Tomei Pon Cams S2 Rb25

[SKYMAGGOT]

4 hours ago, tridentt150v said:

Interesting, I only see a Stage III kit as their top of the rainge?

https://www.snowperformance.eu/en/water-injection/boost-cooler/turbo-gasoline

Can you show me where the Stage VI kit is hiding?

Cos I wanted to check how the rpm signal you quoted worked and what advantages it had over IDC.

I see it for sale a few places,

https://www.trademe.co.nz/a/motors/car-parts-accessories/performance/fuel-systems/listing/3829493793?bof=tEYhDDS4

https://www.nitrousexpress.com/Snow-Performance-Stg-4-Boost-Cooler-Platinum-Water-Injection-Kit.asp

 

[tridentt150v]

Ok, interesting cos Snow Performance don't list it.....and the nitrous express guys have an 'interesting' disclaimer attached the version they are selling.

Does the LCD display control module come with the Stage VI?

Too busy right now, but I need to check all this out.  See if apples are apples!!!

[Ben C34]

Don't get heaps caught up in the control side of things, especially The whole starts at certain boost then all in at next setting.

To get half the flow of a non compressible liquid through an orifice you need 1/4 of the pressure.  Not sure about you but I don't think the spray would be very good at a quarter of the pressure, considering how much they go on about high pressure pumps.

 

No manufacturer has said the flow rate at their minimum setting from what i could find, at a guess it wouldn't be half of full flow, if you are lucky it might be 2/3.

Injector duty cycle is the sensible reference point, but again my comment on the actual workable control range still applies.

 

Just squirt it in!

 

[SKYMAGGOT]

9 hours ago, tridentt150v said:

Ok, interesting cos Snow Performance don't list it.....and the nitrous express guys have an 'interesting' disclaimer attached the version they are selling.

Does the LCD display control module come with the Stage VI?

Too busy right now, but I need to check all this out.  See if apples are apples!!!

Not sure about the controller, haven't been able to find much about it, will do a bit more research over the weekend.

A lot of people seem to be using the AEM...

 

[SKYMAGGOT]

7 hours ago, Ben C34 said:

Don't get heaps caught up in the control side of things, especially The whole starts at certain boost then all in at next setting.

To get half the flow of a non compressible liquid through an orifice you need 1/4 of the pressure.  Not sure about you but I don't think the spray would be very good at a quarter of the pressure, considering how much they go on about high pressure pumps.

 

No manufacturer has said the flow rate at their minimum setting from what i could find, at a guess it wouldn't be half of full flow, if you are lucky it might be 2/3.

Injector duty cycle is the sensible reference point, but again my comment on the actual workable control range still applies.

 

Just squirt it in!

 

Yeah I don't know too much at this point but something like GTSBoy is saying, just spray as much as the spark can handle 

[tridentt150v]

If you disconnect the feed hose, then remove the jet from the manifold and reinstall it on the hose, you can check the mist spray volume and pattern by triggering the kit via one of the 1/4" boost lines [use a manual type tyre pump].  This should show you that the spray is progressive and changes with increases in boost.  So its pretty easy to check, I've done it....in fact  - from memory - Snow Performance asks you to do this to check that the system is working correctly once installed. 

Use boost [psi] because you can do this with ignition on, but motor not running.

It also helps if you have somebody looking at the monitor and telling you what the psi readings are as you go.  Use a bucket to spray the mixture into to save on a wet engine bay.

[Ben C34]

On 10/27/2022 at 2:06 PM, tridentt150v said:

If you disconnect the feed hose, then remove the jet from the manifold and reinstall it on the hose, you can check the mist spray volume and pattern by triggering the kit via one of the 1/4" boost lines [use a manual type tyre pump].  This should show you that the spray is progressive and changes with increases in boost.  So its pretty easy to check, I've done it....in fact  - from memory - Snow Performance asks you to do this to check that the system is working correctly once installed. 

