Aftermarket Aluminium Radiator Core/Shroud/Fan

[Banjo]

I don't know what it is, that has me, so fascinated with the concept of trigger wheels, & improving the accuracy of timing of engine fuel injection, & spark timing.

I'm fascinated, that in these days of EV, & the cries of the end of ICE engines; by the continued development of the Free Valve engine, in Sweden; where the timing of each valve can be individually timed.      https://www.freevalve.com/about-us/          https://www.youtube.com/watch?v=OZWeNPi2XkE

https://www.freevalve.com/freevalve-technology/        https://www.youtube.com/watch?v=XV4NavUIznc

However, the current ICE engines, & our olde K Series, have a mechanical camshaft, that dictates exactly when the valves open & shut, irrespective of whether the engine is idling; or running at 5000 rpm.

What we do have; is the ability to change the point in time, when the spark plug fires, & the compressed air & fuel mixture "explodes", & forces the piston back down. However, that ability to advance or retard the spark event, is controlled by those bob weights & tiny little springs, that lie "hidden" under the plate in our Bosch & Denso distributors.  As well as that, the points in the distributor, that  determine the point at which the spark plug fires, are not directly driven by the the crankshaft. In between the crankshaft, & the distributor, are two sprockets; a camshaft chain; & a set of helical gears between the distributor & the camshaft; all which develop slop, & therefore timing errors; particularly, when our 5K engines are 20-50 years olde !

It is therefore, a no brainer, to be able to time the ignition triggering directly off the crankshaft, where all that slop in camshaft & timing chain cogs, have absolutely no effect, at all.

I have a large timing disc, on the flywheel of my 5K test engine, with a strobe light. When the engine is running with the 5K dissy, you can actually see the trigger point moving about back & forth.  When the engine is controlled by an ECU, with a crankshaft fed trigger signal, the strobe on the timing disk is "rock solid", & steady. 

When I first started playing with this years ago, my early experiments involved using the starter motor teeth, on the flywheel; as a indication of where the engine was in it's cycle. Unfortunately, the number of teeth around the flywheel peripheral, are all; not equally divisible by 360 degrees.

The idea of fitting a separate large trigger wheel, to the opposite side of the flywheel to the clutch, is still one, I might revisit, as trigger wheels on the crankshaft pulley, are prone to damage in rally cars, & therefore avoided by many, in that sport.

So accuracy is everything, & you can have the most sophisticated & expensive ECU, but if the trigger signal feeding the ECU, is not stable or accurate, then the adage "rubbish in; rubbish out", comes to mind.

I personally don't favour the missing tooth concept, for a trigger disk.  My first sojourn into this area, used a missing tooth trigger wheel.  The problem is that the ECU sees the trailing edge of the tooth, before the gap, or missing tooth. From the frequency of the pulse chain, to that point, the ECU expects the next pulse to arrive at a certain duration, after the last pulse.  It does this for every pulse presumably. If the pulse is not forthcoming, the ECU assumes that this is the missing tooth.  The problem with this assumption; is that a missed pulse, could be resulting from an excessive air gap; or squaring of a VR signal, or a VR signal, at low rpm; & will be interpreted by the ECU as the missing tooth. 

The engine, then loses its firing / injection synch.

My assertion, from experience; says that the pulse from a Hall Effect sensor, & imbedded magnet, is a much more reliable scenario, in missing tooth control arrangements.

However, wouldn't it be better, if it was possible to get the same result as a missing tooth system, that worked well,  . . . . . without having a missing tooth at all.

I have been able to achieve this, because of the Haltech Hall Effect sensor I have, that actually has two Hall Effect sensors; with two outputs, in the same housing.

One sensor provides an output to "south pole" magnets faces, whilst the other sensor provides an output to "north pole" faces.

