Aftermarket Intake Horsepower Guess Poll

[Myxalplyx]

I just wanted to get a head count on opinions on how much horsepower a fully custom made intake could yield on an SVX with the exhaust already done. When I say exhaust, I mean with a custom made exhaust from the exhaust port back. Pick the exhaust configuration that you think is perfect for the SVX. Once this is installed, how much hp do you think a custom (Meaning that all the piping before the throttle body has been modified) can make. It does not matter what the intake setup is (for those that don't think it matters), just assume with the best made intake possible (besides the stock one).

1) Less than the stock intake,

2) 1 - 5hp,

3) 5 - 10hp,

4) 10hp +

[Landshark]

I just wanted to get a head count on opinions on how much horsepower a fully custom made intake could yield on an SVX with the exhaust already done.

fixed. <added content for short-ass reply>

[It's Just Eric]

You and your intakes:rolleyes:

Is this poll for the intake AND exhaust hp gains compared to stock, or is it the intake gains after custom exhaust. If its the first, ill say 5-10, if it's the second...1-5. Numbers id put my money on are 10 and 2

now...remembeing that chike's car has had the cams, and presumebly fuel pump, injectors, and an ecu chip done...an intake and exhaust could possibly yeild more on his engine that a stock one, due to the increased time the valves are open, ect. But once again, I dont think the intake and exhaust are overly restrictive

When you say no paricular exhaust configuration, please specify weather the car will be street legal or not...Seems to me straight pipes with MABEY a muffler would be "the best", but it'd probly have a hard time passing inspection

[Myxalplyx]

You and your intakes:rolleyes:

Is this poll for the intake AND exhaust hp gains compared to stock, or is it the intake gains after custom exhaust.

After custom exhaust....any exhaust...of your choice that you think is best fitted for the SVX.

And thanks for your responses so far.





When you say no paricular exhaust configuration, please specify weather the car will be street legal or not

Street legal!!

[jman050]

i think you will loose power with any intake setup other than maybe a true ram air setup if you were to create it.

[Ricochet]

How can an unrestricted straight piped intake make you LOSE power over a curvy thin plastic box contraption?

[Darren]

Unless your running a feed from outside of the engine bay your going to lose power due to high inlet temp,
I put an HKS induction kit on my type r impreza and it lost power and torque & much higher inlet temp on the before and after rolling road sessions.

With the boxer engine any filter/induction is going to sit above the manifolds and as we all know hot air rises and the svx has no ventilation or cold air feed other than the small front grill.

[Ricochet]

With the boxer engine any filter/induction is going to sit above the manifolds and as we all know hot air rises and the svx has no ventilation or cold air feed other than the small front grill.
...............what? Just buy the stage 2 or 3 or whatever intake from dayle's warehouse page, they go into the bumper.

[jman050]

...............what? Just buy the stage 2 or 3 or whatever intake from dayle's warehouse page, they go into the bumper.

i take it you have an aftermarket intake and want to justify why you bought it. The svx isnt the only car that responds best to the stock airbox. Go over the the 350z forums and you will find the same thing.

[Ricochet]

............what? You were saying something about air being fed from under the hood, above the manifolds or something. I was just saying the air is fed from under the bumper.. and I don't need to justify anything, I just wanted some noise. My svx, nor anyone's svx, will ever be fast so I'm not going to even try.

Can you justify your ubercoolsuperexpensive magnaflow exhaust mod? I bet you're beating all the corvettes in the world now. And by corvettes I mean 4 cylinder accords.

[NikFu S.]

After exhaust work, I say an intake will yeild no gains, unless somehow your intake forces a bit more air in.

[jman050]

............what? You were saying something about air being fed from under the hood, above the manifolds or something. I was just saying the air is fed from under the bumper.. and I don't need to justify anything, I just wanted some noise. My svx, nor anyone's svx, will ever be fast so I'm not going to even try.

Can you justify your ubercoolsuperexpensive magnaflow exhaust mod? I bet you're beating all the corvettes in the world now. And by corvettes I mean 4 cylinder accords.