Use boost [psi] because you can do this with ignition on, but motor not running.

It also helps if you have somebody looking at the monitor and telling you what the psi readings are as you go.  Use a bucket to spray the mixture into to save on a wet engine bay.

Are you measuring the volume or just looking at the spray in general?

It would be great to put a number against it, and also the pressure at minimum and maximum flow.

I dont doubt that it modulates, I just doubt how much it can modulate and how usefull a small window of modulation is. Especially when referencing boost I don't really see how that makes any sense, as 20psi at 4500 is a fair bit different to 20psi at 7000.

 

 

 

[tridentt150v]

No was looking at spray pattern and pressure.........but I didn't measure pressure - probably wouldn't be hard to do, just T in a pressure gauge.  But I didn't do it.  The spray pattern and pressure visibly increased with pseudo boost psi increases.

'20psi at 4500 is a fair bit different to 20psi at 7000'  not sure what you mean here Ben?  

The pump is electric so doesn't work on engine revs - but i don't think thats what you meant?

I assume that the pump creates pressure as a sliding scale, so if your trigger is say 8 psi boost then the pump might be doing say 60psi.......then if your 'all in' trigger is 14psi, the pump would say do 100psi, with a commensurate increase in delivery......these are outright guesses by me, just trying to explain as best I understand it.  So its your own thresholds/inputs to the control module that determine at what rpm you will max out the WMI system and where the best benefits are.  Personally I think having the system maxed out at 4500rpm means your settings/inputs are set too low for the 'all in' trigger.

I am assuming that the pump modulates its voltage via the threshold values [8 to 14psi]= modulated delivery.  The pump would have a voltage range it can use, say 8 to 14 volts.  Reading the catalogue this seems to be what SP state but indirectly...so I can't categorically state it as true.

if you were talking about using rpm as a trigger, I have no experience with that.  Mine uses boost psi and/or IDC.  Personally I can't see any real advantage in using rpm and some disadvantages -driving downhill , you wouldn't need as much WM when the motor is not under load is one I can think of.  But greater minds than mine may determine otherwise?

This is the latest catalogue:

https://www.snowperformance.eu/snow-catalogue2015.pdf

This is also why I questioned the OP on a Stage VI kit, Snow Performance don't list one, so I would advise some caution before any purchase.  Ask SP first, I haven't talked to them for years, but they used to be quite helpful and answered all my early emails, plus there was a SP/WMI forum with very knowledgeable people on there as well.

Hope this helps, not I'm really just a user who sees benefit, and have had no bad experience jus benefit while using.  The biggest issue I once has was the control module display didn't turn on with ignition, I just turned the unit and ignition off and turned on again all was fine...hasn't happened since.

Snow Performance might provide a more accurate answer.

 

 

[Ben C34]

I meant to get across the water methbflow rate required at 20psi boost and 4000 rpm is much different to 20psi boost at 7000rpm. So basing flow off boost is a poor choice , injector duty cycle makes the most sense.

 

 

But keeping in mind the fact you need to 4x the pressure to get double the flow of liquid through the jet, you very likely won't get a wide control window of water meth flow.

Pretty sure I tried to find out that specific info years ago and got no where, maybe I will email a few manufacturers and see what they say

[GTSBoy]

Yes, well this is where Joshua's preference for an injector based system makes sense. You can use the injector opening time to control flow while keeping the injection pressure high for all flows. It just hasn't been that easy (in the old days) to get injectors large enough and able to survive having water go through them. I suspect that the alcohol tolerant injectors of massive size are probably workable these days. And in an ideal world you wouldn't even use a dedicated controller and sensors. You'd just use the ECU to batch fire the water injectors based on inputs you already have, IDC and some suitable table.

[SKYMAGGOT]

13 hours ago, Ben C34 said:

I meant to get across the water methbflow rate required at 20psi boost and 4000 rpm is much different to 20psi boost at 7000rpm. So basing flow off boost is a poor choice , injector duty cycle makes the most sense.

