Plenum Leaks

[Ben C34]

But then you can't get the injectors out on a neo. leaking between runners wouldn't matter. Another pointless option would be to get a machine shop to machine the base of the plenum for individual rubber orings. Then you will save money on gskets

I would just get another manifold

[AngryRB]

Yeah I don't really want this to get overly complicated, its a massive PITA cause was hoping to get it tuned

Cars been jerky and had a constant miss for the last year, pretty sure this was the cause so just want to fix it once and for all so I can ram some boost down its throat. hmm, might get new lower half runners and new OEM gasket and torque to exact specs and see what happens, theres no room to get a torque wrench in there so will have to put together out of the car this time then bolt it to the head,

if it leaks again ill just torch the car .. lol

[AngryRB]

got myself another manifold and have taken the old one off,

Anyone have tips here to ensure a tight seal on both manifold to head and plenum to lower runners?

this new manifold has been powder coated so should I sand paper that off at the flanges to create sanded surface or does it not matter? want to do this right first time so to speak...

use any gasket goo or leave clean and just assemble?

[scotty nm35]

You could take it to a machinist to machine the flange straight, or just slap on an oem gasket, sprayed in Hylomar and bolt it on... It can only leak a little.

[AngryRB]

picked up the OEM gaskets from the dealer today, asked the guys behind the counter and one guy said the manifold Is likely warped and to get it faced, the other guy said the OEM gasket wasn't designed for high boost and wouldn't handle more than 10psi and I should get a steel gasket made up..

Got me considering welding it or having some kind of steel spacer made up..

opinions??

[Ben C34]

people use oem gasket no worries. Check flatness. replace or machine if required. don't weld it. That would be weird.

[AngryRB]

took the manifold to the engineering shop and all the flanges are warped upto 0.5mm, and to have them faced is $480, that's for 3 facings

Is it normal to have this happen on an intake manifold, or maybe its meant to be like that and the rubber OEM gasket takes up the gaps?

[Ben C34]

That's a absolute rip! go somewhere else!

[Ben C34]

Definitely not normal. There is no way the oem gasket could seal those gaps. doesnt make sense that it warped, maaybe someone tried yanking it off and missed a bolt?

[AngryRB]

maybe it was overheated, the old exhaust manifold was warped but that's bit different, wondering now wether the cylinder head along the flange would be warped too, will get these bits faced anyway..

[Ben C34]

I reckon there is no way the inlet face of the head would warp.

[StevenCJR31]

$480 is an over the top price. . . suggest you get another intake manifold and get it checked

then fit it up using oem style gaskets

job done

[AngryRB]

Yeah that's what I thought, taking it too another mob tomorrow which have quoted 80-120 per flange, bought a second whole manifold few days ago and it too is warped, im going to stick with stock manifold because from reading forums it sounds like the most ideal design etc for a street car...

can anyone confirm, should I be using any gasket goo for the fitment or bone dry and clean?????? sounds like a silly question but this will be about my 4th time with this and its becoming a joke..

[StevenCJR31]

please yourself. ..maybe for reasurance use gasket cement, the bastard shouldnt leak then even with increased boost pressure

[AngryRB]

tried the hylomar today and its squeezing the gasket out when I tighten it up, what a b@#stard!

now the get the crap off..

[scotty nm35]

You only need a very light coating on the gasket, Hylomar still relies on a flat surface. If the flange is that warped that the gasket squishes out one side you will continue to have issues I think.

You could possibly try gluing a few sheets of sand paper to a thick pane of glass and using that to flatten it out, may take a while but I have seen it work on heads before. (bush mechanic style)

[Dose Pipe Sutututu]

picked up the OEM gaskets from the dealer today, asked the guys behind the counter and one guy said the manifold Is likely warped and to get it faced, the other guy said the OEM gasket wasn't designed for high boost and wouldn't handle more than 10psi and I should get a steel gasket made up..

Got me considering welding it or having some kind of steel spacer made up..

opinions??

10psi? really? I had 1.3bar going into the stock gasket, zero leaks..

if you're having this much issue, I believe you may have a warpped intake manifold as others have mentioned.

Hope you get it sorted soon aye? I know the feeling when shit doesn't go your way you just wanna burn the damn car

[AngryRB]

You only need a very light coating on the gasket, Hylomar still relies on a flat surface. If the flange is that warped that the gasket squishes out one side you will continue to have issues I think.

You could possibly try gluing a few sheets of sand paper to a thick pane of glass and using that to flatten it out, may take a while but I have seen it work on heads before. (bush mechanic style)

I tried scraping most of it off and still squeezed out, my old man suggested I just use the Hylomar and remove the gasket all together so im going to try that..

[AngryRB]

10psi? really? I had 1.3bar going into the stock gasket, zero leaks..

if you're having this much issue, I believe you may have a warpped intake manifold as others have mentioned.

Hope you get it sorted soon aye? I know the feeling when shit doesn't go your way you just wanna burn the damn car

yeah it does have a very slight warp which the engineering shop said was hardly anything and that it must be how im bolting it up, will see how I go today bolting it up without the gasket altogether,

fingers crossed

[StevenCJR31]

But then you can't get the injectors out on a neo. leaking between runners wouldn't matter. Another pointless option would be to get a machine shop to machine the base of the plenum for individual rubber orings. Then you will save money on gskets I would just get another manifold

leaking between the runners would matter as the runner from one would be robbing the intake charge from the other, hence why the gasket seperates one runner from the other