bewst pewp

Ok before I post the question I completely understand that a front mount intercooler, even an ebay knock-off front mount intercooler set-up would free-up several ponies compared to a fectory s13 silvia side-mount.

With that said the question at hand is at what point does the stock s13 side-mount intercooler begin restricting horsepower from the breathability or the sr20?

I never noticed any difference from when I had a stock s13 sr20det at 12psi on the t25 with a fmic in my s14 to what I know have which is another stock s13 sr20det at 12psi on the t25 with the factory side-mount. To be totally honest it feels like I have alot less lag with the side-mount than I did with the fmic.

I'm about to upgrade to the oem bolt-on style gt2871r .64 ar on a s13 sr20det which is being rebuilt with forged internals (rebuild is necessary for the engine itself not for the turbo set-up) and was debating on if that would really hold back very many ponies and if it would possibly seem to have less lag since the smic piping is only maybe and inch and a half to two inches I figured it would possibly be able to pressurize the piping and the intercooler faster and decrease on some lag. But the the heat soaking from the turbo would come into play.

So the questions is does anyone actually know when the factory smic begins to severly restrict horsepower?

bewst pewp

I actually just got an email back from enthalpy on the subject statign they are only effective to around 200whp. After that they can cause the intake air temps to raise enough to cause detonation.

ship2236

Good fact to know
thanks

__________________

20 til 3

FYI the s15 had a much larger factory SMIC

buentellomma

i destroyed my 2nd sr20 using a side mount running 12psi in the summer, the 4th piston was missing some pieces and the rings were melted. im now running a retro fitted srt4 intercooler in a mid mounted setup and its a very noticeable difference even at 7psi. ditch the side mount man

hsitko

You destroyed engine internals on cyl. #4 with a side mount huh? Well if thats not a reason to put an intercooler in the path of every rock and lug nut flying down the road at greater than 60mph i dont know what is! The honest truth is, if you have a side mount THAT IS DUCTED PROPERLY, of a decent size and not mounted behind your radiator it will function great until you reach a certain boost or hp level. They are very nice for certain power levels. They are typically not huge and due to that have a result of making the turbo spool faster (although nominal). They dont catch road debris which can damage the fins and tubes or plates rendering your intercooler useless. People who run front mounts with no mesh in front of them should be constantly straightening their fins. It gets very easy to loose 30% or more of your fin area very quickly. Pick an intercooler for your boost/power level not because someone said they melted a piston with a stock mount because they were likely not monitoring intake air temps, possibly running the intercooler unducted, and went lean.

fliprayzin240sx

WHAT THE FUCK ARE BABBLING ABOUT? Side mounts suck for the simple fact that any psi beyond stock boost on a stock T-25, they are stop being efficient at cooling down your charged air. Stock S15 sidemount (thicker than S13 or S14s) are efficient up to 10 psi. There was an article done a couple years back where somebody measured the air temp before and after the stock sidemount and it didnt change much.

Thats how people blow their fucking engines, hotter, compressed air into the engine, with no fuel tuning = hello detonationville.

__________________

If you think Zilvia has too many assholes...
CLICK HERE!!!

buentellomma

exactly what happened to mine 6 years ago, i learned my lesson. the side mount is nice if your going to keep it stock.

hsitko

Simple facts here.
1) You dont need to go overkill on the intercooler.
2) If you melted an engine because of an intercooler, you did not research your modifications enough. And likely dont understand just how hard you are pushing your engine. If you are unsure you should have monitored your air temps as that would have been a direct indication of the intercoolers efficency at your chosen boost level.

