2 questions

[RedlineRacer]

Question #1:
I took out the factory air box yesterday and put in a cone filter. Now, whenever I am driving, it feels like my clutch is slipping whenever I change gears, but I don't have the clutch in. Like I put the clutch in, change gears, and let the clutch out while giving it gas and then right after I let the clutch all the way out, the car revs to about 3k rpms and then goes down to where it should be. Do I need to reset my ECU? This is the only thing that I can think of that would be causing this. Also, whenever I am casually driving and then want to get on it alittle, and get the rpms around 3k, it studders a second and then goes like normal. I seems like its not getting enough air in that area.

Question #2:

What tire size would you recommend for a 8" wide rim? I was going to use a 205 wide tire, but I think that may be too skinny. Would a 215 or 225 be better?

[misnomer]

Uh

If your clutch is fully engaged and it's revving to 3k then dropping, you've got a slipping problem. I can't think of anything else that could cause that.

[black s13]

your ecu has no idea what the clutch is doing, other than maybe the switch that says the pedal is down. the ecu also doesnt know that you removed the airbox, that is if you got a good system and still have all the sensors hooked up...

as for the bogging, replace fuel filter, oxygen sensor and check your PCV valve, those helped me.

[docrice]

in addition to that last bit, run fuel injector cleaner. its like $2.50 a bottle and it's saved me some trouble before....in fact, i like to run it every 2K miles or so just to keep everything clean

[RedlineRacer]

If it is the clutch, then why does it stutter and act like it wants to stall out when I get around 3k rpms with normal driving? Thats why I think its the filter or something I did that pertains to the intake. Also, I put on my CAE and it would stall out everytime I started it with it on. By the way, I use that injector cleaner everytime I change my oil.

[black s13]

with the CAE you have to keep the MAFS on, or the car wont run. im guessing you took it all off, so your intake was all piping, correct??

[Dream240]

Originally posted by docrice
in addition to that last bit, run fuel injector cleaner. its like $2.50 a bottle and it's saved me some trouble before....in fact, i like to run it every 2K miles or so just to keep everything clean

What brands do you guys use? I use Lucas fuel cleaner, That stuff is so potent you only need it every 12 months. As far as putting it in every 2K miles...that could get dangerous. I hear that using any fuel additive excessively can cause premature wear on valves, fuel lines, etc. I think you really only need the stuff at least every 6 months, or once a year. Unless you're running turbo and NOS, then I have no idea how it affects your engine. But NA engines with bolt ons should be treated like a stock engine.

Any one else have an opinion on this?

[docrice]

well i use it just as the bottle suggests, every oil change (~2-3K miles). i usually just use the $2 stuff at walmart, Gumout or STP or whatever. i first ran it cause when i bought my car it had a stumbling problem that really got to me (it had been sitting a while), so i ran out the 3/4 tank of gas the dealer had put in it and put in some fresh stuff and STP cleaner...who knows which one did the trick, but its worthwhile to do from time to time for regular maintenance.

[Dream240]

Originally posted by docrice
well i use it just as the bottle suggests, every oil change (~2-3K miles). i usually just use the $2 stuff at walmart, Gumout or STP or whatever. i first ran it cause when i bought my car it had a stumbling problem that really got to me (it had been sitting a while), so i ran out the 3/4 tank of gas the dealer had put in it and put in some fresh stuff and STP cleaner...who knows which one did the trick, but its worthwhile to do from time to time for regular maintenance.

Right regular maintenance is good. You buy the stuff from wal mart? Uhhh...ther's a reason that stuff is so cheap, it is cheap. Sure it'll clean out the fuel system and stuff, but it leaves alot more residue and deposits that don't burn up in your fuel. It could eventually do more harm than good. I guess what I'm trying to do is sway you toward the Lucas stuff, I mean it's 4.00 a bottle every six months, and I'm sure if you ask around, the stuff is the best, and don't we all want the best for our babies?

Here's a good testimonial, I used to drive a 86' accord hatchback, great car, 210,000 miles and I used the Lucas oil stabilizer every oil change from 150,000 when I bought it to when I sold it. The Honda guys did a tune up one time and said they've never seen a honda engine with that many miles have such perfect compression. After that I only use Lucas goodies on my car, oil stabilizer, tranny fluid stabilizer, fuel cleaner, etc.

It's entirely your choice, but I always think like this, if it's a cheap costing product, then it's doing cheap stuff to your engine.

[Dream240]

Originally posted by docrice
well i use it just as the bottle suggests, every oil change (~2-3K miles).

Ohh, also there's a reason why they tell you every 2-3K miles on that STP stuff...they want you to buy more!!! Shoot I would put that on my label to sell my product more frequently, wouldn't you? I'm not trying to preach, but just trying to give you some money and engine saving advice.

