The CAI on my Jeep Grand Cherokee w/5.7L Hemi:



That's not stock, but FCA's after-market upgrade CAI system. They claim HP and mileage increases. (I didn't add it. The PO apparently did.)

quote:

Originally posted by bigdeal:
The last debate you and I are likely to ever have is on the factory engineering of new vehicles.

Oh come on. You know you love it when I educate you.

CAI work, because it makes that cool BuuuuuuuuughhhhWAAAAAAAA! sound, and louder sounding engines are faster....


JMO but from playing with HP engines, MOtorcycle, V8's Carb and EFI, especially EFI engines, things need to be done in groups to achieve a stated performance goal, a CAI will or should improve the air temp moving into the engine, and theoretically colder air means denser, which means better combustion and power,

However, unless your ECM is programmed to take advantage of that extra air, you might just be leaning out the fuel ratio, not a ton, but some.

Ok now you have all this super cold alaskan air coming into your intake and that cool buuuuuhWAAA sound, you need to get all that extra air out, so unless your stock exhaust was able to flow more, you have a bottle neck, and the result is a minimal gain at top HP RPM.

So now you need a Flowbuster 5000 super duper sewer can muffler that breaths fire out when you line up with Paul Walkers Ghost and Vin Diesels gas roto powered RX...

EFI and O2 sensors on cars, bikes etc are not wideband and the ECM's from factorys are not smart ECM's that read input and output then make significant corrections.

Now you need a Hyperflexy 3000 ECM programmer, with a custom program to adjust to the changes you made to the intake and exhaust and adjust the AFR and timing to provide you with the best power.

Oh you didn't run it on a dyno to fine tune that Hyperflexy 3000 to your engine?

So basically it's louder, has a great BuuuuhWAAAAAA sound, but that doesn't mean you made any more power.

But yer wallets lighter, and lighter cars are faster.....

I installed a hot air intake in my car when i installed the oil catch can. The bottom half of the stock air box is still there so it is pulling air in from the right front grill. but of course the hot engine air is also there. it's a compromise, but i want the OCC since it does collect stuff. For more power I just did a flash tune.



dang, that's an old pic. i need to take a newer pic with the right v-brace reinstalled.

quote:

Originally posted by HRK:
So now you need a Flowbuster 5000 super duper sewer can muffler that breaths fire out when you line up with Paul Walkers Ghost and Vin Diesels gas roto powered RX...

There is a less expensive option...

HRK, the newer cars are a bit smarter than you give them credit for.

I think the Shaker setup is probably one of the more effective setups. Both the Shaker and the air box seal to the hood but the front of the air box that allows cool air coming in from the grill will I'm sure allow some under hood heat. It's not much though as I can watch the intake temps and compare them to the ambient. You can also see them rise a little when stopped in traffic and no airflow is coming into the front of the box.

The car runs great but when you take it out on a 30 degree weather day and that ice cold air is ramming down the Shaker scoop it's obvious how effective it is.

It still has a small opening on the front of the air box that allows in some engine heat.

quote:

Originally posted by HRK:

But yer wallets lighter, and lighter cars are faster.....

When do I make it backfire 47 times every time I let off the gas?

quote:

Originally posted by HRK:
CAI work, because it makes that cool BuuuuuuuuughhhhWAAAAAAAA! sound, and louder sounding engines are faster....


JMO but from playing with HP engines, MOtorcycle, V8's Carb and EFI, especially EFI engines, things need to be done in groups to achieve a stated performance goal, a CAI will or should improve the air temp moving into the engine, and theoretically colder air means denser, which means better combustion and power,

However, unless your ECM is programmed to take advantage of that extra air, you might just be leaning out the fuel ratio, not a ton, but some.

Ok now you have all this super cold alaskan air coming into your intake and that cool buuuuuhWAAA sound, you need to get all that extra air out, so unless your stock exhaust was able to flow more, you have a bottle neck, and the result is a minimal gain at top HP RPM.

EFI and O2 sensors on cars, bikes etc are not wideband and the ECM's from factorys are not smart ECM's that read input and output then make significant corrections.

This is simply false. Yes it can be better to do add on's in groups, but it usually always adds HP/Torque on it's own. The computers on modern cars DO adjust for any changes in air flow and program accordingly. THE MAF (Mass airflow sensor) absolutely measures any changes in air flow into the engine and the computer adjusts, same with the O2 sensors. They do make any corrections needed.....The factory does program the computer to run on the very conservative side of tune, where programmers tend to program closer to the ragged edge of safe and do extract more HP. BUT, I've made 625HP out of a 1993 302 mustang and factory computer before. AND, modern computers have come a long way compared to a 1993 ECM.