Horsepower question?

[Tommio 3.1]

Hi I have a 93 chevy lumina 3.1L and i was wondering how much power could i get by putting on a new intake system? and how much power could i gain by getting a high flow cat or no cat.

Thanks!

[jeffcoslacker]

The monolithic cats GM uses are pretty free-flowing...Unless you are making serious horsepower you don't need to contemplate a cat delete or upgrade...unless you have reason to believe there's something wrong with yours.

Wild guess I'd say a CAI with a K+N type filter and a performance muffler(s) might get you another 5-10 hp but don't increase the exhaust diameter, you'll loose low end torque and throttle response.....

I just busted out some 1.5" holes in the sides and bottom of my stock airbox and use a K+N panel filter (OE type) and it seemed to respond slightly to that at WOT...or could be it just sounds better, which it does.

If the stock exhaust would ever wear out so I could justify replacing it I'd try a Flowmaster 50 Delta series can or something similar on it...

[Tommio 3.1]

Well right now i have no cat. on my car because it was totally rattling apart. Once i cut if off, TONS of chucks of white crap fell to the ground. So i stuck a straight pipe on. The sound is better now and has faster response. Reguarding the Intake system, I just removed the intake box and filter only leaving the rubber intake tube to the throttle body and stuck a cone filter on the tube. I took the IAT sensor out of the air box and zip tied it near the filter end. So basicly the car is free flowing except for the 5 year old muffler.

[jeffcoslacker]

If your cat feel apart the muffler may be partly restricted with cat debris...seen it happen.

[Tommio 3.1]

That does make sense. But it seems to be flowing perty good right now. I might change it in a year or soo or if it gets bad for some reason.

[Mediaman67]

how does your car pass emmisions without a cat? or do you "know a guy" - actually, I just found out that by Oct of next year, any OBDI car will never have to have an emmisions test, so I bet a lot of people will be removing their old CC's for the increase in power, and sadly, pollution...

does K&N make an intake for the 3.1 GM engine?

[jeffcoslacker]

Originally Posted by Mediaman67

how does your car pass emmisions without a cat? or do you "know a guy" - actually, I just found out that by Oct of next year, any OBDI car will never have to have an emmisions test, so I bet a lot of people will be removing their old CC's for the increase in power, and sadly, pollution...

does K&N make an intake for the 3.1 GM engine?

Depends where you live...here there's only 6-8 counties that get emissions tested.

K+N doesn't make anything but the panel filter for 3.1 Lumina or Monte...

[richtazz]

The GM 3.1 engine doesn't take well to mods. IMO, you're wasting your money with a CAI, free flowing exhaust or any other performance mods. You'll spend $500 for maybe 3-10 HP, and with a K&N (or other cloth gauze type filter) you'll be allowing more dirt in your engine shortening it's life.

[Tommio 3.1]

Well its too late I have no cat anymore and i removed the stock air box and replaced it with a cone air filter. The car sounds bad ass at all revs, has much better pick up and runs super smooth. Its kinda like a new car but much louder!
I like it!

[jeffcoslacker]

Originally Posted by richtazz

The GM 3.1 engine doesn't take well to mods. IMO, you're wasting your money with a CAI, free flowing exhaust or any other performance mods. You'll spend $500 for maybe 3-10 HP, and with a K&N (or other cloth gauze type filter) you'll be allowing more dirt in your engine shortening it's life.

Maybe it wasn't on this forum but I previously dismantled that argument about K+N filters based on the popular testing that people like to cite for that assertion...

When you get into the small print and actual data from the test you see that the test itself was a sham because they used a different sized grit on the oil/cotton filters tested, because they flow better and and are made to be serviced...so in order to get the numbers that seemed to show the K+N type filters passing more dirt, they actually had to throw a grit size at them that the conventional filters can't even catch....

When you interpret the data correctly, rather than just looking at the amount passed through the filter, the K+N flows better, and catches SMALLER particles than a paper element filter.

Mine's been in for 75,000 miles outta 140,000....still runs like new, uses no oil. No premature wear happening here...only been cleaned once.

[J-Ri]

Originally Posted by jeffcoslacker

Maybe it wasn't on this forum but I previously dismantled that argument about K+N filters based on the popular testing that people like to cite for that assertion...

When you get into the small print and actual data from the test you see that the test itself was a sham because they used a different sized grit on the oil/cotton filters tested, because they flow better and and are made to be serviced...so in order to get the numbers that seemed to show the K+N type filters passing more dirt, they actually had to throw a grit size at them that the conventional filters can't even catch....

When you interpret the data correctly, rather than just looking at the amount passed through the filter, the K+N flows better, and catches SMALLER particles than a paper element filter.

Mine's been in for 75,000 miles outta 140,000....still runs like new, uses no oil. No premature wear happening here...only been cleaned once.

I'd love to see the data that was based on. I've seen dust in the air intake on vehicles with K&N filters, not just a light coating either. Even with all the dirt roads I take with my vehicles, there is far less than on K&N vehicles which I'm pretty sure were city only vehicles.

Even if there is an increase in HP, it's at the crankshaft. So by the time it gets to the pavement, there is almost no increse at all.

[dinok]

I got to ask this, if you gain with free flowing system and trotle response, what's about your fuel consumption??
Do you see any drop in MPG or increasing MPG which I doubt that you can get with free flowing system, right??

[Tommio 3.1]

Well i did all my work to my lumina eg: straight pipe for a cat. and cone air filter for instead of my air box. I probably gained with all the work a couple of MPG and hell the car sounds and has just better response! So if you can do it for cheap do it! I did all that work for $25 that because i bought the air filter.

[dinok]

so, which cone filter did you get?? And how did you install it??
Where to get them?? AUtozone, pep boys, etc...???

Thanks.

Dino

[richtazz]

Until I see a timeslip that shows a performance gain using a K&N or CAI, I'll stick to my guns on this one. I sell MAF sensors all day for cars using cotton gauze/oiled filters due to the oil getting in the MAF element ruining it, so I say the real world known disadvantages outweigh any theoretical advantages.

The factory air box on these cars can flow 600+ cfm, and even a 350 CI V-8 only flows 593 CFM at 5500 rpm. All the claims of flowing more air mean diddly, because the car cannot ingest more air than the stock air box can supply. It's like the old days when guys flipped their air cleaner lids over, you can hear the engine sucking air, and it sounds different, but does NOTHING to boost performance or economy.