Restoring #151489 - building a faux cam carrera

[Bill Sargent]

After I posted the rocket science screen shots I went back to page 1 of this thread and noticed a photo of my daughter, Hana, who was about 9 months old. Time flies as the attached photo taken at Christmas 2013 shows. Hana with her oldest sister Lindsey at a night market in Phuket, Thailand. Lindsey was about the same age as Hana is now when I started on the 10 year restoration of my 64C cab back in 1989.

Hana at 4.5 years and Lindsey at 28 years

Hana and Lindsey Xmas 13.jpg (56.72 KiB) Viewed 6292 times

Training the next generation(s) of 356 drivers!

[Bill Sargent]

Now back to rocket science. 3D CAD being used to check clearances for injectors and fuel rail in the intake manifold cam box.

Image of new manifold with Pepco injectors and fuel rail in the cam box area.

3D Manifold 2.jpg (8.21 KiB) Viewed 6234 times

Image with the cam cover installed - fuel injection components fit with no problem. Fuel line will go in the end of the cam box nearest to the front of the car.

3D Manifold 1.jpg (6.55 KiB) Viewed 6234 times

And on a less technical front Ralfy has run one of the motors being built on a Dyno with 48mm Webers, 1883 cc etc. Seems to run well, but dyno had an issue and is being calibrated. More on that later. Thanks for following along!

[Bill Sargent]

Work has progressed quickly from 3D CAD on the screen to a 3D printed prototype intake manifold that will be flow tested. I will copy liberally from Nigel's update of a few days ago. In the photo below 3D printing is underway. The printer is laying down the support structure frame to support the main print....

FAux Cam Intake Manifold 3D print 1.jpg (29.23 KiB) Viewed 6167 times

The manifold had to be split into 3 pieces for printing due to the 8" by 8'' bench size of the HP printer. The manifold model was split in software called "Spaceclaim" and some dowel holes and pegs were added to the sections to allow them to be glued back together with perfect alignment. This photo shows two of the three pieces needed for the full manifold.

The next photo shows the complete printed manifold. The manifold ports will now be polished through with some 360 paper prior to flow bench testing. In addition to flow testing, the print will be used to check how the peco injectors and fuel rail fit and to start development of tinware. All of this will allow the design to be finalised prior to Jenvey making the mould tooling for casting the final part in aluminium. The manifold is designed to not extend laterally beyond the horizontal side tin. The new tin to be developed is to replace the vertical tin around the spark plugs on a push rod motor as well as the tin needed to mate up with the 4 cam fan shroud.

As you can see the process is rather quick. For any parts that can be painted plastic, reproductions could be made at home if you have the CAD software, ability and a 3D printer! And they already have industrial 3D printers that can print in aluminium and stainless steel - as the Brits say, "the mind boggles"! Thanks for following along!

[Steve Harrison]

The Future is happening,....Now!...Right here on this thread.
Wow Bill, incredible work.

You heard last year all this hype about 3D printing, but it has died down a little bit lately. Your application gives perspective on real world personal uses.

[Bill Sargent]

Nigel is continuing to work on the new intake manifold/cam box unit. The first 3D print provided several learnings:

1) A few interference points with the head fins were identified and fixed. There was also not enough material in the lower ports area to allow for the large intake ports Ralfy plans on his motor. To resolve both problems the cam box was moved forward and up.
2) Details have been added to allow for the cable routing for the injector controls.
3) The intake shape was also tweaked slightly to give smoother transition into the port.
4) Access for a spark plug socket was improved.
5) Material was removed from several areas to save weight and improve material flow when the mainfold is cast.

A partial second 3D print was therefore made to check all of the CAD changes noted above.

1/4 of the manifold 3D print 2 being test fit on a head. Injector port visible with boss that can be tapped to hold the fuel rail.

July Manifold 1.jpg (22.19 KiB) Viewed 5988 times

Another view of the 2nd manifold 3D print showing the base of the manifold and a boss that can be drilled for the injector cable.

July Manifold 2.jpg (20.87 KiB) Viewed 5988 times

View down the intake manifold from the top with the injector port just visible. Note that the top flange where the carb mounts was not printed.

July Manifold 5.jpg (22.69 KiB) Viewed 5988 times

View up from the bottom of the manifold with injector port visible.

