Borg Warner EFR Series Turbo's V 2.0

[GTSBoy]

1 hour ago, Lithium said:

So this divider extends to the face of the poppet, and there is a full seal between manifold and gate.  Any imperfection there is enough to completely screw any advantages of having a divided housing?

 

It would want to be pretty close fit to not leak through to the other half of the manifold.  Remember the peak pressures associated with the exhaust pulses are rather high.  You can move a lot of gas through a small hole with a high delta P.  Move enough gas and you rob pressure and energy from the pulse that was supposed to go to the turbine.

On the face of (no pun intended) that divider in your picture looks like it should go close enough.  But there's bound to be a large number of such manifolds that weren't made that way, that could lead to poor enough performance for the reputation to be founded.

[usmair]

Here's my manifold if anyone is interested.

Told CRG it was for a twin scroll and they made it accordingly.

My lag could be attributed to the gate being too big. Big old tech 60 mm Tial was off my old setup so may not be ideal size.

Too much off an expensive exercise to change it over a hunch so it's staying put I'm afraid.

[discopotato03]

My take with external waste gates is that the only sure fire way to get 100% sealing is to use 2 gates . I think relying on a divider that varies in temperature is a bit optimistic . With two gates , everything else right , the sealing point is the popet vave on its seat so if it works properly the only exit is via the twin nozzles .

No offence but I don't agree with acoustics and turbo exhaust manifolds . Different story with NA engines but they aren't trying to accelerate exhaust gas pulses into a spinning turbine wheel . Like was discussed here years ago the idea is to have each cylinder blow down into the split scroll with the least pressure ahead of it ie high to low .

The manifold runners are grouped to have two or three runners (I4/I6) set to have the other one or two cylinders not blowing down so the exiting gasses have the least resistance on their way to the blades . An I6 is a good example because the firing order is 153624 so front/back front/back front/back grouping makes it easy .

Obviously Nissan used this to good effect with the RB26s separate 123/456 manifolds and two turbine housings/waste gates . No chance of one group leaking to the other north of their dumps .    

[GTSBoy]

12 minutes ago, discopotato03 said:

No offence but I don't agree with acoustics and turbo exhaust manifolds . Different story with NA engines but they aren't trying to accelerate exhaust gas pulses into a spinning turbine wheel . Like was discussed here years ago the idea is to have each cylinder blow down into the split scroll with the least pressure ahead of it ie high to low .

 

I think you missed the point.  I was taking a verbal shorthand by using the term "acoustics", but I thought I went on to make it pretty plain that the nozzle in the turbine housing is the effective end of the pressurised part of the mainfold.  Thereafter the gases have been accelerated up to turbine speed and there is no feeding back into the other nozzle and back into the other half of the manifold after that.

I otherwise also agree that there's little value in pulse tuning a turbo manifold except to gain the last half percent.

Having said that.....split pulse housings and manifolds by their very existence make a tacit acknowledgement that there is some value in keeping the the pulses apart!

[sneakey pete]

Well, looking at the pictured manifold of Umair, that's not really divided at all....

 

[Count Grantleyish]

Here's my manifold if anyone is interested.
Told CRG it was for a twin scroll and they made it accordingly.
My lag could be attributed to the gate being too big. Big old tech 60 mm Tial was off my old setup so may not be ideal size.
Too much off an expensive exercise to change it over a hunch so it's staying put I'm afraid.

Any pics of it mounted in the bay with turbo?

[Full-Race Geoff]

On 12/22/2016 at 8:44 PM, Lithium said:

So this divider extends to the face of the poppet, and there is a full seal between manifold and gate.  Any imperfection there is enough to completely screw any advantages of having a divided housing?

i can guarantee that divider is going to crack off and get stuck in the turbo or in the wastegate

[Lithium]

If it does it will be the first of his to do that! It would be a remarkable effort to get into the turbo, too.

Edited December 24, 2016 by Lithium

[MattSR]

On 23/12/2016 at 3:53 PM, GTSBoy said:

Having said that.....split pulse housings and manifolds by their very existence make a tacit acknowledgement that there is some value in keeping the the pulses apart!

