EFI for Doris

[RussellT]

I have started a new thread for updates on this project.
Story to date
With the new head from Prima racing bigger turbo and new standard compression pistons Doris produced 230 bhp at 19psi. The turbo is good for more pressure but the engine was emptying the carb faster than the fuel system could fill it and she started to lean out.

I have purchased twin motorbike throttle bodies from a Yamaha E6 600 my pit crew has made a inlet manifold with 2 inlet ports served by each throttle body.
The pit crew has also made a swirl pot to go around the fuel sender which required me to cut out a baffle in the fuel tank.
I have designed and the pit crew are fabricating a plenum chamber from aluminium, and finally I have just ordered a pair of Black Ops 1000 cc EAT 287 compatible injectors from fiveomotorsports in California.

https://www.fiveomotorsport.com/suzu...-eat287-eat286

Still on the job list; pressure test the new manifold, sort out a fuel rail, pressure regulator and high pressure pump. A level indicator in the reserve tank. The throttle cable.

Paint.

Things are getting exciting.

https://www.rtoc.org/files/Technical%...20complete.jpg

[Matt Cole]

Russell,

Can't wait to see the finished job especially and hp increases from the efi and tb's. Hopefully you will do a power run at the same boost to see the difference.

I will be blunt, but I'm not convinced with that manifold? it's certainly not the prettiest thing I've ever seen. I guess the proof will be in the pudding and I'll get my spoon ready!

[RussellT]

You could well be right Matt. It should flow and mix I just hope each cylinder is equally served, there is a potential for the outer ones to run lean. I can try a infra red thermometer on the exhaust manifold or a cooking thermometer might show up a issue. We have to get it to run first!

R

[Ian S]

Hi Russell, I don't want to sound overly negative or excessively critical, and it's sometimes somewhat interesting when people do an EFI conversion to their carb'd five. And perhaps that photo is not representative of what is going on there, but from that it looks like it shouldn't flow! There can be a fair bit of engineering to this task to optimise it, and from that it looks like none has been applied?

There have been / should be so many photos of EFI conversions around to have a look at. A few with 5GTT C1J's. philr5t 's one made maybe 330BHP from a single throttle body and a smoother looking manifold with no 90° bend in the middle.

That welding (brazing) on yours is terrible looking. Maybe it will grind off but should not be like that in the first place.

Have the people you're using ever done welding before? Or made and inlet manifold?

A few photos here: https://www.rtoc.org/boards/member.ph...ichael-tierney
philr5t photos seems to have disappeared.
Andrew Cooke photos seems to have disappeared.

[RussellT]

Cheers Ian
You need a bit of swirl! besides nothing set in stone we can always have another go. It may leak like a sieve when we pressure test it. Your comments will go down well with the pit crew (especially Andy's co workers!)

Anyway a more pressing issue has arisen. Due to a misconception of how the reserve tank fed the main tank, with my swirl pot in place she ran out of fuel (with Andy driving and he had no phone so left to walk back to the garage). Heads been scratched and back to the drawing board.

Russell
https://www.rtoc.org/files/Technical%...wirl%20pot.jpg

[Ian S]

http://inoxlineperformance.pagespers...oinjection.htm similar to Phils that was made by Big Jim Racing.
http://www.protoxide.eu/en/intake-ma...injection.html
http://www.turbosport.co.uk/showthread.php?t=176634
http://www.forum-auto.com/automobile...83958-1225.htm Scroll down a few posts.
http://www.mikadoracing.com/index.ph...nnonce=1763569
http://megbytes.free.fr/GTT/Titine/M...2/P1010738.JPG from http://megbytes.free.fr/GTT/Titine/M...2/P1010738.JPG

[Matty]

For an optimised setup you really need 4 ITBs joined together with a plenum or a plenum with a single TB on the end.

On an inlet manifold with a small volume you run the risk of unequal charge getting to each cylinder, as the the pressure in the inlet doesn't stay consistent.

What you have there, is effectively 2 inlet manifolds which are now of a Siamese port design. This isn't too much of an issue on a carb as you have a wet manifold setup, but on an EFI setup you can have serious issues with charge robbing between cylinders.

If you plan to run that inlet manifold, you really need to test it with an equal length exhaust manifold with a EGT sensor boss on sample tubes on both inner and outer cylinders to check the difference.

