another blow thru MAFS thread. and o2 sensors

[midnightsliding]

ok so i searched and came up empty handed. 1)!First whats the advantage of blow thru? i dont have a BOV or any cams so i wouldn't need to to smoothen out any idle issues.

2) would running blow thru and having no BOV be an issue? if i paced it on my hot pipe b/c thats the only straight pipe i have with out any bends.

3)what are the sept's to take when sealing you MAF to keep it boost friendly?

ok onto a new subject is their a cross reference # for a o2 sensor for a SII RB25?

[Carl H]

there is no reason to run blowthru unless you are trying to stablize cam lope idle and or run an atmospheric bov (located on the hotpipe, maf on cold pipe).running a blowthru system can make it behave similarly to a map system assuming you have an efficient intercooler...

[midnightsliding]

so it wont smoothen out the power band in anyway? i just wanted to make sure their was no real benefits to it besides havening cams and atmospheric bov

alright but i still need and o2 sensor. any suggestions?

[URAS]

you can actually tune more efficiently if you place the MAF after the cooler but the benefit is not worth the hassle if you dont have any idle or reversion issues.

i have done quite a few big cammed RB25's with the z32 mounted post cooler with no dramas.

[Carl H]

the only problem i have with mine is the fact that in the winter you can get colder than ambient intake temps with the maf placed on the cold side, this causes it to run lean.also for some reason my cooler causes water vapour to condense when its extremely wet out and will max the maf almost instantly when it hits it...oh well.

[Sil240]

Wait wouldn't cooler intake air going throught the MAF make you run even richer??Because the MAF works off of a Hot wire that measures the air by how much the air cools the wire??

I'm confused...

[midnightsliding]

I'm confused...

[Carl H]

sorry you are right, i was tired last night...but it still will run leaner in the winter, so ive found and richer in the summer.

[Sil240]

Because the air is denser. right

Since MAF is Mass Air Flow, it won't sense the density right?

A MAP sensor wouldn't be affected or would compensate for the different temp right.MAP=Speed Density correct?

[Carl H]

right again, but since its after the cooler the tempature isnt quite the same as engine bay ambient.this will cause it to read a denser charge than if it was in the engine bay...the maf is capable of reading tempature to an extent.

[Bronze MFP]

how can you have colder than ambient intake temps? air/air intercoolers will only cool to ambient temp assuming 100% efficency. only way you can get colder than ambient is to run a water to air, and fill it with icewater (assuming that is colder than ambient air in the winter...) or run a nitrous setup.

[Carl H]

k, well 30*f ambient isnt 30*f ambient at 65mph is it?they do have this thing called a wind chill factor .

[Bronze MFP]

bah! prove it, i wanna see equations

[Carl H]

fine be that way.

given:rb20det + large turbo + 240sx = fast carif fast car = car built and tuned by carl then car = awesome if tuned car + blowthru maf = awesome then awesome = well built car.

thus we can conclude that if fast car built by carl = awesome then carl = awesome.

[blurrbosi]

So why even run it... other than the atmospheric bov and cam issue...

[midnightsliding]

So why even run it... other than the atmospheric bov and cam issue...

still trying to find out if their is any other advantages. i was just looking to smoothen out my power band and i was wondering if this would help or not.

[Carl H]

a proper tune would smooth the powerband more than this would.

[eh?]

Because the air is denser. right

Since MAF is Mass Air Flow, it won't sense the density right?

A MAP sensor wouldn't be affected or would compensate for the different temp right.MAP=Speed Density correct?

An MAF will pick up a difference in density or volume. Either way will remove heat from the MAF's hot wire if you think about it.

[midnightsliding]

a proper tune would smooth the powerband more than this would.

yes it would im still learning

[Bronze MFP]

fine be that way.

given:rb20det + large turbo + 240sx = fast carif fast car = car built and tuned by carl then car = awesome if tuned car + blowthru maf = awesome then awesome = well built car.

thus we can conclude that if fast car built by carl = awesome then carl = awesome.

weak!

proof or ban!

[matafied]

bah! prove it, i wanna see equations

common sense

[midnightsliding]

figured i would bring up my old thread in stead of making a new one.

so what all is needed to do to prep the Q45 MAFS for blow through? and where can i buy and adapter thing to connect it to my IC piping?

[blurrbosi]

Still onto this huh? Well to connect the maf, I would just get (2) 2.5 or 2.75in silicone couplers with (2) 2.75in or 3in T-Bolt clamps. The cutting of the couplers would be up to you. Just dont buy the cheap china ones.

Please say you bought 272's!

[Coolwhip]

i believe he is asking about the inlet of the MAF where the 4 bolts would go (read: adapter plate).

[Carl H]

easy way is to grind the retangular part of the maf down so its completely round in and out.cheap and effective, then just get 90mm couplers and call it a day...might have the black plastic square on the top blow off sooo keep an eye on the silicone it does get old and then looses its adhesion.

[blurrbosi]

i believe he is asking about the inlet of the MAF where the 4 bolts would go (read: adapter plate).

LOL

DEET DA DEE

[OpeLok]

as far as the maf adapter plate is concerned, I just made my own out of 1/4" aluminum. Then weld a 1/2 or so piece of aluminum piping on top of it to bolt a hose clamp onto. Pretty simple and effective.

[Coolwhip]

i think someone needs to post pics of their blow through set up ::cough:: carl

[300Plus]

i think someone needs to post pics of their blow through set up ::cough:: carl

here are an old pics of mine. BOV on the hot pipe MAF where you see it...

I picked up a aluminum maf adapter on ebay and used epoxy between the two and around the electronics on the box part of the MAF.

[midnightsliding]

yeah im still into this. i have broken two Q45 MAFs now how i have them mounted behind my front bumper. theirs no room in my engine bay for a proper draw through set up hence why i had it be hind my front bumper. so i figured this would be a better route for now. my IC piping is not in any harm of getting hit so im not worried about breaking the MAF this way unless i really hit a wall good.

thanks for all the info i think i will do it carls way with grinding down the plastic. i could not really find any info on prepping the MAf but with this i should be set now. thanks guys.