DIY manifold
#1
Senior Member
Thread Starter
iTrader: (5)
Join Date: Sep 2009
Location: Lompoc, CA
Posts: 577
Total Cats: 13
DIY manifold
So I have decided that moving to Albuquerque, NM at an altitude of almost 6,000 ft makes my already weak sauce JRSC even more full of fail. I am taking the plunge and building a turbo setup. I have a tig welder and an angle grinder, so I'm building my own manifold. I'll be using a TD-04 WRX turbo for a couple reasons. 1) My power goals are modest enough to use it 2) They are readily available 3) They are super cheap and 4) Teeny turbo means instant spool. This is just going to be a fun street car. I don't have any PS or AC to worry about.
I'm torn between trying to fab 2 different designs. The first is the basic log manifold made with weld-els and T's. The second is more like absurdflow's super amazing SS car art.
The log will be much easier to build, should spool pretty well, have decent power potential and the turbo is easier to install. However, the top end power may be limited, it flows a lot worse, and the DP is more complicated, along with potential heat management issues.
The tubular low mount should do everything better, except that it's much more difficult to fab and the turbo is not as accessible.
There in lies the question. Is the tubular low mount design really worth the added difficulty of building the thing, then having the turbo buried and hard to get to? Or something entirely different?
I'm torn between trying to fab 2 different designs. The first is the basic log manifold made with weld-els and T's. The second is more like absurdflow's super amazing SS car art.
The log will be much easier to build, should spool pretty well, have decent power potential and the turbo is easier to install. However, the top end power may be limited, it flows a lot worse, and the DP is more complicated, along with potential heat management issues.
The tubular low mount should do everything better, except that it's much more difficult to fab and the turbo is not as accessible.
There in lies the question. Is the tubular low mount design really worth the added difficulty of building the thing, then having the turbo buried and hard to get to? Or something entirely different?
#2
Elite Member
iTrader: (37)
Join Date: Apr 2010
Location: Very NorCal
Posts: 10,441
Total Cats: 1,899
I'd love to hear some responses on this as well from folks who have fallen down the DIY rabbit hole. I'm in the process of obtaining a used SR20 terbo for this exact purpose.
From what I've read, the low-mount log is pretty actually somewhat easy to fabricate provided you can clock the turbo. It gives you a bit less drama on the downpipe side and "can" make plumbing easier. Also keeps you clear of the heater lines and the MC. I'd suspect the coolant hose routing for the mixing manifold may be an issue. I'm not sure how much accessibility you will really need for the turbo, more like accessibility for other stuff?
I'm sure some of the more experienced members will come visit shortly and laugh at us supercharger guys discussing the merrits of turbo manifold design
From what I've read, the low-mount log is pretty actually somewhat easy to fabricate provided you can clock the turbo. It gives you a bit less drama on the downpipe side and "can" make plumbing easier. Also keeps you clear of the heater lines and the MC. I'd suspect the coolant hose routing for the mixing manifold may be an issue. I'm not sure how much accessibility you will really need for the turbo, more like accessibility for other stuff?
I'm sure some of the more experienced members will come visit shortly and laugh at us supercharger guys discussing the merrits of turbo manifold design
#3
you mention that a log manifold may limit top end power, but how much top end power are you really expecting from that little turbo?
honestly, I would do whatever you feel comfortable with for your first outing. don't bite off more than you can chew and have to get a bus pass like a pinko commie ***.
honestly, I would do whatever you feel comfortable with for your first outing. don't bite off more than you can chew and have to get a bus pass like a pinko commie ***.
#4
I've tinkered with the wrx td04's for a long time. Wonderful turbos. I'd go with the weld-el mani and keep it cheap/simple because that turbo won't exceed 240whp anyway, and your topend won't be anything spectacular anyway.
Go for the midrange kick which is what the turbo is good for, and enjoy it for what it is while saving up for a big boy setup for when you want MOAR BOOST
Go for the midrange kick which is what the turbo is good for, and enjoy it for what it is while saving up for a big boy setup for when you want MOAR BOOST
#5
Senior Member
Thread Starter
iTrader: (5)
Join Date: Sep 2009
Location: Lompoc, CA
Posts: 577
Total Cats: 13
I've tinkered with the wrx td04's for a long time. Wonderful turbos. I'd go with the weld-el mani and keep it cheap/simple because that turbo won't exceed 240whp anyway, and your topend won't be anything spectacular anyway.
Go for the midrange kick which is what the turbo is good for, and enjoy it for what it is while saving up for a big boy setup for when you want MOAR BOOST
Go for the midrange kick which is what the turbo is good for, and enjoy it for what it is while saving up for a big boy setup for when you want MOAR BOOST
As for power goals, I'd be pretty happy with 220 or so. I want an easy to drive, reasonably quick street car with sooper dooper spool and a fun power band. I'd just like some opinions on whether the spool/DP/?? advantages of the low mount are worth the added man-hours vs a log style. I'm fairly certain either one will reach my goals until I can afford a bigger turbo and a built block.
