Hi all
Just a query really, I know the stock manifold is good for stage 1a (what im working towards).
But does fitting a tubular manifold have any impact atall? I know the cracking issue, but does it reduce lag?
Have any impact on exhaust note/loudness?
free up any HP?
I like to know too, a side my side run on a rolling road would be amazing! I think they both pro's and con's. Just depends what your after.
most are going to say it is fine to run the stocker to over 300 as it is well designed
aside from the un-supported they crack issue, a brace from elbow exit flange to bell housing bolt stops that tbh
the 'normal' aftermarket mani with equal length runners will push the power gain above 5k revs with a loss below
you need a mani that replicates the unequal length runners same as the stock mani,
like the Tomei expreme http://www.frsport.com/Tomei-193086-...it_p_1538.html
or the H-DEV version,, 800 bhp did a similar for the CA,,
the Tomei will make a gain through out the rev range over the stock mani with same response and on boost point
back to back the longer runners make more at peak power at 5k+ revs but only slightly and at cost of a loss below 5k revs
less response and more revs to boost point or lag with equal length runners,
the stock thick walled mani muffles the exhaust note as well, aftermarket are louder, can change the sound
I have a long runner Apex mani on the 14a and that changed to more like a honda vtec yo sound as got on the throttle
and revved it out, but felt the power loss low down straight away
bracing the mani is essential for it to last, the stocker has a brace and the manifold is super strong,
it needs the weight of the turbo (about 15kgs hanging of side of engine) to be supported or it will be killing gaskets and cracking
I think they are worth fitting as the stocker is a bit poopy looking inside and small in places
just my 2p
I have the japspeed one fitted and the first thing I noticed was the raspy tone over 4k, happened when I fitted a miltek 421 branch on my zetec s too.
Looking to get a metal intake pipe fabricated to get some grunt back, hope to improve pigeon vocals too lol
I'm running 311 bhp on the stock manifold for about 6 years now. Changing it would be a waste of money unless I intended on going for more power. Changing it for this state of tune will rob a lot of low end torque. So save you money and keep the standard. There is no point changing it for changing sake. And there is no point in gain 10bhp at 7k revs and losing a heap of torque sub 4k where you drive 90% of the time. And personally I don't care if the manifold is shiny or not. "Function before form". The rule of thumb was always that the standard mani only really becomes a restriction above 300bhp.
Okay, so i wont be going past 300 bhp any time soon, ill just stick with the cast one
Thanks
When I swapped to tubular the powerband noticeably moved higher up the rev-range. The car found a noticeable amount of extra-poke at the top of the rev-range, but did lose a bit of mid-range torque as a trade-off. The car also sounded much better.
All-in I was very happy, but inevitably the manifold cracked so I changed back.
I plan to go Tubular again.
I'm also interested in this,im Currently running h-Dec stage 2a chip but still have have the stock cast manifold fitted.do people think it it makes a big difference to lack of torque you lose going to a stainless manifold?does it make the exhaust note a lot louder?
The stock cast manifold is totaly superior in all ways to the welded manifolds on a street car.
Keep it and be happy.
And to all the ppl that think the stock mani is restrictiv, couple of years ago, there was a SR20DET that put dpwn 460WHP on a stock manifold. thats 500 BHP + :-D
Perfect as my turbo will put me at about 480bhp tops. I'm going to run it easy at about 450bhp low boost. I'll stick to thr standard manifoldOriginally Posted by Galant_X
if you got everything in bits and pieces, i would give it a port job.
if you got everything in bits and pieces, i would give it a port job.
I'd like to see the same engine tested with the Tomei manifold, to see if it is better as they claim it is
not doubting the figures it makes,more that would be ideal for any gains or not at that amount of power
So does it make the exhaust note a lot louder or just a different tone?
imo not loads louder like going from stock exhaust to a 3 inch cat back,the thickness of the stock manifold muffles the sound slightly
thinner walled stainless pipes are louder so it will sound louder when you flour it,
the manifolds design can affect the exhaust sound out the back
tubular manifold normal length runner on CA18 in the 13 was just louder generally idle to limiter
the long runner apex mani on the SR20 changed it more like a honda vtec rasp (best way I can describe it tbh) at higher revs 4/5k+
the normal length manifold dont give the exhaust rasp sound at higher revs
As above, my car lost some of the muffled turbo note, and sounded more like an NA, especially at the top. I was very fond of the noise. Not that much louder.
...or get wardy88 to make you a bling one
See Daz's or Maff1991's build threads for pictures.
Last edited by Jonny Wilkinson; 13-01-2016 at 11:07.
Just been Looking at stainless manifolds as I'm thinking of buying one soon. I have noticed on a fair few of them even dearer brands the turbo flange is angled slightly,does any one know why this is, does the turbo elbow still fit ok? Even the likes of the apex type 2 equal length ones have th flange angled
AFAIK they are all interchangeable with the stock mani,and the stock or aftermarket elbow will line up
the only manifold I know of that caused fitting issues was the early XS power manifold and elbow combo sold together iirc
,if you fitted the manifold with out the elbow the exhaust D/P wouldn't fit/line up as turbo was angled
and would have same fitting issues with the xs power elbow used on a stock manifold as elbow is angled to correct the exhaust
...and Japspeed ones
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