[AKADriver]

Originally posted by RedlineRacer
Question #2:

What tire size would you recommend for a 8" wide rim? I was going to use a 205 wide tire, but I think that may be too skinny. Would a 215 or 225 be better?

8" what?

15x8? 16x8? 17x8?

15x8: 205/55, 205/60, 225/50
16x8: 225/50, 225/45
17x8: 215/45, 225/45, 235/40

[uiuc240]

Fuel Injector Cleaner isn't that special. Almost all the same additives are in Premium Unleaded. Just buy one tank of that for the same effect.

Eric

[Red]

Originally posted by uiuc240
Fuel Injector Cleaner isn't that special. Almost all the same additives are in Premium Unleaded. Just buy one tank of that for the same effect.

Eric

You dont run your car on Premium all the time???????? Weard the only thing I stick in is the good stuff.

I just ran some high $$ injector cleaner in my car. It helped quite a bit.

Btw the only way your can can rev to 3k then drop back down is if your clutch is slipping. well I guess it might not be slipping and just cutting you off at 3k... Did you screw up any of your MAF wires?

EDIT: Go to www.tirerack.com for your tire sizes... just click on a brand or tire and go to spec's it will tell you what size tire fits what rim.

[AKADriver]

All fuel coming out of the same pump has the same detergent additives. The gas companies only advertise them in the high octane to get people to pay more for a grade of fuel that they don't need.

But a KA24DE should run 91 or better anyway as per the owner's manual... and the SR20DET was recommended to run ~93 (98 RON).

KA24E cars should be using 87 unless you've increased compression, added forced induction, advanced timing, or reprogrammed the ECU.

[uiuc240]

Originally posted by Red
You dont run your car on Premium all the time???????? Weard the only thing I stick in is the good stuff.


yes. that's all i use. not all people do with a KA. i have an SR, so i'm on 93 every time. 94 if i can find it.

I've read other articles that say the premium comes with more additives...but I can't quote them right now. Whatever. It was just a bit of advice. I have used the cleaners before too...they never really seem to do anything. Blah.

peace out

E

[RedlineRacer]

Originally posted by black s13
with the CAE you have to keep the MAFS on, or the car wont run. im guessing you took it all off, so your intake was all piping, correct??

Of course not. I wouldn't even be able to drive my car if I took it off. And the whole reason I was talking about my clutch was used as an analogy. My clutch is fine. This all started when I changed my air filter. The only thing that is not hooked up is a hose that connects to the filter box. I searched on it, and someone said it is safe to leave off, so I did. But they might have been wrong...are they? Also, I use STP fuel injector cleaner. I also try to use the best I can for my engine. I always run 91 or 93 (whatever is premium at the gas station I go to) octane and use havoline oil (not some cheap *** Advance Auto brand). I try to baby my car. I rarely rev it high or get on it hard.

[RedlineRacer]

Maybe it could be because of my air filter. I bought this cheap air filter off ebay that came with my filter adapter. I thought all filters are the same. Could this be my problem?

[Red]

What you could do if you wana semi risk it... Take off the filter totaly... Then drive a few miles and see what happens. Then you would know if its the filter. no filter should run fine.. I have done this.

[black s13]

unless the filter is so restrictive that it bogs the engine, it cant really do anything. and no, all filters are not equal. there are reasons that you can buy a $5 fram filter or a $50 K&N, that do the same thing, but the k&n will clean the air better, flow better, and its reuseable.

running without a filter is fine, just no dirt roads, or small mammals. the hose that comes off the side is some ventilation thing or something, throw a breather on it and you should be fine, or go the good way, and buy a injen intake that has places for ALL the connections.

replace all that little stuff i said before, oxygen sensor, PCV valve and fuel filter, but get a fuel filter for a 300zx TT, its like twice the size of a 240 filter, and the butt dyno shows slight pick up improvements.

[RedlineRacer]

You guys were right. Part of the problem was my fuel filter. I changed it out and put in a 300zx fuel filter and it doesn't lag when I take off anymore now. Get this, I think my old fuel filter was the factory one. It had no brand name anywhere on it and all that was written was some serial number. But, I don't see how it could still be my factory fuel filter with almost 99k miles on it. Wouldn't this have killed my engine?

[Dream240]

Well, probably not killed it, but I'm sure it got so dirty that it was seriously restricting fuel flow, especially when you put the pedal down.

I had this same scenario on my old Honda. When I went to replace the fuel filter it looked like the factory one, because I broke the paint seal while removing the filter from the bracket. And this was with over 200,000 miles!!! Scary....

[RedlineRacer]

Could this be because of too much back pressure? I took my muffler off about 3 weeks ago. Also, what about a fuel pump? This be a cause?

[Dream240]

Originally posted by RedlineRacer
Could this be because of too much back pressure? I took my muffler off about 3 weeks ago. Also, what about a fuel pump? This be a cause?

