ITB EFI DIY guide

[Redracn]

So today I redid the wiring and now have two of the sr igniters wired in (I had a spare already, so was the easiest option). So one channel per coil now. We spoke to Link about driving two igniters per channel and they seem to think it will be ok.

The double rpm thing I knew about from the beginning, the car is primarily going to be used on the road and if it see the track more than once a year I'd be surprised. So it shouldnt be to big a problem for my use.

Thanks for your input Redracn, hopefully end up with a better overall result.

Glad to have helped. I would chase Link for approval in writing as this is something they should know and if not capable you could damage the ignitors. One of the reasons I sold my shares in a major aftermarket ECU manufacture I co founded was that the front line field and support staff were not up to scratch when it came to technical engineering issues and stopping them from giving out bad/incorrect information became too big a task. You would be surprised at how little the support staff actually know in even the better ECU companies. 

[Peter M]

On ‎27‎/‎10‎/‎2017 at 8:04 PM, Redracn said:

Glad to have helped. One of the reasons I sold my shares in a major aftermarket ECU manufacture I co founded was that the front line field and support staff were not up to scratch when it came to technical engineering issues....

Redracn,

What's you views about the value of running knock sensors on the pre 964 engines? 

I note Clewett's produce a triple mount that bolts to the underside of the heads, most mid price aftermarket ECU's have two channel knock sensor capabilities and the sensors themselves are inexpensive.

Do you think it is worth the expense and set up costs to be able to run a few more degrees of advance on a street engine?

Thanks

Peter

[Redracn]

On 25/11/2017 at 1:58 PM, Peter M said:

Redracn,

What's you views about the value of running knock sensors on the pre 964 engines? 

I note Clewett's produce a triple mount that bolts to the underside of the heads, most mid price aftermarket ECU's have two channel knock sensor capabilities and the sensors themselves are inexpensive.

Do you think it is worth the expense and set up costs to be able to run a few more degrees of advance on a street engine?

Thanks

Peter

Knock is one of those things that has infinite shades of grey. Pretty much any method can detect the block being hit by a sledge hammer but that is of little use if your engine has been destroyed at a much lower knock level. So what matters most is the Signal to Noise ratio. If it is not good enough you will not detect potentially destructive knock. There are many sensing methods and of those commonly used the bolt on the side sensor provides one of the worst SN Ratios and is very location dependent. Direct cylinder pressure measurement being at the other end and mega $$.  There are also many signal processing methods from a simple band pass filter to windowing and multi frequency DFT analysis. One of the most time consuming and potentially expensive jobs is proving that the knock system on any given engine actually works and can detect low levels of knock over a wide range of conditions. To do this the engine must be made to knock and you need a more accurate referance such as cylinder pressure to quantify the system. Often a simple signal processor and expert human ear stand in for the mega $$ stuff. 

Little things matter even brackets as they can resonate a specfic frequencies giving false positives and masking any real signal. Setting up/verifing the knock system has to be done in the final installation in the car. Just having a different alternator bracket from the car it was setup on can make or break the installation. This also means gearboxes, mounts etc. nothing on the engine/gearbox should resonate at the frequencies of interest and this includes the cooling fins in an air cooled engine. 

Rear engines also suffer from rocks hitting the transmission/engine causing false positives. So covers /sheids are required. False positives make race cars go slower. 

I an not aware of any AC Porsches with a aftermarket known properly functional verfied knock control system using bolt on sensors but they could exist. Even the 964 is pretty ordinary compared to todays efforts as were most cars from that era. Again any system can claim it will detect knock and that would be true but can it detect low enough levels of knock and correct it before it becomes destructive. 

Not all engines are knock limited. On some the tourque stops increasing as you advance the ignition with no sign of knock. I have seen engines go 10-15 degree past where the torque stoped increasing with no knock. On an engine like this knock control would be a waste of time. On the other hand engines can be knock limited where the  touque increases until it knocks. So to get the best you need to run on the edge of knock. Then you have fuel quality etc. one reason people use race fuels with a much tighter quality control. A properly tuned engine with a small safety margin that only uses fuel that is better than or of equal quality to what it was tuned on  has little need of knock control. On the other hand if you want to operate on any fuel with no safety margin then effective knock control is a must have. 

Just installing knock control as a lot do wont hurt but often provides a false sense of security as the installation is not verified but you never know your luck it could actually work well enough for your situation.

Sorry this is not really an answer as you would need to determine if it is of benefit to your specific setup by actually doing it and doing it properly may cost you an engine. I am pretty sure Porsche did not consider knock detection when designing any other part of the engine/gearbox and accesorie etc. which makes the task even more difficult and the results when using bolt on the side sensors unpredictable. 

[Peter M]

6 hours ago, Redracn said:

One of the most time consuming and potentially expensive jobs is proving that the knock system on any given engine actually works and can detect low levels of knock over a wide range of conditions.

