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-   -   intercooler on na car? (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/intercooler-na-car-942653/)

canonize-ryda 02-19-11 04:27 PM

intercooler on na car?
 
would there be any benefits to adding an inline intercooler for the cold air intake, so the air going in is infast cool air not just air from outside?

texFCturboII 02-19-11 04:50 PM

No.


-Ted

Donovan N. 02-19-11 04:55 PM

i heard somewhere that optimum air temp for a motor was around 100 degrees, so in my opinion it wouldn't really have an affect. I think of it this way if it helped to have cold air every bodys cars would be making way more power in the winter than in the summer.

SpeedOfLife 02-19-11 05:13 PM


Originally Posted by Donovan N. (Post 10478138)
i heard somewhere that optimum air temp for a motor was around 100 degrees

Whoever told you that was talking out of their ass. I say that for a host of reasons, but chiefly because of how vastly different all the different engines out there are managed with regard to fuel, spark, intake temperature, knock, humidity... my god the list goes on.

Brodie121 02-19-11 05:23 PM

:facepalm:

canonize-ryda 02-19-11 05:24 PM

so then was ted right? i mean its such a big deal to get a cold air box. i mean why not just route in an intercooler to lower the outside air further and make it better, and as regard to the winter and more power thing i feel a bonno effect from it anyways. lol

Evil Aviator 02-19-11 05:33 PM


Originally Posted by canonize-ryda (Post 10478092)
would there be any benefits to adding an inline intercooler for the cold air intake, so the air going in is infast cool air not just air from outside?

It would work if it could be designed with the following criteria:
- Air is refrigerated below the ambient temperature
- Any restriction caused by the additional cooler piping does not cause a pressure restriction that negates the value of the cooler air.
- The weight of the system does not negate the performance gain.
- The refrigeration method is such that it does not consume any engine power when the car is accelerating. For example, a pre-charged system such as liquid oxygen, or a system that charges during cruise.

It is possible, but not practical on a regular street car, and probably not legal for a race car.


Originally Posted by Donovan N. (Post 10478138)
i heard somewhere that optimum air temp for a motor was around 100 degrees, so in my opinion it wouldn't really have an affect. I think of it this way if it helped to have cold air every bodys cars would be making way more power in the winter than in the summer.

Confirmed that the 100F myth is not true, and confirmed true that everybody's car does in fact make more power in the winter than in the summer. However, it is not way more power, as the performance advantages of colder air are hugely exaggerated by companies who are trying to sell you their overpriced intake products.

There are some conditions in which the air can be so cold that the fuel has problems vaporizing, but this is usually only a problem under sub-freezing conditions.

clokker 02-19-11 05:45 PM

The colder, denser air of winter is indeed great for the intake, but at least some of the benefit is offset by the fact that the very same cold,dense air is harder for the body to punch through.
No free lunches at the "cold air buffet".

lastfc3 02-19-11 07:16 PM

:Wconfused: would you pipe in a filter on the inlet of intercooler, would it draw in enough air to start the car

FC3S_nataku 02-19-11 07:21 PM

What about a small meth injection deal? That would not cause loss at cruising and could be set to come one at 100% load. Something I have always wanted to try was to make a t2 hood into some kind of intake like those seen on the Mach 1 mustangs.

SpeedOfLife 02-19-11 07:36 PM


Originally Posted by canonize-ryda (Post 10478180)
so then was ted right? i mean its such a big deal to get a cold air box. i mean why not just route in an intercooler to lower the outside air further and make it better, and as regard to the winter and more power thing i feel a bonno effect from it anyways. lol

First of all, Ted is almost always right. Second of all, how do you think an intercooler works? The biggest reason it does anything of value is because whatever the ambient temp is, the turbocharger is going to make it hotter when it goes through the compressor turbine, and raising the intake charge pressure heats it up even more, and the only, ONLY way to cool something is to rub something against it that's at a lower temperature so it will give its heat away. If you did this with a non-turbo motor you'd be taking in ambient temp air, possibly plus only a few degrees due to heat soak in the intake and the fact that you may be drawing air from the engine bay, and then dragging the intake charge through an intercooler to try and bring the temp down with ambient air (at best). You cannot possibly bring the temp lower than ambient with an air-air intercooler unless you're using a trick like evaporating something on the intercooler, and chilling a liquid around the intercooler will not last long unless you're constantly refrigerating the liquid, which is a terribly inefficient way.

