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Wed Sep 12, 2012 10:31 pm

It's been a while... how are things going?

Thu Sep 13, 2012 10:45 pm

The good news is... The project is now getting some priority.

Last week, I brought the lower end to Rocky Jennings. He will be installing his proprietary camshaft, balanced/rebuilt connecting rods, and blueprinted oil pump. Due to the requirement of special tooling for setting up his camshaft, I'm having him build the lower end.

In addition to this, he will be honing and setting up the clearance for the cylinders to accept the higher heat expansion with boost.

No new pictures for right now, but it's nice to say the project is back on it's feet.

Scott

Wed Oct 17, 2012 7:53 pm

Here's some pictures of the lower end build. Rocky Jennings does some very impressive work.

Wed Oct 17, 2012 8:03 pm

What's your definition of mild boost? How many lbs. Of boost are planning/hoping for?

Hans

Wed Oct 17, 2012 8:44 pm

Hi Hans

Previous people have had good success running 10lbs or less. My goal is 8-10lbs.

Scott

Thu Oct 18, 2012 7:19 am

Not sure if you have found a tuner yet for the mega squirt but Brendon at
Ralley tuned is in Washington and was a great help to me with my stand alone engine management.

Thu Oct 18, 2012 7:47 am

I'm eagerly awaiting more updates.

Thu Oct 18, 2012 8:01 am

I am surprised the crank isn't counter weighted, or is that not a common practice on water boxer engines?

A friend is building a type4 engine right now with a counter weighted crank, 101 Pistons and jugs with 6 studs-2 extra studs from the heads to the jugs so they don't ever come loose.

Paul

Thu Oct 18, 2012 8:44 am

I've been really curious about this for some time. Back when I was building hopped up type 1 engines, we always used forged counterweighted cranks, but there seems to be a consensus here that believes that it isn't necessary with the WBX. Seems "counter" intuitive

Thu Oct 18, 2012 9:23 am

Counterweighting counteracts deflection of the crank at high rpms. There are two reasons the WBX doesn't need them. First of all, the crank itself is very stout. If you look at the material between the journals it is massive. Secondly, it isn't a high rpm engine, so it doesn't operate at revs that would require counterweights.

If you were to turn the wbx into a high rpm engine, it would be good to counterweight the crank. Also, when the stroke of the crank is increased by welding and offset grinding, counterweighting becomes necessary because the deflection forces become greater.

Counterweighting a wbx crank is straightforward. Jose at DPR does them all the time, but in a stock stroke standard rpm wbx it just isn't necessary.

David

Thu Oct 18, 2012 9:46 am

I can't say for sure, but I've been led to believe that type 1 counterweights were just welded on to standard 69mm forged VW cranks and machined down, without touching the rod journals. If that's the case, why would a WBX crank need to be stroked? It seems like a turbo engine could benefit from a higher RPM operating range anyway. Also, non-counterweighted cranks just plain look funny, but that's entirely subjective.

Thu Oct 18, 2012 1:38 pm

Mario at the dub shop is your man in Washington for tuning a boosted vw with megasquirt.

Thu Oct 18, 2012 8:24 pm

Zeitgeist 13 wrote: I can't say for sure, but I've been led to believe that type 1 counterweights were just welded on to standard 69mm forged VW cranks and machined down, without touching the rod journals. If that's the case, why would a WBX crank need to be stroked? It seems like a turbo engine could benefit from a higher RPM operating range anyway. Also, non-counterweighted cranks just plain look funny, but that's entirely subjective.

Stock 1600 cranks can be counterweighted that way, but most people just buy one of the aftermarket forged chromoly cranks when building up an air cooled motor these days. But with WBX cranks, the method you describe is definitely how they do it. Jose at DPR Machine Shop is one of the main sources of modified WBX cranks. He has built a couple for me. They are definitely a work of art.

I wouldn't do a stroked crank for a turbo WBX, but it does make sense to use one for a normally aspirated motor to go above 2.2 liters. Non-counterweighted WBX cranks may look unbalanced and awkward, but in use they work very well. When I overhauled the DJ motor I was running in my van for a while, I used a counterweighted stock stroke crank. It didn't feel any different than a standard crank WBX.

D

D

Mon Nov 26, 2012 1:00 am

Updates?

Sun Dec 02, 2012 11:52 pm

Progress Update.

I've gotten the lower end back from Rocky Jennings. Inside this beauty is his proprietary camshaft, upgraded/balanced connecting rods, and I also had the cylinders slightly oversized to compensate for additional heat with added boost.

As I was building this setup, I was deadset on turbocharging this engine, however, plans have changed a little bit. This will now be a supercharged engine. I will be using a SC12 supercharger that was used on late 80's early 90's Toyota MR2's. The great thing about this supercharger is it has it's own oil sump, reasonably small, was setup for 8lbs of boost, and incorporates an electric clutch, where you can activate the supercharger when you need it. I'm not certain if I will use the clutch setup as of yet. It all depends on how creative I can get with a bypass system.

After way to many hours of research, I decided to go out and purchase one. I will be pulling it apart for inspection, re-sealing, and fresh oil.

Supercharging isn't as efficient as a turbo unit, however, there is no turbo lag, it's easier to calculate and adjust boost, and will relieve the complication of modifying the exhaust.

In the lower left of the picture, you will see the SC12 supercharger. Hopefully I didn't crush anyone's dreams by switching to a supercharger....

Mon Dec 03, 2012 1:21 am

Well I for one am very excited about your switch to supercharger. I was very close to going down the sc12/14 path before switching to a high comp na 2.4 setup. I was going to fit it in lieu of the a/c compressor. Although the clutch set up is cool my personal opinon is best to run it full time. Less complexity and easier to tune. I am sure this engine will have a really good torque curve for a bus. Does Rocky's cam have not much overlap/wide lsa so it is good for boost? Excited. Greg

Mon Dec 03, 2012 8:32 am

:shock: :popcorn: :vw: :ts: =D> :D :popcorn: :vw: :van_blue: :van_blue: :van_blue: :van_blue:

Mon Dec 03, 2012 9:57 am

It would be cool if you can figure out a way to convert the engine to a serpentine belt system for all the peripherals

Mon Dec 03, 2012 10:35 am

I would prefer a turbo install over a SC. The exhaust and oil system modification necessary for a turbo would be on par with the belt drive modification for SC, the WBX is torquey enough on the low end that turbo lag wouldn't bother me any and recovering waste heat to generate the boost makes more sense to me than robbing crank power.

Mon Dec 03, 2012 10:39 am

Perhaps a compound setup, with the SC to provide boost off idle up to around 1.5k, and then switch over to turbo beyond that. Complicated design, but fun to build--no?