Its obvious by your hostile reaction that you misunderstood what i was trying to say. Which is, the stock mount intercooler is fine for certain applications. If you are running the stock (small) turbo a big front mount has some negative consequences at stock boost levels. Spool time increases and the intercooler its self is subject to more abuse. For the amount of money you would spend on a front mount you could purchase something of much greater value for cooling intake charge and lowering ccp (combustion chamber pressure). Alcohol injection. Many companies produce systems that are very easy to spec out, install and use. If you use water you will dramatically lower ccp and have the benefit of steam cleaning engine parts. Water has a great latent heat effect which cools intake air charge very well. If you use alcolol you could actually ice over your intake manifold with the stock mount intercooler (yes thats right, ice over). You could actually run no intercooler if you wanted to. Personally i wouldnt just in case a component failed. But you could. With AEM, Devils Own, Cooling mist, FJO and several other companies making these kits with entry costs around $300 it is money much better spent. I come from the world of rotaries. My main interest is my 1993 fd rx7.

I'm very familiar with ccp. A stock rotary 13b-rew is 1.3L with combustion events happening 2x that of a 4 stroke engine so we consider it 2.6L.

Stock it produces 255 flywheel hp divided by 159 cubic inches equals 1.6 hp per cubic inch!

A stock s13 red or black top is 121 cubic inches or 2.0L. In stock trim it produces 202 flywheel hp. (I picked the s13 power number as its what most people run.) Which comes to 1.6 hp per cubic inch! The same as the 13b-rew. That is a lot stock! Especially since the 13b-rew is .6L bigger for this comparison.

the 2009 Corvette LS7 ZO6 motor is:

hand built by Chev.

has:

titanium valves and rods
6 bolt main bearing caps
dry sump lubrication system
and every bit of engineering Chev could throw at it.

and it makes 1.18 horsepower per cubic inch!

the 2009 Dodge Viper SRT10 makes 1.17 hp per cu inch.

both 2 valve motors. 4 valve motors make 27% more hp & torque...

more air makes more ponies.

the 2009 4 valve Lambo Murcielago ($440K) makes 1.59 hp per cu inch

o k let's add more air...

enter the 2009 Corvette ZR1
supercharged and approx 40 K more than the ZO6... 1.69 hp per cu inch.

how about a 4 valve twin turbo 2009 AMG Merc SL65 AMG?

1.81 hp per cu inch.

each of the above mega price/mega hp offerings could have been tuned up for more hp but the manufacturer made a decision as to where to say NO to more power with a consideration to engine reliability.

normally aspirated piston engines:

it looks like the balance point is around 1.18 hp per cubic inch.

forced induction:

around 1.75 hp per cu inch. (the 27% differntial between 2 valve and 4 valve is in-operative on force fed motors for obvious reasons.) Now remember what the sr20det is stock. 1.6 hp per cu inch. Pretty close.

My FD makes 400rwhp which is 460 crank hp. 460 divided by 159 cu inches (or 2.6 liters) is 2.89hp per cubic inch!!!!

For an sr20det to get to that 2.89 hp per cubic inch mark it only needs to get to 349 flywheel hp! That isnt a whole lot of total hp! But that is a ton of hp per cubic inch. That is seriously pushing it on just about any engine. We are talking serious drops in longevity and reliability as a result. That is a truly massive amount of hp per cubic inch with just over 300 hp to the wheels.

gasoline, any gasoline including racegas, auto-ignites at a mere 495 F. as we raise hp levels we are moving closer to auto ignition/knock/breaking.
alcohol, (methanol, ethanol and isopropyl) ignite at 858 degrees F! If you have an AI system like FJO's and a stand alone ecu, you can actually tune 20% of the fuel out of your maps and replace it with methanol. Which means more advanced ignition timing, more boost and more power!

Combustion Chamber Pressure.

torque is a direct product of CCP and when related to RPM determines HP.

CCP correlates directly to heat.

