Ever seen this?

[Topper]

Went on a trackday to Knockhill mid October, after the session, i started the car after having left it sitting, it sounded like a tractor. got her home, took off the heatshield over the manifold, to find this -

Got another stock mani (cheers Nicely :thumbs, couple of local SXOC guys came out to my house yesterday to swap it over, a little press on the manfold later: -

Havent heard many complaints about the stock cast mani cracking, just wondered if anyone else had?

 

[elizium]

wow.. and I thought the aftermarket tubular ones were more prone to cracking ...

 

[meddler]

There was a thread not too long ago about a cracked manifold. Maybe just a bad casting.

 

[JEZ 8553]

Geez, thats not good!

So whats better then ? stock mani or a particular aftermarket ?

I know APEX do a reinforced mani type 1/V2 & 2/V2 but im not sure if anyone has fitted them on an S15 to see if they fit ok (not too near ABS like most from what ive heard ?)

 

[sushiming]

hope mine wont do that hahaha good that uve got it sorted now bud

 

[dns15]

it could be due by aftermarket exhaust system thats not mounted properly swinging around when u drive

 

[sillbeers15]

It is common to find hairline cracks on the stock exhaust manifold, especially on cylinder no.1. I had such an experience on my S14.

But I have never heard such a bad crack as shown....and aftermarket exhaust hold up better unless a bad knock from lowest point of front pipe due to uneven road surface and execessive lowering of car can crack a manifold! I've seen one.

 

[Nicely]

it could be due by aftermarket exhaust system thats not mounted properly swinging around when u drive

This is the cause of 90% of mani cracks. The support bracket which attaches to the front pipe/cat flanges is there for a reason :nod:

 

[ichi-go]

And they said stock manifold dont crack. dayum first time seeing one

 

[Topper]

Lets hope this new one lasts a bit better

 

[japmadlad]

yea paddy had a apex type 2 (I think) on his 15. Was not a good fit at all. now rwmoved due to snapped turbo bolt in it. so just put on the standard item again

 

[slammedmind]

its cast, they wont last forever mate. On any performance car ive owned the cast mani always seems to crack or restrict flow. 9 times out of 10 they crack due to vibration. The stainless mani's will eventually crack too. If you wanted a once off that would never break then mild steel is the way to go, wont look fancy but it will out last anything out there.

 

[meddler]

You can still break mild steel too. If the exhaust is not supported properly something will break sooner or later.

 

[Paddy]

mild steel?? holding on to an expensive turbo AND being subject to hot exhaust gas... i'd be afraid it would melt

my type2 used to turn bright red at high revs... well hot!
but its just too big... it hits the ABS unit, so i had to move it... also as japmadlad said... it tried to drop my turbo on the ground... pita!

i got more performance when i went back to the stock manifold

 

[meddler]

I have heard that the stock mainfold is very good up to about 400hp. Anything under that, don't bother.

 

[Nicely]

I'd say about 330.

The problem with the cheaper tubular manis is that they were designed for the S14, which has an ABS unit which is sat further back. A custom shield or even a double layer of ali glass blanket should be enough to protect the unit on the S15. Don't forget to shield the brake lines on the firewall too. They'll act as very efficient individual fluid heaters otherwise!

 

[Topper]

My stock mani no longer has the heat sheild from the side or on top of it, so i'll need to go a bit mad with some Ali glass material i have.