Turbo Conversion on 3.0 SC Winter Project

[kenikh]

Those are EFI injectors

[gavinc69]

Thats what I thought, earlier in the thread you can see CIs injectors and he was running around 400hp at 1.4+ bar.
Last pic was maybe as he was doing an EFI upgrade or something.

2.7 turbo?

[gavinc69]

I happened to watch a data log replay from a few months ago when I had the small IC on and noticed the boost reading the FrankenCIS unit is getting was lower than the reading on my boost gauge.
The boost gauge would show full boost (.5bar) by around 3k rpm all the time, data log was only showing .3 bar.
The two take there source from different locations, gauge from just after the turbo and FrankenCIS just after the throttle plate.
Now I know the original IC was small and know how a twin pass IC can cause boost drop so I'm assuming this accounts for the difference.
I've only been out once in the car since the big IC install and it certainly had more go. The boost gauge would read .4bar until about 3.5k or more and then hit 0.5bar.
Seeing as the gauge now takes its source just after the IC I'm assuming its now a more accurate reading accounting for any drop caused by the IC.
I haven't done any data logs yet to see what boost readings the FrankenCIS is recording but providing the weather is good this weekend I will be out doing just that.

Its a bit of a bummer now knowing I haven't even been getting .5 bar but at least I know now and can move forward.

May need to change the IC to a straight through type to get the flow needed
Still seems strange I get full boost at such a high rpm
My timing hasn't been fully configured yet, so that maybe be a factor, its on the to do list asap, lock the dizzy and get the FrankenCIS controlling the timing.

I have ordered and just received a boost control solenoid.
I've been reading up on the install which looks very easy, although there's yet more tuning to do after its install to set it up right.
Hopefully this should help things and allow more precise control of the wastegate.

[kenikh]

I also noticed that depending on the MAP sensor, they have different configuration profiles. My data logs were reading lower than my gauge until I calibrated my ECU to read my sensor correctly. The MAP sensor was reading vacuum at rest, so got it set up to read 1 BAR at rest. All good since.

[gavinc69]

Still looks like my CIS can't provide enough fuel at full boost, so today I shimmed the Fuel head.
Luckily I found a few new washers of identical size but a little thicker.
The original two washers look like 0.5mm each and my new washers look like 1mm each.
So I installed one of the new and one of the old, going from aprox 1mm to 1.5mm.
Haven't had the time to drive and log the data since but will do that asap and post results. If needed I can add more washers.








Info I found online for shimming the head :

15.1.7 Systems Pressure
This is the pressure that is seen within the system between the fuel pump and the metering head. This pressure is determined by the primary pressure regulator, situated within the metering head.
When the required pressure is obtained, the plunger within the regulator lifts off its seat and excess fuel is returned to the tank.
This system due to the nature of its operation will automatically compensate for different fuel demands under different conditions. For example if the fuel requirement is low at engine idle, the plunger will lift and return a greater volume of fuel back to the tank than when the demand is higher, when a smaller amount of fuel is returned.
When the engine is switched off, the fuel pump relay looses the coil negative signals that energise it and the voltage to the pump is removed: this subsequent loss of pressure will cause the primary pressure regulator to close. This action subsequently blocks the return flow to the tank and helps the accumulator to maintain pressure in the system.
The systems pressure is determined by the tension of the spring reacting against the plunger, if a higher pressure is required, small shims can be placed behind the spring, changing it's effective length and increasing the pressure. A shim of approximately 2 mm will increase the pressure by about 10 psi

[gavinc69]

Slowly added shims and testing the fuel pressure plus did some from 2K third gear run's.
Ended up at aprox 93psi system pressure.

Let the FrankenCIS do its autotune and looked at the logs after each run.
I also tried adjusting the Control Pressure.

General results are :

Doing all the above made no real difference.
It still going lean above 4500rpm.

So I'm thinking its either the single SC fuel pump can't keep up the pressure or the fuel head just can't flow enough fuel.

