DIY Warm-Air Intake

[13B_88FC]

Lol.. Ricer boy? Please, calling an rx7 a ricer is like calling a Lamborghini a muscle car. I mean seriously, these cars would just melt the glasspacks that people put on their gay ass hondas.

I figured you weren't trying to build a racing machine when you mentioned you had a jeep.

Of course your sly stereotypes about me driving around at WOT all the time are completely dead on... except not. Although to be honest, my fuel mileage is hardly affected by how hard I drive my car, unless of course it's just being turned into heat in the brakes. My car loves to rev... and you have to get up to speed somehow whether it be slowly at an arguably efficient engine speed or quickly at an arguably inefficient engine speed... it ends up being pretty damn close to the same amount of fuel used


I think there is an intake air temperature that is "warm enough" and gives optimal fuel evaporation when the engine is warm. A warmer air intake will help warm up the engine quicker and it will help in very cold climates. Most of the time though, I don't think it is necessary or will do much good.

Thanks for letting me know about the jeep engine's fuel injection systems.

[razor02097]

Glass pack mufflers are a great viable option for high performance applications in the racing world. They are free flowing, light weight and just enough to let the person abide by the noise restrictions many race tracks have put on different classes of vehicles.... They are tough, simple and robust. I would love to see a rotary try to melt one.

Accelerating at 2 different rates isn't necessarily going to use the same amount of fuel. Especially if you end up going in to enrichment mode during the acceleration. Turning the engine at lower revs utilizes the engine more efficiently than turning it at higher revs. You don't want to lug the engine though that will retard the timing which lowers power and the ECU will add a lot of fuel to prevent damage which would waste fuel.

[Davinator61]

Originally Posted by 13B_88FC

Lol.. Ricer boy? Please, calling an rx7 a ricer is like calling a Lamborghini a muscle car. I mean seriously, these cars would just melt the glasspacks that people put on their gay ass hondas.

I figured you weren't trying to build a racing machine when you mentioned you had a jeep.

Of course your sly stereotypes about me driving around at WOT all the time are completely dead on... except not. Although to be honest, my fuel mileage is hardly affected by how hard I drive my car, unless of course it's just being turned into heat in the brakes. My car loves to rev... and you have to get up to speed somehow whether it be slowly at an arguably efficient engine speed or quickly at an arguably inefficient engine speed... it ends up being pretty damn close to the same amount of fuel used


I think there is an intake air temperature that is "warm enough" and gives optimal fuel evaporation when the engine is warm. A warmer air intake will help warm up the engine quicker and it will help in very cold climates. Most of the time though, I don't think it is necessary or will do much good.

Thanks for letting me know about the jeep engine's fuel injection systems.

You're driving a Mazda RX7? DEFINITELY a Fart-Knocker Ricer BOI...lollollollollol! But seriously, Mazda RX7s ARE also a Japanese design, as well as import. Also I still STRONGLY disagree with your notion that my WAI idea is not necessary nor will do my Jeep any good. So now the Comparison War Gauntlet would seem to have been thrown down...let the Flames of WAI Fuel Conservation v.s. CAI Gas Guzzling War of Words begin!

[t vago]

Originally Posted by razor02097

Accelerating at 2 different rates isn't necessarily going to use the same amount of fuel. Especially if you end up going in to enrichment mode during the acceleration. Turning the engine at lower revs utilizes the engine more efficiently than turning it at higher revs. You don't want to lug the engine though that will retard the timing which lowers power and the ECU will add a lot of fuel to prevent damage which would waste fuel.

Another thing - assuming that a given engine does not go into enrichment, brisk acceleration does tend to use less gasoline than accelerating slowly. Brisk acceleration tends to put the gas engine closer to peak BSFC than slow acceleration.

[13B_88FC]

Originally Posted by razor02097

Glass pack mufflers are a great viable option for high performance applications in the racing world. They are free flowing, light weight and just enough to let the person abide by the noise restrictions many race tracks have put on different classes of vehicles.... They are tough, simple and robust. I would love to see a rotary try to melt one.

Accelerating at 2 different rates isn't necessarily going to use the same amount of fuel. Especially if you end up going in to enrichment mode during the acceleration. Turning the engine at lower revs utilizes the engine more efficiently than turning it at higher revs. You don't want to lug the engine though that will retard the timing which lowers power and the ECU will add a lot of fuel to prevent damage which would waste fuel.

I agree glass packs are good muffler solutions, however it is common knowledge that rotary engines melt them very quickly (anywhere from a few hours to a couple months) unless they are very high quality. They're just commonly associated with "ricers" which is why I brought them up.

I didn't say it would use the same amount of fuel, I said about the same amount. Most people over generalize and say that accelerating quickly is bad for fuel economy. Gasoline engines are more efficient at high load - they're making the most POWER per unit fuel burned when they're working hard, however the higher you rev, the more of that power is going towards counteracting the friction of the engine. In my opinion, the most efficient acceleration would be to sandwich the toque peak between shifts since that's where you're making the most power per RPM.

My stock peak torque is 3800rpm, right before my 5th and 6th ports open up. however my engine has a decent sized street port which probably raises the torque to around 4500 or maybe more; it seems to really pick up around 5k.

