Should i get a fuel sensor (New Stage 2)?

[Pipps]

Is it still worth doing the fuel pump and sensor mods, while keeping a standard turbo?

[Midnightclub]

If you've got a clutch to handle the higher power then i don't see why not, if he made 163 on 17psi then i expect 175bhp would probably be possible, obviously a bigger turbo would always be better though

[Dum-Dum]

When you say 'with the right boost', above, do you mean that you would have needed an uprated turbo in order to really get the most of using an 1800 bar fuel sensor?

Nope, the 163bhp was on a standard turbo at just 21psi

Air and fuel needs to be in a ratio of 14.7:1 so if youve got fuckloads of fuel you need fuckloads of boost. Otherwise with loads of fuel youll just make smoke.

[Pipps]

When you say 'with the right boost', above, do you mean that you would have needed an uprated turbo in order to really get the most of using an 1800 bar fuel sensor?

Nope, the 163bhp was on a standard turbo at just 21psi

Air and fuel needs to be in a ratio of 14.7:1 so if youve got fuckloads of fuel you need fuckloads of boost. Otherwise with loads of fuel youll just make smoke.

Good point! I'll see what's the best map I can run with a standard turbo and keep everyone posted.

[Pipps]

076 injectors are a peugeot/bosch approved straight swap for your current items, the performance difference won't be noticeable, they're not a performance upgrade as such. Certainly nothing like fitting AMG tips to your current injectors like Bryn and some others did.

Would it be worth fitting 076 injectors at the same time as the r70 fuel pump and sensor?

If it's not so much a performance mod, is it more of a reliability mod? Or a smoke reduction mod?

What would be the benefit?

[Poodle]

It's not a mod at all, they're an equivalent replacement item, if there are any differences at all they will be minute. The only reason people go for them is because they are fitted to newer cars, such as the 307 HDi 90, so it's easier to find lower mileage examples without paying for a refurb.

[Pipps]

The Haynes manual mentions that the standard 306 fuel pump can create maximum pressure of only 1350nm:



Will this lower amount of available pressure impinge on the operation of the new fuel sensor once it is installed?

[Poodle]

As explained previously in this thread, and by pm:

Can i also highlight the comment he makes at the end of the first post: You need to know your fuel system is perfect for this to be worth it... Ideally you need to combine it with a R70 pump or better, as the standard items are not designed to generate that kind of fuel pressure and may well struggle to maintain flow at higher rpms/loads.

You will struggle to find a cp1 pump that can handle producing 1800bar on a regular basis, obviously they are not designed for this and the resulting increased stress will reduce the pumps life considerably. The R70 pumps people are using are not designed for this pressure either, both are rated to 1500bar only, however the R70 is more likely to be able to keep up with the injected volume required at high rpms, hence it's popularity as an upgrade.

Beyond that your only real option is to have a custom pump made, then you're talking serious money. Or learn to modify them yourself, from experience i wish you the best of luck getting the information required for that kind of modding, less accessible than mapping by a long shot...

[Pipps]

Thank you for the clarification. It will be interesting to see how the 1350bar standard 306 fuel pump responds to the uprated fuel sensor and Stage 2 remap from tb205gti.

I will keep you posted once I have fitted it and driven home tomorrow.

[Pipps]

Update: For the avoidance of any potential issues, I have ordered the 2.2 HDi Bosch fuel pump now too. Both to be fitted next week, and a tb205gti remap added. I will report back with how it goes.

[Mr Whippy]

Is it still worth doing the fuel pump and sensor mods, while keeping a standard turbo?

It's possibly worth doing.

Basically the 1800bar sensor lets you read much higher pressures, out to 1800bar vs 1500bar obviously.

The problem is the standard pump can't make high pressures AND high injections because the pressure is a function of restriction.

Think of it like a house tap.

Turn it on more as the rpm rise, and that is how the pump delivers it's fuel.

The injectors are like you putting your finger over the end. The less you let past, the higher the pressure it squirts out.


At low rpm (near high torque at 2000-2500 rpm) the tap is only half open, but you want BIG injections for loads of torque, so your finger is right off the pipe, and the final injection isn't really a squirt at all, more a dribble eventually.

