ROTA_MOTION

....Right gentlemen,let's cut the crap and be realistic...

!) we bought a turbo series 4.
2) probably because we saw them on Gran Turismo.
3) we can't get 900bhp by winning a few races in real life.
4) but they look the business..
5) ....and we feel sooooo good every time someone walks
past and says "look...a ROTARY!!"....
6) but we don't tell anyone that they are not really that fast as standard......
7) most of us are not millionnaires and have saved every cent to get the car of our dreams.
8) so what can we do to get a few more horses out of the beast without costing us anymore of our hard earned bucks, and not risking our pride and joy being blown up.....

.........so........realistically......what's the cheapest way to more and better air flow.....can we use a bleed valve safely and effectively, and if so, how do we plumb it in....who out there has dyno results to prove that water spray CAN make a difference on the standard intercooler....and is 10psi or 14psi the SAFE limit for boost on a standard 13b turbo....and where do you measure a SAFE level of boost from, is it the pressure at the plenum or just after the turbo....does a cone(pod) filter give more gains over a performance panel filter replacement or just more noise....

.....sorry, maybe too many questions for a single thread, but I hope that there are other proud owners around who also want to know if THE TRUTH IS OUT THERE.......

FC3AZ

I would recommend downpipe, midpipe, and catback. Get an intake to go with that. If you get a fuel cut defencer, you might push to much boost for the amount of fuel you have stock. So an upgrade of fuel components is necessary. It's a non-stop lego building block type situation, just keeps stacking and stacking. You are gonna love that TII though. I love my N/A, and you have like 30hp on me.

RexSe7en

well first of all I would say put on a cone, and take off the stock airbox. Also you can do things like that throttle body mod, gut the cats, port the intake manifold, match port the throttle body. Take off all emissions, take off a/c and p/s. electric fan (costs like $20) and then obvious stuff like weight reduction and all that stuff, but that doesn't ad hp, just quicker. But anyways theres a start. You can search for all these things, and you will get in depth instructions. Good luck man

pvt.Cowboy

Kind of off subject but a friend of mine with a turbo car plumbed his NOS to purge onto his intercooler before he starts, he thinks it's good for a few short lived ponies..

TriTurboGen3 RX-7

very intresting idea, Nitrous to the Intercooler, but since it not regularly done, i would have to assume there's something about that in one way or another will hurt your car.

HuggyBear

all ur doing is cooling the air going through the IC.

1. its alot safer than shooting N2O into your engine
2. i doubt the temp of the N2O is going to crack ur IC
3. its worth a few HP depending on how much it cools the air.

anyone know just how much a setup like this will cool ur intake? and what HP that translates to?

kristopher_d

probably less than using it as designed.

Supermac 7

With a full exhaust and intake, you can beat 90% of the cars on the street, it's more than enough to whoop up on the mustangs and camaros . this is with a turbo.

With an N/A ( i absolutely loved mine), its a car that you dont want to mess with in the corners. it has this hardcore, lightweight feeling that is hard to get with the turbo cars.

They are two different animals, both a blast to own.

Jameson

Sonic

Better to just upgrade the computer. FCD are a waste of money if you ask me. That function can be done the same time as the rest of the computer upgrades.

Sonic

In my opinion I would say the stock airbox is better than a cone sitting there sucking in hot engine bay air.

A quick intake thing to do would be to get some foam type stuff (like HKS uses in their intakes) and cut that to size to fit in the air box. That's cheap and easy. I think the K&N drop in's are a big fat waste of money too. This set up will allow a lot more flow over the stock paper filter. The stock intake is not that bad. Just a paper filter being a big restriction.

I'd say the only thing you would gain with a cone/adapter would be sound. :shrug:

speedjunky

iTrader: (1)

The reason you don't spray in your intercooler it turns it in to a bomb. The one thing you are missing is a little bity spark.

Sonic

Nitrious Express (I think it's them) sell a kit that runs N20 around in a tube (that make sence?). You put this ring/tube around your intercooler and it just cools it. The entire N20 system is for cooling only. And 100% legal racing. You are not injecting it.....


As for the question of this topic. W/ an older car like this my first concern would be to get it running/driving right. Both Prothane and Energy Suspension make full suspension bushing kits. I'd do that, springs/struts, toe-steer eliminators. This will make your car a lot safer too.

And then basic bolt ons, downpipe, exhuast, maybe a boost and EGT gauge.

BlackRx7

where are you guys getting this nitrous from, he it talking about water injection that I've heard is very effective, where can you get or make a water injection system.........

rotard

I can't see how the nitrous in the intercooler thing could be a "bomb", unless your car is already on fire.

Nitrous doesn't burn. It's N2O -- the nitrogen falls off when it gets hot, so you end up with some extra oxygen to help along combustion.

emagdnim

You dick! I thought you'd mail me some free HP!

TheAnalogKiddd

iTrader: (2)

so you want free/cheap horsepower without risking reliability.. hmm..

you could always just buy/make a boost controller and crank that up. cheap but not safe.

and there's lots of nickel and dime mods that can make a little to moderate difference and not pose a serious risk.

but if you want to do it right you're gonna have to spend a little. People are saying intake and full exhaust. From what I've learned this might not be such a good idea on a stock TII with a good turbo. Here's what I'd do..

