exhaust manifold cracked !!

GTi-RLee

New Member
Hi

My janspeed exhaust manifold has cracked :x
right on the weld between tubes on square section to turbo and down the back on engine side. i have striped the manifold off to look for more damage.
the cracks around 1 1/2 inches long.
Iam debating on getting it welded up or to get a new one.

Whats peoples advise on this as i dont want it to crack again when fitted or to end up with some monkey metal manifold off ebay ??

Iam not sure how strong these manifolds are or if welding would just crack again ?
running 400hp now so think thats pushed it ??

Any advise would be much appreciated

Thanks

Lee
 

GTI-R Nath

New Member
what turbo have you got, if your turbo fits on the standard manifold put a standard one back on, since the standard one is allot better than a japspeed manifold, seen loads of threads about these manifolds cracking.
 

whytie

Active Member
I had one off those but never fitted stuck to standard as it's perfectly capable. Ends up more money than it's worth replacing gaskets and studs.
 
M

markwashington

Guest
As above, those japspeed manifolds are sh*t. If you want a tubular manifold there's a protech one for sale on the other site, it's £700 but that's alot cheaper than new. If you don't want to spend that sort of money, which you need to to get a decent tubular manifold, then buy a standard one and port it out, it'll take about 4-5 hours of your time, but it won't crack and should be good for up to 450bhp.
 

GTi-RLee

New Member
Its the T28 with T30 bits hybrid i think
So the standard manifold is the way folward without spending silly amounts of money then.
What is involved in porting these out then. and how is this done. and the standard manifold doesnt restrick compared to this crap ive got fitted does it ?
i have seen alot of threads about gaskets aswell. what is good gasket. ??
 
M

markwashington

Guest
Search "ported standard manifold" and you'll find all you need to do it yourself. The gasket you need is the s15 one, you can order it straight from Nissan, the part number is on the part numbers thread, but it's 1403675f00 just in case you can't find it. As for a straight fit, A standard manifold will be fine. When was the last time your car was mapped? As I'm not sure if changing the manifold would have any impact on the mapping, I don't have enough knowledge for that.
 

Spikey

New Member
I have welded and Re braced loads of cheap Ebay Manifolds. The main Problem with them is that the
Welds are not strong enough they only Skinny welds. And for the Design well I have not seen any Dyno Print outs
from before and after Fitting one so i cant really comment.
 
P

pulsarboby

Guest
heres one we did for our car

all you need is a dremmel, flexi shaft around 4 various grinding stones and as said 4-5 hours of time
you can match the ports to the head too easily enough
and if you want to go the whole hog you can have the manifold dipped afterwards
 

vss irvine

Well-Known Member
if you use carbide cutting bits you can take a hour off that time aswell, but it does take some patience.

at least you can fit and forget....
 

GTi-RLee

New Member
Thanks for advice guys

Thinking of going with the standard manifold and porting.
Will this effect the performance much,was running 396 bhp and only had the apexi avcr and safc tuned recently.
With costs of doing all this and hoping to get more hp soon. Is being tight and putting the standard manifold with costs of ported back on and having the costs of retuning a bad decision ?

Trying to work out really, that for the price of the cheap ebay tubular manifolds at 1 hundred and thirty pounds ,it should last me a good while.
japspeed one that cracked was fitted for 4 years and was allways running over 350 bhp ?

ummmmm . making decisions isnt my favorite things.
 

skiddusmarkus

Active Member
No need to pay someone to port it really, its easy to do yourself.I just sat in the back garden for a few hours and did mine using a dremmel and flexi drive thing like Bobby said.Don't think anyone has done any before and after tests but its one of those things thats quite satisfying to do and you can convince yourself its a benefit.
 
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