If the fuel can't inject at high pressure, then it takes longer to get the amount you want in there. You can't inject too early otherwise you are injecting before the exhaust valves shut.
You can't inject too late otherwise you are pumping fuel in after the piston is past the top and it burns inefficiently and very hot (smoke, burnt turbines, etc)


Thing is, at low rpm where the tap is open only a bit, pistons move slower, and so you have a bit more chance to inject fuel any way.

Having an 1800bar sensor here is pointless because without a better pump, the rail pressure can't go higher really.

In theory on a stage 1 you could run higher rail pressure because injections are smaller, so the finger is more closed over the tap, so you get more squirty pressure.

Problem is you don't really need more fuel in a stage 1 as temps are already too high really. You can easily get enough at the 1500bar limit on a stage1.


So the main benefit is at higher speeds. The engine is running faster, injection amounts start to fall off too, so you get a slight gain here for more rail pressure.

Also as the speed is higher piston speeds are high and you want to finish injections sooner (a short duration)

So at maybe 4000rpm you can probably run a load more rail pressure, get better combustion and a bit more power, less waste EGT etc.


The 1800bar sensor is a worthwhile mod.

I've even sent people maps with it set for the 1800bar sensor simply because it was a cheaper replacement than the 1500bar sensor hehe.


The better HP pump in combo with it, well obviously you can turn the tap up harder everywhere and that just means you can run more rail pressure everywhere, and that generally means you can get more power by injecting more fuel in the same space of time as before.
Downsides are parasitic losses may be marginally higher so economy might suffer. For any possible gain you might get on one hand, you pay on the other.

From what I've seen the R70 doesn't have the de-activator for example.


All depends what you want I guess.

I say outline what you want, and then spec and budget it, and then do it.

If you want an 1800bar sensor then get one. But you can easily hit 175bhp/270lbft without one with a hybrid turbo that moves the torque curve further up the rev range (where the tap is open more to start with!)

However you look at it we see stage 2's making 290lbft or so on standard turbos, and we see hybrids make up to 180bhp on standard bits, so it's clear that a standard pump/sensor can run fuellings for 290lbft/175bhp or so. We just need the air! (and a good condition oem pump/fuel system)

Dave

[Poodle]

My R70 pump has the deactivator.

[Pipps]

The Stage 2 map file was uploaded today. The 1800 bar fuel sensor was fitted. The boost was increased to 18 psi too.

The performance is sensational! Noticeably more power in every gear. A great improvement over having just the FMIC. The car feels so much smoother and more balanced now.

I didn't notice any problems with fuel delivery - even when sitting at 3,500-4,000 rpm for extended periods. Would there usually be problems with that?

What should I look out for as a sign that the current fuel pump may be struggling?

[Ruan]

Out of interest - has anyone measured fuel return temperatures pre and post cooler?

I do wonder if it'd be a good idea to start using an uprated fuel cooler - it can't be doing the pumps any good...

[Poodle]

Sustained periods of high load would show up any issues, so say WOT in 4th gear uphill at 3500rpm. If it's not cutting out on you already then you're doing well tbh, really glad to hear it's gone well. Get a project thread up!

Have had that thought before, Ruan, for the very same reason. I'm going to have so many gauges lol.

[KrisB]

Sustained periods of high load would show up any issues, so say WOT in 4th gear uphill at 3500rpm. If it's not cutting out on you already then you're doing well tbh, really glad to hear it's gone well. Get a project thread up!

+1

You forgot to mention your Torsion bar that took all of about 15mins lol.

[Pipps]

I don't know how you adjusted the torsion bar so quickly mate, but that must be a new record!

[Pipps]

Here is a photo of the new fuel sensor, fully installed:



Pump is bang-centre, with Bosch part number on display. To the left is the cambelt, with the left half of the cover off.

[Poodle]

Was going to say, "that's the pump" lol. Have you had her mapped to suit yet?

[Mr Whippy]

Rail sensor and pump are not gonna get you any real gains on a standard turbo, since the standard pump and sensor can run enough fuel/pressure for the small turbo's capabilities.

You can argue that a bigger turbo (say a hybrid) that operates at higher rpm will even run more power on standard pump/sensor as the pump can spin faster and still make good injections at 1350bar or so out to 4500rpm for more power.

You only really NEED a pump/sensor to go over 300lbft at 2000rpm or 180bhp at 4000rpm kinda ranges. I've seen both those figures on standard pumps/injectors/sensors in isolation.