[RussellT]

I have the same concerns Matty hence the comment about using an infrared thermometer. I wonder if you can get temperature sensitive paint. In medicine we use a tape that changes colour at a certain temperature to show that instruments have been correctly sterilised. I could put that on the exhaust runners. Thermocouples would be another idea.
I reckon that the induction strokes on the 2 pairs of cylinders follow each other so as long as the turbo can supply the air flow the second induction stroke should obtain the same air fuel as the second assuming the path into the cylinder is not unfavourable. We have connected the 2 sides so as to help equalise the pressures. Anyway as I keep saying we have to get her to run first.

The injectors arrived today
https://www.rtoc.org/files/Technical%.../injectors.jpg
https://www.rtoc.org/files/Technical%...20details.jpeg

[Ian S]

If I'm not confused, adjacent cylinders, will be sucking at the same time. One nearing the top of it's exhaust stoke and the scavenging sucking some initial air in during the overlap. And the adjacent one nearing the bottom of it's induction stroke, hence the robbing of air.

Or maybe that's one and three, etc. I can't think it through clearly just now.

Is it not that air is elastic and columns of it squeeze up behind a closed valve and burst through as the valve opens. A pulsing effect.

[RussellT]

Pressure testing the inlet manifold with an air line to 40psi. All ok.

https://www.rtoc.org/files/Technical%...ure%20test.jpg

[Matty]

An infrared sensor will work if you can get one that goes high enough, mine goes to 300 degree C then won't read.

Exhaust temps will be around 600-800degrees I would think.

Ian with the firing order being 1342 or if you look at it 3421 3 and 4 and 2 and 1 is where you get the issues. When 2 opens the air is effectively static on that runner, so you get a momentary pause on air going into that cylinderswhilst fuel is being squirted in, so when 4 opens air is already flowing through that port (TB in this case) so you can end up with a leaner mixture on the second pot to take the air.

Depening on the runner efficiencies and lengths they can run more efficiently at different rpms. So you may get rich inners at low RPMs and leaners outers the opposite at higher rpm. With a single lambda reading taking the average, it doesn't give a true reading of what is going on with each cylinder. Tuning slightly on the rich side is a compromise to stop det but may sacrifice some power.

[RussellT]

The new injectors fit with no need to modify the throttle body or the fuel rail, which is good.
I have renewed my insurance with HIC all modifications notified and EFI added but annual milage reduced from 10K to 5K with 1K on business use and my premium went from £402.30 to £275.00.
I have also renewed my motorsport licence £60.

By the way my speed event colleagues have been talking about Javelin speed events. They are run outside of the MSA and their motorsport licence is just £5 per event. The events are £139 but do include some classic circuits like Croft. Might be worth a look.

[RussellT]

The finished inlet manifold

https://youtu.be/xlwBPscK5Nk

[RussellT]

First trial fitting of the new inlet manifold with the TB's on Doris
https://www.rtoc.org/files/Technical%...20TB's.jpg

[RussellT]

Plenum back from the welders
https://www.rtoc.org/files/Technical%...num%20done.jpg

Note my plenum is before the throttle butterflies not after it/them. Is that significant?

[Matt Cole]

Looking all very good Russel. when are you planning for mapping?

[RussellT]

Plenum trial mounted. Throttle cable sorted. Next task is to relocate the coil pack, it just needs to n=be moved to the nearside a tad.

I will be contacting Scoff at EFI for info on the wiring of the air and water temp sensors and a base map to try and get her started.

https://www.rtoc.org/files/Technical%...%20mounted.jpg

[Matty]

That looks good. Plenty of volume which is always good.

[RussellT]

We have hit a bit of a snag with my design.

Due to the siamesed ports and twin injectors with the 1342 firing pattern the injectors have unequal gaps between firing. If we batch fire (both injectors fire each TDC) the inner cylinders will get a lot more fuel than the outer ones.

Scoff has a cunning plan. Fingers crossed it works.

[Matty]

The way the mini boys get around it, is to run two different Fueling maps for the inner and outer cylinders, it takes a bit of setting up, but plenty running good numbers now. You'll have to run an additional cam sensor to get the timing in phase with the camshaft, rather than just the crank position.

Personally I would avoid batch fire, as that always seems a bit of a compromise, especially after all the effort that has gone into fitting the efi.