The best way to address the issue of high ccp and heat is with AI. There are many benefits and the systems arent overly expensive or difficult to set up. The benefit of the injectant you choose is based on what kind of latent heat effect you want. The highest latent heat effect comes from water. The only issue is that water is not a fuel. Here is a table of potential injectants and their latent heat effects taken from engineeringtoolbox Engineering ToolBox

Product Latent Heat of Evaporation
(kJ/kg) (Btu/lb)
Acetone 518 223
Alcohol 896 385
Alcohol, ethyl (ethanol) 846 364
Alcohol, methyl (methanol) 1100 473
Alcohol, propyl 779 340
Benzene 390 168
Heptane 318 137
Hexane 365 157
Kerosene 251 108
Propane 428 184
Toluene 351 151
Water 2257 970

Pick what ever intercooler you want but remember that no matter what intercooler you pick you wont be lowering combustion chamber temperatures very much in comparison to AI. Of course we know that the primary deal w lower IATs is more oxygen molecules per volume. And when you are talking oxygen nothing beats alcohol, or methanol specifically.

meth is 49% oxygen by weight
ethanol is 34% oxygen by weight.
gasoline is zero% oxygen

And if you are into drifting, how much air do you think is going through the intercooler when your sideways? How much of a difference do you think that would make to AI? When you are pushing your ccp that high a cool air charge from an intercooler just starts to become insufficient.

AI is spreading through all of the high performance tuning communities like wild fire. Its probably time that it made a stronger presence in this one too.

fearlessKouki

wat psi/hp would a stock s14 sr20 intercooler be efficient??

codyace

Side mounts work 'ok' for stock levels, and not consistant beating. They heat soak entirly too fast, and often become 'interheaters' more than anything. To me they are no better than the FWD TMIC's that Nissan made. Even with ducting they just suck when you're really beating on them.


Size has nothing to do with spool, it's all abotu pressure drop. An efficient FMIC could technically support faster flow than a small sidemount


Obivously the FMIC location can put it in 'harms way' but I can say from consistant track abuse and spirited driving, that I've never had such an issue. Sure you can loose airflow through it due to a bug peening over it, but it's not something you need to check every week...maybe once a year if that. You'd be surprised how resilient they are.

REgardless, I wouldn't let that worry EVER deter me from going FMIC.


While true, don't you agree that a sidemount undoubtedly leads to more heat related charge temps than anything else? Trust me when I say, you'd be SHOCKED to see how quickly they retain heat and how quickly they become inefficient for anyhting but 'normal' driving.


LOL, yes you do. An efficient core will help any setup. Cooler the heat transfer the better. I'm not suggesting putting a 3" thick core that is 30" across, but a typical FMIC setup helps most if noto all SR20 setups. Total pipe length is probably darn near the same too.

While true, who cares about monitoring these things on a stockish setup when you KNOW a FMIC solves those issues and is more than capable?? Nissan engineers did their homework for an OE car, why try say we should stick with the sidemoutn and limit performance?

Honestly, who keeps their SR20 car stock, this side of a daily driver? Nobody. And even if they do keep it stockish, beating the hell out of on a SMIC is a terrible idea and just leads itself to all sorts of heat related issues.

SMIC is fine for a secretary driving to work, not some 18 year old guy beating it up all night.

Increases only if the core has a larger drop. Efficient core would work better, and fend of soak 10000X easier than the OE unit. Also, how would it abuse it? Abuse is trying to make that turbo pump hot air through a crappy SMIC.


Are you confusing alcohol with methanol?

Many companies do produce kits, but even a barebones kit is going to cost you 350-450 dollars to run. On a stock setup you also fight 'tuning' the meth injection to work properly with the power level. Ontop of that, the only way to really control it that cheap is with a Hobbes switch or something..which isn't really failproof or the right way.... 7psi @ 2500 RPM is much different than 7psi @ 5500 rpm...trust me when I say, hobbes activated meth cars suck.

No, you can't. It retains to much heat in the manifold from the hot head and engine bay. Maybe if you run ACTUAL alcohol, but not water/meth injection.

LOL maybe on a carb setup, nothing modern my friend. It doesn't work 'that' well, especially with the stock heatpump (t25) making some boost.


