FRPP intake manifold...is this normal?

[JeremyH]

Okay checked mine out thoroughly today! It does it too! But its alot less. My rails dont actually move,( i do have aftermarket rails not sure if that matters) but the runners do bulge out a little, only under vacuum, after a quick rev. Under strong rev or wot it doesnt move at all. But just a small quick rev when it draws vacuum back to idle they bulge out slightly, probably about 75% less movement then what the op is experiencing. I have aftermarket cams and all the turbo piping so my vac at idle is only 15-16 in/hg. Under boost its rock solid and no movement.

It looks like under vacuum the engine is pulling down the top of the manifold which doesnt have much reinforcemnet and once full vac is acheived and the top goes back to normal or when you rev it, it makes the side runners bulge out slightly.


They tested it under pressure but looks like they should have done a little more testing under vac! Or it could be a quality control issue with the plastic compound used.

 

[06GTMustang89]

so are you returning yours or keeping it?

 

[JeremyH]

Keeping it, its not enough to bother me. But i can see the slight bulge only at a quick rev to like 2k then let off, other wise if u hold the throttle and rev to 5-6k it doesnt do it. And it doesnt move under boost. But i am curious to see what ford says about this and will be following this thread.

 

[06GTMustang89]

im definitely returning mine since its A LOT of movement and hopefully my new one doesn't move at all or moves a lot less like yours does

 

[JeremyH]

im definitely returning mine since its A LOT of movement and hopefully my new one doesn't move at all or moves a lot less like yours does

Yeah i agree with you there, have you contacted ford, i think it would be interesting to see what they say when they see your vid. Or are you jsut gonna try another one first.

 

[Blxcklist]

So now we have 3 blacks lungs eh....

 

[JeremyH]

So now we have 3 blacks lungs eh....

LOL, its almost officialy a disease now.

 

[Blxcklist]

Im willing to bet money they are all doing it.

 

[JeremyH]

Im willing to bet money they are all doing it.

I agree. Another thought, i do have a strut tower brace over top of manifold that is a little snug. That may also be keepin it from expanding as much. I will try to get a vid of what mine looks like and see if it can see the top of the manifold changing in relation to the stb going over it.

 

[TheKurgan]

Does it do it when the engine is cold ? This might give me a reason to open up my hood scoop.

 

[JeremyH]

Does it do it when the engine is cold ? This might give me a reason to open up my hood scoop.

Not sure, i went for a quick ride and my temps were at 190 when i did the test. However my intake manifold temp is damn near ambient if not cooler everytime i pop the hood, even the center of the strut tower brace stays cool to the touch now with the hood scoop mod.

 

[06silverbullet]

wow i feel bad for you guys the got the bum manifolds, it's never fun when toys aren't working properly.

 

[06GTMustang89]

wow i feel bad for you guys the got the bum manifolds, it's never fun when toys aren't working properly.

just a minor setback thats why i have an F150 for a dd...plus 90+ degrees in southern humidity its not that fun to drive the car now anyway...i just hope my next intake doesn't do this shit thats for sure

 

[Mustang30212]

it's never fun when toys aren't working properly.

Funny....I had a girlfriend tell me the exact same thing once!!! LOL

RH

 

[dalemllns]

i say keep it on there. thats shits tight. who else's car literally has a heartbeat? you DO!!

+1 for that... you crack me up dude LMAO

 

[06GTMustang89]

Funny....I had a girlfriend tell me the exact same thing once!!! LOL

RH

 

[ZmanM3]

First time I saw something like that.

 

[dalemllns]

ok I have the same intake and After seeing this I went and checked mine. It does move a little but not like yours at all. My rails stay solid and they are stock. But I did notice in your vid that you do not have the large vacuum line from the intake to the valve cover (driverside) installed. Why? I think maybe that is the reason yours is doing this. I would however like to know what the outcome of this...let us all know please. Nice Stang BTW

 

[06GTMustang89]

thanks...and im doing a breather setup so i have that blocked off as i did on my stock manifold...if the stock manifold can handle it then this racing one definitely should...but i could also put pressure on the runner where it bulges when the car is off with my thumb and i can see it move in..i have a bad casting no doubt

 

[Mustang30212]

First time I saw something like that.

.....and she said that too!! WTF...you guys know my ex-girlfriend? LOL

RH