Running a WAI through the wringer

[pgfpro]

Nice testing!

Do you have a way to see real time ign. timing values? It would be interesting to see how much timing is being pulled at the higher IAT's

On my car I also had no changes in MPG with IAT values around 127F. I needed a much higher temp to see any gains.

From what I have found, WAI will see an increase on Honda D series and B series engines when you run around 130*F plus IAT's.

The Aromatics, Paraffin's and Olefin's that are used to produce the distillation curve of the fuel and the amount of energy from gasoline will be in three basic groups.

Light Fractions vaporize from 85 to 130 degrees F.

Medium Fractions vaporize from 130 to 250 degrees F.

Heavy Fractions vaporize from 250 to 400 degrees F.

So if you can get over 130 degrees F. you will have all most all the Light Fractions vaporized and some of the Medium Fractions. This will help use more of the fuel that doesn't get burned in the valve relief areas of the piston and some of the outer crown area of the piston without damaging the boundary area.

[FrugalFloyd]

Thanks. Yes, I can monitor ignition timing. It varies when I'm DWLing. If I try to keep it in the high 30s, my mpg will be the best - often in the 50+ mpg range and higher. But I lose speed most of the time maintaining maximum ignition numbers. Cruise control, which I used for today's testing, often drops ignition values into the teens.

I was monitoring FWT, FIA, LOD, and current trip fuel economy. If I monitored ignition, I'm not sure how to use that information in real world driving.

I'd like to know how to get my IATs higher. I'm drawing air from over the exhaust manifold now. I'd have to seal the engine compartment, causing all sorts of unintended consequences, like melting rubber and plastic parts, causing the cooling fan to run all the time, etc.

[pgfpro]

Originally Posted by SentraSE-R

Thanks. Yes, I can monitor ignition timing. It varies when I'm DWLing. If I try to keep it in the high 30s, my mpg will be the best - often in the 50+ mpg range and higher. But I lose speed most of the time maintaining maximum ignition numbers. Cruise control, which I used for today's testing, often drops ignition values into the teens.

I was monitoring FWT, FIA, LOD, and current trip fuel economy. If I monitored ignition, I'm not sure how to use that information in real world driving.

I'd like to know how to get my IATs higher. I'm drawing air from over the exhaust manifold now. I'd have to seal the engine compartment, causing all sorts of unintended consequences, like melting rubber and plastic parts, causing the cooling fan to run all the time, etc.

It sounds like your fighting the stock-code load values. Plus the IAT correction table. For Honda it will pull 3 degrees at 210 degrees F on just the IAT correction table.

When your car goes into cruise control it also looks like it pulls timing.

As for real world driving there's not to much you can do without altering the fuel maps themselves. In which I don't know if they make a system for your car to control that?

As far as increasing the IAT's I don't think you can do much more without going to the extreme that I did and turbocharge the engine. Then you can do some crazy stuff and increase the IAT's over 200 degrees F. But you would have to have some type of engine management system.

[Project84]

Not to butt in on all the technical talk but what about light pressure turbo charging? I believe it was hot a few years back, even with Prius owners adding small turbos and running 4-5psi. The idea was stollen from the OEM work of Saab and Audi.

Anyway... back to a non fantasy world...

Those intake temps won't yield any return as you noticed! I believe all/most cars are put on the road with the capabilities of enduring mother nature's extremes and thus, you'll notice no real gains when driving in those natural conditions. 120's for IAT isn't much higher than what is possible for ambient conditions. Hell, I'd imagine there are a lot of OEM airboxes under hoods of cars that reach that temp when driving in ambient weather. Carbureted engines come to mind specifically. I know the air cleaner on my carbed '84 Camaro would be scolding hot to the touch after a drive.

Without reaching substantially higher than you've done, say in the 160+ range, I doubt you'll ever see a gain. Even when you do reach those numbers, your car may self-adjust depending on your engine's tune and your sensor input.

That all being said, I don't specifically know that the title of the thread fits anymore. I think it should be more about "testing a WAI on a Scion XB", rather than testing a WAI in general. The logic behind the idea of WAI is solid. (I'm happy enough taking the examples the OEM's gave us with the vacuum actuated WAI on old carbureted engines... again, my '84 Camaro was an example of this.)

Whether your specific car allows it to do it's magic or not is the only real question.

[pgfpro]

Originally Posted by Project84

Not to butt in on all the technical talk but what about light pressure turbo charging? I believe it was hot a few years back, even with Prius owners adding small turbos and running 4-5psi. The idea was stollen from the OEM work of Saab and Audi.

This is what I have been working on and so far have had great results.

IMHO I think one can increase FE by a substantial amount by utilizing a turbo charger with engine management. But I'll save this for another thread.

[FrugalFloyd]

Any fuel economy improvements would come from using a smaller engine for normal cruising. If your normal engine is a 1.8 liter engine producing 130 hp and getting 40 mpg at 60 mph, you probably only need 50 hp to push the car at that speed on level ground. So the mfrs like GM and Ford, are planning to replace the 1.8 liter engine with a smaller turbocharged engine.

If you replaced that 1.8 liter engine with a 1 liter, 80 hp turbocharged mill that gets 65 mpg @ 60 mph, and 110 hp boosted. that would be a real economy car.

Can anyone see a reason to retest at 60 mph?

[Project84]

I see no reason to retest unless you can get the temps up another 40*F.

[FrugalFloyd]

Temperatures topped 100 degrees locally for the past 3 days. I took the xB out on Wednesday, and the WAI IAT was in the 168 degree range, but my power went down the tubes, and the coolant temperature hit 238 degrees, triggering the high temperature light to go on. If those high temperatures continue, I'll have to remove my lower grill blocks.

[GasSavers_BEEF]

the IAT temps seem to be around the range that I usually run.

the coolant temps you are talking about are pretty scary to me. I would definitely change something. we have seen quite a few 90+ degree days this past summer (maybe a few 100 degree) and my temps run right around the 190 mark. not sure but I think I have a 195 thermostat.

it really isn't worth screwing up your motor. I will say that you stayed with it and gave it a descent go but maybe it is time to move on from this as your intake temps probably are pushing your coolant temps up at least to some extent.

and power does go down the crapper. once you hit the 200ish mark for IAT, you really notice it.

[add|ct]

I agree with BEEF.