lets when you do a pull from off idle (or load up on road in the sane gear/conditions) when it achieves half a bar or whatever you consider "on boost", not transient snap at high rpm but effective full throttle from low rpm, what rpm does it come on vs a turblown or fabricated divided manifold with similar sized turbo.

People are curious about the net effect of additional volume/surface area and potential valve face bypass to usable rev range.

I was hoping to trim a divider right to the face of a 60mm gate on a fabricated manifold myself down the track if it's doable.

 

Yes it very much behaves like a twin scroll manifold which provides smooth transient boost response, it's not snappy at all like it was previously with the old exhaust manifold which did not have the divided wastegate.

As far as doing a direct comparison to a Turblown manifold it's too early for that. I would say that information will become more apparent over the next few months once I have more alike combinations to compare.

 

Did anyone ever use the V band Artec manifold? I have a car in on which this got fitted. It mates with a 50mm Turbosmart gate and Tial 1.06 A/R single scroll housing with a gt3582r. So all mounted cold I smoke tested it for tightness and it was like 99.9% tight let it warm up and top up coolant etc and it already starts to leak (audibly) between the housing and manifold.

Bit put off buy that feature for now. I had covered the inside of the vband ring with ceramic paste so it would be able to clamp well wo fretting and the nut is tight. Ill let it cool down and see if I can give it a bit more tension on the ring.

ill tune the car next week so ill report how it spools and drive.

 

The housing you mention, not entirely clear if that's the wastegate or the turbo?

Can't say I've come across anyone here applying any sort of compound to a V-band flange face. If it's machined accurately and installed properly and not cockeyed in some manner, that should be sufficient for sealing

 

Yes that makes it so weird. Both faces where new and really nicely machined. The manifold comes with 3 rings which have a rim that precisely fits in a step in the turbine housing flange. I suppose depending on which housing you have you have to select the ring w the correct diameter rim. Before I fired it up it was also sealing properly. i can only think that either of both warped by heating up

 

Make sure the V-band clamp itself isnt hitting any of the external casting on either the manifold or the wastegate.

On my IWG EFR 8374 the Borg Warner V-band clamp would hit the casting of the exhaust housing as I tightened the Borg Warner downpipe V-band flange right next to the machined exhaust housing V-band surface.

I had to machine the exhaust housing rough casting AND machine the V-band clamp to keep the downpipe flange from de-centering with the exhaust housing when tightened.

The male/female V-band centering feature (that I love in higher quality V-bands) would force a gap at the V-band flanges as the clamp band hitting the casting forced a non-cocentric flange fit.

 

If you find the two machined V-band surfaces dont mate together perfectly you can lap them into a perfect fit.

Put some oil and 600 to 1000 grit sand (scrape it off a piece of sand paper) on the flanges, assemble the clamp fairly loosely and twidle the turbo and manifold back and forth for an hour or so (tightening clamp if it starts to feel looser).

Rinse and repeat if necessary.

 

Can understand the rationale for using rings, less than ideal in my book!

Turbo off time again I'd say. Something like a surface plate and feeler gauges, should tell if there's anything not quite right.

On conventional flanges, we have been using this for several years, but it shouldn't be necessary on well designed V-bands.

 

After putting the good o smoke machine on, the audible leak was not between manifold and turbine but between turbine and downpipe on the bottom of the flange.

Managed to strap it on the dyno and after having some weird issues with the PFC which in the end required a re initialize and start from a scratch on the tune as file I had made somehow got corrupt and failed too run the car properly are there the first results on spring pressure (7psi) in 4th gear. Figures are estimated crank hp so 30-45hp loss depending on rpm. run duration from 2500 till redline 4 sec
Specs:
13B w some weird looking streetport (looks a bit like alien ears)
Artec V band mani w 50mm Turbosmart WG w 7 psi spring
GT3582r w 1.06 single scroll Tial v-band housing
3' exhaust w CAT, resonator and Greddy muffler
550/1680 inj, Walbro pump
Greddy V Mount
PFC w 2.5 bar mapsensor

I'll hook the boost solenoid up and see if it wants to behave at 1 bar

 

Here it is w 1.2 bar, still a bit on the rich side probaly

 

Those ports look like they will be incredibly harsh to your seals. Do you have a particular reason for the shape?