I fitted 35 magnets to my 36 "tooth" aluminium wheel, with the south poles facing the Hall effect sensor. In the 36th hole I fitted the same magnet around the other way, with the north pole facing out.  So once per revolution of the crankshaft, I achieve this sync pulse, from the "north pole" sensor, without a need for the computations required by the ECU, to detect a missing tooth.  However, I hear you say; that the signal from the south pole sensor still has a missing signal/tooth; because it does not produce an output when the single north pole passes the sensor.  True; but the output of the south & north pole dual sensors, provide an identical type of output. If we logically "OR" these two sensor outputs in an "OR or NOR" logic gate, we achieve a continuous stream of pulses, with no missing tooth at all.   However, the north pole sensor, still provides a single pulse , for synchronisation, as to exactly where the crankshaft is in it's revolution, without the need to constantly keep looking for a missing tooth. 

Once I have this new aluminium trigger disk running, I'll post the CRO waveforms, & the description above will be clear to see.

The other consideration, is whether there are any existing ECU decoders, that would cater for the arrangement, I am proposing.  If not, the the exercise, becomes very analytical, but not very practical.  I've been a great advocate of the Speeduino, EC, designed by Josh Stewart, in Ballarat Vic.

In the decoders supplied standard with Speeduino firmware, is a decoder called a 'Dual Wheel" decoder.  

https://wiki.speeduino.com/en/decoders/Dual_Wheel

It is described as follows . . .

Quote

A dual wheel trigger is one where there is a primary multi-tooth wheel combined with a secondary single pulse to provide location information. The primary input should contain no missing teeth. Both pulses can run at either cam or crank speed, but sequential operations requires that the secondary pulse is located on the cam. The design of the secondary trigger can vary (Eg a single short tooth, half-moon wheel etc), provided it only provides a single pulse per revolution. As with other arbitrary tooth count wheels, the number of teeth must evenly divide into 360 (or 720 if running at cam speed).Tooth #1 is defined to be the first tooth on the primary wheel AFTER the pulse on the secondary wheel.

This decoder suits my trigger wheel design & outputs perfectly, if you are using a batch firing ignition/injection arrangement.  However, it is easy to

provide sequential ignition & injection operation, by "ANDing" the single pulse per crankshaft revolution, with an "overlapping pulse", from the camshaft positional sensor.  It that way, we get a single pulse every 2 revolutions of the crankshaft, which allows "sequential" operation, of the ECU. 

As soon as I get this new aluminium trigger disk built, I will try this out, as at present, I can not think of anything, that will prevent this from working. 

In theory, you could actually lose altogether, the camshaft pulse per 2 off crankshaft revolutions; & simply flick a switch & run the engine in a "batch" mode.

 

Cheers Banjo 

 

 

 

 

 

 

Edited April 1 by Banjo

[Banjo]

Well, my new "rare earth' magnets haven't arrived as yet, but I have made a 'logic interface", for the Hall Effect sensor, to "mix" the pulses from the two  (2) Hall Effect sensors, so I get the exact 36 continuous pulses per revolution, without any missing teeth, & a pulse, once per crank revolution, which is all that is needed for wasted spark operation.   However, if we "AND" the camshaft pulse & the single north pole pulse on the aluminum disk, the end result is a single pulse once per 2 revolutions, which will facilitate/allow, full sequential ECU operation.

 

 

It looks so clean & simple, in practice; as there is only one (1) Hall Effect Sensor housing; but inside it actually has two (2) Hall Effect sensors, side by side, with separate outputs. One output reacts to the "35" off "South" poles, & the other to the "1" "North" pole.  Not a "missing tooth"/magnet in sight, which should reduce the overhead of code, that is constantly in play; trying to detect the missing tooth.

I've had it working on the bench all weekend, & the oscilloscopes traces indicate it is working perfectly.  The single camshaft pulse, per camshaft revolution, will be made slightly wider that the single crankshaft pulse that indicates where the crankshaft is in it's rotation. That single pulse signal, is in perfect synchronisation with the primary 36 pulse train, as you can see in the trace below.

Below is a full rotation of the crankshaft, showing the single pulse per revolution, with no missing teeth / magnets; in the main pulse train.

The trace indicates there are just 18 pulses per revolution (not 36 off), as the small variable speed electric motor on my bench; used for this testing, is using a smaller 150mm disk, with 18 off pulses per revolution.