"enrichment mode"
A well tuned engine should (key word here is should) simply inject a linearly proportional amount of fuel based on the air flowing into the engine. Why would there be an enrichment mode? As far as I know, your air/fuel ratio should remain pretty constant throughout the power curve of the engine.

[13B_88FC]

Originally Posted by Davinator61

You're driving a Mazda RX7? DEFINITELY a Fart-Knocker Ricer BOI...lollollollollol! But seriously, Mazda RX7s ARE also a Japanese design, as well as import. Also I still STRONGLY disagree with your notion that my WAI idea is not necessary nor will do my Jeep any good. So now the Comparison War Gauntlet would seem to have been thrown down...let the Flames of WAI Fuel Conservation v.s. CAI Gas Guzzling War of Words begin!

You're driving a jeep, of course you view every import car as a ricer. No ricer is faster than the mustangs and camaros of the same year, not to mention much better handling. Ok, ok, so probably only the turbo rx7's were faster, but still.

I never said YOUR jeep. You say it works for your car, then I believe you, which I have said previously.

I think we both have the right ideas, we just disagree on specifics. There is no golden rule. Cars are different, there are way too many variables.

[ciderbarrel]

My lifetime average with the CAI on my Mustang has been 20.4. My last two full tanks have been with the stock airbox back on and I will do a WAI after I am done with this tank. The two stock airbox tanks were 22.4 and 22.6, (647 miles on 28.722 gallons for 22.5 MPG across these two tanks) in winter, 45/55 city/hw driving.

A comparable tank from last fall/winter was in Oct when I did 19.8 on 40/60 driving. I did a 16.3 last Feb but that was 100% city.

A comparable tank from summer was 20.7 MPG on the 3rd of July with 50/50 driving.

I love that I'm beating a warm weather CAI tank in winter with the stock airbox.

[13B_88FC]

Originally Posted by ciderbarrel

My lifetime average with the CAI on my Mustang has been 20.4. My last two full tanks have been with the stock airbox back on and I will do a WAI after I am done with this tank. The two stock airbox tanks were 22.4 and 22.6, (647 miles on 28.722 gallons for 22.5 MPG across these two tanks) in winter, 45/55 city/hw driving.

A comparable tank from last fall/winter was in Oct when I did 19.8 on 40/60 driving. I did a 16.3 last Feb but that was 100% city.

A comparable tank from summer was 20.7 MPG on the 3rd of July with 50/50 driving.

I love that I'm beating a warm weather CAI tank in winter with the stock airbox.

What kind of cold air intake is it? Is it just heatshielded or is it taking air directly from the outside?

[Davinator61]

Originally Posted by 13B_88FC

You're driving a jeep, of course you view every import car as a ricer. No ricer is faster than the mustangs and camaros of the same year, not to mention much better handling. Ok, ok, so probably only the turbo rx7's were faster, but still.

I never said YOUR jeep. You say it works for your car, then I believe you, which I have said previously.

I think we both have the right ideas, we just disagree on specifics. There is no golden rule. Cars are different, there are way too many variables.

Definitely NO Absolute Golden Rule in THAT regard, just a general rule of thumb, with plenty of exceptions, especially with fuel injection systems and MAFS versus MAPS (my Jeep uses a MAP Sensor,which seems to like WAIs, instead of a MAF Sensor, which does not seem to like WAIs). Also, the thing to remember is that a Turbo-charged Rotary, or Wankel engine is quite a bit different from a naturally-aspirated inline-six reciprocating engine design, like what I have on my Jeep. Even though they do basically the same thing, i.e. pushing your vehicle down the road, they operate by somewhat different principles.

I remember one of my Automotive Technology teachers telling me about how fuel inefficient the first Mazda/Wankels were when they were introduced, and how they had a bad tendency to produce more smog than an equivalent displacement piston engine. He also touched on the inferior grade of materials used in their engine block-segment-to-block-segment seals. However, the high RPMs range was where they had their equivalent piston engine cousins beat, in both HP and Torque. It was not uncommon for a two-rotor Wankel to push 200HP near a VERY high Redline RPM and there was even a four-rotor design that would have put out as much as 400 HP, had it been utilized to any serious degree (never heard back about THAT one, though).

Buuut, compairing your Mazda RX7's Turbo Rotary/Wankel to my Jeep Cherokee Laredo's 4.0L Inline-Six is like compairing apples to kumquats, in my personal opinion, as a different set of rules MAY need to be applied to YOUR vehicle's engine in order to improve it's fuel efficiency over what it is currently. Plus if your engine uses a Mass Airflow Sensor, instead of a Manifold Absolute Pressure Sensor, as what's on my Jeep's intake manifold, your R/W may NOT likey the WAI that my Jeep 4.0L MAY likey. Understanding this MAY help you find your own solution(s) to your potential Gas-Guzzler issues, besides just driving like you've got a raw egg under your accelerator pedal, which I do to some degree as part of my modified Hyper-Miler regimen anyways. Hope this helps, even if only a little...

[13B_88FC]

Yes, two completely different engines, that I wasn't trying to compare.

the later model 13b twin turbo's in the 3rd gen rx7 produced up to 276 hp (limited by japanese regualtions)

There were no 4 rotor street engine produced by mazda, however their 787B which won lemans (and of course was later banned) was a 4 rotor NON-turbo with 650hp.