Aftermarket turbos, air boxes

[shutterlug]

Since I'm doing mostly suspension right now, I've been hesitant to even lift up the hood to think about mods. More than anything, I'm curious. I have two questions:

What are the benefits of aftermarket turbos (besides more boost)? And what brands are most common?

What are the benefits of custom (or modified) air boxes? How hard is it to do?

I'm not a speed/boost freak, but adding a little something here and there is well in-bounds.

Thanks for your comments...

[jutny]

Originally Posted by shutterlug

Since I'm doing mostly suspension right now, I've been hesitant to even lift up the hood to think about mods. More than anything, I'm curious. I have two questions:

What are the benefits of aftermarket turbos (besides more boost)? And what brands are most common?

What are the benefits of custom (or modified) air boxes? How hard is it to do?

I'm not a speed/boost freak, but adding a little something here and there is well in-bounds.

Thanks for your comments...

re: Airboxes

just open up your airbox and take it out, and just use your head and say, how do i get air to flow better in this thing, and modify as you see fit, because they are a very stupid design from the factory, it funcitions as a muffler basically, which hurts flow and certianly velocity.

the gains for me were, +1-2mpg observed, engine sounds slightly throatier, and its probably just my head doing it but throttle response seems to be slightly more crisp as well, i can really hear the cbv now, and it sounds nice.

so overall, it took me 30 minutes and some pliers for breaking the inside of the box apart and there has been no downside.

[benflynn]

turbos...lower intake temps, faster/slower spool, more air per psi of boost, higher flowing exhaust housings, and cooler sig
air box...less restrictive

[SlowHo0ptie]

If you aren't a speedfreak, you could get more power than you want off the stock turbo. Improve the flow (intake & exhaust), better intercooler, maybe a more aggressive cam, and the mbc afr gauge combo. Putting a huge turbo on a stock system makes no sense to me.

[impulse922]

Originally Posted by SlowHo0ptie

If you aren't a speedfreak, you could get more power than you want off the stock turbo. Improve the flow (intake & exhaust), better intercooler, maybe a more aggressive cam, and the mbc afr gauge combo. Putting a huge turbo on a stock system makes no sense to me.

These are all very good mods if you arent a speedfreak as some of them aren't the best bang for buck mods.

[Mblesso]

the best thing you can do is mbc and 3" exhaust

[badvlvo]

Originally Posted by SlowHo0ptie

If you aren't a speedfreak, you could get more power than you want off the stock turbo. Improve the flow (intake & exhaust), better intercooler, maybe a more aggressive cam, and the mbc afr gauge combo. Putting a huge turbo on a stock system makes no sense to me.

Seriously good advice!

[lammmy]

Originally Posted by jutny

re: Airboxes

just open up your airbox and take it out, and just use your head and say, how do i get air to flow better in this thing, and modify as you see fit, because they are a very stupid design from the factory, it funcitions as a muffler basically, which hurts flow and certianly velocity.

the gains for me were, +1-2mpg observed, engine sounds slightly throatier, and its probably just my head doing it but throttle response seems to be slightly more crisp as well, i can really hear the cbv now, and it sounds nice.

so overall, it took me 30 minutes and some pliers for breaking the inside of the box apart and there has been no downside.

Ok, noob question here. I have modded the airbox, got 3" mandrel exhaust, mbc set to 10 psi, now one thing I hear people say on this board alot is about "hearing" the CBV...I would like to know what it sounds like? I mean, I should be able to hear it with my setup, but I don't know what I'm listening for, I know it's trivial, but I would just like to know

[brick_lover]

*steps on gas.....watch boost guage go to max boost, suddely let go of gas* PSSSHH!!!
tada, CBV!!

[saabnewbie]

Originally Posted by lammmy

Ok, noob question here. I have modded the airbox, got 3" mandrel exhaust, mbc set to 10 psi, now one thing I hear people say on this board alot is about "hearing" the CBV...I would like to know what it sounds like? I mean, I should be able to hear it with my setup, but I don't know what I'm listening for, I know it's trivial, but I would just like to know

Try listening for it without the radio on and the windows up on a quiet night. I have a stock filter and I hear it fine in normal traffic.

