Home built Hot Rod

[P-Kay]

Slow and steady wins the race....Was good to follow along your journey. Enjoy it buddy!

[MFX]

6 hours ago, Coastr said:

I remember when you first started posting I thought ‘can’t he just post some pictures like a normal person?’

Now I watch every week like a weirdo.

Well done - can you explain why the 100k is so important?  I assume it’s ore than a plaque.

Haha. It really means nothing. The plaque is the main thing, but besides that it is just a milestone.

[Stepo]

Good effort mate, I've greatly enjoyed watching your progress and learning a lot of your handy tricks along the way.  I've got a few years of working to go yet () but hope to restore a car myself in my later years and will be going back over your old posts to refresh, thanks for the inspiration and enjoy that baby!

[Coastr]

7 hours ago, MFX said:

Haha. It really means nothing. The plaque is the main thing, but besides that it is just a milestone.

Ok I remember the skid factory making a noise about getting to 100k as well and thought maybe it increased monetisation opportunities or something.

[MFX]

1 hour ago, Coastr said:

Ok I remember the skid factory making a noise about getting to 100k as well and thought maybe it increased monetisation opportunities or something.

It does look better for sponsors, etc, but to be honest subscribers really mean nothing at all. Views are much more relevant as to how a channel is performing. That is also the metric on which you make revenue.

[MFX]

Now Harry 911 is a running driving car, it is time to start tidying up some of the things that have been bugging me on the interior. First step is to build a custom floorboard.

 

 

[Carrera28]

Congratulations on hitting 100k subscribers 😎

[MFX]

13 minutes ago, Carrera28 said:

Congratulations on hitting 100k subscribers 😎

Thanks mate.

[MFX]

This week I look into the issues I had with Harry 911 on the Dyno and attempt to diagnose them.

 

 

[Peter M]

Jeff,

A couple of suggestions:

Are you sure you have a problem?  I know you flash up that overlay of those two dyno runs that show a discrepancy between them but are you sure you are comparing apples with apples?  Temperature, air pressure, humidity, tyre pressures and how the car is strapped down can effect readings.

It is normal for a twin spark engine to slow when you disconnect one bank of plugs as you are effectively slowing the rise in combustion pressure by doing so.  If there was no effect, there would be no advantage in having twin spark!  The important thing is that it's not missing and all the plugs appear to be firing.

Good idea to use ramp runs.

Your Link Extreme ecu has onboard data logging.  Instead of messing on with videos for data recording, the ecu will able to give you very accurate time information from when you go WOT from 2000rpm until you throttle off at redline.  Doing this in  3rd would give you better data as it is a higher load and the time period will longer and better reflect changes in tune as you go along.  Unfortunately this might also get you arrested so I understand if 3rd at redline maybe a bit too fast in your neighbourhood!

The onboard data logging will also show  instantenous Lamba, throttle opening, manifold pressure, air temperature, ignition timing, rpm, fuel pressure, voltage and knock activity all against an accurate time scale. 

I suggest you download this data and look for anything unusual. It would be useful to post these logs and see what comments you get back.  One or two comments might even be useful! 🤣

If everything looks fine, only then change one thing at a time and see the effect on your acceleration time. (INSERT CAUTION OF RISK OF POSSIBILTY OF DETONATION DAMAGE HERE).

 

Love ya work as always and hope my comments are useful.

   

EDIT: Actually recall Andre's explanation of ramp runs was useful:

Road Tuning | Ramp Runs On The Road Or Track [FREE LESSON] - YouTube

 

[Mike D'Silva]

nice one Peter. 

I thought all the same as you and was halfway through typing... you beat me to it and explained it better than I could. 

 

[Peter M]

3 minutes ago, Mike D'Silva said:

nice one Peter. 

Thanks Mike!

I think you and I should volunteer to give an unbias opinion.  You would be up for a drive of the HBHR on some of those nice roads around Jeff's place?  I'm sure he would be happy to put us up for the night or two as well! 😊

[Mike D'Silva]

I wonder if any changes were made to the tune between dyno runs too? I remember some videos where Jeff was watching things being changed live.. by the Link guys I think.. but not sure if that continued at all, after the first dyno tune was performed. I still say, time to get a decent set of performance header, and run open pipes on the dyno, to see what the motor can really do.. then muffle it to make it livable. 

