Heavy Metal! Part Deux - The Carbon Copy

[Jonny042]

I finally got around to test fitting the sunroof plug. It fits great!

The gap around the perimeter is about 2mm. The perfect amount to fill with adhesive, but not so big as the be unmanageable.





Also did the final fitting and weigh-in of the hardware bits for the hinges. 10g! vs 28g for the factory bits. Note also the bushing in the hinge for the pivot bolt.

[Jonny042]

I've been busy with a few things of late, not project or car related. In the meantime, I've been trying to make sure something is happening on the project, even if it's a little thing, every single day.

More often than not it means buying a part, or researching something when I have a few minutes to spare.

Not so long ago I had four brand new GKN CV joints sent straight from Pelican Parts to a race shop that offers CV lightening services. The results were impressive:




Not a bad start, at least. This is a small part of a larger and heavier assembly - I have found a place to make axles to my specification at a reasonable cost, so combining hollow axles, the lightened CV joints, and a few other tricks I have up my sleeve will result in a total of 10 pounds saved off the axle assemblies!

When it comes to shaving off weight, 10 pounds is a pretty big deal, so I'm happy with that.

[Brookieslayer]

Originally Posted by Jonny042

I've been busy with a few things of late, not project or car related. In the meantime, I've been trying to make sure something is happening on the project, even if it's a little thing, every single day.

More often than not it means buying a part, or researching something when I have a few minutes to spare.

Not so long ago I had four brand new GKN CV joints sent straight from Pelican Parts to a race shop that offers CV lightening services. The results were impressive:




Not a bad start, at least. This is a small part of a larger and heavier assembly - I have found a place to make axles to my specification at a reasonable cost, so combining hollow axles, the lightened CV joints, and a few other tricks I have up my sleeve will result in a total of 10 pounds saved off the axle assemblies!

When it comes to shaving off weight, 10 pounds is a pretty big deal, so I'm happy with that.

Especially in the rear of the car… even though it is on the centre line of the wheel…

[Jonny042]

In the hierarchy of where you want to lose weight, it could be worse! At least half unsprung, a tiny bit rotating, and at the rear, so not bad!

At the absolute top of the hierarchy is anything rotating at crankshaft speed, I know that the crank and rods (lightweight Pauter) I am using are a full 6 pounds lighter than the 3.0SC parts in PHM. Also, I've rounded up clutch and flywheel components that are 4.5 pounds lighter than the Aluminum Sachs pressure plate and RSR style billet flywheel in PHM! So there's another 10+ pounds that I've identified in the best possible place.

I am using Project Heavy Metal as my benchmark, 100%. I pretty much know, or can find out, what every single part weighs on that car, so it gives me a means to quantify my progress as I go. That car was 2200lbs, (999kg!).

I do need to figure out a way to present it as a running total in the thread somehow. Probably just a half dozen categories in a spreadsheet that I can screenshot when there are enough entries or changes to make it worthwhile.

[Jonny042]

Trying not to geek out too much on the fact that my latest customer is Head of Engineering at the Alpine F1 Team...

He's in the middle of a really cool 911 project, and we've had many great conversations about various topics over the past few months:

https://www.instagram.com/10til12/

[chrisbalich]

Originally Posted by Jonny042

I've been busy with a few things of late, not project or car related. In the meantime, I've been trying to make sure something is happening on the project, even if it's a little thing, every single day.

More often than not it means buying a part, or researching something when I have a few minutes to spare.

Not so long ago I had four brand new GKN CV joints sent straight from Pelican Parts to a race shop that offers CV lightening services. The results were impressive:




Not a bad start, at least. This is a small part of a larger and heavier assembly - I have found a place to make axles to my specification at a reasonable cost, so combining hollow axles, the lightened CV joints, and a few other tricks I have up my sleeve will result in a total of 10 pounds saved off the axle assemblies!

When it comes to shaving off weight, 10 pounds is a pretty big deal, so I'm happy with that.

Lightening CVs is something I’ve been wanting to do for years.
I’ve been at my job a year and haven’t quite nailed down the best way to do this myself…at least not in a way the owner will consent to.

[PeteKz]

Interesting. Did you only lighten the outer CV joint?

[LukasM]

Originally Posted by Jonny042

In the hierarchy of where you want to lose weight, it could be worse! At least half unsprung, a tiny bit rotating, and at the rear, so not bad!

