Ive just cured that flat spot I had around 4800rpm .... It was too much air entering the intake , the maf sensor was "maxing out" . I took the induction kit out and fitted the standard airbox back in last night, and straight away revved all the way up with no problems.
Ok it does sound abit like my vacuum again but I look forward to overtaking people again and powering away from them up to 6000rpm !!
I might look into a k+n panel filter ..... I'm gonna research into it and see if anyones had any problems with them..
hi, good to hear you solved it.
re the k&n filter. i have one. i took it out when i had all my emissions problems. a couple of the mechanics i spoke to suggested this was contributing (marginally) to the emissions as the oiled filter had some sort of detrimental effect on it. check first.
come to think of it, i think i may just pop it back in !!
J
the oiled filter can leave an oily residue on your maff sensor, hence the maff problems.
you need a dry filter like the apexi,
definatley wasn't the MAF maxing out as its good for 300Bhp, Rich's point about the oil on the filter is spot on imho
What do you suggest then ? obviously this has hindered my little ideas of nitrous oxide ..... I'm just glad I can rev the car up again for now... but I'll soon be thinking about some more power gaining mods s:twisted: :twisted: s:twisted:
use an unoiled filter like a trd or Apexi
Just chiming in from across the pond s:lol: :lol: s:lol:
Flat spotting is most often a dirty MAF sensor.
Also coud be a vacuum leak or a smaller than stock intake pipe.
As has been stated, if your N.A. theres no way the MAF is maxed unless something is wrong.
Quote from: "wts"Just chiming in from across the pond s:lol: :lol: s:lol:
Flat spotting is most often a dirty MAF sensor.
that what were saying Bill, the oiled filter is causeing oil particles to transfer into the intake air, thus further causing dirt to stick quicker to the MAF
If replacing the cone filter with a stock airbox cured the flat spot without you cleaning the MAF sensor then it is not the filter oil causing the problem. Once dirty the MAF sensor would require cleaning before it worked properly again.
IMO the likely causes of the flat spot are either incorrect airflow conditioning leading to the sensor giving an incorrect airflow result, or loss of the resonant tuning effect of the stock system (or both). I read on SC that someone had extened the over wheelarch trunking to get closer to the cold air sorce at the wing vent and noticably lost power. This would indidcate a tuned sytem at work. Perhaps Toyota engineers are more clever than some give them credit for?
Having chased a MR2 with a cone filter and being noticably quicker around those RPMs, I would suggest the stock airbox is a better idea.
Chris
If the tuned airflow theory was correct then there would be issues with everyone who's running anything other than the stock airbox, and we know that's not the case. I'm guessing it would also affect the TRD/Markiii pipe as well, which again it doesn't.
An induction kit gives a better noise but will give less power due to it sucking in hotter air than the stock solution, that's probably what accounted for the difference in your chase.
Quote from: "Ekona"If the tuned airflow theory was correct then there would be issues with everyone who's running anything other than the stock airbox, and we know that's not the case. I'm guessing it would also affect the TRD/Markiii pipe as well, which again it doesn't.
An induction kit gives a better noise but will give less power due to it sucking in hotter air than the stock solution, that's probably what accounted for the difference in your chase.
Of course drawing warm air into the intake is always a bad idea if youwnat power.
I think that the tuned airflow scenario would mean there are setups that will work and setups that wont. The SC contributor who lost power extending the wheelarch trunking demonstrated this. He had a stock airbox. Same for airflow conditioning, some will suffer, some wont. So not all aftermarket solutions would suffer.
A general lack of power could be high intake temperatures, a pronounced flat spot more likely an airflow conditioning or tuning problem. A combination of the two issues would be worst case scenario.
Chris
True enough, but there's a good few people running different setups on here that I'm pretty sure we can rule that out as being an issue.
heat is definatly not good, but running NA then the effects of the heat are negligable, i'm running intake temps of 70degC at the mo as i've got no IC to speak of following the mrs wacking it on a speed bump, interestingly i hardly notice it, however after around 7-8 miles the top psi that the turbo will make is 9psi rather than the origional 12psi
Quote from: "kanujunkie"heat is definatly not good, but running NA then the effects of the heat are negligable, i'm running intake temps of 70degC at the mo as i've got no IC to speak of following the mrs wacking it on a speed bump, interestingly i hardly notice it, however after around 7-8 miles the top psi that the turbo will make is 9psi rather than the origional 12psi
Heatoak as all the pipework warms up or the result of a squashed / leaky intercooler?
Chris
Quote from: "ChrisGB"Quote from: "kanujunkie"heat is definatly not good, but running NA then the effects of the heat are negligable, i'm running intake temps of 70degC at the mo as i've got no IC to speak of following the mrs wacking it on a speed bump, interestingly i hardly notice it, however after around 7-8 miles the top psi that the turbo will make is 9psi rather than the origional 12psi
Heatoak as all the pipework warms up or the result of a squashed / leaky intercooler?
Chris
as it it ripped the ram air scoop off and now the IC has no airflow
Talking about situating the induction kit so that it is behind the battery/next to left intake .... This is where I had mine.
Like I said it revs ok with the standard box on so I'll probably leave this on ....
PPE induction is the best kit going for the mr2
it uses an apexi filter, this the best choice cone filter in my honest opinion.
if you want like PPE then the green dyna twist is another viable option as it runs in a similar manner.