Future Classics and Design Icons

[Rottbott]

That was based on doing 80-90 on the motorway but doing 70 never seemed to make much difference anyway.

The turbo engine does 30 mpg at 80-90, it's a very welcome improvement over the old one. It will probably do even better now, I've improved the fuelling map a lot since my last motorway trip.

However... it does provide the (irresistable) opportunity to drive it so fast that it will chew through a tank of fuel in no time on the twisty roads! I get roughly 15 mpg on the way to work and back if I go fast.

[NickT]

Rottbott Wrote:That was based on doing 80-90 on the motorway but doing 70 never seemed to make much difference anyway.

The turbo engine does 30 mpg at 80-90, it's a very welcome improvement over the old one. It will probably do even better now, I've improved the fuelling map a lot since my last motorway trip.

However... it does provide the (irresistable) opportunity to drive it so fast that it will chew through a tank of fuel in no time on the twisty roads! I get roughly 15 mpg on the way to work and back if I go fast.

I can imagine you programming it on your laptop on your knee as you are driving along

Are you using an 'Adaptronic' ecu ? I thought these were supposed to be quite good at self learning. I've not used them though.

NickT

[Flux Capacitor]

What if I am driving at around 10-30 MPH in London?

[Guinney1971]

Flux Capacitor Wrote:What if I am driving at around 10-30 MPH in London?

I didnt realise you could get up to double figure speeds in London these days... :lol:

[Rottbott]

NickT Wrote:I can imagine you programming it on your laptop on your knee as you are driving along :)

Are you using an 'Adaptronic' ecu ? I thought these were supposed to be quite good at self learning. I've not used them though.

NickT

Haha, I usually try to get a passenger who can work the laptop when I'm fiddling it. And yes, I'm using an Adaptronic.

There's tons of things you can fiddle with but mostly I just drive it around in its 'slow converge' mode which (if you have a wideband lambda sensor plugged in) adjusts the fuelling to match the table of target AFRs you give it.

I'm still not sure it's quite right, but my current target AFR table looks something like this:

0-40 kpa: 14.7
40-80 kpa: 14.7
80-120 kpa: 13.0
120-160 kpa: 12.5
160-200 kpa: 12.0

I don't vary it based on rpm but maybe I should. I have no idea what sort of intake pressures normal non-turbo PRVs see.

[BELFAST BOY #1458]

:o I Think I am getting about 20mpg, but cant fugure out why? :twisted:
I cannot use my D on a daily basis 'cause it would cripple me on fuel costs, I bought her to look good in my garage and hopefully gather money.
My D will be passed on to the my kids when I peg it

just looking out the window here in work and relized that another reason I would not use 1458 all the time ,is lunatics that like to have road rage , just like the van and vw polo are outside my window right now!!!

[NickT]

Rottbott Wrote:

NickT Wrote:I can imagine you programming it on your laptop on your knee as you are driving along

Are you using an 'Adaptronic' ecu ? I thought these were supposed to be quite good at self learning. I've not used them though.

NickT

Haha, I usually try to get a passenger who can work the laptop when I'm fiddling it. And yes, I'm using an Adaptronic.

There's tons of things you can fiddle with but mostly I just drive it around in its 'slow converge' mode which (if you have a wideband lambda sensor plugged in) adjusts the fuelling to match the table of target AFRs you give it.

I'm still not sure it's quite right, but my current target AFR table looks something like this:

0-40 kpa: 14.7
40-80 kpa: 14.7
80-120 kpa: 13.0
120-160 kpa: 12.5
160-200 kpa: 12.0

I don't vary it based on rpm but maybe I should. I have no idea what sort of intake pressures normal non-turbo PRVs see.

Looks like use use a Map sensor to sense turbo pressure at the inlet manifold and increase fuelling to suit. I hope you are using an ignition retard too for safety. For 95 ron it is approx 1 to 1.5 degree retard per psi boost. A knock sensor, even if it is for an alarm or so may be useful.

I bet that "More Power" button on the laptop will be worn out by the time you have finished you turbo monster

Try and get a fixed map sorted as feedback from a wideband can be relatively slow as a control feedback function. I would use the lambda as a fuel trim on a self learn.

Good luck with the project. I'd love you to take me for a spin in it or let me see your stonking rolling road results.

NickT

[Rottbott]

NickT Wrote:Looks like use use a Map sensor to sense turbo pressure at the inlet manifold and increase fuelling to suit. I hope you are using an ignition retard too for safety. For 95 ron it is approx 1 to 1.5 degree retard per psi boost. A knock sensor, even if it is for an alarm or so may be useful.

I bet that "More Power" button on the laptop will be worn out by the time you have finished you turbo monster :D

Try and get a fixed map sorted as feedback from a wideband can be relatively slow as a control feedback function. I would use the lambda as a fuel trim on a self learn.

