2 litre twin spark

[vwgillybilly]

Perhaps, but lots of research has lead me to believe a decent motor can't be obtained for much less than 10k.

10 years is a long time ago! I used to build fruity VW motors for 1k that long ago! The exchange rate doesn't help, especially with the fact a lot of the best parts are stateside.

Gill

[Winston Teague]

Well done Gill, now a deal has been done can you give us a good breakdown of the tech details of the motor please? My interest is in what can be done within the confines of a 356 crankcase/engine bay. I'm not in the slightest bit interested in the values/costs/prices etc.
W

[simon james]

Yes, well done Aaron for having the balls to Pull the trigger on the deal.
I’m sure we’ll all get to hear about your exploits!!!!!

[neilbardsley]

Well done Gill, now a deal has been done can you give us a good breakdown of the tech details of the motor please? My interest is in what can be done within the confines of a 356 crankcase/engine bay. I'm not in the slightest bit interested in the values/costs/prices etc.
W

Winston have a look at John's web site they offer a kit to do this. Im pretty sure they have the spec of the can, pistons and cylinders. They Also have a very good dyno compare of different setups. Of course this engine may not be one of John's kits but you will get an idea

https://youtu.be/BpU3jvVMyZQ

Sent from my X5pro using Tapatalk

[john ruston]

Always thought it comical that someone can ask for full mechanical details without paying and then say there not interested in values costs etc.
I have three of these type of engines and would have happily have bought this one as they improve the cars if you are into that type of thing and stops the ware on original engine.

[vwgillybilly]

[quote="john ruston"]Always thought it comical that someone can ask for full mechanical details without paying and then say there not interested in values costs etc.

Could you elaborate here please John?

Thanks

Gill

[vwgillybilly]

Thanks Simon & Winston.

I'll divulge the full info on build etc once I've gone through all the receipts.

Basic overview of spec is...

Scat billet steel crank
Carrillo rods
Shasta barells & pistons (90mm)
Neutek SX2 cam
Cromoly push rods
Solex P1140 carbs
Twin spark converted 1958 heads
Ceramic coated header
Bosch twin spark ignition
Built in a good 1958 case
Full flow oiling
Completely turnkey.


Blown a massive chunk of the budget on this but it made sense as I needed a complete motor. I found my last A fairly average to drive with its super motor, so hopefully this will pep it up. The focus of his build is to create a driver's car, not a pretty car. Though hopefully it should be visually appealing too.

Gill

[Winston Teague]

John, i kinda get what you mean, but there are also plenty of engine people selling parts with big claims attached to them in terms of performance improvements, and also plenty of people who market and others who buy with seemingly little more that 'Buy this it'll be brilliant' here's the bill and no detail.

Gill, This should be a great bit of kit, as it will represent much of the experience of the one of the best in the business. I have engine envy! I fancy a big cc but otherwise simple motor for mine as its a summer months everyday smoker, and i fancy building it myself, all folly i'm sure, John but that's just how i am!

Thanks for the info, all fascinating! W

[simon james]

Aaron that’s perfect for your car! A period engine, with benefits!
Loving the idea of the barn find look but one that packs a serious punch.
I wasn’t sure how well built it was, but it sounds like it has all the right ingredients to be a reliable bruiser.

[neilbardsley]

John, i kinda get what you mean, but there are also plenty of engine people selling parts with big claims attached to them in terms of performance improvements, and also plenty of people who market and others who buy with seemingly little more that 'Buy this it'll be brilliant' here's the bill and no detail.

Gill, This should be a great bit of kit, as it will represent much of the experience of the one of the best in the business. I have engine envy! I fancy a big cc but otherwise simple motor for mine as its a summer months everyday smoker, and i fancy building it myself, all folly i'm sure, John but that's just how i am!

Thanks for the info, all fascinating! W

Winston I enjoy window shopping too. Here is the Willhoit article I was talking about.

"Since we had already digitized all of the cams listed on the attached chart, it was easy to plug them
into the software and see the results. I had used the Elgin 7008 camshaft many times and had been
happy with the results. This was my cam of choice for any customer who wanted a “hotter” cam, but
since the flow tests showed a consistent increase in flow as lift was increased, I decided to depart
from the usual 356 cams and try something new. I selected a VW type 1 profile that had 240 degrees
of duration at .050” (close to the Elgin 7008) but instead of .333” of lift it had .385” which would give a
net of .500” vs. the 7008s net lift of .433”. Now, since the later VW cam is mounted lower in the case
and doesn’t have the rod clearance problems that a 356 has, a much larger base circle can be used
on the VW cam lobe which makes a short duration/high lift cam easily possible. It’s still possible on a
356 but the base circle must be ground smaller so that the rods clear the cam lobes. Grinding the
base circle smaller makes the lobe smaller which increases the wear. To help with this problem, I
had .020” holes EDM machined into the face of the lifters which would provide direct oiling to the cam
lobes (this same modification has been used on all the future high lift cams). Special higher rate dual
valve springs were used to accommodate the higher lift with lightweight aluminum retainers. The new
cam was ground and then digitized and plugged into the program. The results were just what I
wanted, better overall torque and hp with no change in the rpm at which the torque and hp were
made. "

http://www.willhoitautorestoration.com/ ... v-2010.pdf

[john ruston]

There is no one specific solution to building these engines.
We now know best way of selling a unit!
Each of the people who do the building do it in varying ways.I have been involved in paying for five varying units over the years.
I am not certain that a twin spark is needed.
Certainly we have both types and the conventional system seems to work well with up to 200 bhp.
Bottom line is it’s makes the cars better fun to drive if that’s what you want.
We started the idea about fourteen years ago when I thought using a four cam 2 litre twin cam engine in my Carrera 2 GT was stupid with potential costs involved.Even put one in my 904 to do a regularity rally.
The engines had the same power or slightly more than four cam but unfortunately not same sound.
They are only toys!

[smallspeed]

Spark plugs are interesting in these engines - I've been reading a lot recently on type 4 heads, and seems like moving spark plugs to the Porsche 914 location is worth about 10bhp in a mild-ish type 4 build vs. the standard vw plug location.
I get what a twin spark is for, but with modern plugs/leads/timing/fuel solutions I wonder if its actually very beneficial vs. one correctly located plug?

All very interesting stuff, and nothing will beat the kudos of a "double-dizzy" and all those leads, just wonder if its a case of diminishing returns vs an optimised single plug solution?

Would love to see some pics of this engine at some point (and the polo one replacing it) - I bet they look cracking

[Winston Teague]

That Willhoit article is really interesting, thanks Neil. W

[neilbardsley]

I thought I would post this from the 912 registry (and there are similar findings on the 356 registry) too.

Don't put air screens on your velocity stacks they cost power. Putting a screen directly over the velocity stacks interrupts the air flow. See below

http://www.912bbs.org/vb/showthread.php ... fler/page2

"For those that care, here are videos from the dyno runs with both the Supersound and the GDP/Concept 1 mufflers.

https://m.youtube.com/watch?v=34mojvV_5vs

https://m.youtube.com/watch?v=St8_OFZaOhE

Interestingly enough, adding the air cleaners did not change horsepower. Putting screens on the velocity stacks cost 15 hp!"