75 Performance.

Started by Duk, May 27, 2011, 08:09:52 PM

Previous topic - Next topic

festy

Quote from: Darryl on May 01, 2012, 07:53:02 AM
Quote from: Duk on April 30, 2012, 09:54:23 PM
Strangely, the computer was switching on with 12 volts fed into the auxiliary output  ???

Hopefully/possibly it was being powered via a protection diode from aux out to +ve rail (to prevent aux going above 12v, assuming 12v is actually connected).
+1 - I'd guess the output is something like an open collector driver with a back-emf diode (so the output can safely drive relays) - and that diode was feeding the power into the ECU because the "output" pin's voltage was higher than the (unconnected) power rail.
If that's the case, then there shouldn't be any damage done.

How confident are you that the 1.6mm exhaust pipe brace will be rigid/strong enough?

Duk

#61
Quote from: festy on May 01, 2012, 09:54:11 AM
Quote from: Darryl on May 01, 2012, 07:53:02 AM
Quote from: Duk on April 30, 2012, 09:54:23 PM
Strangely, the computer was switching on with 12 volts fed into the auxiliary output  ???

Hopefully/possibly it was being powered via a protection diode from aux out to +ve rail (to prevent aux going above 12v, assuming 12v is actually connected).
+1 - I'd guess the output is something like an open collector driver with a back-emf diode (so the output can safely drive relays) - and that diode was feeding the power into the ECU because the "output" pin's voltage was higher than the (unconnected) power rail.
If that's the case, then there shouldn't be any damage done.

Unfortunately they are switch to ground drivers.
I also posted my dilemma's on the Adaptronic forum and Andy, the head engineer from Adaptronic (a top bloke who is an absolute petrol head) replied this morning and said that it would have killed the output drive.
Oh well, I should be more observant.

Quote from: festy on May 01, 2012, 09:54:11 AMHow confident are you that the 1.6mm exhaust pipe brace will be rigid/strong enough?

Very!  8)
Remember that the brace is there to augment the chassis strength, rather than be the chassis.
Also, it's the diameter of the pipe that is the great giver of strength. Ideally there would be a straight piece of pipe from the driver's side damper/top control arm box section directly over to the passenger side A pillar and the same set up on the other side, but some clown put this big boofy engine in the way  :P

Duk

#62
I finally got my big aluminium eBay radiator today.
It's originally for the VL onwards V8 Dunnydores and is quite huge compared to the original.
I had ordered 1 for a manual car because they don't have the built in trans cooler, but guess which 1 they sent. Given the issues with the freight company I had, I'll work with what I've got. The reason I wanted the manual radiator was so I could remove the lower outlet, blank the hole and cut another 1 further up and reweld the nipple onto the tank. But the lower outlet lines up well with the hole in the radiator support panel, so I'll just enlarge that hole and make a stainless adapter pipe. It'll be obvious when I get it done.
I will need to cut new lower locating holes in the radiator support panel and figure out a way to hold the top of the radiator to the body.
A simple blank cap will be used instead the cheap radiator cap that came with it. It will allow the coolant to be filled much more quickly, too.
The hose to the header tank will be pretty frigging long 'cause it's on the other side of the radiator.

I thought I might try and use the auto trans heat exchanger for cooling the power steering fluid. The fittings are pretty small though, so it would have to be pumped into the radiator straight from the pump rather than be in the return line for the reservoir.
I then thought that the heat exchanger wouldn't be designed with that sort of pressure in mind and chucked that idea in the bin  :P.

For the cooling fan, I'll cut the mounting arms off of the fan's frame and realign them to the top and bottom steel flanges that bolt to the radiator.

Anyway, I certainly expect there to be plenty of cooling capacity with this set up. I want to upgrade the air conditioner's condenser too, and I'll probably have to move the A/C dryer to in front of the radiator with the condenser. Getting it all to fit behind the grill and bumper bar could be interesting.

***I also finally got my new water pump from OKP today too. That took 4 weeks despite some pretty pricey freight. It seems to me that Potenziata water pumps are the proverbial rocking horse poo, because despite it being said to be a Potenziata pump on their website and on the packaging, it aint.............  ::)***

Darryl

Quote from: Duk on May 01, 2012, 11:12:51 AM
Quote from: festy on May 01, 2012, 09:54:11 AM
Quote from: Darryl on May 01, 2012, 07:53:02 AM
Quote from: Duk on April 30, 2012, 09:54:23 PM
Strangely, the computer was switching on with 12 volts fed into the auxiliary output  ???