July Manifold 6.jpg (17.57 KiB) Viewed 5988 times

Now that the 5 items have been cleaned up in the CAD world Jenvey are CNC machining the moulds to cast the frst 3 sets of manifolds - 2 sets for carbs and 1 set for fuel injection.

More to come. Thanks for following along. Hopefully I will see some of you at the West Coast Holiday. Ralfy and I are bringing both my cars, although neither with a faux cam motor yet.

[neil blaber]

following along with great interest

[Bill Sargent]

Got back to China over the weekend after a 2 week trip to the States. Managed to attend the WCH in Stevenson with both my cars, and had daughter #2 driving one of them. Great fun. Received the photo attached below yesterday from Nigel of the first casting of the fuel injection intake manifold. It is ready for machinging and then final fit testing before the other sets of the short run are made. if any of you are interested in having a pair made let me know offline and I will put you in touch with Nigel.

Manifold has just been cast. Shown with original cam cover.

Thanks for following along!

[Bill Sargent]

Received some more photos from Nigel that show the intake manifold and cam box machined, mounted on a head and how the fuel lines fit for a fuel injection installation.

Nice view of the manifold and cam box on a pushrod head. The cam box sits within the width of the side engine sheet metal, so the motor can be installed/removed with the manifold in place.

Side view showing how far out the cam box extends from the head.

View from the cylinder side of the head. You can see that the intake manifolds place the carbs closer to the center line of the motor. The design is to place the carbs in the same place in space relative to the shroud as on a 4 cam motor. Allows use of the 4 Cam throttle linkage to be used with Ibrahim Kuzu's 4 cam cooling set up. Note also the scallops to allow spark plug removal.

Shot showing fuel rail and injectors in place. Fuel lines are temporary mock ups. Final version of fuel lines will be much neater.

These manifolds will offer several options for getting fuel to the motor.
1) Stock Solex carbs can be used. The tops of the manifolds are made with sufficient material such that they can be ported from 40 mm to 44 mm.
2) Fuel injection can be hidden in the cam box as in the last photo above. Solex carbs can be used as throttle bodies or Jenvey throttle bodies may be used.
3) Fuel injection rails can be added to the Jenvey throttle bodies if someone likes that look as in the photo below.

Nice view of the Jenvey throttle bodies on the new manifold with a fuel rail and injectors mounted.

More to follow. Thanks for following along!

[Richard Dos Santos]

Awesome work! I love this thread. Keep up the good work!

[Bill Sargent]

So far you have seen the 3D print process to prototype the new manifolds and the first manifold casting. Nigel sent some photos showing the casting and machining process. The manifold with cam box and optional fuel injection is a complex casting and the moulds to generate the shapes have to be in multiple parts. The main body mould has removable sections to allow the inner cam box sand form to be moulded in a two stage operation.

This is the main mold with the second part for the cam box ends (where the distributors fitted on early cars) installed.

Shown below are the separate cores that are attached form the complex detail of the distributor mounting either end of the cam box.

Cam box end molds that are used with the main cam box mold

The computer generated and flowed (see previous posts) port shape is generated by inserting two sand cores into the main mould. The sand cores are formed via this mold.

Mold for sand cores of intake manifold flow path

Once the manifold is cast it gets placed in a 4 axis CNC milling station as shown below. This allows the manifold to be rotated about its axis to machine the required dimensions and shapes. In the 3rd machining operation the manifold is held vertically so the ends and the distributor bores can be machined. The camcover is fitted prior to machining to ensure a perfect bore and a matched set of cover and cam box is formed.

Freshly cast manifold at the start of the machining process

Development of the new manifold has only been possible through the assistance and considerable skill of Jenvey Dynamics. Mike Jenvey shown below is a keen racer and has turned his passion into a very successful business. His experience in creating injection systems for many manufacturers and race series has allowed us to create a manifold with confidence that it will perform well.

Mike Jenvey at the machining station

Next post will show how the manifolds fit on a pushrod motor with a 4 cam fan shroud. Thanks for following along!