And yes, with the current exchange rate, the USA definately get more HP than we do.. they claim 250hp atw with a 3.0 sC motor with nothing but a 964 cam and a noisy muffler.. yah, right.

 

[OZ930]

RPM drop is normal as PeterM suggests. It is actually a normal pre-take off run-up check in a piston aeroplane, at 1700 RPM, to turn off one magneto and confirm that you get 100-150 rpm drop, to confirm that a magneto and plugs are operating, then back to both mags and check that the rpm returns to 1700, then turn off the other mag and check for the same drop. Any rough running and excessive drop indicates a dead or fouled plug.  No drop  on one could indicate a “live” magneto.

Slightly off topic but may give you some confidence that your spark system is operating normally.

[MFX]

9 hours ago, Peter M said:

Jeff,

A couple of suggestions:

Are you sure you have a problem?  I know you flash up that overlay of those two dyno runs that show a discrepancy between them but are you sure you are comparing apples with apples?  Temperature, air pressure, humidity, tyre pressures and how the car is strapped down can effect readings.

It is normal for a twin spark engine to slow when you disconnect one bank of plugs as you are effectively slowing the rise in combustion pressure by doing so.  If there was no effect, there would be no advantage in having twin spark!  The important thing is that it's not missing and all the plugs appear to be firing.

Good idea to use ramp runs.

Your Link Extreme ecu has onboard data logging.  Instead of messing on with videos for data recording, the ecu will able to give you very accurate time information from when you go WOT from 2000rpm until you throttle off at redline.  Doing this in  3rd would give you better data as it is a higher load and the time period will longer and better reflect changes in tune as you go along.  Unfortunately this might also get you arrested so I understand if 3rd at redline maybe a bit too fast in your neighbourhood!

The onboard data logging will also show  instantenous Lamba, throttle opening, manifold pressure, air temperature, ignition timing, rpm, fuel pressure, voltage and knock activity all against an accurate time scale. 

I suggest you download this data and look for anything unusual. It would be useful to post these logs and see what comments you get back.  One or two comments might even be useful! 🤣

If everything looks fine, only then change one thing at a time and see the effect on your acceleration time. (INSERT CAUTION OF RISK OF POSSIBILTY OF DETONATION DAMAGE HERE).

 

Love ya work as always and hope my comments are useful.

   

EDIT: Actually recall Andre's explanation of ramp runs was useful:

Road Tuning | Ramp Runs On The Road Or Track [FREE LESSON] - YouTube

 

One of my Patrons also suggested taking a log and I didn't even think of that. That is much more repeatable. 

There were changes made to the cold start side of the tune between dyno runs by Adam at Link, but the power side wasn't messed with.

I think I do need to try a better exhaust on the car and see if that makes a difference.

Maybe I am chasing nothing. I believe now that I was misguided by thinking that removing one bank of plugs wouldn't have made a difference. Maybe that is just what this engine makes. It was the drop in power across the rev range that had me questioning, as both days were similar temperatures, with the same tuner, and as Neil mentioned, he would have thought it may have actually gained a little after the engine has loosened up after a couple of thousand kms.

Either way, the car is still great to drive and puts a grin on my face every time, so it is not the end of the world if the figures don't add up.

[michel]

7 hours ago, MFX said:

 

....Maybe I am chasing nothing. ....

Either way, the car is still great to drive and puts a grin on my face every time, so it is not the end of the world if the figures don't add up.

Maybe it’s time to lighten up and. Start a new chapter in Harry’s story - trim the fat so too  speak .
 

now I’m on no way suggesting  you’ve become more rotund, as we have all grown,  as we watched  your utube barn stormin antics. However power to weight always thrilling Too chase 

I enjoy your work sir 

 

[Peter M]

12 hours ago, MFX said:

I think I do need to try a better exhaust on the car and see if that makes a difference.

Jeff,

I'm no fan of your exhaust too but I wouldn't change your exhaust until you are completely satisfied everything is OK with your current setup.  Changing the exhaust potentially confuses things further as you then lose the validity of the data behind that baseline dyno run that is the reason for your current anxiety!