Many of the missing tooth trigger wheels, have more than one missing tooth, & sometimes in two or three difference places.  This is so the "synchronisation", can be achieved in less than 2 revolutions, of the crankshaft.  This is primarily used when cranking the engine, to start it; to allow ignition firing, within the first revolutions of the crankshaft.  If you want or need to delve into why there are so many different trigger wheel "missing teeth" variants; & you've got an hour to spare, then this webinar on utube, with Josh Stewart, is a good information source.

https://www.youtube.com/watch?v=Iv4xvBVqQ6g

I will position the aluminium trigger disk on the crankshaft, so the the single synch pulse (north pole) occurs 90 degrees before TDC No: 1 cylinder.

Hopefully, the Dual Wheel decoder, in the Speeduino ECU, will handle this arrangement perfectly. If starting the engine, becomes a serious issue, I will look at other ways to possibly synchronise the ECU with crankshaft actual position, within half a revolution, which is the best possibility, that is attainable.

P.S.  The three (3) off MOC5007 IC "opto couplers" are optional; but I have used them to optically isolate the Hall Effect sensors & their 12V supply, from the 5Vdc & logic  circuitry, so that any noise in the 12 volt system, is minimised.  I've used this arrangement for some time, with excellent results. I could also have just carried out any logic required, for generating the two vital output pulses for the ECU, with a simple little programable microprocessor; but the logic was so simple, that it seemed much simpler, to just utilise, two (2) cheap fixed logic gate chips.

Cheers Banjo

 

 

Edited April 2 by Banjo

[Banjo]

So first step on a wet Saturday; yesterday in "the shed", was to transpose the "camshaft sprocket cover", onto the 5k engine.

I've swapped back over to the original 5K crankshaft pulley, as it was designed to minimise harmonic  imbalance in the crankshaft itself (I believe)

This will require a longer fan belt, but that is not an issue.   The main concern, & requirement, for sensing the imbedded magnets, on the outer rim of the trigger wheel, is "concentricity"; so the gap between the the outer edge of the aluminium disk, & the tip of the Haltech Hall Effect sensor, is very uniform. The use of very strong rare earth magnets, with a rating of N45 or greater, should provide greater tolerance, or slight run-out of the disk. You can take out the Hall Effect sensor, & stand above & look down the hole, in the mounting bracket; & see how well the edge (width) of the aluminium disk, is centred under the hole.

I have place several large washers, directly behind the aluminium disk, to space it slightly away from the edge of the crankshaft pulley.  These washers, also allow the disk, to be moved backwards, or forward, to accommodate the thickness of the disk.  I'm currently using a 6mm thick disk, but the latest disk, I have just aquired is 8mm thick; & I've now just learned, of where I can obtain a 10mm thick one, if I need it, to be able the drill holes in the edge of the disk, to accommodate a larger diameter rod rare earth magnet. 

 

The next part of the exercise, is to create a wide camshaft position pulse, that can be  logic "AND"ed, with the single North pole single on the crankshaft disk, to provide a single pulse per two (2) revolutions, of the crankshaft, for sequential ignition & inject operation. 

I have three (3) options, in this regard.

(a) Use the existing cam position sensor I have created using a a "gutted", olde Denso distributor body, with dissy cap removed,  & replaced by a "jam jar lid".

The pulse will simply have to be larger in width, than the single "north" pole pulse from the crankshaft.

(b)  Use the Hall Effect sensor, I have fitted to the camshaft cover, detecting a rare earth magnet attached to the camshaft sprocket.  This has one advantage that, both crank & cam Hall effect sensors, would be mounted on the same camshaft sprocket cover, & would look simple, neat, & very purposeful. Now the camshaft one, that is already been in place for a couple of years, has not given an "ounce of trouble". However, if it real-life, you had to get access to the magnet assembly; on the camshaft sprocket; it would be a very difficult job, to remove the camshaft sprocket cover, with the engine, in the engine bay.