Hopefully/possibly it was being powered via a protection diode from aux out to +ve rail (to prevent aux going above 12v, assuming 12v is actually connected).
+1 - I'd guess the output is something like an open collector driver with a back-emf diode (so the output can safely drive relays) - and that diode was feeding the power into the ECU because the "output" pin's voltage was higher than the (unconnected) power rail.
If that's the case, then there shouldn't be any damage done.

Unfortunately they are switch to ground drivers.
I also posted my dilemma's on the Adaptronic forum and Andy, the head engineer from Adaptronic (a top bloke who is an absolute petrol head) replied this morning and said that it would have killed the output drive.
Oh well, I should be more observant.

Bugger - obviously he would know. Slightly strange/unlucky though (but I don't know the cct) - I expected it to be a switch to ground output - if it was and it had a protection/back-emf diode to 12v that would have been fine so long as the output didn't turn on... Maybe it did turn on...

Duk

Would a back EMF diode protect it though?
I think some form of current limiting would have protected it, but because the current flow is from the load, through the wire, through the transistor and then to earth, I don't think that a back EMF diode would have helped. Basically current flow was in the normal direction but because there was basically no resistance between the battery and the transistor, it would have easily been over loaded. Max resistive load is 7 amps (max inductive load is 3 amps).

Oh well, I can still do plenty of work with it. Andy said to send it back the Adaptronic for repairs and checks.

festy

If the output isn't turned on, the transistor doesn't conduct so the current goes straight to the 12v rail via the diode.
If the transistor was conducting, then the current would go through the transistor to ground - but I'd assume there'd be some form of current limiting resistor to protect the transistor in normal use.

But if their engineer reckons it'd be toast, it must be some other kind of circuit...

Duk

#66
Good point Festy! I'll do a bench test and set it up to do something different before I send it back to Adaptronic.

Anyway, some photos showing the nearly complete (but not quite) main loom and the sub looms for the ignition system and the injectors.
I've incorporated the power supply for the ignition system, water injector and the fuel injectors into the main loom and also allowed for current limiting resistors to be plugged into the loom. For the standard injectors the resisters won't be needed and the 2 plugs can be joined together, but because I plan to use Skyline GTR injectors that will be wired in parallel, it will be possible to reach the current limit of the injector drivers.

I still have to wire in the digital inputs for the computer as well as get a speedo sensor signal into the computer. Plus I need to make a small forth loom that the main loom will also plug into for the fuel pump and cooling fan relays. The forth loom will also have the inputs for the brake fluid reservoir level, the coolant temperature sensor for the gauge and I want to add a relay for the starter motor while I'm at it.

All in all, to do a reasonable backyard installation of a programmable computer, it's a fair amount of time consuming work if you want the whole thing to be reliable, reasonably well presented and well integrated into the rest of the car.

shiny_car

They look beautiful and neat. I'm a big fan of quality wiring jobs that incorporate form and function.

:)
Giulietta QV TCT . 1.75 TBi . Magnesio Grey - Black
GT . 3.2 V6 . Q2 . Kyalami Black - Red
75 . 3.0 V6 . Alfa Red - Grey

Duk

Cheers Shiny!

The main idea is for them to be reliable for a very long time. The idea of being strandard because I couldn't be bothered to do a decent job or used cheap bits and pieces, is a crap one. 1 nice thing about the V6 is that no wires need to go near the exhaust manifolds, so there is no chance of cooking anything.
It's amazing how long it has taken me  :o. I hate wiring at the best of times (Fitter and Machinist by trade), but I've allowed this 1 to drag out too long  ::).
It'd be nice to be able to easily take apart the 2 black plugs so I can remove unused wire from them. There will be 4 or 5 wires connected inside the car and after those are done, the other wires are surplus and I hate the idea of just chopping them off near the plug.

scott.venables

How well does the engine loom separate from the rest of the car?  ie. How simple was it to make your engine loom without disturbing the chassis wiring?

I didn't quite follow your plan with the radiator, is it going in front of the radiator support panel instead of behind it?

Do you plan to finish your extractors?  Are they 1.5"OD or 1.625"?

Scott

edit: just remembered you've got a Potenziata, the wiring might be different?

Duk

#70
Hey Scott,

To get the car to run, the wiring loom joins the car in 5 places. Later I'll add the digital inputs for things like the A/C on signal and speedo signal. These are there to help the Adaptronic deal with idle speed control.

1: The original ignition coil's switched power. This switches power on to run the computer and switches on the 2 relays for the fuel injectors and ignition coils. Relays and fuses are mounted on the same mount that holds the Adaptronic in place under the dash.