100% spot on!

[Shoota_77]

23 hours ago, Lithium said:

If it does it will be the first of his to do that! It would be a remarkable effort to get into the turbo, too.

Yeah be a nice bit of upstream swimming to get into the turbo from there!  Regardless I don't see one ever coming adrift provided it's been welded right from the start.  

My issue with the split design is the fact that it's going to apply pressure to the wastegate plate cock eyed rather than an equal force across it. Whether that causes extra wear or leads to any issues I don't know but if space is not a limiting factor I would definitely go dual wastegate. There are definitely times where single would be a massive advantage predominantly for space, simplicity and cost (2 versus 1 wastegate).

Until someone does a straight back to back comparo we'll never know!

[Looney_Head]

that manifold Lithium posted is mine and was built by SInco in NZ, its going on a RB30 with a 8375 on it.

 

Mike from Sinco has made that manifold design for years and never had any issues. i went that route for cost vs performance. there is no proof that i have seen that shows twin gates will work any better than my 66mm gate setup like that.

[burn4005]

righto so I've convinced myself to throw the 1.05a/r 8374 I have sitting in my garage on the car and need to work out how the f**k you're supposed to plumb back twin gates without spending a billion dollars on fab work. I need to have the gates plumbed in. that Sinco manifold with the divider plate may be the go... anyone recommend someone in brisbane for exhaust/intake fab work? ive had bad experiences with several workshops in the past so i'm quite shy about who to go to.

I've found the following manifolds:

garage whifbitz: this looks ideal, but the design of the manifold has very different runner lengths and the cars sounds like a WRX. going from an equal length mines pipe, i can't deal with it. unfortunate because it looks very neat.

 

Sydney motorsport engineering/fullrace etc.: these have one gate out the front, but how do you route the piping back to the dump pipe from here? anyone have any pics of what they've done?

[

or this setup: unknown manifold (looks like 6boost) with both wastegate runners pointing backwards (by scotty on this forum I believe)

Edited January 8, 2017 by burn4005

[sneakey pete]

Top one not being equal length is bad.

Middle one wouldn't fit an efr 8374 on I'd hazard a guess.

Bottom one... Gate actuator of front one sits next to gate of rear one... Recipie for disaster...

The answer is.. I don't know. I would recommend jfab engineering in Brisbane for manifolds as he did a great job with mine, though it was iwg.

[Piggaz]

Why is the bottom gate position so terrible? Plenty is 6 boob manifolds getting around like that. 

I don't think there is an "easy and cheap" way out of this. It's a prick of a job, to do it right and neat takes time. Cough up.

[sneakey pete]

Just seems like it would be getting a lot of heat next to something that isn't designed to take it

[Piggaz]

An external gate not designed to take heat? It's bolted to an exhaust manifold and has exhaust gas running through it! It's gonna make sweet FA difference if you have two next to each other. If you're that worried, run the Tial MVS gates and run water through them.

[Dose Pipe Sutututu]

4 hours ago, sneakey pete said:

Just seems like it would be getting a lot of heat next to something that isn't designed to take it

LOL...what?

come on man

[sneakey pete]

Designed to have a large amount of heat going through one end of it doesn't mean it's designed to have that amount of heat radiating next to the other end of it.

The fact they offer water-cooled ones to me makes me think there's an issue with to much heat running through them. 

Guess I'm overthinking it. I should go read up some max heat specs on some gates

[Mick_o]

Oh dear seriously dude? ?

So the 900+ degree gas flowing in 1 end and out the other isnt going to heat it up? 

Or the fact its bolted to a flange on a manifold when there is no gas flowing through it will be more than enough heat for it to radiate through it.

Your gate or gates are ALWAYS going to be a similar temperature to your manifold as it's always going to be in contact with it and the exhaust gas. 

 

[Griffin]

I agree with Pete. The diaphragm will have a shorter life span. Thats why the top cap is somewhat isolated from the main body. Don't criticize the guy.