Before the bigger IC it was going lean above about 5500rpm so I guess with the more flow of the bigger IC its going leaner earlier.

I will get a 044 pump and install that first, see what happens.

I've been googling CIS / K-Jet boost enrichment for the last week to see what othrs have done.
It appears changing to a different fuel head, like that off a Porsche 928 or Mercedes V8 which has more follow is one option. You can also use the additional two fuel lines to run additional injectors if needed.
Or just installing one or more additional injectors in the intake before the throttle body.
I've seen a few people use a Porsche 911 CSV with an rpm or pressure switch.
Tickford even used this setup on a production Ford Capri (the Tickford Turbo) it fired the extra injector towards the charged air to aid the mix :





One problem with that is possible uneven mixture to some cylinders and the CSV is just on or off so it can't start at say 20% and increase flow as boost rise's.

So how hard would it be to install a modern injector like from an EFI setup and use a modern injector controller to increase injector flow as boost rise's?

Something like this :

https://splitsec.com/product/aic1-a1l-additional-injector-controller/

Or can the MegaSquit side of the FrankenCIS control a 7th injector?

[kenikh]

Unmodified MegaSquirt can handle injector staging, if memory serves correctly. This would mean you could use it for a 7th injector. I think an injector upstream of the throttle buddy for high rpm usage is a good idea that I've not seen anyone try on a 911/930. Given that injector will be fired based on load and rpm, the big concern of ignoring fuel before the TB should never be an issue. And firing upstream should ensure even mixture, too. Trouble is that the only surefire way to confirm the hypothesis is to modify an exhaust with 6 O2 sensors or 6 EGT sensors.

[pkabush]

Originally Posted by kenikh

Unmodified MegaSquirt can handle injector staging, if memory serves correctly. This would mean you could use it for a 7th injector. I think an injector upstream of the throttle buddy for high rpm usage is a good idea that I've not seen anyone try on a 911/930. Given that injector will be fired based on load and rpm, the big concern of ignoring fuel before the TB should never be an issue. And firing upstream should ensure even mixture, too. Trouble is that the only surefire way to confirm the hypothesis is to modify an exhaust with 6 O2 sensors or 6 EGT sensors.

Sure would be nice to monitor afr on each cylinder. To bad there's not a more practical/economical way. The 02 sensor bill would be a bit steep.

Seems like the Benz FH might be the ticket. Thanks again Gavin, for blazing down this trail. Cool stuff.

[kenikh]

Best to try this by process of elimination. It's either the fuel pump, fuel lines/injectors, or fuel head. I'd try them in that order. Add an 044 fuel pump and see how it responds. If no go, you know you'll need it anyway once you get the flow restriction handled. Then get a set of lines and turbo injectors. If still not resolved, you'll know it is the fuel head. But at that point, you'll be intro it for more than EFI...

[gavinc69]

There's guys running a single 7th injector and one that I know is running a 7th and 8th next to each other :


Single injector :


Double Injector :



Tsuter with the single injector has been running for over 60K miles, and DPHANS tracks his twin injector motor (2.7, twin turbo, 450hp).
Both seem to be reliable.
Plus it appears adding one or more additional injectors seems quite common after hours of internet trawling on the subject of enrichment on boost and adding a turbo to a NA motor.

I was also thinking of buying a spare set of SC intake runners and welding on some injector mounts to the side or just above the original injector on each runner. I've seen several 3.2 intakes that have had this done.
But I have no idea about injectors, what lb to use ect and I think I would need injectors that have a continuous flow like CIS instead of pulsing! plus the only controller I can find to run 6 injectors is the HKS AIC Si, and its well expensive.

I guess I could install 6 CSV injectors and run a Hobbs switch that would turn them all on at a certain boost pressure, but that would be a huge amount of extra fuel!
Although I could then use the FrankenCIS to lean out the original injectors.

I did think of O2 sensor in each exhaust outlet but again not cheap to do and a PITA, even if I did it with only one injector I couldn't make any fuelling adjustments, I would just know it was lean in one or more cylinders.

