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So noticed I need to replace the air filter. This has me wondering, is there any advantage to running a cold air intake, or modifying the intake box to take a conical K&N air filter???
Car is a stock 1992 SC300, 5 speed manual. Not going to be doing any performance mods, cause unless you have a few thousand to spend on a turbo, you are wasting your time.
Well anyways, that was my train of thought as to why I didn't do a cold air intake when I bought it a couple years ago. My main train of though now is if I can eek out some better gas mileage. The goal would be a 1.5 to 2mpg bump to make it worth the hassle IMO. Right now I'm getting 17-18 in town, 23 on the highway.
Any thoughts on this? Does anybody even make a kit for this car?
And I'm sure this has been hashed out before, but I checked the sticky at the top and didn't see a thread.
Also, in terms of factory airboxes, this one isn't TOO bad, compared to some of the restrictive crap I've seen on other "performance cars"
besides that, there's plenty of write ups on BFIs for the car (cutting a hole in the front of the intake box) PM me if you have any questions, i have a few bookmarks. if you want it to sound better i recommend cutting the box off the plastic part of the intake tube right by the throttle body and seal it up. it sounds fantastic, this is my car btw
Moved to performance and maintenance.
short of doing the BFI, they make a drop in K&N filter that fits in our factory airbox that is pretty decent. the oil on it can mess with the maf over time but it did seem to flow a bit more air and make a bit more power up top on the rear end dyno.
^^ I've read that the K&N can cause issues. I've been running one for a few years now with no trouble but it is due for cleaning soon and I will probably not continue to use it.
Aron, the TRD air filter is also a good alternative. The BFI modification does a bit more for SC400's than SC300's but it's still better than any cold air intake on this car/engine.
As for a 2mpg improvement in fuel economy, that isn't going to happen and certainly not from an air filter.
Our intakes sound really good with an aftermarket filter setup. However powerwise there is really not a noticeable difference being NA.
However cold air on boosted setups will significantly reduce knock, which increases timing and power. Heatsoak at the dragstrip is killer. I used to pull the headlight on the talon at the dragstrip everytime and see knock reduced.
^^ I've read that the K&N can cause issues. I've been running one for a few years now with no trouble but it is due for cleaning soon and I will probably not continue to use it.
Aron, the TRD air filter is also a good alternative. The BFI modification does a bit more for SC400's than SC300's but it's still better than any cold air intake on this car/engine.
As for a 2mpg improvement in fuel economy, that isn't going to happen and certainly not from an air filter.
A brand new oiled one will sometimes cause issues on the karman mafs (who knows maybe the maf was going bad anyways right? they are all old now). the 96+ hotwire mafs its not a concern you can just clean those with a can of maf cleaner. Don't toss it out the best part about them is when they get dirty you just wash it and now you have a really clean non-oiled K&N filter, and then what you do is wait for it.... just not re-oil it or if you have to oil it some do it super light, when you get them new they are like drowned in oil its ridiculous. I find it still works fine as a dry filter that way and doesn't mess with the maf in the longrun. its still a filter its going to stop most of it, I dont buy that the oil makes it that much better, as long as no rocks can get in I am happy.
another good option is those aem dryflow filters, those things flow ridiculous style and are not oiled at all, but they are expensive and not sure they make a drop in kind. mostly the cone variety.
and I did try a cone in the engine bay on one of my sc300's and didn't like it, seemed to just get more of the hot engine bay air, the power band moved from down low to a little up top but overall it felt the same if not slower. One thing I can say is it was definately louder and on one out of my 3 sc300's created a whistling noise... (still wonder about that one ) I wouldn't get rid of the stocker for just a cone. It would have to run to outside to be better than the stock setup or a BFI.
A brand new oiled one will sometimes cause issues on the karman mafs (who knows maybe the maf was going bad anyways right? they are all old now). the 96+ hotwire mafs its not a concern you can just clean those with a can of maf cleaner. Don't toss it out the best part about them is when they get dirty you just wash it and now you have a really clean non-oiled K&N filter, and then what you do is wait for it.... just not re-oil it or if you have to oil it some do it super light, when you get them new they are like drowned in oil its ridiculous. I find it still works fine as a dry filter that way and doesn't mess with the maf in the longrun. its still a filter its going to stop most of it, I dont buy that the oil makes it that much better, as long as no rocks can get in I am happy.
another good option is those aem dryflow filters, those things flow ridiculous style and are not oiled at all, but they are expensive and not sure they make a drop in kind. mostly the cone variety.
and I did try a cone in the engine bay on one of my sc300's and didn't like it, seemed to just get more of the hot engine bay air, the power band moved from down low to a little up top but overall it felt the same if not slower. One thing I can say is it was definately louder and on one out of my 3 sc300's created a whistling noise... (still wonder about that one ) I wouldn't get rid of the stocker for just a cone. It would have to run to outside to be better than the stock setup or a BFI.