(3) I've come across a reference on the net recently, of someone using the camshaft lobe tip, for driving the mechanical fuel pump, to trigger a Hall Effect device. I daresay, it would work alright, even though the lobe in the K series engines, doesn't directly point towards the middle of the mounting point opening, on the side of the block. However, & don't particularly fancy the Hall Effect sensor, operating reliably, in that very hot environment, being constantly "splashed", with hot oil.

I think, with those restrictions, the gutted dissy shell that I have already made, will be the way I go initially. Unlike the other two alternatives, "a" & "b", there is no issue with access, or being in a constant hot & oily environment.  All i have to do, is maybe install a rare earth magnet, with a wider face, so the the pulse width of the cam position sensor overlaps the single "single north pole" crankshaft pulse.

Anyway, I currently will have a knock sensor attached to the unused mechanical fuel pump mounting point, so that option is out

So that's the objective for today; & then it will be time to pull the camshaft sprocket cover off, & build an "all aluminium" mounting block, for the primary, Haltech dual Hall effect sensor.

Cheers Banjo

 

Edited April 7 by Banjo

[altezzaclub]

Hmmm... what did you learn from that knock sensor Banjo??  It has crossed my mind occasionally, but knocking in a non-turbo car is not so serious so I hope I can hear it before its too bad. I think we just get the fast-flame-front knocking from the spark being too early rather than the explosion before the spark plug fires that a turbo can get.

[Banjo]

Haven't actually tried it as yet.  Some modern ECUs have an input for a knock sensor, & automatically lower the advance a little until the "knocking" is no longer detected.  It allows you to get fairly "aggressive, with the advance table, while "learning" the engines characteristics, without running the risk, of doing any damage.

I need to make up a little 6kHz filter, so I can see it on the oscilloscope.  

Cheers Banjo

[Banjo]

When I took the 5K engine camshaft sprocket cover off, on my 5K EFI project, to swap it over, for the one which will have the Hall sensor mounted on it, I noticed this nice new dual chain & sprocket. I'd completely forgotten that I'd replaced it with an aftermarket one, some years back, when I first set up this 5K test rig.  I was always a bit miffed, with Toyota; that the two off 5K engines I had, only had, single width link camshaft chain drives, when even some of my olde 3K engines had dual chain camshaft drives. However, this new "aftermarket camshaft sprocket", was a dual chain model, & had a total off nine (9) holes, into which the location pin on the front end of the camshaft could be located.  They were stamped labelled  . . . .

4R -3R - 2R - 1R - 0 - 1A - 2R - 3R - 4R     It appears that they represent 1-4 degrees Retard; & 1 - 4 degrees Advance, with "0" in the middle being standard/factory/design camshaft timing. The problem with selecting an advanced or retarded camshaft timing; is that only one end of the engines range is improved; whilst the other is slightly poorer. 

I assume the advance, would assist, the low rev range & produce more torque; which would make sense; as 5K engines, were basically used in commercial Liteace vans, & Toyota forklifts, right up until the year 2000, I'm led to believe.

I Googled it, to see if my assumptions were right, & lo & behold, up came the following page.

https://www.rollaclub.com/board/topic/82434-4k-timing-chain/

I trust You've watched the links I posted about the FreeValve engine (earlier in this thread), which points out, that when you have "complete control" over the opening, closing; & rate of opening or closing; that you then have total control over the combustion process, which accounts for the incredible extra horsepower, they are able to extract from from a given C.C. capacity.  The proof of this statement; is in the results you obtain from a race engine, with an aggressive camshaft grind; where the engine outputs more at high revs, but sounds like a olde steam engine, at a high idle.

I gather that's why a number of engine manufacturers; like Toyota, changed their valve timing to two different ranges with the VVT timing engines like our family's daily drive; Echo & Corolla engines.

I'd love to be able to adjust the camshaft timing, to provide ideal engine performance, in the 2500 - 3500 rpm range, which is where my KE30 with 5 speed gearbox & BW diff, currently sits when cruising; but it is such a "pain in the arse", to remove the timing chain cover, with the engine out, on a test bed; let alone, in the engine bay.