At the absolute top of the hierarchy is anything rotating at crankshaft speed, I know that the crank and rods (lightweight Pauter) I am using are a full 6 pounds lighter than the 3.0SC parts in PHM. Also, I've rounded up clutch and flywheel components that are 4.5 pounds lighter than the Aluminum Sachs pressure plate and RSR style billet flywheel in PHM! So there's another 10+ pounds that I've identified in the best possible place.

I am using Project Heavy Metal as my benchmark, 100%. I pretty much know, or can find out, what every single part weighs on that car, so it gives me a means to quantify my progress as I go. That car was 2200lbs, (999kg!).

I do need to figure out a way to present it as a running total in the thread somehow. Probably just a half dozen categories in a spreadsheet that I can screenshot when there are enough entries or changes to make it worthwhile.

You really are not leaving any stone unturned Jonny, I would never even have considered CV joints a thing to look at, or trunk hinge bolts and bushings for that matter!

Are you following Jonas from Islandworks on Youtube? He is doing an amazing 964 race car build, lots of composites, 3D printed parts etc. and also kept "adding up" the weight savings after each episode.

Do you already know what you are going to do intake wise? The plastic 964 plenum (or one of the carbon fiber aftermarket options e.g. from Island Works or Silverlake e) together with a single drive by wire throttle body will save you a bunch of weight compared to your old MFI setup.

[AG81]

WOW.

Extremely impressive.

I am just now learning the nuances of a light long hood. It was something for Ed Mayo to say..."I think I can peel out in this thing"

[Jonny042]

Originally Posted by chrisbalich

Lightening CVs is something I’ve been wanting to do for years.
I’ve been at my job a year and haven’t quite nailed down the best way to do this myself…at least not in a way the owner will consent to.

For the cost of having it done I didn't even consider doing it myself. Once the outer diameter is machined (the only thing done to remove weight) the outer race shrinks a small amount and the grooves need to be re-honed to allow the balls to fit and the CV to run freely.

The next step is to see if I can successfully do the honing process myself to allow me to use 3/4" (19.05mm) balls instead of the 19mm standard ones.

"Why", you may ask?



The 24 balls for the 4 CV joints weigh over 1-1/2 pounds. A lighter option does exist... but they only come in 3/4" (19.05mm)

[Jonny042]

Originally Posted by AG81

WOW.

Extremely impressive.

I am just now learning the nuances of a light long hood. It was something for Ed Mayo to say..."I think I can peel out in this thing"

It's incredible, isn't it?!

[Jonny042]

Originally Posted by LukasM

Are you following Jonas from Islandworks on Youtube? He is doing an amazing 964 race car build, lots of composites, 3D printed parts etc. and also kept "adding up" the weight savings after each episode.

Do you already know what you are going to do intake wise? The plastic 964 plenum (or one of the carbon fiber aftermarket options e.g. from Island Works or Silverlake e) together with a single drive by wire throttle body will save you a bunch of weight compared to your old MFI setup.

I am following him, I stumbled across his channel when I came up with the idea of using "Carbon Copy" and searched the phrase "Carbon Copy 911" to see if it was previously used. It was, as a matter of fact, by Jonas, but thankfully only as a title of a video, not a whole project. But credit where credit is due, and massive respect to him for the parts he's making, truly impressive!



The video was very influential as a matter of fact! I was unimpressed with the options available for roof skins at the time and decided to make my own mold. Nothing entirely wrong with using a very thin lightweight skin with only 2 or 3 layers in a race car like his, but I want my parts to feel as stiff, or stiffer, than the factory parts they replace and refuse to compromise on stiffness and durability in search of lightness.

Now that I've got the sunroof blanking panel prototyped, fit, and available for sale, I can finally cut out the rest of the roof and build the first carbon prototype!

I have two versions of this pic. One serious:



One a little less so:

[Jonny042]

Originally Posted by PeteKz

Interesting. Did you only lighten the outer CV joint?

Yes. Note that the modern version of the CV boot flange that Caps the CV joint does not have the thick steel plate with the gasket relief, and is much lighter. So contributes greatly to the lightness of the assembly.

Joint only:





Boot only:

[Jonny042]

Originally Posted by LukasM

Do you already know what you are going to do intake wise? The plastic 964 plenum (or one of the carbon fiber aftermarket options e.g. from Island Works or Silverlake e) together with a single drive by wire throttle body will save you a bunch of weight compared to your old MFI setup.

Sorry, I forgot to address this.

From an intake perspective, you really aren't going to find anything lighter than the magnesium throttle bodies and plastic stacks that were used on the last project!

The 2.4 style throttles have a limit (41mm) to how much they can be bored, so I have a set of 2.2 throttles (boreable to 43mm) and the accompanying magnesium stacks which I will also taper bore to suit.

