Overhead Cams
 

How much money/time would be required to make some SOHC or DOHC heads for a beetle. Everything else has been done already. I know porsche made some quad cam 4 cylinders in the 1960's but one of those engines will set you back 90K. :eek: Either belt driven off the crank pully or modify the case and crank gears for a timing chain. Maybe use some subaru cams since the engine share the same basic design. This was just a thought that I've had for years bouncing around in my head. What do you guys think.?????


Call me crazy but I have a dream. :)

The name "Russ Fellows" comes to mind ... Porsche heads to T4 Engine ... NOW THAT is "Aircooled Technology" :agree:

http://www.johnmaherracing.co.uk/int...y99jan2000.htm

Sandeep

:righton:

Thats awesome.

Now that I know its been done I want one even more. :)

:raiseroof

Its been done with an authentic tuning part (heads) made many years ago by Ludwig Apfelbeck. Two inlet valves, one exhaust valve, twin spark plugs.

I took a picture of one of the remaining heads (they are one head per cylinder) and it is in the gallery. That head hasn't had all the machine work done to it BTW, but you get the picture.

A project with those heads is in the making, but it will take at least one or two years before it will be completed...

Greetings,
Walter

Lets see if I can post a pic of one of Roberto's heads on the flow bench here.

http://www.keversite.com/fotoalbum/f...2004100213.jpg

Walter

Ohc
 

Sorry its only eye candy :rolleyes: :D
http://www.centralvwaudi.com/develop...sorts5_008.jpg http://www.centralvwaudi.com/develop...sorts5_017.jpg
due to be stripped down for inspection this week hopefully, so I'll give you an update on how its held up.

Just for the record
104mm barrels 944 pistons ceramic coated crowns, inlet and exhaust ports.
Currently puts out 350bhp, has done at least 10k miles this year.
runs 11.2 on slicks 11.4 on treads 120ish terminal
heads havent leaked at all this year.Running 12lbs of boost and 6.sumthin':1 comp ratio,i.e. the most we could get,as we're not running domed pistons.
stock crank not c/w, stock rods and runs 3 camshafts :laugh:

The only recurring fault this season is broken rockers after burnouts,(seems the rev limiter isn't quick enough to catch up. :laugh: (set at 7500 rpm)

Due to be painted polar silver and rewired, with the k,jet in the bin and replaced with Motec full engine management and also running an intake plenum.

I want it...


How well does the engine fit into your car. How wide is it, approx... :) :confused:

Just a smidge wider than t4, mods required on the back panel edges to clear the cam pulleys

Better Pics
 

Do you have any that are larger?

I am not looking to copy it, just want a better idea of what you did.

D

look here
 

http://www.centralvwaudi.com/new_page_1.htm

http://www.centralvwaudi.com/Russ_Fellows.htm

any other questions feel free to ask.

Paul

Hi,
How was Russ's experience with the deep sump? Any plans for dry sump or is it just not needed with a deep wet sump?
Thanks,
Walter

no probs with oil supply at all .it also makes it easier to connect returns from heads ,so it looks like its here to stay.

Nice work. The machine shop hours had to have been staggering.

D

Not really, the thinking time was the greatest.
Once the ideas are planned out the machining was the easy bit.
I suppose that when I think of machine shop ,I think of lathes and millers and stuff. So that was a very small part .
The welding took the most time I guess. Still it turned out cheaper than going to Pauter heads and probably more reliable too.
After all It doesn't really have any non stock parts.
The cams are cut and pegged 911
The pistons are stock 944
The rods are stock 2.0 as is the crank


No you're right the machining that went into it are ,indeed staggering
I just hadn't added it all up.

This season it will have custom pistons, full engine managment, bigger turbo, redesigned inlet manifold and it'll look a lot prettier :laugh:
Well at least for a week or so. :laugh:

How do you get away with all that engine and using a non c/w crank shaft? I would have thought it would be one of the first things you did. Damn cool though I remember the magazine feature on it.

Speaking on OHC type 4 engines, has anybody ever heard of the 'Overfly' engine that Rolf Holzapfel developed for the Kaefer Cup?
Alex maybe?


It was a new development in 1995 from Holzapfel in which he also used the Porsche 964 cylinder heads AND the 100mm cylinders and pistons. He also used those with a 86mm stroke SCAT crank to give exactly 2,7 ltr.
He used a cam housing that his tuning workshop made themselves.
The test engine with 10,4 compression and self developed Melcher cams produced 247 (DIN) hp at 6250 rpm and 294 Nm at 5500 rpm! The engine used twin spark (from the dual spark 964 heads) and 51mm Weber carbs.