It is so much easier to experiment with camshaft "inlet & exhaust valve timing", on twin overhead heads, as you can just move the toothed belt, clockwise or counter clockwise, on the toothed pullies, at the front of the head.

The modified 5K camshaft sprocket cover, is almost ready to go back on the engine, as I've now added a bracket for the dual Haltech Hall Effect sensor.  I will move the camshaft advance  2 degrees, & we'll see what effect that has.

The round disc, permanently fitted to; & now an integral part of the timing chain cover; is necessary, so the stainless steel bracket, mounting the Haltech dual Hall Effect sensor face is exactly square to the edge of the aluminium disc. Although the simple stainless steel bracket is only adjustable in "one plane", the centering of the Hall effect sensor, over the edge profile of the disk, is easily adjusted with 2-3 large washers, behind the disk, where the crankshaft center bolt, attaches to the crankshaft, & the crankshaft pulley.

Just awaiting, the ebay arrival of 50 off rare earth "rod" magnets; 36 off which, will be inserted into the edge of the disc; exactly 10 degrees apart.  The whole exercise, is quick clean & simple, now that it is finished; & I'm pretty excited about actually running the engine, & see what the pulses look like. 

This simple setup, will allow "batch fire mode", from the Speeduino ECU; but my first job after this is up & running, will be to enlarge the width of my camshaft position sensor, built into an olde Denso dissy; that will "overlap" the single pulse per rev; from the crankshaft disc, & result in a single crankshaft pulse, once per 2 revolutions of the crankshaft.  That will allow full sequential control of both spark plugs & fuel injectors.  Lots of fun had; bringing an olde engine up to modern day precise control of both ignition & fuel.

Cheers Banjo

 

 

 

Edited April 21 by Banjo

[Taz_Rx]

That's a Roll master adjustable timing kit. I've got one in my motor. 

From memory each hole you advance or retard the timing gives 6° of timing change and will move max power 100rpm up or down the rec range.

[Banjo]

Hi Si,

         I'll pull the sprocket off, before I move it; & with a protractor; measure the angular change for each positional change.  The total of 8 settings, for both advance & retard, appear to each be equal.  I'll then just double that number, as valve opening & closing lifts are always set as degrees of crankshaft; not camshaft.  I looked on the net, for the instructions for this particular Rollmaster model, which I believe is a CS9000, but could not see one.  Will have another look today.  I'll post my findings here.

Many thanks !

Cheers Banjo

Edited April 21 by Banjo

[Taz_Rx]

👍

Also note the numbers around the outside of the sprocket. That's the new TDC "dot" (lining up with the dot on the crank sprocket and for under the can sprocket)that corresponds to whatever new hole (for Cam dowel pin) you choose.

[Banjo]

Thanks Si,

                  I'm sure it will all make sense, once I pull it off, & reposition the camshaft sprocket on the end of the cam.  The rear of my 5K engine on the test bed, is exposed; & I have a large 360 degree wheel on the rear face of the flywheel. As it is easy to see, & was set up, with TDC no:1 cylinder being spot on; I should be able to confirm the opening on the inlet valve on No: 1 cylinder, before & after the moving of the camshaft sprocket.  I will advise, once I tackle it, this evening.

The 5K engine official engine power output specs, indicate it produced . . . .

Quote

The 1.5 L (1,486 cc) 5K was produced from 1983 through 1996. Typical output is 55 kW (74 hp; 75 PS) at 5600 rpm. Bore and stroke is 80.5 mm × 73 mm (3.17 in × 2.87 in). 

As it officially, developed 74 HP / 55kW, at 5600rpm; with standard valve opening & closing times; should I initially increase or decrease the opening of the valves, to increase the power in my "desired range" of cruising; at 2500 - 3500 RPM ?  ( have a 5 speed KE70 gearbox, in my KE30 ).

I'll do a bit of research, before I pick on a figure to;  "test the waters".

Cheers Banjo 

Edited April 22 by Banjo

[Taz_Rx]

Yeah cool, let me know as I've never moved mine off 0. More so got it as I just wanted a quality timing chain system.

55kw... So would that be wheel or flywheel? More than tripled that at the wheels hehe