Cold Air Intakes: Pros And Cons?.

[tbayer2010]

I am a new Lexus IS250 owner and I am interested in installing a cold air intake. What are the thoughts on this? How good is the HP increase and is the savings in mpg just a myth?

[LEX-SV]

Isn't the standard intake a cold air intake?

[RegRover]

All it adds is sound and if it does add a few HP's, can not even notice it.

[reyoasian]

Isn't the standard intake a cold air intake?

To answer OP and to correct LEX-SV...

There is no true COLD air intake made for the IS

All aftermarket intakes are just a shortram

A true cold air intake usually runs longer piping and to the bottom part of the engine bay away from the engine in order to get "colder" air (because heat rises)

Now there is a member on clublexus who has done a custom true cold air intake you can take a look

http://www.clublexus...lter-setup.html

Now for LEX-SV...he has a point but not fully true.

Stock intake is not a "cold air intake"...it is simply "colder" compared to ANY aftermarket intakes because it gets air from directly OUTSIDE of the car (if you've looked at the design of our intakes you would know what I mean)

However, it doesn't get air from outside + BOTTOM of the car, and there is still interference from engine heat

Compared to aftermarket intakes which get air from inside engine bay which is like hot from the engine

That's why a lot of people just get a Joe-Z Intake pipe and put in a K&N, FSport, HKS, etc. drop in filter (technically same setup as the FSport intake) because you're running an aftermarket pipe which is where the the gain in power comes, while maintaining the "colder" air from stock intake box

This setup doesn't add any noise or growl so some people get the FSport intake box and filter only and use it with the Joe-Z pipe, or simply use stock airbox and cut a hole (if you compared stock and FSport intake box, they are EXACTLY the same except for that hole in the FSport which adds the noise)

Many options available for aftermarket though (Takeda, Injen, AME, AFE, etc.)

But I particularly like the K&N Typhoon because their intake comes with a heat shield which actually does something (I've went for long and hard drives and after put my hands on both sides of the heat shield and the engine side is noticeably warmer than the intake filter side)

As well it's got an amazing growl, makes the V6 sound V8

Only downside is the cleaning part which requires re-oiling....

As for power, all intakes add more or less about 5WHP (Joe-Z pipe with stock airbox dyno proven to add about 6ish for IS250 and 4ish for IS350)

Most intake companies claim 10, 12, etc. HP gain is really just marketing BS

Even taking into account of power loss from the average 5 WHP, is really just 6-7 BHP gain

so 5HP is nothing you can feel in real life at all, people just do it for the sound really as well a better air:fuel ratio because you're intaking much more air into the engine as the stock tube restricts a lot of it

ANyways, yeah...

[LEX-SV]

reyoasian - Thanks for report on intakes. I won't be wasting time/money with these aftermarket hack intakes.

[reyoasian]

reyoasian - Thanks for report on intakes. I won't be wasting time/money with these aftermarket hack intakes.

Not really a hack intake :)

Even though the intake is sucking in warmer air, but the amount of air being sucked is a LOT more than stock because the pipe is smooth instead of ribbed (which restricts air flow) as well if you compare an aftermarket pipe and stock rubber pipe there is a part that comes out on the side which restricts airflow even more

Therefore the power gain overpowers the power loss, which is a net gain

Especially good for winter with a clean filter since air is so cold

[LEX-SV]

reyoasian - Thanks for report on intakes. I won't be wasting time/money with these aftermarket hack intakes.

Not really a hack intake :)

Even though the intake is sucking in warmer air, but the amount of air being sucked is a LOT more than stock because the pipe is smooth instead of ribbed (which restricts air flow) as well if you compare an aftermarket pipe and stock rubber pipe there is a part that comes out on the side which restricts airflow even more

Therefore the power gain overpowers the power loss, which is a net gain

Especially good for winter with a clean filter since air is so cold

Yes, sounds like so-so engineering to me, especially considering the resources of these aftermarket hacks is nowhere near the resources available to engineers at Toy/Lex for example. Don't need a high volume hot air intake.

[reyoasian]

A little update. Sold the K&N, preparing to get a Takeda.

The AFE Dry Pro S filter on the Takeda filters much better than the K&N.

Not to mention less time involved in cleaning, NO OILING, and NO POSSIBILITY OF MESSING UP MAF SENSOR FROM OIL!

[Spinnetti]

If it makes you feel good, great, but the intake is engineered for the needs of the engine. There is no street benefit whatsoever that will make any difference in real world use. If you put headers on too, bump up the timing, have a nearly open exhaust, up the fuel pressure to compensate, then maybe, but probably not. I run more or less stock intake on my race car (except I pull air through the corner light, but otherwise stock).

[LEX-SV]

Other than the placebo effect from the extra noise...

[reyoasian]

FSport/JoeZ.....guaranteed 5WHP ;)

[LEX-SV]

Wow, 5WHP, now there's a guarantee that will never be followed-up on. Too small to notice or feel, too small of a difference when compared to production variations of the stock ISx50 engines, a guarantee a MBA can love because potential liability is $0.

[reyoasian]

hahaha

that's why i use k&n and now takeda

i think the placebo effect from the sound is greater than the actual 5whp hahaha

[LEX-SV]

Good point, it's only money. :) And for the impact on sound effects, it's not that expensive.