If you want to make significantly more power with little to none for engine mods on a non-turbo car: nitrous. But don't just throw a bottle on there and throttle it, do some research. As for me, I'll keep my turbo (rather, I'm slowing gathering parts to have a BNR stage 4 S5 turbo built...).

Slow Rotor 02-19-11 07:37 PM

I think he is refering to putting a standard air - air intercooler in place. In short the restriction of it would cancel out the cooling effect.

SpeedOfLife 02-19-11 07:40 PM


Originally Posted by lastfc3 (Post 10478288)
:Wconfused: would you pipe in a filter on the inlet of intercooler, would it draw in enough air to start the car

It probably would, but of course it would depend mostly on the resistance the intercooler created. I would not be surprised if it would practically suffocate the motor at high RPM WOT though.



Originally Posted by clokker (Post 10478198)
The colder, denser air of winter is indeed great for the intake, but at least some of the benefit is offset by the fact that the very same cold,dense air is harder for the body to punch through.
No free lunches at the "cold air buffet".

I hope you were joking :lol: Surely you realize that's damn near negligible.

Evil Aviator 02-19-11 08:26 PM


Originally Posted by FC3S_nataku (Post 10478293)
What about a small meth injection deal? That would not cause loss at cruising and could be set to come one at 100% load. Something I have always wanted to try was to make a t2 hood into some kind of intake like those seen on the Mach 1 mustangs.

Yes, some type of cooling injection would work, but it probably wouldn't be worth the trouble for the small performance gain. Nitrous oxide would offer way more performance for the same amount of trouble.

Just for reference, each 10F that the intake air is cooled will only yield about a 1.2% hp increase. Therefore, if you have a typical 13B NA engine, reducing the intake air temperature by a whopping 50F would only add about 9 hp. Big whoop-de-doo.

The stock T2 hood scoop is actually in a bad spot because it is mounted in a low pressure area. Sure, you could turn it into an intake, but an inlet at the front of the car or at the base of the windshield could take advantage of the slightly higher air pressure when the car is at top speed. If the car is intended to operate under 80mph (street cars or drifting), then the ram air pressure isn't really a factor.


Originally Posted by Slow Rotor (Post 10478325)
I think he is refering to putting a standard air - air intercooler in place. In short the restriction of it would cancel out the cooling effect.

Even if an air-air intercooler were 100% efficient, it would still only cool the air down to the ambient temperature. In other words, even a fantasy air-air intercooler would have zero performance effect if the engine is already getting ambient air.


Originally Posted by SpeedOfLife (Post 10478331)
I hope you were joking :lol: Surely you realize that's damn near negligible.

It does make a significant difference at high speed. Granted, that doesn't apply to most people on this forum, but in all fairness it is a correct statement. :D

K-Tune 02-19-11 08:55 PM

Get a huge intercooler and chop up your bumper to fit it...run the air filter piping back into the engine bay. It will be so awesome.

SpeedOfLife 02-19-11 09:06 PM


Originally Posted by Evil Aviator (Post 10478401)
It does make a significant difference at high speed. Granted, that doesn't apply to most people on this forum, but in all fairness it is a correct statement. :D

What kind of high speed are you talking, mach 4? :rofl: For a land speed record trial it might matter a little. How little I'm not sure, but how many high speed road races and drags are held below freezing temps? That's rhetorical, I am actually interested in knowing how much difference it would make at 250mph wind speed between 100*F and 50*F, to throw some numbers out there.

Roto_Racing 02-19-11 09:09 PM

just because its called a cold air intake does not mean it cools air
cold air intakes create a more direct rout to the throttle body and because of its smooth port like walls it "allowes the air to move easier".
i dont see how cold air in the engine would make a diffrence
turbos pump in regular air
and NOS just provides more oxigen
intercoolers help the turbo keep cool by cooling the hot air coming in
like a radiator cools hot water from the engine
if you want you can replace your filter with a block of dry ice if it does add horsepower let me know ive always wanted to try that

canonize-ryda 02-19-11 11:41 PM

lol so im convinced im wanna throw nitrous on it.... thanks guys lol

Carzy Driver 02-20-11 12:08 AM


Originally Posted by canonize-ryda (Post 10478180)

Originally Posted by texFCturboII (Post 10478125)
No.