Only time you really need injections THAT short where rpm are that high, and IQ's so high, that you NEED the sensor, it's gonna be a pretty special tune imo (ie, over 200bhp)

Simply running high pressure for the sake of it probably costs in parasitic losses, higher fuel temps and other stuff, so possibly costing you mpg at cruise if you are not careful!

Hmmm

Dave

[Pipps]

Dave, thanks for your thoughts.

What turbo would you recommend for a replacement?

[Mr Whippy]

Hi Pipps,

I'm not 100% right now on turbo.

I have a few guys with K03 hybrids that are wanting their cars tuning soon, but several have bought existing kit so the detail of the spec is hard to know. I had experience with Chris Bryn's 306 with a GT15 and a K03 hybrid too, but again the exact spec is unknown but I'm fairly certain 180bhp is possible at the higher end, 3750-4250rpm kinda region on standard pump/injectors/sensor... torque might suffer a bit but that is no bad thing in my view.

I have one customer right now (HDi110 with K03) wanting to go hybrid and is specifically speccing up in the leanest possible fashion. Ie, cheapest route for the biggest gains to get enough flow/efficiency to run the HP pump/injectors at the happier end of their efficiency range.

It might not be for everyone but there is a glaring hole between stage 2 150bhp @ 3250rpm with a standard clutch tune, and 200bhp VNT jobbies that probably cost another £1500 to achieve over a basic stage 2.

If you could fit a hybrid to a basic stage 2 and run a standard OEM clutch with 180bhp @ 3750-4250rpm and 250lbft at 2750rpm you'd have something pretty nippy for, hopefully, not much cash more than basic stage 2.
You also get a lot more road speed per gear as it revs further with reasonable output which is exactly what these cars are crying out for.


Hoping to get this done in April/May time and then the spec can be shared, and if people want it they can order it all, fit it, and be reasonably guaranteed to hit the figures.
The only issue is gonna be HP pumps/injectors. If they are not healthy it'll show weaknesses, but so does a high torque stage 2 tune soooo...

Hmmm




Overall though, the turbo you'd pick depends on your goal. You kinda need to set a goal and then work back to see what you need and what is the best choice.

The best turbo for an otherwise standard FMIC car with a standard but good clutch *seems* to be something along the lines of a K03 hybrid that just plays to all the benefits of the standard bits!

Dave

[Pipps]

Hi Dave, I like the sound of your work for your customer with the HDi110 and the K03.

An OEM clutch with 180bhp @ 3750-4250rpm and 250lbft at 2750rpm sounds spot-on. I already have uprated pump and injectors, as you know.

Please drop me a line when you have this specific offering sorted this summer and I will pay you a visit for the K03 turbo and remap work.

[Mr Whippy]

The plan was to simply advertise the exact spec of the turbo, and show that a good reconditioned one with the right mapping on a good injection system would make good numbers.
Then I could simply do the leg work to get their ECU getting the figures offered.



Not sure if I'll be wanting to get too involved in the mechanical side as it's a mine field. Maybe some firm T&C's on what is offered.

Ie, if a customer has boost pipes blowing off, or their injectors or HP pump are not good enough, then I need to make sure they have a freebie chance to rectify and re-visit, but beyond that then a basic cost of £50/hr or something just to cover time basically.
Otherwise you can end up spending hours or days with a customer who tries to cut corners, and the cost of that adds on to the average cost and then good customers end up subsidising others, so they almost seem to be paying twice!


I'll be sure to share the dyno plots and k03 specs, some on-road videos and so on once everything is working!

Dave

[Pipps]

Sounds good. Please keep us posted.

[Pipps]

Out of interest - has anyone measured fuel return temperatures pre and post cooler?

Just by way of an update over 12 months later in response to your question, I can report that with an FMIC, a meaty Stage 2 remap, an 1800bar fuel sensor, and an R70 fuel pump, I am getting over 700 miles on a full 60 litre tank - which is something I was never able to achieve before. It's effectively 50mpg.

Of course, it's also easily possible to make a 60 litre tank last 350 miles.

[Poodle]

Ruan's referring to the fuel cooler, not the fmic, hence "fuel return temperatures".

It's pretty widely accepted that tuning a derv will increase it's economy as a rule, the improvement seen won't necessarily be anything much to do with the higher rail pressure.