[gavinc69]

I've been thinking of a setup integrating a 7th injector.

The 7th injector would ideally fire into the charged air, so easiest to mount it on a corner.
But have it some distance from the throttle body to allow as long as possible for it to mix/atomise.

One thing is I have a BOV to atmosphere. I don't like the thought of a air/fuel mix being blasted out into the engine compartment! I don't know how much volume of air is released from the BOV but I would have to mount the BOV as far away from the CSV as possible I guess.

My current IC setup is just not going to work (a good reason to dump that twin pass).
So I will need to get a standard straight through IC which may in turn help with the .5 bar only being reached at high rpm from possible IC restriction.

So it would install a little like this :

[boosted79]

That 2.7 CIS twin turbo is interesting... Any more info on it like what turbos, cams, boost, etc?

[gavinc69]

Do a search 'DPHANS' he's posted quite a bit of info on it.

[gavinc69]

Bosch 044 pump should be here by the weekend, hopefully will get enough time to fit it and see if this helps to keep the system pressure up through the rev range.

The company that rebuilt my old 930 WUR also does the Fuel Distributors. They can rebuild my FD and get it to flow 25% more fuel, for £500.

Just waiting to see if they will tell me know what they do to get the extra flow and also if they have spec's comparing against a 930 FD. Be interesting to see.

[RarlyL8]

To get more flow on the Euro (-037) Fuel Distributor you simply turn it up. To get more flow on the USA (-145) version you must modify with a new lower housing. The USA version will then have higher capability than the modified Euro.

[gavinc69]

These are the spec's I've been given :

930 turbo fuel distributor flows 300 cc/min.
1980 sc fuel distributor flows 180 cc/min.

This will be for EU engine's.

My FD can be modified to flow between 230 to 260 cc/min.

Will that be enough?!

[pkabush]

I'm far from an expert in this arena but, it would seem to me you'd be better off spending your $ on a higher flowing F.H. You could sell yours to offset or even cover the cost.

[gavinc69]

044 on




As per normal what you think will be a quick job takes most of the day hahaha

The original pump's electrical connections where small = positive and big = negative, but for some reason Bosch have decided to reverse this on the 044 meaning you need to cut the original electrical ends off and fit new ones (supplied with the pump) in reverse.
Also had to then lengthen the cable's a little as cutting the ends off meant that now they didn't quite reach.

Any way it all went on ok.

Removed the extra shims from the FD and went back to factory system pressure to stat with. Car started perfectly. No fuel leaks that I could detect.

Started shimming the FD again and checking the system pressure.

When I had the max amount of shims in with the original pump I was getting aprox 93psi, with the 044 and the same max amount of shims I'm getting over 100psi,
So I removed the two very slim factory shims and it dropped to 90psi.
That should be good enough for testing to see if there's any difference with the new pump.

Run out of time at this point so I'll have to see what the results are tomorrow.

[gavinc69]

Didn't notice any difference with the 044 on, and after reading an old post from 'Dr J' looks like the cause of the issue is the Bosch 0 438 100 031 fuel distributor.

Options :
1. Install a 0 438 100 097 FD, they flow more but not sure if its enough. Been trying to find one to buy and they are no where to be found.

2. Have my FD rebuilt and modded to flow more. Still no guarantee it can be made to flow enough, so after a £500 rebuild I still may be going lean up top.

3. Go EFI. Although more work to do it basically gets rid of all the current K-Jet restrictions I'm having now and any possible future issues. Plus I can build on it.

[gavinc69]

List of parts to go EFI (Let me know if I'm missing anything) :

3.2 Carrera intake (I can get a complete one with no injector's)
3.2 Carrera injectors (24lb) or maybe go a little larger!)
Carrera 42mm intake to SC manifold adaptor set (from TurboKraft)
Microsquirt ECU & harness
3bar MAP sensor
Engine temp sensor
Air Temp sensor
Fuel line
Fuel line T piece's etc
Rising rate fuel pressure regulator
O2 exhaust sensor

Plus various clamps, clips and sundry parts...