[Bill Sargent]

Now that the first prototype manifold has been cast, Nigel is checking fit on a pushrod motor with 4 cam fan shroud. One of the challenges of the manifold design has been to get the carbs to sit in the right place relative to the fan shroud. The carbs on a pushrod motor sit about 1.5 inches further apart and lower than on a 4 cam motor. The other challenge was to ensure that the cam boxes did not overhang the periphery of the engine side tin pieces. This was necessary to ensure the motor can be removed without having to first remove the manifolds. It also leaves room for the gas heater ducting running down the passenger side of my engine bay. The series of photos below shows how things fit.

Detail shot of how the cam box sits within the side tin envelop

With the new manifolds bolted in place and the aluminium distributor plugs fitted the new carb/throttle body position becomes very evident and makes the whole engine look square like an original 4 cam.

New manifolds on motor with 4 cam fan shroud

Compare this with the normal pushrod solex manifolds in the photo below.

Stock solex manifolds on motor with 4 cam fan shroud

Diverging for a moment from the new intake manifold, the next photo shows Nigel’s version of the 4 cam generator stand and how the crankcase breather will be handled. Nigel's generator stand sits further toward the crank pukley end of the motor than Ibrahim Kuzu's reproduction of the original and mounts to the pushrod generator stand holes on the 3rd piece.

view of Nigel's gen stand that mounts to the 3rd piece and the pipe from the pushrod gen stand mount hole back to the early style breather. On my and Ralfy's motors we plan to have a custom cover for the gen stand hole with a 90 degree fitting to connect to a pipe running under the 4 cam shroud on the 1/2 cylinder side. From there a hose will lead up to a late style "cows udder" breather box on the firewall.

The next photo shows the breather pipe that runs from the 3rd piece to the correct 547 style breather for an early 4 cam motor. Nigel worked with Gerry McCarthy to ensuring that the original baffle design and shape replicated - many thanks to Gerry! On my motor and the ones Ralfy is building there will be a 90 degree elbow with hose going up to the later style "cows udder" breather box on the firewall.

shot showing how the pipe from the gen stand hole connects to the early 4 cam style breather. Manifold allows the breather to be easily disconnected to remove the motor (o-ring seals). Ports on the side are to allow venting of the valve covers.

And finally a couple of details shots of the nuts for the cam covers and the plugs for the ends of the cam boxes where the early distributors would normally mount.

Cam cover nuts with lock wire hole

Cam box end plugs

Nigel's next task is the final version of the injector fuel rail and creating the tinware to connect the 4 cam shroud to the area around the manifolds.

Having worked with Ralfy and me on our faux cam motors, Nigel now feels Ibrahim Kuzu has done such a fine job in reproducing the original 4 cam cooling system that it has to be the unit of choice when building a fauxCam motor, so his 4 cam generator stand will probably remain a 1 off. Based on the contacts and prototyping skills he has acquired on this and other projects, Nigel has formed his own engineering and technology company, with one of the product lines being parts to compliment Ibrahim’s 4 cam cooling system for the 356 pushrod engine. The other product in the works is an electronic reproduction of the Halda Speedpilot with many additional functions - contact Nigel for details. Thanks for following along!

[Greg Caron]

Bill,

I would like to ask you some advise in mp but can't find your e.mail.
Please contact me
Thanks,
Greg

[Bill Sargent]

Greg,

I have turned on the button in my profile that allows you to send me an email through the Registry site. Look at the bottom of my posts and click on the email button. I can then reply offline directly to you.

[Bill Sargent]

Bolts on to a Pushrod case. More details to follow.

90 Degree V Drive - view 1

90 degree V drive - View 2

Home for 90 degree V drive

[Bill Sargent]

In my last post I included a photo of the then current status of another sub project on my faux cam motor build – a 90 degree V Drive for use on a push rod motor. I have been busy at work lately and have not posted the follow up, but will now make a start on describing the design process that has occurred over the last one plus year. In late 2013 fellow Registry member Gregory Campbell contacted me to ask about details on the motor I have built for my project. Gregory, whose Devin Speedster you may have seen at the 2014 WCH, is having a 904 replica built and he wanted the appearance and power of a 4 cam appearing motor for the project, but without the 4 cam motor cost. Gregory also owns an Elva Porsche with 4 cam motor, so has access to factory parts. Gregory’s 904 project led him to contact me about my faux cam motor design. After discussion, Gregory decided to clone my motor design using John Wilhoit’s 2132 cc kit for his motor. Gregory however did not want to go the crank fire faux early type V drive route Nigel and I had been going. He was interested in a functional 90 degree V drive that would look correct in a 904.