[linuxman51]

Originally Posted by SlowHo0ptie

If you aren't a speedfreak, you could get more power than you want off the stock turbo. Improve the flow (intake & exhaust), better intercooler, maybe a more aggressive cam, and the mbc afr gauge combo. Putting a huge turbo on a stock system makes no sense to me.

no one said it had to be huge, a 60/63 complements just about everything that can be done to a turbobrick without pulling the head off nicely, from low boost to upwards of 20. yes, you point out things that do need attention, but to pan the idea of a bigger turbo as not making sense contradicts the underlying idea of your post (improving systemic efficency).

[SlowHo0ptie]

I'm just saying that for what it seems like what he is after, it might be cheaper to get there with supporting mods. I wouldn't buy a new turbo until I was seeing the full potential of the one already installed.

[stylngle2003]

the modified airbox should be the first task you accomplish after your car is running properly, since it's free (or so cheap it's not funny...seriously we're talkin' <$10 here). don't bother replacing your airfilter with a K&N unless you can justify the cost increase (~$50 for the filter, $10 for the cleaner, versus $9 for a Mann filter that will last ~25,000miles...if you think you'll drive more than 150,000 miles on this current car, it starts to be a good deal). the stock Mann paper filter has been equipped on 400hp cars in sweden, so it really isn't a large restriction.

for another ~$400 or so depending on how well you shop and what mtls you decide to use, you could have a full 3" exhuast system with a high flow cat and at least 1 muffler, which would get you pretty nice gains too. after that, a ported 90+ manifold and (if you're running a mitsubishi turbo) ported turbine housing and an MBC will net you very large power potential. 93 octane gas, 12psi from a 13c, 3" exhaust, and a chopped airbox would be roughly 210-220bhp. throw in browntops for ~$50 more (easiest with lh2.4) and turn it up to 14psi, and you are prolly lookin at 225+bhp (pretty close to 200whp). from there, you will need a larger turbo, since the 13c isn't much good past 12-14psi anyway.

[945ti]

Originally Posted by linuxman51

no one said it had to be huge, a 60/63 complements just about everything that can be done to a turbobrick without pulling the head off nicely, from low boost to upwards of 20. yes, you point out things that do need attention, but to pan the idea of a bigger turbo as not making sense contradicts the underlying idea of your post (improving systemic efficency).

+1. I have a stock engine with basically that setup. Except for the very low end in 1st or so, there really isn't that much spool loss from the 13C the 60 trim replaced. 3" exhaust and a much ported 90+, turbine and WG likely help some there along with the 60 trim T3 (not T04E) wheel. I am barely running it in its effieciency sweet spot at ~9-10lbs. A bit over 11lbs and not a ton of abuse is enough to make the sachs sport clutch start to prepare for retirement.
a 2.5" free flowing exhaust is really pretty adaquate, and generally quieter and cheaper than its same counterpart in 3". Also easier to fit, weighs less, and easier to support to avoid cracking or stress that IMO mandates the use of a flexy and additional bracketry on a good 3" system. I think of a 3" DP being optional and a 3" high flow cat being a good idea if you run a cat. From the cat back, I might rather have be using a twin straight through muffler 2.5" system instead of the 3" to keep everything quiet, reliable, simple and cheap. The 3" came at a good package deal that I didn't want to pass up.

[shutterlug]

So, to sum up (just so I'm clear):

1. Aftermarket turbos are more of a luxury and better with a customized engine that can take the kind of a psi a heavier turbo would give.

2. Stock turbo works fine and can be improved by an aftermarket intercooler (brands, anyone?), making it more efficient and giving overall better performance.

3. Modifiying the airbox to increase airflow will have the benefit of improving mileage and sound of the engine. These modifications are easily done. Air filters are added luxury (but I do plan on keeping this car for 150K miles), but you can get by with a regular paper one.

4. Modifying the air box is easy.

5. A 2.5" exhaust system will increase efficiency of my car at a good price without causing too many problems.

So what about emissions?

