sturovo

Jonathan, it is pretty tight fit off the compressor for low mount with ps



The distance from the center of the manifold to the back of the ps pump is about 7.5"
The s4 type in low mount has 8.25" clearance so it is a bit easier but still some type of cheater or short radius bend is needed if going straight up off of the compressor.

sturovo

Next up, 1.6 flowish log.
(The turbo flange should be vertical and the overall width between flanges less than 90 mm.)

sturovo

Not exactly as per drawing but happy with result.
[IMG][/IMG]

Internals should flow better than a log
[IMG][/IMG]

Width of manifold less than 90mm means td04 compressor outlet clears frame rail.
[IMG][/IMG]

Compressor intake clears power steering pump. Turbo outlet is 60mm below manifold centre so downpipe is easy. Stock cooling and power steering hoses should fit without adjustment.
[IMG][/IMG]

sturovo

Would adding a baffle to the collector improve flow?
I read from here BEGi Miata Turbo Exhaust Manifold 1994-1997. T25/T28, T3 BEGi that

What height baffle would work? In my case I think more than half height would impinge on flow.

bronie thoughts?

thenuge26

iTrader: (2)

Is this for your car? Make it too big, since it's easier to remove material there than add it. Dyno. If it's too restricted, grind it down. Dyno again. Repeat.

sturovo

Steve, good suggestions but as meez no having dyno I resorted to my tried and trusted omnipotent trans dimensional ghetto logic.

I first tried a full size baffle something similar to the one in the Begi.
[IMG][/IMG]
My eyes determined it was was too big and would restrict flow more than direct it.

[IMG][/IMG]
I removed material a few times until I got a shape that looked like it would work. (Direct flow without restricting it.)

[IMG][/IMG]

This will go in my friends 1.6 who wants 50more hp and will keep stock clutch and exhaust. (Td04-13t @7psi no bov or intercooler, homebrew piggyback.)

SortaSlammed

with that reversible manifold, what was the hood clearance when in the top mount lay out? I would definitely be interested in a manifold similar to that but with out the reversible-ness and footprinted for a T25/28, if youd be interested in making one. your work has gotten a lot better since the thread started.

sturovo

The distance from turbo flange to the hood is around 9" in my 99 NB. (If I understand it is a bit less in NA cars, probably around 8". In any case there should be enough room for most turbos.)
[IMG][/IMG]

(Turbo in pic is some t2 flanged saab thing.) I made this manifold as a s4 replacement which is usually mounted the other way round. [IMG][/IMG]

If I was making this manifold again I would offset the flanges more so the turbo would sit lower in top mount and higher in low mount.
and in other news, the new grass is getting there.
[IMG][/IMG]

buckbo972

That sure is some green grass

sturovo

I was surprised how quickly it grew as I set it only about 3 weeks ago These guys were a big help!

alphasaur

thats a big ******* dude

and your work is inspirational, I want to try fabbing now

sturovo

Chris, the kind words are appreciated.

Should I run these?

sturovo

I started making another flowish log, this time for a 1.8


There is enough room for a wrx td05-16g without messing with the frame rail.


I tilted the turbo slightly off vertical to make the downpipe even straighter but there is tons of room in any case


Random shot showing how I sorted out coolant return/mixer connection for use with lowmount t25/28 setup

sturovo

I got asked some questions about the flowish log set up.

What turbos?
T2 flange or subaru 3 bolt should work using this flange


Is there room for a downpipe?
Here you can see there is lots of room. (The bend radius on the downpipe elbow id 1.5d x 70mm, much better flowing than 1.25d pipe.)





What material is the manifold made from?
Mild steel flanges with mild steel or stainless bends. Heavy wall stainless bends are probably overkill given how short and sturdy the runners are.


Random, I found a local supplier for 2 inch steel braided 10 bar hose. It should be real easy to route the compressor discharge to the throttle when no running an intercooler. (It seems it would be also straight forward to run an intercooler under the rad.)

FAHREN

I'm enjoying the progress of this thread, subscribed.
Keep up the good work! Thinking about taking orders from the public yet?
have any of these manifolds been installed/tuned/run for an extended amount of time?

sturovo

Thanks Eric, so far it just a hobby but possibly soon I would like to offer a robust inexpensive 180 hp'ish kit.
A few of the manifolds/exhausts I have made have been run for months/years and have survived ok but this is expected as here there is a long winter when cars sit in garages and also there is no accessible track to easily destroy your car at
I guess the majority of cracked hot parts are due to thin materials and high thermal stresses.
I ran this in my car for the last couple of months and it performed well.


I just replaced with this setup which to test the basics of the kit I was thinking about.

sturovo

First few hundred km's down, so far so good.


No leaks as flanges didn't warp which is probably due using 9 clamp bolts and spreading the heat load during welding.
The narrow band bung should be rotated to give more clearance to the heater hose also I will use 5mm plate for the next downpipe flange as 10 mm makes no sense.

Running the TD04-13t without an intercooler and BOV at stock 7 psi waste-gate pressure is interesting. I pulled 4 deg of timing to get rid of slight WOT det (versus the inter-cooled td04 setup) but this is to be expected. There is a slight flutter from the turbo changing gears due to no BOV but it is not excessive as there is less than 2 litres of air at 0.5 bar between the turbo and TB. (I will try with a BOV valve also but I am curious if it can be eliminated for small volume low boost set ups with no adverse side effects.) The upshot of this is that boost has moved even further down the rpm range. Poke the throttle at 1500 rpm and it does a turbo diesel torque impersonation. Also, as it is low boost there is no problem holding power to redline. I will make virtual dyno plots over the w/e.


I was looking for a way to tie the rocker cover breather into the inlet.

Jae_Rex

Love the work and the updates. Motivates me to move forward and boost the Miata. Sell me one manifold.

sturovo

Thanks Jae. Which type of manifold would you like?

I finished the downpipe elbow for my friends 1.6 NA and test fitted it to his car. (75/65/55mm tying into the stock exhaust.)





It fits well on the exhaust side



and also on the compressor side clearing both p/s and coolant hoses



and siting high enough to make coming off compressor easy.



This is my friend Vlado.



Next plan is to replicate the setup for a NB which by the looks of it should be doable.

sturovo

We pieced it together and it fired it up! The turbo on low boost adds a big slug of torque from 1500 rpm which is what the owner had wanted.



With the extra power he might even get to use the retro stopwatch


How much power can be pushed through the stubby downpipe elbow and stock exhaust?
Hopefully it should flow better the similar Greddy bit as it is shorter and has less bends.



Also I am curious how creep will be when we turn up the boost. I made an attempt to make a bellmouth entrance.
(But with space being tight it wasn't possible to make it all that bellmouthy.)