There is also the possibility of 3D printing carbon fiber reinforced plastic stacks which could be more easily controlled from a wall thickness perspective, and save a bit of weight over the magnesium. I'm going with Carbon Fiber or amber fiberglass rain shield style air cleaners for the classic look.

The real weight problem is with the MFI pump itself... I should know the weight of one off-hand but I think it's 12 or 13 pounds. That'll be replaced by an ECU firing 6 injectors mounted in the same location as the MFI injectors.

The ECU weighs 390g. It will also fire 6 passive coil on plug coils that weigh 100g each, and eliminate the heavy stock coil, the CDI (also heavy!) the distributor, and the plug wires. If memory serves me correctly the complete stock ignition system is nearly 10 pounds.

So that's huge... 20 pounds off the motor, in addition to the 25 pounds of weight saved by various magnesium bits and the case. 5 or 6 pounds of steel fasteners replaced by titanium, 10 pounds off the crank and rods...

That's 60 pounds off the long block and intake system without getting into the lighter alternator, carbon tins, shroud, etc. A full factory style exhaust is 50 or 60 pounds, of which I plan to save 30...

I won't go on. But it will at least 100 pounds off the motor, hopefully more. So that will allow me to lighten the motor mounting components, with that cycle of lighter car needing lighter parts driving the weight down even further as I go!

[Ian Comerford]

Make sure you add the Brise axial starter motor to your list, it's tiny and a jewel. Seen on Singer engines.

[proffighter]

Originally Posted by Jonny042

I've been busy with a few things of late, not project or car related. In the meantime, I've been trying to make sure something is happening on the project, even if it's a little thing, every single day.

More often than not it means buying a part, or researching something when I have a few minutes to spare.

Not so long ago I had four brand new GKN CV joints sent straight from Pelican Parts to a race shop that offers CV lightening services. The results were impressive:




Not a bad start, at least. This is a small part of a larger and heavier assembly - I have found a place to make axles to my specification at a reasonable cost, so combining hollow axles, the lightened CV joints, and a few other tricks I have up my sleeve will result in a total of 10 pounds saved off the axle assemblies!

When it comes to shaving off weight, 10 pounds is a pretty big deal, so I'm happy with that.

I did this 14years ago...

[Jonny042]

Originally Posted by Ian Comerford

Make sure you add the Brise axial starter motor to your list, it's tiny and a jewel. Seen on Singer engines.

It's in my basket... LOL.



Having trouble justifiying the Brise at 2.5kg and 622GBP vs. the Powerlite RAC808 at 2.6kg and 426GBP:



I was truly disappointed in the "lightweight" starter I purchased for the last project. It worked perfectly well, but it was advertised at 8 pounds but hit the scales closer to 10.

Either the Brise or the Powerlite will be another 3 or 4 pounds saved off the already light benchmark!

[Jonny042]

Originally Posted by proffighter

I did this 14years ago...

Nice! Looks like you've got billet CV boot flanges as well. I was pleased to find the newer style boots don't need the thick heavy flange.

You can buy lightened 108mm 930 CVs off the shelf from any number of vendors, but not so with the 100mm version.

[shoooo32]

CV ball weight? No stone left unturned on this build!

We've been using Pegasus lightweight CV joints on the Sports 2000s forever and they're machined by a little outfit in IL. It would be interesting to see if they'd do a run of 100mm (and/or 108mm) for Porsche guys and sell them through Pelican.

[Jonny042]

Originally Posted by shoooo32

CV ball weight? No stone left unturned on this build!

We've been using Pegasus lightweight CV joints on the Sports 2000s forever and they're machined by a little outfit in IL. It would be interesting to see if they'd do a run of 100mm (and/or 108mm) for Porsche guys and sell them through Pelican.

I did an apprenticeship program at Jim Russel Racing School in Quebec about a million years ago, so have done a bit of wrenching on F1600 and F2000's. More importantly, this is the primary reason I frequently visit the Pegasus Racing website (in the past it was thumbing through the catalog!).

That is where I learned of Two Dogg Inc. who is obviously who you are referring to!

Friendly service, good turnaround, and no BS. It was $100.00 each CV for the lightening. I asked if there'd be a discount if I had a large volume done but the difference would only be $10 or so... so not really worth pursuing beyond an individual basis IMO.

The Si3N4 balls will hopefully be 1/4 to 1/3 the weight of the steel balls. This does seem to be a bit of a secret - anyone likely crazy and/or desperate enough to do this to save a few ounces probably keeps it to themselves!!!

I do have it on good authority that they work incredibly well...