I an not aware of any AC Porsches with a aftermarket known properly functional verfied knock control system using bolt on sensors but they could exist. 

Not all engines are knock limited. 

A properly tuned engine with a small safety margin that only uses fuel that is better than or of equal quality to what it was tuned on has little need of knock control.

Just installing knock control as a lot do wont hurt but often provides a false sense of security as the installation is not verified but you never know your luck it could actually work well enough for your situation.

I am pretty sure Porsche did not consider knock detection when designing any other part of the engine/gearbox and accesorie etc. which makes the task even more difficult and the results when using bolt on the side sensors unpredictable. 

Mmmmm, you've given me more to think about Red!

Reading between the lines suggests that any efforts to protect from knock would be better placed invested in converting to twin plug heads to allow lower levels of advance at peak torque in the first place.

Would that be your view too?

Thanks

Peter  

[Redracn]

18 hours ago, Peter M said:

Mmmmm, you've given me more to think about Red!

Reading between the lines suggests that any efforts to protect from knock would be better placed invested in converting to twin plug heads to allow lower levels of advance at peak torque in the first place.

Would that be your view too?

Thanks

Peter  

If you just want to drive it I would get a nice safe tune and hit the road. If you like to tinker and want to learn about this stuff then heads/and or knock control would be a good way to go with ITB. If you are racing then getting a good tune on racing fuel should do as I doubt you will be knock limited and other mods such as cams/pistons etc can make bolt on sensors not suitable due to the increased level of background mechanical noise. 

These days tuning the fuel is relatively easy once you know the target Lambda(A/F Ratio) for peak torque at given rpm and can be done by driving the car or from data logging. You will need a dyno to get the target Lambda but there are good rules of thum for this. With a known working knock system you can also get a reasonable ignition map on a knock limited engine this way.  But the only way to do the ignition properly is on a speed controlled Dyno so you can peak the torque while the engine is monitored by an expert human ear via a headset and special electronics $ or a known properly working knock detection system such as direct cylinder pressue measurement $$$ or special washers under the spark plugs $$ as well as find the engines knock limits. 

[x-faktory]

 

Greetings,

                    Here are the specs for the injectors that are typically used on the Triumph Speed Triple t'bodies. But, as it has been mentioned, Bosch injectors also work very well.

I appreciate the work done regarding the overview of systems available.....however, i would like to point out that I provide systems ranging from my original Speed Tripe/M'squirt based systems, to PMO ITBs and AEM Infinity (Rasant) systems and everything in between. My approach is to provide as complete a system as i can and it is focused on the DIY peeps out there, so every attempt is made to also provide good start up files, documentation to cover install and tuning....and tuning support via email, etc. Feel free to contact me, if wanting to put together a system or to discuss your projects.

Here is a video of my most recent project....beautiful 73 with 3.2....out with the old intake and Motronic, in with PMO ITBs and AEM/Infinity engine control. It is a good thing...running very strong.

regards,

al

Al Kosmal
the x-faktory
koz@x-faktory.com
RGruppe #669

www.x-faktory.com

[Cheshire Cat]

On 12/18/2017 at 9:04 AM, x-faktory said:

 

Greetings,

                    Here are the specs for the injectors that are typically used on the Triumph Speed Triple t'bodies. But, as it has been mentioned, Bosch injectors also work very well.

I appreciate the work done regarding the overview of systems available.....however, i would like to point out that I provide systems ranging from my original Speed Tripe/M'squirt based systems, to PMO ITBs and AEM Infinity (Rasant) systems and everything in between. My approach is to provide as complete a system as i can and it is focused on the DIY peeps out there, so every attempt is made to also provide good start up files, documentation to cover install and tuning....and tuning support via email, etc. Feel free to contact me, if wanting to put together a system or to discuss your projects.

Here is a video of my most recent project....beautiful 73 with 3.2....out with the old intake and Motronic, in with PMO ITBs and AEM/Infinity engine control. It is a good thing...running very strong.

regards,

al

Al Kosmal
the x-faktory
koz@x-faktory.com
RGruppe #669

www.x-faktory.com

Thanx Al for your input, I hope it`ll be quite helpful for everyone. And thank you for your work, you are basically a role model (at least for me) in meanings of ITBs  

[Cheshire Cat]

added another manufacturer (local one)

[Mike D'Silva]

On 13/11/2018 at 17:31, Cheshire Cat said:

added another manufacturer (local one)

I think Al is looking to distribute the Racehead ITBs in the usa soon...

In fact, here is it.. https://www.x-faktory.com/store/p4/EFI_Kit_S3-EFI-002.html

and yes, that is a photo of my motor during the first incarnation of the install

[MFX]

That is a very nice looking bit of gear. 

[Cheshire Cat]

A little update on ignition