-Ted

so then was ted right?

:lol::lol::lol:

DaBrkddy 02-20-11 12:21 AM

Oh dear. :facepalm:

Now we've created a monster that wants instant gratification.

...And then after he's out of this magical oxidizing gas he will go home crying to mommy because his bottle is empty... Or because his engine is blown.

clokker 02-20-11 08:39 AM


Originally Posted by SpeedOfLife (Post 10478464)
What kind of high speed are you talking, mach 4? :rofl: For a land speed record trial it might matter a little. How little I'm not sure, but how many high speed road races and drags are held below freezing temps? That's rhetorical, I am actually interested in knowing how much difference it would make at 250mph wind speed between 100*F and 50*F, to throw some numbers out there.

Air density (in which temp plays a rather large factor) is not a phenomonon that only comes into play at "record setting" speeds.
Pilots commonly factor it in to determine fuel load/range and even hypermilers pay attention as it can adversely affect their high mileage endeavours.

As ambient air cools and becomes denser it provides more combustible oxygen (which the engine enjoys) but simultaneously, it makes it more difficult for the body to slip through the atmosphere.
This is not speculation or theory, it's simple fact.

Hypermilers- not known for high speed antics- have charted the effect of air temp v. mileage and it's not "negligible" nor does it require high speed to demonstrate.

My original point was not to dispute the possible advantages of a passive "cold air intake", merely to point out that it's not a "free" gain.

It is commonly observed on this forum whenever a engine bay pic is posted that shows a filter clamped on the end of the MAF, that "heatsoak" is hurting performance.
People routinely go to great effort to block off the filter from radiator waste air and route "cold" air to it from the brake duct (or wherever).
This is touted as a performance mod.

My ambient air intake placed the filter in front of the rad, completely free from heat contamination, sucking down the "coldest" available air possible.
Switching between that setup and the more common (and simpler) filter on MAF arrangement lead to no noticeable changes in power delivery and fuel mileage.

So, if one wants to argue that "cold air" has but a negligible effect on the car's aerodynamics, you'll have to start by proving that "cold" air actually increases the engine output as well.

(Again, this is all predicated on passive intakes...not turbo/supercharged and not artificially cooled intake tract, meth/water injection)

canonize-ryda 02-20-11 10:27 AM

well would it hurt to add a switch for a slow nitrous leak into the intake(so no shot of nitrous just some slow injection) and i would just go buy another bottle i wouldnt cry i swear. and im not worried bout blown engine, since if it did blow i would rebuild with a new port job(so im awaiting lol) yea i may be power hungry but comon what na owner isnt, and id only be doing short runs with nitrous, so any opinions?

jjwalker 02-20-11 10:34 AM

No nitrous...no no no.

Total waste. Not only will you probably toast your current motor (and you said you dont care) you'll probably toast the new one too.

I'd say if you want more power but do not want to crack the keg apart yet, invest your money into headers and full exhaust. That is the real HP ticket on an NA there, without cracking the keg open of course.

Aaron Cake 02-20-11 10:50 AM


Originally Posted by canonize-ryda (Post 10479037)
well would it hurt to add a switch for a slow nitrous leak into the intake(so no shot of nitrous just some slow injection) and i would just go buy another bottle i wouldnt cry i swear. and im not worried bout blown engine, since if it did blow i would rebuild with a new port job(so im awaiting lol) yea i may be power hungry but comon what na owner isnt, and id only be doing short runs with nitrous, so any opinions?

Learn about nitrous systems via a few Google searches. Look up "nitrous basics", "nitrous fogger", "direct port nitrous" and then continue researching based on stuff you turn up. Nitrous isn't the big black box that many people will have you believe. There are even links in the 2nd gen FAQ with information on installing and tuning a nitrous system.

To really bake your noodle, nitrous or other gas capable of super cooling (CO2, etc.) is sometimes used to spray down intake plumbing and intercoolers to lower intake temps past what would normally be possible with simple air cooling.

canonize-ryda 02-20-11 11:57 AM

yea all i need for full exhuast is a set of headers, witch im shure will take out the precat i still have up there, also if i have stock ecu hwo do i tune it with the full exhuast and intake and varies other goodies? or does the stock ecu tuning do ok with all these mods?


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