Good luck with the project. I'd love you to take me for a spin in it or let me see your stonking rolling road results.

NickT

Yes, it's based off a 2 bar MAP sensor. Both fuel and ignition are run off a big lookup table of load vs. rpm. There are open and closed loop modes so fuel can be optionally trimmed by lambda sensor. I'm currently on a conservative ignition map with quite a lot of retardation at high boost to be sure it doesn't knock. I also have two knock sensors - the built in one which the ECU watches in case of emergency, and another I've borrowed for tuning, which is more sensitive and gives me an LED readout on the dashboard.

The learning modes work well but do require you to stay in cells on the map for a certain period of time, which can be tricky while driving. The proper way to do it is on a dyno so you can hold it in place and reach all parts of the map, which I can't afford yet.

Here's an example of how the maps look:

An older fuel map:


Ignition - this isn't mine, it's off a Nissan turbo engine but it's similar:



Hopefully I can bring it along to a show in the summer if there are any big ones left. If not it'll be Eurotec next year I guess.

[NickT]

Looks interesting Rob. You are going the right way being conservative then working up.

Have you tried using a lower boost and more ignition advance?
Obviously more boost you apply the higher the intake charge.
Have you got an air intake temp sensor to monitor this or maybe one before and one after a charge cooler to see how much the temp is reduced?
All good stuff. You should be known as "Turbo-Nutter Rob"

Take some videos or pics when you do put it on the rollers.
I bet you can't wait. (Go on, stick it on a credit card. Go on, go on go go on go on......................)

NickT

[Rottbott]

I'm still trying to get the full amount of boost I want. I'm aiming for 1 bar but my wastegate/controller won't go up that far -- probably wants a restrictor putting in between the intake and controller.

I have an air temperature sensor after the chargecooler which I haven't got around to calibrating yet. When I do I can have it trim the ignition at high temperatures as well as dumping in more fuel when starting on cold days.

Putting another one in before the chargecooler is an excellent idea, I'd be interested to see exactly how efficient it actually is.

I need to buy myself new window motors before doing any more performance stuff though, otherwise I'll boil to death in there!

I definitely did not reach 140mph in it the other day before coming up behind other traffic, but if I had I expect it would still have been pulling nicely. Martin's guess of 150-160mph top speed (based on what a turbo GTA does) seems pretty accurate.

[NickT]

Get it on the rollers instead of guesses

I'm looking into rolling roads around here just for a power run on mine and Bozzzys as a bench mark of a stock engine with cat bypass & a stock engine with full stainless performance exhaust system with fuelling adjusted.

Fingers crossed this will happen sooner.

NickT.

[Rottbott]

I know, I know. Will do it when I have the money, promise!

[NickT]

Rottbott Wrote:I know, I know. Will do it when I have the money, promise!

OK no worries

NickT

[stunned_monkey]

Rob's running my Innovate LM-1 lambda which is super fast and natively supported by the adaptronic via its serial port. It has been mapped across the boost range and the ignition has been pushed as far as possible within sensible limits on the road with no knocking under any conditions we could create (we tried). Once in the right range, improvements gained by ignition advance tend to be small, with less than 5% increase in power over a fairly wide adjustment window. The Z7U engine is known to produce its maximum power at or slightly over a bar of boost, but beyond you just get more noise until you start playing with higher lift cams. The PWR barrel chargecooler has been shown to be considerably more efficient than the standard intercooler in a GTA turbo, although they run theirs daisy-chained. A stock 200hp GTA Turbo has a top speed quoted of 155mph. It has slightly higher gearing in 4th and 5th but smaller wheels. It's also much more aerodynamic than a DeLorean. A tweaked GTA will push 260hp at a bar of boost, and has its rev limit at 6000rpm. Rob's is set at 6500 which is where Venturi put it in the 2.8's and Renault did in the 3 litres. At 5500rpm at a bar, the engine is consuming around a litre of fuel a minute, based on Rob's map, injectors, fuel pressure etc. That's around 140mph.

Edit: It's just occurred to me that that's roughly 2p per second in fuel!

[Guinney1971]

I'm sorry - and I know I've had my own moments of daftness with the loud
pedal in my car in the past - but this just sounds insane to me.

If I wanted to drive stupidly and illegally fast, I certainly wouldnt do it in
a car that was nearly 30 years old - I'd take one of my bosses Merc's out
for a thrash instead :wink:

I've just had a rather frightening MOT on my Cav, which is only 15 years
old - luckilly we've got it sorted and the car is safe to drive again, but I'm
now certainly more wary about the way I handle older cars.

Not wishing to piddle on the pyrotechnics here, and I'm sure Rob is very
pleased with the work done, so please dont get me wrong, its just my 2pth