The only other reason I can think of in addition to the other possibilities I posted yesterday is that the engine suffered overrev damage sometime after the "golden" dyno run and before the 7,000rpm dyno pull.  However I would think some bent valves would be noticeable in deteriorated idle and starting quality.  That fortunately doesn't seem to be the case.

I agree with Michel, you've invested a lot of time into this project and its probably time to just enjoy it for a while.  You can always go back to your tuning tables at a later date.

 

 

 

 

[OZ930]

Could the cruise control somehow be interfering with the performance?  It uses the same brain. Doesn’t it ?

Random thought...again 🙄

[st3ve]

A couple of thoughts from another enthusiastic learning-by-doing amateur.  I injected a 1970's 3 cylinder 2-valve air cooled 1130cc bike engine and ended up with 100rwhp so kinda similar.
First of all yeah, data logging, explore that menu in your ecu software, I used it extensively in addition to a few dyno days when setting up.
Regarding the idle dropping, twin plug old-skool chambers require less advance than a single plug, so your tuning will have been set to suit the twin plugs. If it's anything like my ECU, it'll have an idle table and a target idle speed and certain trims it can use to try to maintain the idle.  But there are also limits on how much it can trim outside the expected settings, this is so it doesn't inadvertently melt the engine adjusting for a bad sensor or something.  So anyhow, by dropping back to a single plug idle, the ecu can possibly not compensate enough to maintain the target idle speed and it is not actually a problem.  Link should be able to confirm if that is anywhere near the mark.
Third thought was about the MAP sensor - I don't recall but didn't you fit that quite late in the piece?  Was it before or after the first dyno run?  If it has been added subsequently, the ECU could be doing something quite differently to before, like pulling advance out.  Datalog your main power dyno runs next time so that you know everything the engine is doing at the time and can compare from one to another.

HTH, always enjoy your exploits.

[MFX]

8 hours ago, OZ930 said:

Could the cruise control somehow be interfering with the performance?  It uses the same brain. Doesn’t it ?

Random thought...again 🙄

Haha... no, cruise won't effect anything

8 hours ago, st3ve said:

A couple of thoughts from another enthusiastic learning-by-doing amateur.  I injected a 1970's 3 cylinder 2-valve air cooled 1130cc bike engine and ended up with 100rwhp so kinda similar.
First of all yeah, data logging, explore that menu in your ecu software, I used it extensively in addition to a few dyno days when setting up.
Regarding the idle dropping, twin plug old-skool chambers require less advance than a single plug, so your tuning will have been set to suit the twin plugs. If it's anything like my ECU, it'll have an idle table and a target idle speed and certain trims it can use to try to maintain the idle.  But there are also limits on how much it can trim outside the expected settings, this is so it doesn't inadvertently melt the engine adjusting for a bad sensor or something.  So anyhow, by dropping back to a single plug idle, the ecu can possibly not compensate enough to maintain the target idle speed and it is not actually a problem.  Link should be able to confirm if that is anywhere near the mark.
Third thought was about the MAP sensor - I don't recall but didn't you fit that quite late in the piece?  Was it before or after the first dyno run?  If it has been added subsequently, the ECU could be doing something quite differently to before, like pulling advance out.  Datalog your main power dyno runs next time so that you know everything the engine is doing at the time and can compare from one to another.

HTH, always enjoy your exploits.

The MAP sensor was installed between, but the tuner set it up at the time, so it shouldn't effect the power run.

[LeeM]

 You have cruise control? 😳 Crikey

[MFX]

17 minutes ago, LeeM said:

 You have cruise control? 😳 Crikey

Yep. Although now I have perfect cruise control on Harry, the cruise on my 996 has stopped working. I have done a bit of research and I think it is probably just a faulty clutch or brake switch, so I need to do some more fault finding

[OZ930]

54 minutes ago, LeeM said:

 You have cruise control? 😳 Crikey

He has an electronic one where most of us have an organic one installed in the left seat and when the overspeed alarm goes off, it really goes off 🤣

[LeeM]

4 hours ago, OZ930 said:

 most of us have an organic one installed in the left seat and when the overspeed alarm goes off, it really goes off 🤣

 I've never had that 'feature' in mine. If I did, it would be disconnected sharpish! 

[MFX]

In this video I give you an update on Harry's progress over the last few months and build yet another exhaust system, to hopefully this time sort out my power restriction.