Ha! Thanks Ali. So it will filter just fine without slathering it in new pink oil and just a wash? I may do that. I had a K&N drop-in filter on my Prelude and I re-oiled it twice (had the car ten years before the SC) and it was fine. I don't know what metering system Honda used on those H22's but I had no issues at 130k. I always left the re-oiled K&N to dry overnight before throwing it back into the car and driving. You're right that as these cars are getting really, really old it could be age of the MAF alone that causes issues.
I still want to try the TRD drop-in air filter though (although that is oiled as well?). It gets universal support from Supra guys. If AEM makes a good drop-in I'd give that a try too.
I have a factory MKIV TT intake box and piping waiting to go in with my swap and you can see how Toyota tried their best to duct in fresh air under the headlight with both the NA and TT box designs. They are so similar. The piping is the biggest difference. On the MKIV TT box there is this little duct that goes on top as well to suck in additional fresh air from, I assume, the "mouth" opening on an MKIV front bumper. We don't have that on an SC but the duct is at least fore of the radiator.
The factory air boxes don't look sexy but they do a pretty good job such as they are.
Honda's typically use the hotwire maf or a map sensor. they wont have the same issues of an oiled filter, its pretty much exclusive to karman type maf's although K%N won't and will never admit it.
haven't seen the TRD one, it might not be the same type as the K&N though toyota is usually a little smarter.
Aem dryflow are awesome but yeah you would have to look up sizes on that one not sure there is a direct fit.
Yes toyota did do a good job on the boxes, and the TT one having the extra opening is what helps it alot.
This is why on my n/a I just made extra holes in the front of the box and dropped in a very minimially oiled K&N filter. this way it still had the factory cold air scoop under t he headlight, as well as the couple of holes for when you really get on it. it would be best to BFI it in addition so the air it gets is cold air, or do like toyota did on the supra run it to the front middle part, but I don't think that stuff fits on our cars. I want to say the IS300 has a similar box and scoop.
One of the leading types of intakes though for turbo guys is to remove the factory box, drill a 4-5" hole in the car leadign down into the fender area, turn the intake pipe down into the hole and right after the hole put the cone air filter on. This setup gets no heat from the engine bay thanks to the frame/chassis setup, and it also takes advantage of the many slits by the fog light where fresh air can come through that is more or less trapped in the fender area before it exits by the tire. basically like a cold air ram system. the only possible downside is water but if you put the filter up high enough its not a problem, at least those who run it have not reported any issues. you would have to be in like 12"+ of water to suck some up and at that point any SC or supra will not be moving anyways despote where the air filter is located (note alternator location on the JZ engine is quite low). Surely it was not designed for crossing rivers or creeks.
Alternatives to the K&N filter. All of these are drop in replacements.
-AEM Dryflow. I don't have any experience with these but everything i've seen on the larger dryflow cone filters says these are good. I just don't know how they filter when compared to stock.
-HKS. It's a sponge type filter, a lot like ARC. Good for airflow but not the best for filtering.
-APEXi. Synthetic media, proven to filter the most as well as flow the most air.
-Blitz. Pretty much exactly the same as the APEXi but blue in color
JUST put up the HKS the guy above me showed, put it up this evening, it had the original before, and sounds better, and it feels like it breathes better. I wasnt sure with the sponge type, but i decided to go with it, mostly because its a good brand. Go for it man.
they're more expensive on ebay than horsepowerfreaks (some site i found while googling the filters) almost 20 bucks difference actually. i've bought SS brake lines from them so they're legit as far as i know.
10-08-14, 09:44 PM
Cold air intake on a stock SC300/5 speed.
or if you have to oil it some do it super light, when you get them new they are like drowned in oil its ridiculous. I find it still works fine as a dry filter that way and doesn't mess with the maf in the longrun. its still a filter its going to stop most of it, I dont buy that the oil makes it that much better, as long as no rocks can get in I am happy.
) I wouldn't get rid of the stocker for just a cone. It would have to run to outside to be better than the stock setup or a BFI.