#6
If you go low then the 13t will need to be clocked which probably means the wg actuator needs to be remounted. I did it this way.
If you can get your hands on a nb stock European? manifold you can easily make a low mount setup for < $. ( like this one http://www.ebay.co.uk/itm/1808822926...=p5197.c0.m619)
AFAIK the coolant hose routing has to be altered for td04-13t low mount. (I had to shorten the mixing connector for the td04 where as the previous sr20 type turbo was ok.)
I would go with an equal-ish length set up. Easier downpipe, less heat and better suited to future upgrades than a log. Plus the difference in fab time for a log and low mount is minimal.
If you can get your hands on a nb stock European? manifold you can easily make a low mount setup for < $. ( like this one http://www.ebay.co.uk/itm/1808822926...=p5197.c0.m619)
I would go with an equal-ish length set up. Easier downpipe, less heat and better suited to future upgrades than a log. Plus the difference in fab time for a log and low mount is minimal.
Last edited by sturovo; 06-02-2012 at 02:50 AM.
#7
Senior Member
Thread Starter
iTrader: (5)
Join Date: Sep 2009
Location: Lompoc, CA
Posts: 577
Total Cats: 13
Well, I was inspired. If a low mount manifold can be built out of an old header and done that well, I'm sure I can do it with new shiny weld-els. I decided to do something like wayne_curr. That seems to be a nice compromise between easy-ish to build, low mount for all of its benefits, and flowing pretty well. So about $100 in materials from weir-tech and we'll see how this goes. One of wayne_curr's pics for reference.
#9
Senior Member
Thread Starter
iTrader: (5)
Join Date: Sep 2009
Location: Lompoc, CA
Posts: 577
Total Cats: 13
Yep, ordered everything but the straight section I'll need from weir-tech. I ordered a head flange, subaru 3 bolt turbo inlet flange, the turbo outlet DP flange, and 5 90* 1.5" bends. They should be here sometime next week. My initial goal is to do the 1 and 4 runner almost identical to Wayne_curr's and then attempt to make the 2 and 3 runner curve into the flow a little more.
#11
Senior Member
Thread Starter
iTrader: (5)
Join Date: Sep 2009
Location: Lompoc, CA
Posts: 577
Total Cats: 13
Well, all of my stuff from Weir-tech showed up today. Despite the absence of any communication from the company, shipping was super fast, especially considering it came from Canada. And the products seem to be top notch. He has another happy customer. Hopefully I'll be able to get started on this manifold pretty soon.
#13
I know I just posted this pic in another thread but posting here for posterity. Here is my super-easy take on the log, but actually has curved flow so pulses aren't banging into each other.
Side mount, SR20 T25, no modifications to car to fit. Gasses are divided inside to keep flow smooth. I have more pics in my original turbo build thread.
https://www.miataturbo.net/showpost....48&postcount=1
https://www.miataturbo.net/showpost....6&postcount=12
Side mount, SR20 T25, no modifications to car to fit. Gasses are divided inside to keep flow smooth. I have more pics in my original turbo build thread.
https://www.miataturbo.net/showpost....48&postcount=1
https://www.miataturbo.net/showpost....6&postcount=12
#14
Senior Member
Thread Starter
iTrader: (5)
Join Date: Sep 2009
Location: Lompoc, CA
Posts: 577
Total Cats: 13
The plan is to make it like Wayne_curr's mani that's post #7 up above. Except, I'm going to take a stab at curving the 2 and 3 runners towards the collector and merge them a little cleaner.
#15
I know I just posted this pic in another thread but posting here for posterity. Here is my super-easy take on the log, but actually has curved flow so pulses aren't banging into each other.
Side mount, SR20 T25, no modifications to car to fit. Gasses are divided inside to keep flow smooth. I have more pics in my original turbo build thread.
https://www.miataturbo.net/showpost....48&postcount=1
https://www.miataturbo.net/showpost....6&postcount=12
Side mount, SR20 T25, no modifications to car to fit. Gasses are divided inside to keep flow smooth. I have more pics in my original turbo build thread.
https://www.miataturbo.net/showpost....48&postcount=1
https://www.miataturbo.net/showpost....6&postcount=12
#20
I haven't checked parts lately but Ace was $6.33 each for 6 stainless schedule 40 weld els and IIRC the flanges were $25/ $12 so definitely less than $100 shipped for parts.
EDIT: $6.75
http://www.acestainless.com/butt-wel...-304l/l90-h4wn