Sit back and think for a minute...if Alc/Meth/Water injection was REALLY that wonderful on it's own, why don't more professional motorsports just use that? Why do we continue to see Air to Air, or Water to air? From F1 to WRC, to Pulling trucks andGrassroots motorsports, intercooling exists for a reason. Now sure you can reference Top Fuel, but they are running straight Nitro-Meth...a bit different.

The point is it works properly all the time, and provides consistant results. I'll be the first to tell you that I love AI for track days, but it's not something I use all the time on the street as my intercooler works well.

Undoubtedly meth injeciton is wonderful, but even at drifting speed, the airflow across it works surprisingly well. Remember, if it keeps water cool, an air to air cooler will work just fine.

.
.
.

Take this as humbly as possible Hsitko, but it sounds like you need to step away from some of the engineering books you're taking for class, and spend more time working with it in the realworld with the parts. Trust me when I say, just because it works on paper does not coorelate to the real world at all. There are simple to many factors to consider other than flow rate.




7psi, without beating on it to long.

__________________

Want Air Conditioning in your SR20 Swapped car? Check out www.sr20acbrackets.com for more information!

Quest Alternator Conversions for SR20! Check my Group Buy!

Tired of lousy internal gates? Go external wastegate with one of my manifolds, Check out my group buy

ROOSEY

i got a s14 sidemount for 40 bucks if anyone wants to buy it haha

hsitko

Just two things. Codyace

First. Methanol is alcohol.
Second. Finding any actual pressure drop information on most of the name brand intercoolers is difficult. For some reason its not a stat that they advertise.

As for the rest. You have not provided me with any valuable data to back up your claims. Only conjecture and opinion. Thank you for your attempt to change my mind. I value other points of view and opinions. I tried to make a logical case for something based on actual evidence and data. I never stated that a front mount should not be run. Only that you should choose one based on power goals and use. But you took it personal and got emotional.

My data is posted. The info speaks for its self. I have no opinion any more.

codyace

Pressure drop could simply be measured with a reference before and after the aftercooler...way too easy.

When I use 'alcohol' I speak about fuel used for cars. It's not methanol that they use in the cars. Is methanol an alcohol? Certainly...but I don't use the terms on that sense. They are not interchangable iterms in most 'car guy' circles, so excuse my lack of technical backing.

And lastly, you haven't provided any information yourself. Sure I don't have everything written down on paper, but I do have first hand experience with this stuff, on mulitple platforms and in different forms. So while I may not 'convince' an engineer type, I will be able to say "I told you so" after someone switches with ill results; just because their isn't empirical data presented doesn't mean you should write someones opinion off as nonsense. If I did that to most old heads I wouldn't know what I do today.

If a sidemount was 'truly' a better option, you'd see more after market SMIC's, and more support/usage of them. The truth of the matter is that they were designed for an OE application, and an 'everyday' driver in mind. 10-14 psi, with abuse on the street all night or multiple passes in a row, is not what Nissan engineers (probably calsonic or garrett more than likely) built it for.

You simply can't combat heatsoak. I don't care if a hole is cutout of the side, with specific ducting...if the cooler itself isn't efficient at transfer it's not going to work. This is why you see HP (really torque) differences when people go from crabby Ebay FMIC's to Quality core FMIC's.



So while your calculations on needed processing make sense to you, the reality is your're not taking into account the two biggest things: Efficiency (pressure drop) and heat transfer rate (excuse my lack of technical terms). A stock sidemount is less than ideal in both applications for any member looking to use their car spiritedly. Granted many car modders are often guilty of being 'lemmings', but after 15 yeras of these cars (and other setups) being out there, there is a reason why you see FMIC's on them. Works on paper <> works in application.

__________________

Want Air Conditioning in your SR20 Swapped car? Check out www.sr20acbrackets.com for more information!

Quest Alternator Conversions for SR20! Check my Group Buy!