 

 

But keeping in mind the fact you need to 4x the pressure to get double the flow of liquid through the jet, you very likely won't get a wide control window of water meth flow.

Pretty sure I tried to find out that specific info years ago and got no where, maybe I will email a few manufacturers and see what they say

I haven't got much info at this point, I spoke to a tuner that uses the AEM kit who said he usually gets the most gains in the mid range, which would go along with this theory based on psi, say it's starts spraying at 5psi then full at 12, at higher revs & as boost climbs you'd probably need to pull less/add more fuel than in the mid range

[Predator1]

On 25/10/2022 at 12:57 PM, BK said:

Broscience be incorrect there. E85 has superior spool because of the much increased exhaust gas volume from of how much extra fuel has to be added over 98. The extra 25 - 30% exhaust gas volume on E85 has a far bigger effect on the turbine than the higher egts on 98.

How much does the response shift to the left on the dyno? What size motor is yours?

[BK]

Nitto 2.8. From just a quick glance at the readings, on the spool up at full throttle in the 4 - 4.5k rpm range the boost is in earlier at around 400rpm earlier for 22psi. Power at that same 22psi level is about 20kw higher too. This is actually noticeably more exaggerated on the part throttle and on/off transient throttle inputs for the car at under 4500rpm.

Now as pointed out the extra 25 - 30% fuel on E85 might not equate to as high as 25% -30% extra exhaust gas, and granted there is definitely more timing in this area on E85 (3+ deg), but the difference is real and noticeable.

How much is due to timing and how much is due to E85 you can't answer as easily.

[GTSBoy]

22 minutes ago, BK said:

How much is due to timing and how much is due to E85 you can't answer as easily.

A little from column A, and a little from column B.

2 hours ago, SKYMAGGOT said:

a tuner that uses the AEM kit who said he usually gets the most gains in the mid range

Yes, at least partially, if not mostly, because in the midrange (or at least, near peak torque) you can't wind as much timing in as you'd like. Adding a spray allows you to pretend detonation isn't a thing anymore, and you can add timing.

[tridentt150v]

Also...thinking about the boost psi vs IDC for setting start and 'all in' values in the control module:

I think that many suppliers used boost cos it was easy plus it builds almost immediately = a good prompt start trigger.

But it is probably not as good as an upper limit value because full boost can be reached earlyish as the motor and power is still ramping up.  Maybe suppliers knew this but had nothing better....and its still the same for lower cost Stage 1 type kits.

But for a few dollars more you can add IDC to the mix.  And it makes sense to me that IDC - while slightly latent as a low trigger - is superior as an upper limit trigger where you don't want the WMI to plateau too early and the relevance of IDC has a greater bearing on engine performance.

I agree that direct injection of fuel + WMI + even air would be ideal, and if we had a clean slate and designed a new engine system you could do it all ....and joshua and I have debated this before.  But for general driving with occasional bursts, and even for some track work, the methods we are stuck with re WMI works fine.

 

 

 

 

[Ben C34]

From snow perdirmance email response.

 

As far as the volume the pump outputs at the start setting and the voltage supplied from the controller are things you’ll have to get a multimeter and test/ flow as that is the information we don’t offer to give out.

 

 

To me normally if information isn't handed out it isn't favourable information......

 

I'm for water meth injection, and if you choose to use a variable controller that's cool. Just want it to be realised that the control range is likely so narrow it way as well not exist.

[SKYMAGGOT]

16 minutes ago, Ben C34 said:

From snow perdirmance email response.

 

As far as the volume the pump outputs at the start setting and the voltage supplied from the controller are things you’ll have to get a multimeter and test/ flow as that is the information we don’t offer to give out.

 

 

To me normally if information isn't handed out it isn't favourable information......