I NEVER said anything about air being fed from under the hood or anything about manifolds. I was just stating what i have seen as fact and that no intake will show gains over the stock intake unless its some sort or ram air (which i have not seen dyno runs of so i cant comment on the power increase or decrease) and dayles kit does not feed from under the bumper it feeds from the fender just like the stock intake.

yes i can justify my magnaflow because my stock muffler had a hole in it and it was cheaper to go aftermarket and it will be justified even more when i put on a 75 shot. And dont you think you are kinda jumping the gun and insulting many of the people in the svx community that have made 5spd/6spd, superchargers, cams, forged internals possible by saying no ones svx will never be fast. Maybe you should just stick to what you know and say "My svx will never be fast."

[Darren]

I dont want to open a whole can of worms but basically induction kits/filters are an aftermarket item that is not of much value per ££ spent on most cars, more so subaru because they actually do a good job on R&R from the factory!

Its not all about the amount of air you can force into an engine when you are looing at anything producing over 150 BHP air temp is a major factor, hense why virtually every Turbo vehicle runs and intercooler, the cooler the air the denser is it there forfore more O2, my Impreza runs a spray onto the intercooler to keep temp down and my Evo had water injection to do both.

All the (mushroom) filters are doing is taking large particles from the air that is HOT from the engine bay, the factory air box will be fed from outside of the engine bay and as it act like a storage unit will actually cool the air by 1 to 2 degrees.

The only way and after market set up will work is if as mentioned if it can produce either a ram air effect ( forced induction from air speed) or by supplying the engine with cool air, IE from out side of the HOT engine bay.

Have a look at the induction on any evo or high performance motorsport homologated road car and you will see an inlet system from outside of the engine bay and not the inner wheel arch in most cases.

[Ricochet]

They probably add maybe 1-2hp but that's why I said I got one just for the neato sound.
I NEVER said anything about air being fed from under the hood or anything about manifolds. I was just stating what i have seen as fact and that no intake will show gains over the stock intake unless its some sort or ram air (which i have not seen dyno runs of so i cant comment on the power increase or decrease) and dayles kit does not feed from under the bumper it feeds from the fender just like the stock intake.

yes i can justify my magnaflow because my stock muffler had a hole in it and it was cheaper to go aftermarket and it will be justified even more when i put on a 75 shot. And dont you think you are kinda jumping the gun and insulting many of the people in the svx community that have made 5spd/6spd, superchargers, cams, forged internals possible by saying no ones svx will never be fast. Maybe you should just stick to what you know and say "My svx will never be fast."
Show me an svx that runs 10's and I'll edit my post :)

[Sov13t]

I tend to agree with Ricochet on this one, I got an air intake for two reasons, one being the look it adds under the hood, and also the life span and quality of the filter. On the other hand, if you remove the under carriage (plastic cover sealing the right fender compartment) one can argue that the air temperature is going to decrease and the flow increase, thus perhaps being better than the stock air box.

As it has been stated over and over on this network, our cars are designed for luxurious/style aspect rather than speed. And then yet again, there are a few members on here that are pushing the limits of these cars and redefining their performance capabilities (talking about Toms, dynomatt, and a few others (sorry I fail to remember nicknames as easily as names)).

My two cents on this subject,
-Sov13t.

[sicksubie]

They probably add maybe 1-2hp but that's why I said I got one just for the neato sound.

Show me an svx that runs 10's and I'll edit my post :)

Okay.......

[jman050]

They probably add maybe 1-2hp but that's why I said I got one just for the neato sound.

Show me an svx that runs 10's and I'll edit my post :)

so i guess a car isnt fast unless it runs 10's....which goes for just about every production car ever made. "fast" is just someones opinion but i think most people will agree that a 500hp viper is "fast" as well as many other cars that arent 10 second cars. IMO the 13.2 second svx is fast, as it is on par with c5 corvettes and ls1 f-bodys and many other cars.

And your comment wasnt stating that there arent any fast svx (which in your opinion there might not be) it was stating that there will NEVER be a fast svx.

If you got your intake for the neato sound thats fine and i have nothing against that. I have done plenty of things for the "coolness" factor alone but i dont claim gains that have been shown to not be there. ;)

[Myxalplyx]

Figured I put my 2 cents in and say 10+hp. This is only based on previous dyno's with other subarus of mine with aftermarket vs stock intake. Yes, they are different models but still.

I am looking for a stock resonater to install with the stock intake and will be purchasing a new stock air filter for testing (Currently an STI air filter is installed).