Tired of lousy internal gates? Go external wastegate with one of my manifolds, Check out my group buy

gordonliu

I am not an expert in combustion chemistry (though I am a chemist by education), I do not seem to remember a mechanism that accounts for non-molecular oxygen playing a direct role in combustion, and certainly not one that adds to the overall energy of the system.


you have to remember: a flame is an extremely complicated chemical system...


gas phase chemistry is never as simple and straight forward as you would expect from a cursory knowledge of the chemicals involved...


combustion involves reaction of O- radical anions (atomic oxygen, NOT molecular oxygen), R radicals (aliphatic/carbon radicals) H radicals, O2 radicals, R-OO radicals (peroxide radicals, including hydrogen peroxide)...



at the end of days, that OH in methanol and other alcohols DOESNT behave like oxygen (molecular)...


its function in the overall combustion mechanism is DIFFERENT, and thus its inclusion in the initial fuel has no impact on the combustion process itself.


in other words: the fact that methanol molecules include an atom of oxygen has absolutely no relationship with the amount of oxygen fuel (O2 from the air) that is used in the combustion process, nor does it affect the ACTUAL stoichiometry of a REAL flame (which is NOT the same thing as a general chemistry balanced equation of nCH4OH + mO2 -> xCO2 + yH2O).

the real stoichiometry of a real flame takes into account the mechanism of the chemical reaction, which the simple grade school thermodynamic representation DOES NOT.

tapdeznutz

wow very educational, keep up the good posts.

91sil80

my head hurts

__________________
91 TTZ

negrosx13

English please! The side mount is good for stock 7psi or 11 doesnt matter to me,Codyace is dead straight correct,you cant beat heat soak. even on 95+degree day,That greddy,blitz,godspeed,ebay junk dealing with heat soak better than a smic

__________________
MORE BACON STRIPS

Walperstyle

The intercooler's purpose is to cool air, and thus, make it more dense. In doing so, with most intercoolers, you can expect a -1 to -2 PSI pressure drop, pending on you plumbing and the size of the intercooler.

The size of your intercooler really depends on where you live. People that live close to the equator, or in Death Valley should get a larger intercooler. You want that air to be colder.

Up here where I am in Canada, we can get away with smaller intercoolers, because even in the summer, it rarely gets that hot, consistently. ...but, considering the price difference and the minimal Pressure drop, might as well go bigger.

but, I can't stress enough what was mentioned earlier on, the bold part is even more important.
There is a good saying that, 'everything relies on everything else and nothing is certain'

__________________
KA-T ORG-Function over Flush

jr_ss

Hot air leads to detonation, that is a fact... Side mounts heat soak, and although FMIC's can, it takes an either undersized core, not efficient core, damaged or extreme amounts of abuse to make it happen. There doesn't need to be any data, they work, in real world applications. No one is really going to take into consideration debris when they are beating on their car.

__________________
My SR20VET

Croustibat

For you guys who want hard evidence, i have a friend who took some temps measures. That is on a CA18DET, which produces less heat than an SR20, and the intercooler is nearly the same. turbo is a brand new T25, set at 15psi with supporting mods.

on a 15°C day, temp after turbo is 157°C .

OEM SMIC, IAT is 55°C after a couple of pulls. It gets worse with every pull. He stopped when hitting 75°C. 208HP torque 29mkg.

random ebay FMIC, IAT is 19° after a couple of pulls, and stays there after some more pulls. 222HP torque 31mkg. more torque and power is still there up to redline, while it goes down at 5000rpm on OEM SMIC.

Now, try that on a 30°C day and watch your pistons melt.

OEM SMIC for S13 and S14, is rubbish. It WILL heat soak, even with a stock engine and no mods, as it is made for a standard driving style. Dont use one if you drive your car hard. ever.

that and it gets covered in dirt qui often due to its position and is hard to clean, much harder than any FMIC .


A better intercooler, wether it is SMIC or FMIC, gives more power AND more reliability. I think it is the ONLY part that does that. You really should use one.

tapdeznutz

wow VERY GOOD INFO. thankx