[stylngle2003]

as long as you don't touch the existing systems (and by touch, i mean tamper or eliminate) you should pass emissions just fine. SMOG is another deal, one in which Cali takes the cake for most suckiest place evar to own a modded vehicle (maybe the UK is a close second), but i'm sure you're fine as long as you keep a cat in there.

aftermarket (or larger) turbos will flow more air which will help make more power. they will introduce less heat into the existing system, which will help make more power. they can ultimately work efficiently at higher boost levels, which will help make more power. it's really all about the tuning of the engine though, that is of more importance. you could keep your (guessing here...) existing setup pretty simple and throw on a Garrett .60/.63 T3 turbo from a turboford or merkur, put on ATPturbo.com's ultimate internal wastegate setup, and enjoy efficiency well past 15psi (i have heard 20psi+) and capability for ~250hp no problem. the plus side of that setup is that it is the same family of turbo as your stocker, so everything is pretty simple to reinstall on your engine. if youre swapping turbos, you may as well find a 90+ turbo manifold and port it out for maximum flow potential.

it seems most cost effective to optimize the existing turbo and associated ancillary systems before completely swapping turbo components out. that means putting in a freer flowing exhuast cat and downpipe, freer flowing intake system, better intercooler (you want an isuzu NPR intercooler which is almost a direct drop in, do a search for PSIC, NPR intercooler, UD intercooler, etc, to see what that entails), and a better cam (!). for a nice improvement on an automatic equipped turbo, i'd pick up a slotted A cam (think there's one for sale...). with the associated flow mods done, and ~12psi boost on the stock turbo, you should get nice healthy gains.

after that point, you should really consider looking into fuel system upgrades and turbo swaps

[945ti]

I wouldn't bother with the cam with stock LH. With decent flow otherwise, one can make plenty of power with the stocker T cam with the 6K rev limit and the amount of fuel LH can (easily) provide. There is little trade off that way in cold start, low rev performance, and one doesn't give up width of the powerband under 6k if one leaves the cam alone.
Some people like more cam and less turbo. I happen to like less heat buildup and making the most of my lowish redline from a turbo that has some more growth room than stock. The .63 housing might be a bit annoying in an automagic, but I am willing to trade a bit of spool for less heat buildup while making power.

[shutterlug]

Originally Posted by stylngle2003

as long as you don't touch the existing systems (and by touch, i mean tamper or eliminate) you should pass emissions just fine. SMOG is another deal, one in which Cali takes the cake for most suckiest place evar to own a modded vehicle (maybe the UK is a close second), but i'm sure you're fine as long as you keep a cat in there.

aftermarket (or larger) turbos will flow more air which will help make more power. they will introduce less heat into the existing system, which will help make more power. they can ultimately work efficiently at higher boost levels, which will help make more power. it's really all about the tuning of the engine though, that is of more importance. you could keep your (guessing here...) existing setup pretty simple and throw on a Garrett .60/.63 T3 turbo from a turboford or merkur, put on ATPturbo.com's ultimate internal wastegate setup, and enjoy efficiency well past 15psi (i have heard 20psi+) and capability for ~250hp no problem. the plus side of that setup is that it is the same family of turbo as your stocker, so everything is pretty simple to reinstall on your engine. if youre swapping turbos, you may as well find a 90+ turbo manifold and port it out for maximum flow potential.

it seems most cost effective to optimize the existing turbo and associated ancillary systems before completely swapping turbo components out. that means putting in a freer flowing exhuast cat and downpipe, freer flowing intake system, better intercooler (you want an isuzu NPR intercooler which is almost a direct drop in, do a search for PSIC, NPR intercooler, UD intercooler, etc, to see what that entails), and a better cam (!). for a nice improvement on an automatic equipped turbo, i'd pick up a slotted A cam (think there's one for sale...). with the associated flow mods done, and ~12psi boost on the stock turbo, you should get nice healthy gains.

after that point, you should really consider looking into fuel system upgrades and turbo swaps

:eek: Okay, I've read this now about three times and I think I'm starting to get it.