Could you get away with running it semi sequential and pairing the injecting together so the firing is more even?

[Matt Cole]

[RussellT]

Could you get away with running it semi sequential and pairing the injecting together so the firing is more even?

Great minds think alike.. that is the cunning plan.

[RussellT]

Utilising the dizzy as a cam position sensor.

The rivet on the arm is drilled out and the copper contact replaced with a small bolt. Its adjustable by turning the distributer on its shaft.

https://www.rtoc.org/files/Technical%...%20trigger.jpg

Start up is planned for Sunday The latest issue we have is that I couldn't get the ECU to talk to my laptop. In 2 days that has to work.

R

[Matty]

If you are running a comms port to USB adapter, some just don't work with ECUs, may be worth trying another one if that is the case.

[RussellT]

It has worked previously always been a bit temperamental but by chance I have another serial port addapter I can try

[Matt Cole]

If its them cheap Chinese ones forget them ever working correctly! I need a good quality one for my 420b. I just cant get it to work on a modern USB laptop!

[RussellT]

My mistake. In the dark, wed night fiddling in the glove box I connected the 6 and 8 pin plugs the wrong way around. Connects to laptop now I just hope I havnt goosed the ECU.

[Trevhib]

[RussellT]

She runs! Scoff got her running and I've driven to his unit and she is on the rollers as I type Quite a lot of pops and bangs at the moment

[Matt Cole]

Any more news Russel? Dying to know the figures!

[RussellT]

Any more news Russel? Dying to know the figures!

Scoff spent today just getting her to work. Predictably some issues with the unusual set up. Fuel can pool in the inlet on idle causing coughs and splutters when you open the throttle. Also issues with enrichment on throttle opening. The first cylinder of the pair scoffs the lot leavin the second cylinder rich.

However she runs sweet throttle response a tad inconsistent but far from bad.

Anyway at 14 psi she produces 180 BHP and 171 lb/ft torque.

[Matty]

That's good numbers for the boost. have you got it to a point of being a nice drive?

Siamese inlet ports really don't lend themselves to EFI setups unfortunately.

Injector angles can play a big part also, but you will always get more power with individual inlet runners.

[RussellT]

Scoff has worked his magic and she isn't half bad. I've booked to go back for a final shake down and to what she can do at race boost. If she can't beat 231 the soles is back (maybe)

[Trevhib]

If you can't beat the peak power figure it might not be the end of the world. You might get power curve or spool benefits that result in a quicker car (and perhaps be more reliable in terms of fuelling through the range)?

[RussellT]

One big plus with the EFI this morning. 4 deg in the garage and instead of the endless cranking and pumping of the accelerator pump to get her going draining the poor battery in the process. Turn the key and bang she starts and doesn't stop at junctions. Its just like a modern car.

[Trevhib]

[michael tierney]

If you can't beat the peak power figure it might not be the end of the world. You might get power curve or spool benefits that result in a quicker car (and perhaps be more reliable in terms of fuelling through the range)?

when i was running twin carbs with 2 manifolds the torque was higher and it came in quicker.......so you might have that to look forward to!!

[RussellT]

A link to a short vid of Scoff starting to work his magic. I set him quite a challenge to get this odd system to work. This is very early days and she doesn't pop and bang like this now.

https://youtu.be/9Ct46Ds_iAI

[RussellT]

when i was running twin carbs with 2 manifolds the torque was higher and it came in quicker.......so you might have that to look forward to!!

To be an effective sprint and hill climb car it's mid range torque that you want.

[michael tierney]

any figures yet??

[RussellT]

ill post a low boost graph, that's all I have at the moment Scoff spent all day making her work.

[RussellT]

As promised

[michael tierney]

too small Russell

[RussellT]

You've been talking to my wife!

I'll have another go

[RussellT]

[Trevhib]

That's better

That's nice power and torque at that boost. I think with the right set-up (and increased boost), there'll no going back to carb.

Where is that boost reading taken from? Turbo, manifold or somewhere in the middle?

[RussellT]

That's from the manifold

[Matt Cole]

So when will we see full boost results Russel?

[RussellT]

Ive booked to go back on the 19th Feb

[Matt Cole]

Ive booked to go back on the 19th Feb

I've put it in me calender!