2: The Adaptronic's tacho output (an auxiliary output that switches a relay coil on and off to give the required electromagnetic signal that simulates the old ignition coil, for the Alfa's older style tacho) to the original tacho feed that originally attached to the ignition coil's negative terminal.

3: A high current power feed for the injectors, ignition coils and water injection solenoid valve is integrated into the main loom and connects to the power distribution point near the battery.

4: Sent from the main loom to the (yet to be completed) 4th loom, the signal to switch on the fuel pump's relay.

5: And also sent from the main loom to the (yet to be completed) 4th loom, the signal to switch on the radiator fan's relay.

There is also the ignition module which plugs into the main loom on 1 side and the ignition coil loom on the other side. And the current limiting resistor pack that has 3 50 watt resistors for the injectors and 1 for the water injection solenoid valve.

I cut the body loom for the original ignition coils power and the tacho signal wire and used a 2 pin plug there.
The worst part will be the 4th loom. I'll cut off the black 9 pin (only 6 pins actually in it) plug near the driver's side A pillar so I can use a new plug that I have the pins for.

I will finish the passenger side extractors 1 day. I stopped because I needed to focus on getting the car working again. I plan to get my hands on another engine and that will make it a lot easier to complete.
Pipe size is 1.5" 500mm long give or take about 25mm.

The radiator will sit in the car the same as standard. The radiator's support panel has 2 angle sheet metal attachments that have large diameter holes in them. The bottom radiator outlet will go though the passenger side sheet metal attachment with the hole and is about level with the anti-roll bar. I have to enlarge the hole and cut new holes in the radiator support panel.
My car had been in a bingle at some time in its life and the radiator support framework is distorted a bit, so I'm not overly fussed about drilling holes in it.

Duk

#71
Well I put a lot of the engine back together today with great aspirations of trying to start the thing. I checked the ignition coils worked. Temporarily wired the fuel pump to a switch and hit the starter.
Click! Hmmmm Click, click.
Tightened a few terminals and added another earth lead.
Click!
This was strange, I had wound the engine over on the starter to try and check the CAS signal, but now nothing.
Eventually I found that the main lead to the starter motor wasn't tightened.
With that done it would crank  ;D.
Unfortunately no joy  ???.

Either the crank angle sensor is dead (and Steve (four90s) said it was an unknown), I haven't plugged it in properly or I've wired it back to front. When I originally cranked the engine to check the CAS I also put my multimeter on it just to measure frequency and was getting a reading, so maybe I haven't plugged it in properly.
It's a bloody big shame that all of the assembly work I did today has to be undone to get to the plug  :-[.

MD

Hey Dukster,

If I get your story right. You cannot even crank the motor? If so, go back to basics.
Forget the entire running circuitry. Just follow up the starting components.

Is the battery flat?
Does your solenoid have B+ when you hit the start sequence?
Is the solenoid working or is it stuck or gone open circuit?
Does the starter have B+ supply?
Does the starter actually work for sure?

If all these basics are sound, then there is absolutely no question that the engine should turn over. Whether it fires is a whole other can of worms...
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0

Duk

Quote from: MD on May 05, 2012, 07:56:52 AM
Hey Dukster,

If I get your story right. You cannot even crank the motor? If so, go back to basics.
Forget the entire running circuitry. Just follow up the starting components.

Is the battery flat?
Does your solenoid have B+ when you hit the start sequence?
Is the solenoid working or is it stuck or gone open circuit?
Does the starter have B+ supply?
Does the starter actually work for sure?

If all these basics are sound, then there is absolutely no question that the engine should turn over. Whether it fires is a whole other can of worms...

Mister Dee,

it seems that my communication skills need to be upgraded. I did indeed get the engine to crank
Quote from: Duk on May 04, 2012, 06:18:32 PM
Eventually I found that the main lead to the starter motor wasn't tightened.
With that done it would crank  ;D.
but the engine would not fire because the crank angle sensor isn't providing a signal. Or atleast not 1 the computer understands.

MD

No,your comms seem good. It's my reading skills need ficker lenses. Sorry about that. :-[

Next basic question, have you done anything to change the timing?

I had a hell of a time getting the timing right for the Cab . I finally found where the crappy timing mark is on the pulley. (see photos)
Also had to get a new crank angle sensor as the original unit had about as much hope of delivering a signal as Caesar's dick.  ;D

The timing marks on the V6 may be different but the nature of the mark will be the same I feel sure.
Transaxle Alfas Haul More Arse.

Current Fleet
Alfetta GTV6 3.0
Alfetta GTV Twin Spark supercharged racer
75 1.8L supercharged racer

Past Fleet
Alfa GT 3.2V6
Alfetta GTV 2.0
Giulia Super 2.0
Berlina 2.0