I will say that it's unlikely that I'd upgrade my turbo at this point, so I'd stay stock and try to get more out of it by using a better intercooler and modifying the air box. I did a little more reading on performance exhaust and I think I'm leaning more toward doing a 3" downpipe with a 2.5" exhaust system. What is stock exhaust on the 740?

Let me take a moment to say that I'm not normally a "car guy". For whatever reason, this Volvo thing has really struck something inside me. Part of it is I'm DETERMINED to make this a good car for me, the best I can (if you knew my history with cars, you'd understand). What I'm saying is I'm a little slow on some of these terms and things like cams are still a little beyond me. I did see iPd had a cam set on sale (and I just finished my taxes), but I wouldn't know the first thing about installing it. I know they look really cool, though.

So I think it's more likely that I'd upgrade my cam (like I know what I'm talking about) before I'd upgrade my turbo. Partly because the cam would be less expensive. But also because turbos can get "thirsty". I suppose my real dream in all of this is to get this running as the most efficient machine it can be. If a different intercooler is more effective/efficient, I want to do that. And this is why I want to add an e fan, as well. Does this make sense?

[stylngle2003]

makes perfect sense. plus, (no offense) you don't exactly live in the safest city in the world...so keeping some of the flash and jazz out of public knowledge would be a nice thing.

swapping in a cam will "technically" boost your engine's efficiency...but only really in terms of power production. you will use more gas in general if you have a sport cam in your car.

re: your efficiency thing, doing an intercooler, airbox mods, a ported 90+ exhaust manifold, and a 3"dp/cat w/ 2.5" exhuast would boost your engine's efficiency a good deal. if you could keep your foot off the loud pedal, you'd probably notice improved fuel economy. unfortunately, this is where the HP bug bites most of us, so don't be surprised if once you get to that stage, you want more

stock exhuast is something like 2.5" outside diameter (2.25" inside or so), and not particularly free flowing, so there will be gains even from a 2.5" exhaust. but i'd still do the 3" dp and cat since those are the largest restrictions

[shutterlug]

Originally Posted by stylngle2003

makes perfect sense. plus, (no offense) you don't exactly live in the safest city in the world...so keeping some of the flash and jazz out of public knowledge would be a nice thing.

swapping in a cam will "technically" boost your engine's efficiency...but only really in terms of power production. you will use more gas in general if you have a sport cam in your car.

re: your efficiency thing, doing an intercooler, airbox mods, a ported 90+ exhaust manifold, and a 3"dp/cat w/ 2.5" exhuast would boost your engine's efficiency a good deal. if you could keep your foot off the loud pedal, you'd probably notice improved fuel economy. unfortunately, this is where the HP bug bites most of us, so don't be surprised if once you get to that stage, you want more

stock exhuast is something like 2.5" outside diameter (2.25" inside or so), and not particularly free flowing, so there will be gains even from a 2.5" exhaust. but i'd still do the 3" dp and cat since those are the largest restrictions

No offense taken, BELIEVE ME. One reason I bought this car in the first place is because my Camry had gotten stolen...again. This is why lowering springs are not in my immediate future. I don't want anyone to look at my car and think it would be fun to take for a spin. Most mods will be under the hood and well out of sight. Who wants to steal a boring, old Volvo?

Now, will adding the exhaust make it a lot louder? I really don't want to be one of those guys who tears through the neighborhood making a racket (and there are plenty in my neighborhood). I've heard that it's louder as your rev higher. And it will still pass smog/emissions with a 3" dp? It seems strange to me that a larger exhaust system would make the engine run more efficiently.

Efficiency is good. I think I can keep my foot off the gas, I'm doing pretty well with it so far. The heavy ride seems to slow me down, still. Man, I really want my parts to come...I'm ready to get that thing rolling the way it should...

[yumling]

Originally Posted by lammmy

Ok, noob question here. I have modded the airbox, got 3" mandrel exhaust, mbc set to 10 psi, now one thing I hear people say on this board alot is about "hearing" the CBV...I would like to know what it sounds like? I mean, I should be able to hear it with my setup, but I don't know what I'm listening for, I know it's trivial, but I would just like to know

For my car it sounds like Darth Vader breathing!