Gregory's motor built on a 912 case.

Compare Gregory's motor to mine. Very similar

Now I need to provide some history. Back in 2011, well before speaking with Gregory, I contacted Gary Okoren in Golden Colorado to discuss the 3rd piece and 90 degree V drive design he did for the pushrod motor used in Al Lager’s Abarth Carrera replica. I included a photo of the motor in Al Lager's Abarth a few pages back in this build thread. For those not familiar with Gary’s design, the new 3rd piece did away with the #4 main bearing, allowing the 3rd piece to be very thin. In addition the design moved the pushrod distributor drive gear out to the nose of the crank placed and moved the crank pulley to where the distributor drive gear had resided, just outside the new 3rd piece. The V drive was integrated into the new 3rd piece, with internal oil passages etc, and was driven by the gear on the nose of the crank. The V drive used pushrod distributor drive shafts and pushrod distributors recurved for twin plug use (advance limited). One drawback of the system was that replacement of the fan belt required removal of the entire V drive.

My reason for contacting Gary was to ask if he had considered a T shaft driven off the crank pulley nut like the 692/2 & 3 as well as 587 4 cam motors did. Gary said that time pressures prevented this, however they had thought about it. I then asked if Gary would be interested in modifying the design, but Gary said that this was really not his core business. Gary was however kind enough to provide me with the CAD file for the V drive body. I thought that at some point in the future I might try to modify the design for a T shaft drive system and mounting on a stock pushrod motor case. I then moved to China, hooked up with Nigel on the faux crank fire V drive system and forgot about the CAD file until Gregory and I started discussing his V drive wish list.

Gregory encouraged me to see what we could do with the CAD file, so I obtained a free 30 day trial version of the Autodesk Inventor CAD software. I had some previous CAD experience and found the software a little complex, but not too hard to use. At this point Gregory and I made a list of the modifications needed to the Okoren design:

1. Redesign the V drive body inner bore to hold the pushrod distributor drive gear on a newly designed internal drive shaft supported by the same size/type bearings as an original V drive and using original size oil seals.
2. Hold the internal shaft, bearings and oil seals in place with newly designed inner and outer end caps with provisions for shims to allow both pre load of the bearings and adjustment of the distributor drive gear position relative to the distributor drive shaft gears.
3. Design the drive shaft to be internally splined to accept an externally splined T bolt similar to the original which allows for the T bolt to be pulled out for easy fan belt changes.
4. Design a new mount frame to allow the V drive to be mounted and centered on a stock unmodified 356 pushrod motor case using longer studs for the upper two on each side that secure the 3rd piece to the case. Produce mount frame versions for 904 and 356 use.
5. Redesign of the remainder of the V drive body to allow for mating to the new mount frame, centering of the V drive to the crank
6. Redesign of the V drive body to accept external oil in/out connections. Also include an oil inlet restrictor plug as on original 90 degree V drives to control oil flow into V drive body.
7. Design a new splined T shaft to drive the V drive from a slot in the crank pulley nut.

With this plan in mind I procured the “light” version of the Inventor CAD software and we started with the V drive body design provided by Gary shown below:

Okoren/Lager V Drive design. You can see the large portions of the body to the right of the distributor tubes - they contain oil passages and allow mounting to the custom 3rd piece.

Front view of the Okoren/Lager V Drive. It mounted to the custom 3rd piece with 3 studs. The shafts that take the distributor are longer than on a factory V drive since this design uses pushrod distributors and the pushrod distributor drive shafts.

The extrusion on the lower side of the left distributor tube is an oil passage for the oil drain back to the custom 3rd piece.

The small hole you see in the "ear" to the left of the photo is the inlet for oil to the V drive from a passage in the custom 3rd piece. There is a 90 degree angle in this passage and oil sprays on the pushrod distributor drive gear that is on the nose of the crank.

The next few posts will follow the modification of the Okoren/Lager design to function more like the factory V drive. Thanks for following along!