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-   -   Need some help finding after maf hose (https://www.seccs.org/forums/showthread.php?t=8785)

renosubby 2010-05-06 08:29 AM

Need some help finding after maf hose
 
So I have come to the conclusion my after maf hose is collapsing when I shift her hard or launch. I need something that will hold better then the gimmick one. Any suggestions? I have 2 clamps on it to stop it for now. But it looks ghetto!

Cory

sperry 2010-05-06 08:44 AM

The stock plastic one doesn't collapse. :p

But seriously, I never had issues with either my Samco or Perrin inlet pipes (that I know of), and the Samco one was really soft. But the for-sure solution is a hard-pipe.

Dean 2010-05-06 08:53 AM

I'm with Scott. Unless you have a clogged or restrictive filter, there should not be anywhere near enough negative pressure to collapse an undamaged/uncrimped silicone hose.

Take the air cleaner off and see if you can reproduce the problem. If so, it isn't the hose. If you can't, it is the filter.

Wait, 2 clamps where? Sounds like a leak, possibly in addition to a low flow filter, not a collapse if post MAF clamps fix it.

AtomicLabMonkey 2010-05-06 09:24 AM

"Need some help finding something" is the most vague thread title ever. Be more descriptive.

Now I've wasted even more seconds of my life posting a response. :rolleyes:

renosubby 2010-05-06 10:33 AM

Quote:

Originally Posted by Dean (Post 148775)
I'm with Scott. Unless you have a clogged or restrictive filter, there should not be anywhere near enough negative pressure to collapse an undamaged/uncrimped silicone hose.

Take the air cleaner off and see if you can reproduce the problem. If so, it isn't the hose. If you can't, it is the filter.

Wait, 2 clamps where? Sounds like a leak, possibly in addition to a low flow filter, not a collapse if post MAF clamps fix it.

I have 2 clamps on the after maf hose like in the middle of hose and one on the bend of the after maf hose closest to the inlet.

szucchet 2010-05-06 01:57 PM

i think kstech sells the aps hard inlet

knucklesplitter 2010-05-06 04:58 PM

Quote:

Originally Posted by szucchet (Post 148799)
i think kstech sells the aps hard inlet

Not really, but I did give him the Gimmick hose he may be having trouble with. Never heard of collapsing being an issue in any MAF hose. Also can't see why it would be when you shift or launch. *If* this happens it would occur at peak power where the peak airflow happens.

What are the symptoms? Did the clamps fix the problem?

Samco makes a much beefier one now.

knucklesplitter 2010-05-06 04:59 PM

Quote:

Originally Posted by sperry (Post 148774)
The stock plastic one doesn't collapse. :p

But seriously, I never had issues with either my Samco or Perrin inlet pipes (that I know of), and the Samco one was really soft. But the for-sure solution is a hard-pipe.

The stock one will not work with his intake.

A "hard-pipe" turbo inlet generally still uses an "after-MAF" hose. The APS comes with one, and the Agency Power version needs one (the Gimmick is a popular choice), unless the intake goes all the way to the inlet pipe (which his does not).

sperry 2010-05-06 05:05 PM

Quote:

Originally Posted by knucklesplitter (Post 148815)
The stock one will not work with his intake.

A "hard-pipe" turbo inlet generally still uses an "after-MAF" hose. The APS comes with one, and the Agency Power version needs one (the Gimmick is a popular choice), unless the intake goes all the way to the inlet pipe (which his does not).

Wait, we're not talking about the turbo inlet? We're talking about the tiny length of hose between the MAF and the turbo inlet?

I can hardly believe that hose could be collapsing in any manner that would affect performance. Maybe, just maybe, at high RPM it would distort and possibly screw with the MAF readings a little bit because it's dirtying the airflow over the MAF itself. But I highly doubt this is screwing with shifting/launching.

Cory, what sort of evidence do you have that makes you think it's the after-MAF hose? I'm wondering if we might be able to come up with some other culprit... maybe the BOV is causing compressor surge or something?

Dean 2010-05-06 05:28 PM

Again, I am with Scott. Even if it was thin wall rubber or even inner tube thin, that short section of hose properly sealed and clamped tight at both ends is unlikely to deflect enough to do much of anything to engine performance.

There are lots of narrower points pre turbo that constrict flow more than that could. Unless you can put your hands around it and squish it to the size of the turbo inlet or smaller without pulling loose, I don't see how it could be the culprit, but what do I know?

renosubby 2010-05-11 03:22 PM

Quote:

Originally Posted by Dean (Post 148819)
Again, I am with Scott. Even if it was thin wall rubber or even inner tube thin, that short section of hose properly sealed and clamped tight at both ends is unlikely to deflect enough to do much of anything to engine performance.

There are lots of narrower points pre turbo that constrict flow more than that could. Unless you can put your hands around it and squish it to the size of the turbo inlet or smaller without pulling loose, I don't see how it could be the culprit, but what do I know?

I can... the thing is very easy to sqeeze together with one hand... I found a APS after maf that is re enforeced better... only other thing that i can think of is i might need a better flowing filter. but I will try this out tonight.

to let you know what happens is on pump gas if i launch the car it happens around 5800-6000. So i have about 20 psi and it drops to 13 ish at the point it does this....then if I shift hard say right after it it does it all the way through 2nd at 4-6 psi. Then if I shift to third it will be closed for part say to about 5800. then opens up and it never happens in fourth gear ever.

If im on race gas I can go from a roll in 1st or second and it collaspes about 5500 in each gear!


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