(this applies to an s4)

get a downpipe and a cone intake(or do the tid mod), it's fairly cheap and still safe. hopefully it'll put you around 8 psi where your stock fuel system is good. fcd might be needed but should be safe at this boost.

or

save up a little money ($1300-$1500). buy a full racing beat exhaust. leave the stock airbox, maybe a K&N filter. on a good turbo it should put you around 11-12 psi on a non-ported wastegate. I would not go above 11-12 psi on the stock turbo because after that it doesn't put out anymore air than it does at 11-12, it just gets hotter and could damage it. THEN upgrade your fuel pump, a walbro 255 is great(and cheap) AND either:

get an ecu reprogram for your mods for about $300 and you're done, safe and fast.

or

get an s-afc and time on a dyno, ~$500 combined?

The ecu reprogram will get rid of fuel cut(no need for an fcd) and give you a safe fuel map for your mods. However, the more expensive option will give you more flexibility.. that is if you were to do anymore mods than you could adjust your fuel whereas the ecu would pretty much be useless, and dangerous.

At this point, if you want to do further mods, I would look into suspension. But if you want more power, you can get a cone intake, do the TID mod or anything else that frees the flow. **port your wastegate to keep the boost down. buy/make a boost controller if you want to crank it back up some. A free flowing exhaust and intake is great, but you've got to keep boost and fuel in mind. It's great for an upgraded turbo, but that's out of my territory.


Hope this helps.

rotarygod

iTrader: (1)

Just my .02 on this topic but here goes. The 1st question was "whats the cheapest way to more and better airflow?". Simple. Free up the intake and exhaust. A cone filter is worthless if there is an air flow meter restricting the air behind it. However, a neat little trick which does more for turbo response is to move the afm to after the turbo instead of before it. Now put a cone on it and build a cold air box around it. The afm will still work fine since the same amount of air is moving through it just under pressure rather than vacuum. Next move your stock intercooler to the front of the car. It doesn't matter if it the same one as long as it receives cold air from the front. The aluminum elbow that goes on the front of the throttle body, straighten it out. It is killer on airflow and is a poor design. Do the TB mod. Again more of a response thing. Free up the exhaust so your turbo will spool faster. Add an fcd. This car is not a 3rd gen. The computer will compensate for the increase in boost pressure. Port your wastegate to reduce creep. Get a boost controller just don't go above about 10 or 11 psi on the stock turbo since the air gets heated up too much from too small of a compressor. A bleed valve may increase boost pressure but it doesn't modify the boost curve like a controller. Get a 3rd gen fuel pump for added fuel and maybe even a rising rate fuel pressure regulator. These mods should be good for around stock 3rd gen speeds. My best friends car is very similar to this and it is quite quick. Just my input though. I'm sure some will disagree, just be nice if you do.

Fred

ROTA_MOTION

all of these mods are good. i think of an engine as a big air pump. the more air that you can get in and out the better.
i dont like the look of that sharp bend before the throttle body so that has to go, it must harm the air flow somewhat, dose anyone make a piece to replace it ?.

scathcart

I purge my 6-AN nitrous feed line through my stock intercooler before I make any kind of nitrous run. A purge valve is a great nitrous accessory, and the fact that I could use it to cool my IC was a bonus.

I mocked up a spray bar and hooked it up underneath the intercooler so it sprays out of the scoop. Looks pretty sweet.

I dunno what its worth... 5 hp maybe? It's kinda hard to gauge since at the time of use I am usually around 450 horsepower. I suppose I should just purge it sometime and see what its worth... maybe next time I dyno?

Nitrous comes out at -127 degrees fahrenheit. Sometimes the intercooler frosts... I'm curious to see what wopuld happen if I soaked the IC with water first, and then purged. The water would freeze, but thee wouldn't be enough to crack the core, and the water would stay frozen and cool the air for the run just a little bit longer.

Anyhoo, to sum it all up: I run it, it will add horsepower, but I am yet to find you how much.

NZConvertible

A restriction is a restriction no matter where you put it, so how would this mod help turbo response? Restrictions after the turbo have as much affect on response as those before it.
Also, the AFM should never be mounted between the turbo and the IC, as the turbo outlet temp is far too high. If you’re going to relocate it, it must be after the IC. They don’t modify the boost curve as much as an EBC, but they definitely do change it. This is because of the restriction in the wastegate line needed to make a bleeder work. This slightly delays the actuator’s response, bringing boost up a bit quicker. Was I nice enough?

rotarygod

iTrader: (1)

You are correct...the afm should go after the ic. Forgot to mention that one.

rotarygod

iTrader: (1)

