Nissan 370Z Tech Forums banner

1 - 17 of 17 Posts

·
Registered
Joined
·
16,332 Posts
Discussion Starter #1
Will there be any gains had if you add Ram-Air to a supercharger setup? It seems the superchargers available are sucking in hot air from the engine bay.

Offsetting any cold air intake, Boost pressurizes the air heating it up, so i am not sure what gains if any may be had.

Thoughts>?
 

·
Premium Member
Joined
·
35,304 Posts
I thought I read something once about how advantageous cold air into the engine is for HP. The denser air allows for more compression (?) and oxygen to be ignited inside. That's the basic understanding I have of that concept. Correct me if I'm wrong, please.

All I know is hot air is no good being forced into the intake, and if you say the s/c is doing that then a ram air positioned under the front lip or inside the grill would be one solution. But then again, isn't that the same position one of the after market intakes is at?
 

·
Premium Member
Joined
·
5,911 Posts
Originally posted by SmoothZ@Aug 14 2004, 09:30 PM
I thought I read something once about how advantageous cold air into the engine is for HP.  The denser air allows for more compression (?) and oxygen to be ignited inside.  That's the basic understanding I have of that concept.  Correct me if I'm wrong, please.

More air = more gas = more compression
 

·
Registered
Joined
·
16,332 Posts
Discussion Starter #4
when you compress air it heats up, when you decompress it it cools down.

i think i will be looking into a ram air-type setup, and i will be going S/C later this year..
 

·
Premium Member
Joined
·
35,304 Posts
Originally posted by DiRN@Aug 14 2004, 08:55 PM
More air = more gas = more compression

So denser air = more air because there is 'more' of it per cubic inch. More volume...
 

·
Registered
Joined
·
16,332 Posts
Discussion Starter #6
yes, i guess my question is , would ram-air do anything for forced induction.

All the turbo setups and superchargers seem to have the intake filters right in the engine bay, which is far from cold air. My assumption is that the compression of the air would neglect any benefit of a cold air intake or ram air setup. but it wouldnt hurt to try.
 

·
Registered
Joined
·
230 Posts
I would think if you could get any cool air into the intakes it would be a plus. If you've noticed on the Stillen body kit the front bumper has an intake inlet so the concept would have to be correct, whether it's F/I or N/A. I had a magazine that introduced some new body kits that I would think would be perfect for a TTZ. It had the same concept as the Stillen only it had one on each side. Now it was technically not a RAM air but more cooler air from the outside would enter the engine bay much easier. I'm sure you could find some way to harness that direct air flow coming in thru the front bumper with some sort of duct work that would essentially be RAM air. I may be way off base.

Here's a pic:
 

·
Registered
Joined
·
1,493 Posts
All this is true, except I thought someone told me one time that condensed air is cooler, that it was a basic physical property of almost all matter, that, when condensed, it becomes cooler. I could be wrong on that one, though.

However, I know the reverse is true (except for freezing water) the colder you make something, the more dense it is. For instance, inflate a balloon, measure the circumference. Then put it in the fridge for 10 minutes, then measure it again. There will be a considerable difference.

Anyway, what I really wanted to say is this...the reason RamAir works so well is 1. You are getting cooler air "forced" directly into the intake. Normally, not only is the inside the engine compartment hot, but it's stagnant. RamAir is coming in at (or about) the same speed as however fast you are going, improving air flow, 2. Often, in RamAir there will be some sort of funnel before the intake. This, basically, takes the amount of air in a large opening and crams it into a smaller opening, esentially condensing it, increasing air pressure, and making it possible to get more air into the chambers...and as we all know more air = more potectial HP.

Of course, it, obviously, won't a huge difference, prob 3HP (if you're lucky) or less on an N/A car, but it definately helps.
 

·
Registered
Joined
·
16,332 Posts
Discussion Starter #9
actually, when you pressurize air it gets hot!

Example: CO2 Cartridge.. if you let the air out it "de-pressurizes" and frost develops on the cartridge. (cold!)
 

·
Registered
Joined
·
1,493 Posts
Ah yes, good point.
 

·
Registered
Joined
·
31 Posts
In theory it seems like it would work great. However i would really have to ask the question, why, if this does work, would an company that makes superchargers not use this idea. I wonder if there is some sort of issue with the S/C already taking in as much air as possible, hot or cold. You never know, maybe the companies just say well this product is good enough, even though Ram-Air would make it better. It's also possible it might be a cost issue, space issue, who knows. This is one to look more into.
 

·
Registered
Joined
·
1,493 Posts
I suppose it's possible that there could be some issue with it, although I can't imagine what that would be. Never heard of any issues with using RamAir in conjunction with FI. More likely it's a combination of the latter things you said.
 

·
Registered
Joined
·
16,332 Posts
Discussion Starter #13
I think it it would just add cost to the FI system.. But i do think colder air is always a good thing... im just curious as to HOW MUCH it is a benefit...

I also know that RAM AIR cannot really be dyno-measured.. only at speed will the benefits be fully had...

As pistons compress the air.. the air gets hot.. if it gets too hot, there is pre-ignition.. or the fuel-air mixture can ignite before the sparkplug sparks...

Superchargers and turbos compress the air.. that is one reason they get so **** hot..
 

·
Registered
Joined
·
66 Posts
I would think if you could get any cool air into the intakes it would be a plus. If you've noticed on the Stillen body kit the front bumper has an intake inlet so the concept would have to be correct, whether it's F/I or N/A. I had a magazine that introduced some new body kits that I would think would be perfect for a TTZ. It had the same concept as the Stillen only it had one on each side. Now it was technically not a RAM air but more cooler air from the outside would enter the engine bay much easier. I'm sure you could find some way to harness that direct air flow coming in thru the front bumper with some sort of duct work that would essentially be RAM air. I may be way off base. :helpsmilie:
Here's a pic:
ive looked all over for that bumper on that orange Z can someone please tell me were i can buy
the darn thing thannkz sooo much !!!
 

·
Registered
Joined
·
6,899 Posts
ive looked all over for that bumper on that orange Z can someone please tell me were i can buy
the darn thing thannkz sooo much !!!
that bumper is a modified nismo bumper (or, it looks exactly like one). :)
 

·
Registered
Joined
·
85 Posts
Detonation with FI is the result of the air:fuel charge getting too hot in the cylinder. A cooler charge means that you can use higher boost pressures or more timing advance/less timing retard - that means more potential power. "Ram Air" is pretty pointless, as even a really good scoop will only produce a fraction of a psi at 100 mph. What matters is getting the coolest charge possible to the engine - the cooler the air is to start, the cooler it will be once it gets to the cylinder.

Intercoolers do the same thing, working after the compressor so that the charge is forced through it. But there is a pressure drop through the intercooler, loosing boost. Starting with cold air is a great way to go, but good scoops cost money and often look bag. Most FI kits are pretty basic really, so that an average owner/shop can install it. More parts cost more money - it's realy a matter of economics.
 

·
Registered
Joined
·
5,719 Posts
Which explains why basic S/C kits don't come with intercoolers.

I would never run any air compression setup without some kind of intake charge cooling (whether it be a heat exchanger or methanol / water injection).

A cold air intake does help on FI. While I was shopping for a car I almost bought a S15 200SX, and the first thing Silvia owners do is pull out the stock airbox and run a boxed pod filter and a cold air pipe.
 
1 - 17 of 17 Posts
Top