What do you mean? You removed the muffler and now you have too much back pressure? What did you put in replace of the muffler? Break this down a little bit more. Fuel pump probably not the cause if you got low to medium mileage.

[black s13]

try changing your type of gas. i ran a full tank of 89 octane, and got 250 miles, and now just had 93 octane and got 160 miles, two tanks back to back.

[lotusdrift]

Originally posted by black s13
unless the filter is so restrictive that it bogs the engine, it cant really do anything. and no, all filters are not equal. there are reasons that you can buy a $5 fram filter or a $50 K&N, that do the same thing, but the k&n will clean the air better, flow better, and its reuseable.

running without a filter is fine, just no dirt roads, or small mammals. the hose that comes off the side is some ventilation thing or something, throw a breather on it and you should be fine, or go the good way, and buy a injen intake that has places for ALL the connections.

.

:bs:
First, have you ever bothered reading anything about k and n besides from advertisements. Their filtering power is much less than a regular paper (ie FRAM) filter. The funny thing is, as it gets dirtier it starts to filter better. After a few months you are filtering just as good as paper, but you get less flow. Anyways, don't spread crap you read from a commericial in a magazine, go read tests on oil analysis websites or something.

also, running w/o a filter is fine only if you dont mind replacing your engine. If you like your engine where its at, I would leave the filter where its at. btw, dirt is bad for the engine, in case you missed that lecture.


And as for premium fuel, it only refers to the octane rating. It doesnt burn any cleaner than any of the other lower octane fuels or have more additives. Marketing strategies would have you believe premium is better for the engine, but its simply not true unless of course you are having detonation problems.

edit: Didn't mean to come off as an *** if I did...But misinformation needs to be burned out of zilvia...

[black s13]

i didnt read anything from a magazine. i made my conclusions based on my experiences with my 240 and my honda. running the car for small amounts of time without a filter isnt all that dangerious, like i said, FOR A SMALL AMOUNT OF TIME. obviously runnign for extended periods without a filter will mess it up, or open the posibility for it to be messed up. about the gas, i was just commenting on the fact that i get almost double the miles on lower octane gas, it might seem odd, but its very true.

[RedlineRacer]

Originally posted by Dream240
What do you mean? You removed the muffler and now you have too much back pressure? What did you put in replace of the muffler? Break this down a little bit more. Fuel pump probably not the cause if you got low to medium mileage.

Yeah, I took the muffler off and put nothing back. I was planning on getting an exhaust right after I took it off. But, my dad is getting ****ed at me about buying so many aftermarket parts and not saving any money. So, I am gonna wait about a month and put a cat-back on. Let me try to explain what it is doing in a better way. Say I am in 3rd gear (does it in all gears) and I am cruising at 2500 rpm's and doing about 35 mph. Then I want to speed up and I give it some gas (not too much, but just enough to get me up to a higher speed somewhat quick). Then when I give it gas, it revs to about 5k rpms and I am still around 35 mph's. Does this make it more clear of what it is doing? I replaced my fuel filter, air filter, changed the oil and replaced my oil filter about a week ago. It kinda started happening when I did this now that I think about it. Anything that I could have forgotten about when I changed my oil to do this?

[AKADriver]

revs go up, speed stays constant = slipping clutch or broken automatic trans, no other possible answer.

[RedlineRacer]

Originally posted by AKADriver
revs go up, speed stays constant = slipping clutch or broken automatic trans, no other possible answer.

My car is a manual trans, and I will be cruising for like 5 minutes in the gear, and then decide to hit the gas. The clutch can still slip if it is already engaged? Factory replacment clutches are $90 right? From the post that Bill Roberts has been posting, I don't know if I can do the clutch change by myself. Damn...

EDIT: Also, I was testing to see if it was my clutch, and I would be in 5th gear around 50 mph, then drop it in 3rd and there would be no slipping.

[lotusdrift]

Originally posted by RedlineRacer
My car is a manual trans, and I will be cruising for like 5 minutes in the gear, and then decide to hit the gas. The clutch can still slip if it is already engaged? Factory replacment clutches are $90 right? From the post that Bill Roberts has been posting, I don't know if I can do the clutch change by myself. Damn...

EDIT: Also, I was testing to see if it was my clutch, and I would be in 5th gear around 50 mph, then drop it in 3rd and there would be no slipping.

The clutch can slip any time you hit the gas. This is because anytime you make the crank spin faster (hitting the gas),the clutch has to 'physically' keep up with it through friction. If the crank spins faster than the static friction that the clutch can generate, then its going to slip.

Are you rev matching when you drop it into third? because if so that would explain why the clutch isn't slipping.

Everyone has been giving you the correct advice, the only answer is a slipping clutch. Hope this helps.