Grab a cold beverege, sit back and relax. This could take a while to write and probably will so I apologize nowForgot to address the afm location. To say that a restriction will have just as much affect before a turbo as it does after it is both right and wrong. A restriction is a restriction. True, when you are talking about horsepower available. I am talking about turbo response. I will explain in a minute but first I will give an example of something similar we do to our cars to help illustrate the point. Why do the tb mod if there is no hp gain? Easy, it effects throttle response. There is no horsepower to be gained from removing the double throttle plates. If these plates were located farther down the intake stream they would have no effect on the throttle response. The same principle applies to the location of the afm in relation to the turbo. With the afm less than a foot in front of the turbo, the turbo is working hard to suck through it. By moving it far away and after, the turbo almost doesn't know it is there anymore. The turbo is now free to take in air as fast as it can. Ah yes, I can hear it now, but the afm is still a restriction in the line. So what?! It is so far away that the natural springiness and compressibility of the air have almost masked its existence. You don't honestly think air is going to have a hard time flowing through it after it sees a horrible flow device like an intercooler do you? It takes time for air to flow through the intake system. By the time the air reaches the afm from the turbo, the turbo has already started to spool faster than it would if the afm was in front of it. By this time there is greater pressure available to overcome any shortcomings in the afms restriction. Like I said total horsepower will not be affected but the response time will. In fact it is quite logical to assume that since the turbo is now free to spool faster, then there is now more usable horsepower availabe throughout the rpm range even the though the total peak may be no more. This concept takes a small amount of comprehension but makes perfect sense after a good deal of thought. NZConvertible in absolutely no way am I flaming you or insulting you. You obviously know what you are talking about and seem quite intelligent. I don't want you to take any offense to this. Your point is well made on the bleed valve. That was more or less what I meant and yes you were nice enough

On a side note but still pertaining to the restriction thing, my '88 has a custom made aluminum intake manifold which I designed and built. More details on it at another time. There is a central plenum but the throttlebody (75mm Mustang unit) is not mounted directly on it. It is mounted downstream of the plenum about 10 inches or so. The turbulence from the throttleplate has dissipated by the time air reaches the plenum and cosequently the air disperses throughout the plenum more efficiently. But the distance that the 3" pipe makes between the tb and plenum does not account for any of the plenum volume. The plenum is only the chamber that the runners begin at. It doesn't matter whether or not there is a "door" on that "room" or not or even if its open or closed. When the car is at wot the location of the tb seems to disappear from the engines point of view and no longer serves as a "hostile" restriction. Same thing that applies to the afm. Just thought the info. might be pertinent. Sorry for the long post guys.

Fred

ROTA_MOTION

has anyone actually put there afm after the ic? i know some afm's have a barometric pressuer sensor in them? would that effect it? what about when your at full noise running 15 psi the engine can only take so much air at any one time, so the air slows down and backs up keeping the pressure, when it gets to the afm it will see a reduction in air speed and the flap will close a bit , in turn leaning out, think if it lit water running down a gutter, put a small dam in the way eg ports and the water backs up ,

just my .02 cents, but im probably wrong, so shoot me down.

95R2-89TII Ground Zero

MP, DP, CB, and make sure to get an intake. With that you will breathe a bit easier than the stock setup. Then I might suggest a port and then removing the air pump. While you are doing that, you might as well transform to the manual rack from PS.

rotarygod

iTrader: (1)

Many people have put their afms after the ic. Its not something I came up with. There will be no problem with air backing up after a certain point after it gets to the afm. The same amount of air is still passing through it no matter where it is. This hits back to the restriction is still a restriction thing. In this case it is only on a horsepower basis. If you can't boost above 15 psi with the afm after the ic then you can't with it in front of the turbo either. The goal of moving it is to mask its restrictive effect on turbo lag. It is true that there is a reduction in air speed at the afm. It was there with the afm in the stock location too. There is also another reduction in air speed at the ic and the throttlebody as well. In using your own example of water in a gutter. Does any more or less water flow through the gutter if the dam is at the top or bottom of the gutter? Answer is a surprising yes but only to a point. There is always an exception to every rule. This may serve to bring up some more questions so I may have to clarify later if this is incomprehensible. If the dam is at the bottom then there is much greater water velocity and pressure when it gets there. This increase in pressure will help more water flow through it faster than if the plug were at the top where there is no aid in pressure. If there was a turbo at the beginning of the gutter it would have had sufficient time to create at least some boost in the system before the water gets to the dam. This is just an example I know you can't compress water but you can pressurize it. Obviously this is a very short amount of time so not too much will be gained. Any is the goal. This pressurized air now has more force with which to interact upon the restriction. Basically you have given the air more leverage on the afm door with which to do the same job. If the dam was at the top of the gutter right before the turbo there is no leverage and consequently slower response even though the total restriction has not changed. It is a little hard to use water as an example even thought both air and water are technically fluids. The gutter example with water really only applies to pressure being equal and not under a boost situation like air would be. Since air is compressible there is a springiness which water does not have and it therefore doesn't quite work the same under boost situations. Water is a great example if things were only being pulled through as in a naturally aspirated situation. By carefully choosing locations for restricions (if you absolutely have to have them) you can mask their hostile effects on airflow and various component responses. I hope this helps clarify some things and didn't send anyones brains into overload.

Fred