 

I'm for water meth injection, and if you choose to use a variable controller that's cool. Just want it to be realised that the control range is likely so narrow it way as well not exist.

I far from know anything but maybe you sort it with injector sizes & it may be a case of you'll probably spray as much as possible in the mid range and end up with proportionately less in the top end whichever way it's controlled?

[GTSBoy]

12 minutes ago, SKYMAGGOT said:

I far from know anything but maybe you sort it with injector sizes & it may be a case of you'll probably spray as much as possible in the mid range and end up with proportionately less in the top end whichever way it's controlled?

I think you're missing the point. There are no "injectors". There are just nozzles.

With injectors, the flow rate depends on the pulse width. The pressure remains high at all times. Atomisation quality depends primarily on the pressure. Low pressure = poor atomisation. High P gives better atomisation.

With a nozzle, flow rate depends only on pressure. And, as Ben says, with an incompresssible fluid (ie, pretty much any liquid, including water and meth), the flow rate rises as a function of the square root of pressure. Ie, if you double the pressure, you get 1.4 times as much flow. Or the other way around, if you want double the flow, you need 4x the pressure. If you want half the flow, you only need 1/4 the pressure. (And that's where things start to look grim).

Consider what this means for the range of operating pressures you need to cover the flow rate range you want. So, if you were wanting, say, a 10:1 turndown ratio on flow, then you'd need a 100:1 turndown ratio on pressure. What does that look like? Well, your typical pump that you might have available for pumping water in a car (like a fuel pump, or something like one that can live with water in it) can really only manage to produce a few bar of pressure. Maybe 10 if you are very lucky. So, assuming you size that pump and the nozzle to deliver all the water you need at 10 bar, then by the time you are turned down to about 1/3rd of that flow rate you are only getting about 1 bar of pressure on the nozzle. And, atomisation will really suffer below ~1bar. (And, you also need to add your boost pressure on top of that, so you probably lose a bar from the whole operating range anyway, meaning that the pump is actually going to need to deliver at about 2 bar to give 1 bar nozzle pressure into the boosted air.) So what that means is that you will struggle to get better than about 3:1 turndown ratio, and I'd suggest that most systems' pumps wouldn't deliver even 10 bar, so you might find that you've got more like 2:1 turndown.

Whereas, you fuel injection flow rate turndown is >>100:1 (from idle through to full power) and the turndown just across the rev/power range where you want to inject water is probably at least 5:1. If you want your water to scale with "demand" (where demand is broadly equivalent to engine load, ie fuel injection quantity), then you're not going to be able to get anywhere near it with just a pump and nozzle. You end up having to over-deliver at the low end in order to maintain atomisation quality. And.....the general experience is that that's not really a problem.

The only other thing you can do to sidestep this is to have multiple nozzles and stage them in. You can multiply whatever turndown range you fundamentally obtain from a single nozzle by 2, simply by having 2 such nozzles. 3 for 3 nozzles, etc. But staging them is a bit rough. It's very difficult to smoothly transition from "maxed out flow on a single nozzle" to "just above that amount, on 2 nozzles), because you have to both activate the 2nd nozzle's solenoid, and reduce the delivery pressure, simultaneously. It's not impossible, but it's far far more control system complication than anyone is really willing to put in. If you wanted to get that sophisticated, then you'd go down the pulsed injector/ECU path discussed previously.

[FiXtUrE]

Just put r33 spec rb25de sticks in, same spec/profile as aftermarket cams, you don’t need to upgrade your valve train etc.from what I have heard, aftermarket cams snap 99% of the time here in Australia. 

[Ben C34]

On 3/19/2023 at 8:23 PM, FiXtUrE said:

Just put r33 spec rb25de sticks in, same spec/profile as aftermarket cams, you don’t need to upgrade your valve train etc.from what I have heard, aftermarket cams snap 99% of the time here in Australia. 

I'm loving the trolling. Reasonably subtle, good stuff.