correct a/f ratios by manually advancing or retarding the timing?

[CASTREX]

Originally Posted by whooppee777

could the power enterprises camcom correct a/f ratios by manually advancing or retarding the timing?

To correct the AFR you need to add or sustract fuel not timing.

However, by sustracting enough timing you can make the car run safe even with those lean AFR's you guys are seeing.

Theoretically you could tune the car with the Camcom... however, I haven't seen any camcom sucsesfully installed in a Yaris.... yet.

Some times you can find those for cheap on ebay... it worths a shot.

[whooppee777]

Originally Posted by CASTREX

Theoretically you could tune the car with the Camcom... however, I haven't seen any camcom sucsesfully installed in a Yaris.... yet.

the tein yaris had one successfully tuned with the camcom, it got like an additional 10 wheel hp/10 pounds of torque its in an issue of siphon. i cant remember who tuned it though

[whooppee777]

Originally Posted by Yaris T-Sport

yeah, but the Tein yaris has the Greddy SC instead

yea i know but before the supercharger it was using the camcom, thats the important thing people either dont know or seem to forget

[LtNoogie]

I can't wait to see what a properly tuned Blitz'd Yaris can put out. I know we've been admonished not to put larger injectors on this car but hear me out on this theory.

What if the current fuel system with the Blitz piggyback fuel controller cannot pump enough fuel into the cylinders during WOT, leading to a lean condition. The ECU detects pre-ignition and has to retard timing to protect the engine, and as a consequence robs us of the maximum power the S/C can put out.

If I put slightly, not hugely, larger injectors in the car, it may run less lean during WOT and the ignition retard is less, giving more power. During idle or light throttle, the ECU detects a rich condition from the O2 sensor and is able to dial back the fuel to maintain proper AFR. Remember, I said slightly larger injectors, not fire hoses. If the increase in fuel is within the ECU's cabability to control, that could just work.

Anyhow, that's the theory I want to present to my dyno guy if I have him tune the car.

[CASTREX]

Garm's car has been running with TC injectors on the OEM ECU right?

And iirc he didn't had any idle or part throttle problems... just a lean condition at WOT... but that was @ 180 whp

I say your theory is worth a shot if you can find some injectors for cheap.

Look for injectors from a Celica GTs, corolla/ matrix XRS. I think those are a little smaller than the TC's.

You can look into the 6 gen celica forums for those..

[RagnaCaT]

Originally Posted by LtNoogie

I can't wait to see what a properly tuned Blitz'd Yaris can put out. I know we've been admonished not to put larger injectors on this car but hear me out on this theory.

What if the current fuel system with the Blitz piggyback fuel controller cannot pump enough fuel into the cylinders during WOT, leading to a lean condition. The ECU detects pre-ignition and has to retard timing to protect the engine, and as a consequence robs us of the maximum power the S/C can put out.

If I put slightly, not hugely, larger injectors in the car, it may run less lean during WOT and the ignition retard is less, giving more power. During idle or light throttle, the ECU detects a rich condition from the O2 sensor and is able to dial back the fuel to maintain proper AFR. Remember, I said slightly larger injectors, not fire hoses. If the increase in fuel is within the ECU's cabability to control, that could just work.

Anyhow, that's the theory I want to present to my dyno guy if I have him tune the car.

This is the smartest post, try OEM injectors from a 1.8 like corolla or XD could help you out??? i would go for it I swapped camry 2.0 3S-FE injectors on a corolla 1.6 4A-FE modded and got almost 2 hp at WOT and that was an N/A setup you are FI

[whooppee777]

at a local auto-x event this weekend i had a nice chat with a turbo charged xa and he told me that he was running the blitz supercharger with nitrous before going turbo (he's blown his engine 5 times)

he said he had a lot of issues with the belt slipping and asked him about a/f ratios and he said that the blitz kit really has the stock injectors pushed to its limits.

now this guy also works at the shop in northern virginia which has a high reutation so this isnt some averge joe, hes a tech at this shop that knows what hes talking about.

sounds like bigger injectors r the way to go and a stronger fuel pump would also help. an adjustable fuel pump is not an option on our cars. see cali's thread on his turbo build for the explanation

[bearda]

Originally Posted by whooppee777

now this guy also works at the shop in northern virginia which has a high reutation so this isnt some averge joe, hes a tech at this shop that knows what hes talking about.

Which shop is he running out of? Ptuning?

[Doc Zaius]

^^^ Quite excited about the sound of that!