which is better? i was just wondering the thoughts here. i currently have a homemade mild steel manifold i made from weldman elbows from VP supply…
but i bumped into a REALLY great looking cast manifold that looks very well crafted. im just curious what kind of durability can be expected from cast manifolds, as if they can handle somewhere around 500hp and not crack or whatever i might pick this up fpr my next setup upgrade when i get a bigger turbo.
do it and you can weld it if it cracks
technically, and theoretically, an equal length tubular header flows better. in reality, cast manifolds work extremely well, flow how they need to, can take alota abuse, and perform. they take alota heat.
i cant speak for all cars/setups, but this is apparent on lsx builds. whether its rearmount, or front mount (stock manifolds turned around), they perform, and sometimes better. theres 1000+rwhp cars running stock manifolds and running 8s.
Cast FTW
Unless You are going with a tuned tubular. But that’s a whole nother debate.
Log Tubular < Log Cast < Tubular unequal < Tubular Split Pulse Equal
how the fuck can you rate a manifold for hp, it should be rated in flow charecteristics
fucking ricer marketing schemes
in the same way that You can rate a bottom end for hp.
Cast manifolds tend to be cast from well, cast iron.
Cast iron manifold
Pros:
-can be cast into many many forms
-take alot of heat
-can usually be fit into a compact area (ie 350Z)
-cheap to produce
Cons:
-cast iron radiates heat very fast, probably one of the poorest choices for a turbo manifold in terms of material but again it is easy to cast and cheap to use, hence the use of it
-Can crack over time
-Usually offer poor flow characteristics due to the casting process and compact and odd shapes they are cast in.
-generally lend to more back pressure and as a result higher EGTs…inefficient in terms of performance and should never be considered in an all out performance turbo application
Tubular manifolds:
When contructed from the proper materials and designed properly these offer the best potential for horsepower. Keep in mind that the material you construct these out of is crucial as this manifold is supporting the weight of a turbocharger and has to deal with engine movement in the engine bay and and exhaust hanging off of it acting like a lever arm.
Pros:
-Generally constructed from stainless steel, this material is a poor conducter of heat, important in that you want to keep as much heat inside the manifold to keep the exhaust hot and flowing.
-Can be designed to flow properly and merge thus offering less backpressure and ultimatly more useable horsepower.
-Stainless steel tends to be a much more forgiving material to the amount of heat soak, flex and general wear on joints etc when welded properly as compared to cast iron or mild steel (which should not be used)
Cons:
-Stainless steel has an expansion rate of about 50 times that greater than cast iron or mild steel
-If not braced properly taking into consideration where the weight is acting on the manifold and how it is going to move due to expansion, the manifold will crack with time
-Not the most compact designs ever… depending on how you look at this or the application that could be a good thing and it could be a bad thing
One thing to note about the use of stainless steel is that the thicker the material you use (sch40 or sch10 etc) the faster the heat will be transfered from it to the air. Thinner materials hold more heat (sounds illogical but its true) however need to be braced considerablly to deal with mechanical stresses.
Focusinprogress, if you are looking to make as much horsepower as humanly possible out of this engine or you are looking to run anything higher than 14lbs of boost then I would look into using a properly designed tubular manifold but if you are going to be running sub 1 bar, you could probably get away with a Cast Iron turbo manifold, you may want to spend the extra buck and send it for jet hot or swaintech coating.
ok, so basically a cast version of my current manifold would be better. cool. as long as it can handle the heat and such that 500 would make…i just thought i would ask cause IIRC DSM stock manifolds crack.
If you are looking to make 500 horsepower I would not consider a cast manifold.
Do you have a link to the manifold in question
wow, thanks don. if i have the cash ill be coming to you guys with the next step in build. i want to upgrade to a gt30r with a v-band housing, 3" turbo-back exhaust, and a electric cut-out. ill have to see how money is in the spring though.
manifold in question:
e-cut out sucks compared to a good exhaust, you shouldnt need a cut out if you run a 3" exhaust
yeah, first thing on my list though is an intake manifold. i think i blew the seal where the two halves are pressed together from the factory :lol:
well we are a dealer for cosworth…having used one they are bad ass
Is that a cosworth manifold i posted? or are you talking about another cosworth part? i got confused there
cosworth intake manifold
im gonna have to say no to that
look at the quality on the wastegate … the nearest bolt hole is WAY of center in its mounting boss … wtf is that ?
if they gant drill a bolt hole centered, i wouldnt trust them to use quality materials
same w/ the wastegate flange on the mani itself … 2 are right on the edge of the flange
i thought the cosworths were duratec motors ?
nicks zetec powered … will they swap ?
pluss from what i can find, the cosworth intake has the TB on the passanger side, theres no space over there on the turbo focus
i thought the cosworths were duratec motors ?
nicks zetec powered … will they swap ?
pluss from what i can find, the cosworth intake has the TB on the passanger side, theres no space over there on the turbo focus
the cosworth intake manifold is for the newer duratec equipped foci. wont fit my car. only two intake manifolds were ever produced in mass quantity for the zetec, the for racing(overglorified aluminum ported version of the stocker plastic one) or the Focus-Central…which was discontinued and costed like $900. so its DIY or port an older contour zetec intake manifold.