[Myxalplyx]

+19whp @ 6000rpm, +16.74 ft-lbs @ 6000rpm
ToMyx Intake-->
http://subaruxt.com/forum/files/tomyx-intake1.jpghttp://home.comcast.net/~thomasck/mini-ToMyx-Spyphoto1.jpghttp://home.comcast.net/~thomasck/mini-ToMyx-Spyphoto2.jpg
http://subaruxt.com/forum/files/tomyx-vs-sti_panel-hp.jpg

Not to double post but wanted to draw this thread to a conclusion. Posted more info in another thread. Thanks for responding. ;)

[sicksubie]

wow.................

[shotking]

wow.................

double wow

[AppStateSVX]

HA, i love it. I've been saying this for years, an intake is NOT a wasted mod. There is a reason 98% of race teams in the world do NOT use stock intakes

[It's Just Eric]

......wow
Now, I know that your engine isnt quite stock (I WATCHED the cams go in) but dare I say it:


You'd actually have hp gaines on a stock engine too:eek:

I'd LOVE to see what kind of gaines are seen by the boosted guys.

[Mike621]

Kevin, thats an impressive gain! I'll be watching for more development.

[ridered777]

Hmmm...

When do you start producing?! I'll take one...:p

[94SubieSVX]

Hmmm...

When do you start producing?! I'll take one...:p


+1 agreed

[NikFu S.]

/me eats hat.

[nonSTOP_service]

As it has been stated over and over on this network, our cars are designed for luxurious/style aspect rather than speed.
I hope you don't mind me pointing out that I believe the SVX holds great potential to be some kind of top speed demon. It's 3.3 litre engine yearns to be tapped to it's full potential.

I know it'd probably be a waste of money, but I could easily see someone tossing together a 200 mph SVX.

As for a + for the modified intake, I can personally say that when I placed my generic cone filter on my car (with the still stock piping) I noticed a definite increase in overall throttle sharpness. Really it's as sharp as I could expect an automatic car to be.

[shotgunslade]

The EG33 is a very attractive engine outside of our community. It has a long history as the powerplant for experimental aircraft, often in a turbo-charged application. We've seen posted some images of twin turbo drag race machines.

Jack Laverty at XX Tuning ins Ct. has been driving an NA EG33 Subaru RS coupe at NASA racing events for a couple of years. Check threads at Nasioc for pic's. I spoke with him at Watkins Glen last weekend, and he will be installing a full top end re-do over the winter. Ported and polished heads with a valve regrind and some pretty wild camshafts. Good-bye non-interference. He has ditched the entire ECU and is running a stand-alone system (non-smog legal). He also has a ram air intake system using a hood scoop. I've ridden in the car and it's pretty strong.

The EG33 is one of the best things about our car. For those of us with manual trans, the direct responsiveness and willingness to rev is very sweet. Through the efforts of old and young Tom, Lan, Bill, Kevin, Benebob, Hocrest, Huck,Todd and others, I think we're really beginning to see just how good this engine can be. Their efforts have added immeasurably to my pleasure at the track. :D:D

Dan

[nexus_7]

I need more $! :o

[TomsSVX]

Oh boy... thats gonna be a tricky jig:o

Tom

[shotgunslade]

I have been running the polished aluminum intake tube from Motorsports Warehouse for a couple of years now. While it uses the stock plastic divided connection to the throttle body intakes, it replaces the corrugated tube that runs between that connection and the MAF. There was a thread a couple of years ago discussing whether or not this corrugated tube caused any significant pressure drop in the intake path. I did a calculation that indicated that air velocity in this pipe would be very high, approaching 2000 fpm. TomsSVX did a GTech "Before" run prior to his intake cam/5MT install on my car that indicated 178 hp at 5600 rpm. While that was only GTech and not a real dyno, it suggests that the stock intake tube of the SVX offers significant opportunity for upgrade and horsepower improvement. Anybody who is worried about conduction heat gain thru the pipe can just wrap it in foil and foam ductwrap, just like I did to my intake tube.

http://www.subaru-svx.net/photos/files/shotgunslade/28926.jpg

Put me on the list for one of Kevin's new and improved models.:)

[TomsSVX]

well I believe the removal of the "air box" that connects the snorkus to the throttle bodies is the cause of the gain here. But thats just me. Dan, I will see when I can fit in making another one

Tom

[shotgunslade]

Tom:

I'm sure you are right that a lot of the pressure drop is in the "air box", but I also think that there is some drop in the snorkus, the removal of which may be why my stock engine was a little perkier than most.