If your engine is stock, leave something that isn't broken alone. After I took off my OEM exhaust system for a custom dual exhaust with magnaflow free-flowing muffler, not only did I make the computer think it's misfiring in multiple cylinders (the engine is checking out fine in the electrical dept.)....I went to the drag strip again to see how much the new exhaust system helped. Well, I did more damage than good. Around town I didn't notice it, but flooring it in the quarter not only have I lost GOBS of lower off the line power....I just added 2 seconds to my times even on a good, hard run. I went from 17 seconds to 19 just because I refused to believe that any kind, shape or form of backpressure is unacceptable for an engine. So now? I've got a jaw-dropping sleek sounding exhaust system, but I paid the price once I hacked the stock system off.

I dunno what the factory O.D. of the size piping the exhaust comes out to, but I upgraded all the way up to 2.5 inches.

Unless you've modified the internals of your engine or top end, put on bigger turbos or chipped your car, stay away from exhaust system upgrades like the plague!!!!!! [:@]

I should have listened to S70Driver and left it alone. I have a 67 gto and I had this dumb idea in my head that if reducing backpressure in an old car increases horsepower, I could do it to my stock 99 S80 2.9 and pick up some ponies.

Take my advice......do your research before your imagination gets in front of your logic.

Oh well, around town it doesn't matter,...but I just made a slow car even slower. At least a redeeming aspect is the sound when you get on the gas is like the gods of thunder opened up and are yelling in anger .

Anyways, I probably shouldn't even be complaining. In the real world my car does seem to perform better around town...and racing performance for a daily driver to me is almost unrealistic. Still, something I thought I'd share with everyone.

When I get some money and finally graduate from college, I have some possible turbo setups and engine internals in mind.

 

That sucks but you paved the road for later. See it that way.

 

yeah, you have a point there.

At least my new exhaust will support the breathing capacity needed for upgrades.

Is there any way to flash or tune the computer for the new exhaust? I'm thinking if either a performance shop or the dealer could program the computer for the added airflow I could get the check engine light and the supposed misfire to go away.

 

Maybe an aftermarket tune may be able to do it.
I really don't mess much with the aftermarket stuff yet.
Still trying to buy myself a Volvo to try it all out.

With 4 kids always on a budget.

Was trying to work out a Deal with work for a 1999 S70 GLT with a blown motor.
They paid $700.00 for the car I offered $1200.00 like it is and they declined[:@]

 

I am glad you tested the waters for your NA. It is always fun to do so.

However backpressure in a NA is key. Unlike a turbocharged vehicle a NA vehicle requires backpressure. So going with a Magnaflow muffler wont help that since they are a straight through design. You should have gone with a Flowmaster muffler. Or one that contains baffles on the inside. This would create the back pressure needed.

I believe the stock O.D. on the exhaust is 2.25" so upgrade to 2.5" didn't help, but it would help the car breath better anyways. Just you needed a muffler to support the backpressure needed.

As far as upgrading an NA. IMO it is pointless unless you have gobs and gobs of money to do so. Suspension and interior exterior mods can be done, but engine wise you need money.

Just a short list of what you would need to support a turbo "upgrade" to your NA...

1. Intercooler
2.Turbo or turbos
3. Vaccum lines
4. Intercooler hard pipes
5. Turbo hoses
6. Bigger injectors
7. Downpipe or downpipes
8. ECU tune, and this is the key part here. If you get a crappy tune you will notice it. You will need to spend coutnless hours on a dyno to get a proper tune.

So before you get into this, think about it. Is it really worth it and do I want to spend the money. I would say you will spend anywhere from $3,000-$8,000 to do it right.

As far as an ECU tune helping you now. NA ecu tunes can be had, but they truly don't do much. You may see an increase of 5-10 Hp. No where near as much as turbocharged cars.

 

The big reason why I went with the magnaflow was the need for a tight-fitting muffler. Because of where the piping exits and there being no space for ANYTHING except a round case muffler, that was really the only option I had.

I would have gone with the flowmaster if I had the clearance under the car, but that wasn't a luxury I had so it was either that or not do it at all.

Also I guess at the time I knew I wanted to mabye turbo it down the line. Oh well.

 

I'm not trying to discourage you from turboing your NA. But I am forewarning you that it is a huge task, especially with the newer Volvo's. It just isn't worth it IMO, when you can buy a s80 T6 instead, and with a few mods you can get a nice increase of power in upwards of 300Hp.

 

He is completely correct here.

If say you went to 3", your car might not even start at all...

 

He is completely correct here.

If say you went to 3", your car might not even start at all...

 

i no the feeling. but didnt have to pay asmuch. i bought a cherry bomb for 20 bucks.its a 2 inch id glasspack.
im going to reduce the piping off the muffler to 1.5 inch id

 

awwww im sorry to hear all of this. Unfortunatly as most of us know, tuning a car is not as simple as buying a decent part and slapping it on. It takes forethought and planning. Usually if you upgrade one thing, you have to upgrade another. I learned that when i put springs only in my 99 eclipse. I learned for that modification i needed to add camber kits. So i did that, but then i had to keep making minor adjustments to keep the alignment, so i had to take it all apart again and add some improved struts. It was quite the headache. Should have done it right from the start.

but as they say , a smart man learns from his mistakes, and wise man learns from others mistakes.

 

Don't reduce it. Just leave it at stock spec if anything..

 

it would just be silly to go from na to turbo....you might as well just sell it and get a turbo car...

 

Jeez you guys with turbos really try and shove turbos down peoples throats all day long it never ends. I have a non turbo s70 and I've made a few mods that have definately improved performance. Custom cold air intake, stainless race headers, a high flow cat and muffler. New wider wheels and tires and some Ngk irridium performance plugs! And yeah we upped the pipe to 2 and half inches from the catback. This car runs much better than stock!

 

good to know

 

One thing that has been overlooked here is the difference between a turbo and non-turbo engine. The non-turbo has a higher compression ratio, since the turbo model is receiving a compressed charge of air the compression ratio is designed to be lower so the internal engine components can handle the pressure. If you add a turbo to a non-turbo engine you have to be very careful about how much boost you run, it won't handle as much as one that was designed to have a turbo. Just something to note.

 

What upgrades are you speaking about? I have a S80 T6 and I have no idea what to do. Any help would be appreciated.