 

The engine came to me like that. No hair on my head would get the idea to make a port like that. Initially the car came to just get tuned but when I fired it up it had only compression on one rotor. It had a dyno sheet in it saying 420 hp and it had the wire from the rear secondary injector broken and it also had just the stock fuelpump, just to name some of the issues

 

Has anyone thought about pairing a Turbosmart straight gate with the Artec manifold? My only thought is, it appears that when that style gate is closed, there will be a small air gap between the gate face and the divider in the wategate runner (to give ruum for the valve to rotate), but I'm not sure the mixing of flows matters at that point.

 

This is my planned use for the Artec I'm awaiting. Too many things backlogged at the moment to take it off the back burner though

 

Straight gate defeats the purpose of divided manifold. I cannot really see the attraction on a rotary application, sure packaging on log manifold 3/4/5/6 port runners but on a 2 rotor you would be back to twin gate, in which case all the cast and off the shelf fabricated manifolds are designed to package with ~90 degree gates.


I think people like using the new thing even if it's a step backwards in actual performance and functionality. I'd rather that current be going to fuel pumps, injectors and coils.

 

I guess that's my question. Does it actually "defeat the purpose" to have crosstalk all the way down a divided runner?

 

I missed the straight gate aspect, so yes I think the more overlap the engine has the greater the risk theres gonna be worse effects. Like for a PP or bridgeport id be more temped to go for a twin gate fully devided setup

 

I think you're assuming that I think it will be better, as well as my reasons for doing so. I make things, those things require controls, many of those controls are gate-kept by the manufacturers (or they were 3rd party solutions integrated into product offerings) - this is a 2 birds with one stone situation in that I know I want to use electronic straight gates on other projects as well as the fact that I'm not made of money and I dislike the current crop of under-supported H-bridge boxes offered.

 

Out of interest what is the reason you want to use electric straight gates? On this car w the 50mm turbosmart gate it regulates boost perfectly fine from 0.55 bar on spring and it makes 1.25 bar at 68% duty. So itll easily do 1.5 bar w more duty.

 

Mainly to play around with different boost and - more specifically - torque target strategies at the flip of a switch without the need for a pressure source (be it manifold or some other exogenous compressed charge). I've already been doing this with DBW throttling/control as well as (relatively) careful turbine housing and turbo sizing on a few engine platforms but I'm a nerd that likes to be able to do things on the fly rather than have to pull something apart to make the change and theres a bit of a 'been there done that' on the DBW side of things.

I could to the same with an electronic ProGate but like I was saying - I'd like to fiddle with the ESGs on a different platform as well.

 

Clearly your use case is pretty niche, and unless you are in desperate need to characterise flow behaviour of the straight valve you could use the E-Poppet for a better outcome, if you have characterised flow on similar sized butterfly DBW against angle for torque mapping you shouldn't need to repeat the excersise however, just confirm limits and linearity?

My comment was more for everyone playing at home. I admire you progressing your own control solutions. If I'm ever in a position to attempt an all out compound turbo system with very wide target control, well characterised straight and popped valve electric systems would be easier from a control and plumbing perspective than trying to run 4 port pneumatic or logic treed 3 ports to bridge the control range required and pressure rario balancing.

 

Id probaly use a efr91 w devided T4 internal gate and then use a electric actuator of choice, either aftermarket or from a OEM car. Only pita w these actuators and generally any electric Wastegate is the ‘kiss point’ of the valve. OEM Ecus have a quite complex strategy to be sure the gate is closed when it needs to be without having to continiously put a high duty to the DC motor. It involves re learning and temp correcting the closed feedback voltage.

 

All valid points that I already addressed - Except for the OEM actuator, which is down the line on things to do but certainly on the agenda.

 

I'm not certain it's as bad as it's made out to be - not the reason I'm planning on using one at all but certainly something interesting to take away if I can ever get caught up :|

 

When I datalogged my 60mm WG with and without divider up to WG poppet face it was from idle to 2,500rpm the purely divided wastegate really helped boost. Like double from 2psi to 4psi @2,000rpm, but no different above 2,500rpm.

It wasnt like decreasing intake restriction with velocity stack and 12" filter which helped boost build in low rpm and carried the spool curve all the way up to WG opening.

WG runner theory is interesting.
If you look at the early Trust/Greddy designs they tried to keep the two WG runners to a single WG the same length as turbo runners post WG plus Turbo exhaust housing. That way the exhaust pulses at the WG collector interacted at the same time as turbo exhaust wheel pulses.

Later they gave up on that and just put a single WG runner at the turbo flange.

I assume they found a turbo manifold that isnt cracked spools better than a cracked one with careful pulse tuning engineered in.

Likewise, I couldnt make a WG divider survive racing and gave up.