Has anyone tried this:
http://www.docrace.com/_products/13b/13b.php

It seems like a very good job..do we have any feedback for the company or the manifold itself?

 

never heard of them

 

Looks nice. I'm always surprised at people looking for new vendors for products like this. Guys like A-Spec, Turblown, and others have been supporting this community for years with good products, service, and their time answering questions on this forum. Why go anywhere else?

 

looks nice, i personally dont like wastegate setup. There on ebay. Also another manifold would be Nuken to look at. The reason to source other manifolds is price. In some people eyes it's not worth $1000 for a few feet of tubing and a few welds. EVERYONE has there OWN opinion of course. 4cyl manifolds are $1000, x2 tubing length or longer, and toons more welds... Its kinda like the 4 cyl world. 8 V8 weisco pistons used to be cheaper than 4 4cyl pistons.

 

I just came across it and cause it looked nice I wanted to take opinions from others more experienced on single turbo manifolds since i'm just a newbie at single turbo setup :-D

 

+1

 

does a-spec sell the manifolds seperately was always under the impression they only sold kits?

and is it really 1000 usd for just a manifold?

 

I saw that..I am looking at maybe trying it out...

 

looks nice at the first...

but...

thats no true twin scroll manifold... there is no seperation of both runners in the wastegate tube!

have a look at the fullrace manifold!
http://www.full-race.com/catalog/pro...oducts_id=1869

 

you can have twinscroll manifolds with single gates on them
HKS, GReddy have been doing it for years
twin gates allow better boost control and more efficient
exhaust dumping when higher boost isnt needed

the welds, materials, and construction of the DOC Race manifold is nice
we will be working on it with my brothers FD and then we will soon
be building three 2JZGTE Supras with the DOC Race twinscroll twin gate
manifold also

we have one customers Supra on FULL RACE so it will be a nice comparison
to have another car on DOC Race

 

why do people run WG feed pipes off at a right angle when there is room to feed off at a much cleaner angle??

 

That Doc race manifold might work well. Sometimes when WG placement is too close to the exhaust port you can run into issues if it is not in a direct path. I'm not saying that would be a issue with this manifold.

The fullrace manifold I'm not a huge fan of, I just don't like the front gate so close to the oil drain.

Fully divided manifolds are fully divided as long as the secondary runners join at the gate. Will it perform as well? Most likely the edge will go to a dual gate manifold simply due to flow. Running one 44mm gate will never flow as well as two 38's and certainly nowhere near two 44's.

WG area examples.

38mm equals 1133.5 mm
44mm equals 1520.2 mm
50mm equals 1963.1 mm
60mm equals 2826.9 mm

Just by looking at those numbers you can see two 38's have a good amount of more area than a 50mm and aren't too far off a 60mm the benefit is they will be more responsive to boost both by less mass as well as having a better valve to diaphragm ratio.

 

If it's not because of space limitations there should be no reason.

 

Well thats not really a smart idea for everyone. A good number of folks on the forum know how to size their exhaust tubes properly, length, etc for 'better than good' pulse scavenging.

Their manifolds may simply not fit the engine needs and might prevent it from reaching max potential. But I suspect those guys can probably figure out how to tig the manifolds on their own.

The main reason I've never bought an off-the-shelf manifold is for the reasons above.
But I suspect not many really care to max their engine breathing abilities.


...just saying - the manifolds mentioned may not fit my rotary-engine needs;