Personally I don't understand how you can use the stock 100mm cylinders which ran with 76,4 mm stroke in the 964 engine for 86mm stroke, but the picture in the german mag 'Gute Fahrt' showed all these parts indeed together!

Unfortunately these never did make it into the Kaefer Cup due to the 2 liter restriction the following year(s).

As you would supect, everything has been done already by some one.

Greetings,
Walter

During the design stage we came across that article from Gute Fahrt.
I got the impression that Dr Gerolds car was powered by "that" type of engine ,By "that" I mean cast cam boxes( that was the bit that nearly made us give up!)
For the amount of machining, it was much more economical to do the job the way we did.
We also noticed that they cut out the barrel registers and welded in new peices to change the stud spacing.We just redrilled the heads and cambox to accommodate the difference.
Its funny seeing all the different 911 headed motors and we all seem to use the same belt setup.

Crank......Seems that too many people throw away too many stock parts to replace them with parts of an inferior quality.

Bobtail,

Very nice work. Do you think any of you would be willing to share drawings of what you welded or machined so we could build something on this side of the pond? I can weld and machine in house, so in my spare time I could probably build one up in oh say four years.... It would be interesting to do it piece by piece as one had time and money for parts. It also would help to learn from the mistakes ya'll (from Texas) made. So whip up some plans and sell them to me.

Thanks,

Randy

Drawings? :laugh: you realise we write with a tig torch :laugh:

Really its quite simple to work out what goes where and what needs modding, No, honestly Ive been trying since we got it running to convince folks its doable for not very much cost.

We kept the stud spacing as T4 and modded the heads and camboxes.
The head oil returns go into the deep sump.

You're lucky in that you can get the bits together and mail me, we didn't have that luxury. :bawling:

The crank drive was machined to adapt the T4 taper which went to 2 polo crank sprockets, just a simple top hat design.
We had to buy the bits and make them fit together ,not knowing it would work.

Just go buy your carrera 2 twin plug heads and 2 cam boxes, with cams and take some measurements.
Ill always be here for advice. :D

Writing with the big blue arc, I understand. I have been writing with plasma as I can use a smaller font, and use the blue arc to edit. Let me work up some courage (and cash) and then start looking for the heads and bits.

And I will be asking lots of questions.

Thanks,
Randy

Cool!, but how would you use the cams of the Carrera? I mean you cant just saw of the remaining cylinder at each end: a six cylinder has a very different cam timing. You would be out by 30 degrees or something...?
Did you have new cams made (for a 4-cylinder)??

On another note of OHC aircooled engines: did all of you know that the Citroen GSA had a 4-cylinder OHC aircooled engine? It was only 1300 cc, but still, it has been made in quite some numbers (at least in Europe) in the late seventies/ early eighties(?).
I should have got one from the salvage yard then
alter
Greetings,
W

Oh yes you cut the 2 middle lobes out of the cam and I think you turn it ...I cant remember but you turn the 2 parts so many degrees and pin the parts together, to make a 4 cyl cam.
We did have Piper make some cams but they seemed not as good as the pinned stock cams.

Ok, but to pin two parts of a cut cam back together must be a very special procedure I'am sure!
Imagine you don't exactly know what you are doing and the cam halves come loose :bawling:
Would love to see the two cam halves apart and the pins showing. Did you perhaps make a picture of the cam halves as well?

Thanks already for the insight in your mods!

Walter

I will see if the cams are out at the moment and I will take pics.....

To be honest I haven't seen them yet myself. :o

Even the pace of developement on this true street Beetle legend is mind blowing :agree:

Is Russ's oil pump 3rd cam lobeless? Is that even a word yet?

Best of luck to the Pro Champ and team. All in one piece for the Easter T'ball this w/end?

VT20 for the fastest Beetle? Short notice no problem, Warrington. (I'll keep wishing!) I'd pay the £35 to see this even closer ;)

Matt

Nope I think its still a turbo grind!....what a waste.

Nope....www.centralvwaudi.com/protoruss.htm

? Not quite with you Matt.....Pink slip?.............You'd win at the moment :laugh:

'Love the new colour, looks 'as nails! Looking forward to seeing it for real..

Cheers for the pics.

Yeah, new blue slips with the VOSA logo, your local 'ish' friendly MOT station... :)

Matt

Thanks for the update of the cool pics!
It slowly starts to grow on me how it all works...sort of....

Greetings,
Walter

A very old topic, I know, but I just ran into this and I couldn't find a link to it via the search so figured I'd post it here
https://boxerville.se/forum/viewtopic.php?id=45026