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I have collected all that I can so far for an Oxy engine.

The indutry needs to grow a little in my opinion before I can complete my engine the way I want it.

1. Nickies 95mm (Porsche size and with Porsche rings) in a drop in T5 head stud size. This can be done actually, just special order. Probably similar to what Tom Notch has had done.

2. Heads. I want to find a streetable T5 spacing set of heads. No race only Scat or Autocraft stuff. Legend has it that it has been done for stock VW heads with some machining.

Tom Notch wrote: The new pent roofs make this conversion for me obsolete and really not worth the hassle. 8 years ago many things were not available that are available now, like alloy pent roof cases (have you seen one yet, Joe? they are a nice piece).

Tom,
I'am sure you have heard all the extra machine work that has to be done one one of the new brazilian alu type 1 cases, so I don't think cost-wise, its an alternative.
However, its not an alternative quality wise either: the case shines nicely, but I doubt the sand casting is up to par with the original VW pressure casting.
From an engineering standpoint the brazilian alu case seems to be unneccessary thick in area's it doesn't need to be, just to make casting simpler I suppose. Therefore I think they are even noticebly heavier. At least it really felt like that when I had one in my hands.

Oh, and does it holds about 5 ltr oil standard? or has the spin-on oil filter standard?

And I always like it to adjust good quality stock parts, but thats just my thing.

Greetings,
Walter

What is the OD of the wasser exhaust guides?

Would the European Motor works T4 8mm id exhaust guides help?

What exactly are the issues with the wasser head re valves?

And Tom, e-mail me if that block is for sale, etc.

So, do you guys think you could relocate the head studs to type4 spacing? I know it leaves you with ordinary heads, but with Paul Cooper's (bobtail) type IV - 911 head conversion, some 106.3 nickies you would have the bore and strength of a type IV, hemi spherical SOHC twin plug heads and the ability to run HUGE cranks!!
What do you all think? We looking at a super motor here, or what?
Did'nt someone mention a Berg 95mm crank somewhere? So... Whats that, 95 x 106.3 is.... D'OH! Forgot the maths to get displacement, again
Ofcourse you'd have all sorts of hassles with rod lengths, deckheight, engine width, etc, etc, etc... But still. It's so much more fun just knowing it can be done! So can it?

Cam wrote: So... Whats that, 95 x 106.3 is.... D'OH! Forgot the maths to get displacement, again

Hello,

Around 3371 cc! Nice

Cheers,
Richard

The cylinder spacing / Crankshaft Throws are TypeI

You cannot run Type IV Heads....

Besides, why not just build a Type IV?

The whole point of Running an Oxyboxer is to get away from the Type IV...

No need for heads that drops valve-seats, expensive fan-shrouds that aren't correctly / completely engineered, over-priced exuast... The list goes on.

Oh-Ya, did I mention Heavy motor with sluggish performance?

Build an Oxyboxer, and expect Type I performance W/ Type IV longevity...

People just don't understand the reason for building this conversion I guess...

- Joe

I had 3 thoughts relating to this, although one probably would only apply to T4s.

1)The wasser bore centers are the same as T1... 108mm IIRC. T4 is 112mm.
The maximum bore size without playing silly buggers with the bore spacing would be ~103 IF the jugs were thin wall and just about touched--- 101.6 is probably about the limit, and that doesn't leave much air/fins in between the jugs. One could still get OK cooling if you kept it water cooled IMHO. (The above does not account for stud spacing)

2)It looks relatively easy to weld up the bottom holes on a wasser head, and use them with AC cylinders, and a small radiator. I would like to know what the issues/mods required to get wasser heads up to a decent performance level, using "normal" valves etc.

3)The following is a half baked idea. This may be stupid... But I've seen in in cut aways of aircraft engines... It also brings to mind the 911 jugs I saw here... almost no cylinder projection above the top fin...

The #1 issue with big bore jugs on a T4 (103-105) is the heads dont have enough meat to stay flat at the sealing surface.

Figure out where the top ring stops.
Cut the jug ~1mm (.040") up from there. This will be the new sealing surface. This is (usually) ~5mm down.
Step cut the head for the 103s AWAY from the std sealing surface by the same amount you cut off. The center std part gets bored for the PISTON crown with a tad of clearance... In other words, the head becomes the top of the bore that does not see the rings.

The net result is you end up with ~4-5mm of extra aluminum in the head in the direction that provides sealing surface stiffness, and ~5mm less "uncooled" cylinder in the head, the sealing surface is closer to the top fin etc. The "effective" combustion chamber is all in the head.(including the first 5mm of bore--end result would be jut about flush with the stock casting/machined area surface)

You might actually have to trim the bottom of the jug...
Can't remember the T4 cylinder>head projection, and I'm late for work...

Might be effective on T1s in a blown app for better cooling/more rigitity.

(from 85.5 openings>94s)


Flame suit on...

Joe, thats what I said. The type IV's have crap heads so it would'nt be worth it unless you do what bobtail did and adapt 911 heads.

Wally, was it you who was looking at putting 964 cylinders and pistons on a WBX? If so I think this will be the way I'll go. Keep the strong internals, blueprint and balance everything, block off the lifter holes, run a blank cam to drive the oil pump, which will be dry sump btw. I do heaps of circuit racing and hillclimbs, so coupled with the factory deep sump, it should all be sweet
Then run 964 C&P's with late 930 heads and re-pinned camshafts. Oh! And forced induction, probably supercharged

Piledriver wrote:1)The wasser bore centers are the same as T1... 108mm IIRC. T4 is 112mm.
Flame suit on...

Hello,

Don't want to flame and I don't know the wbx bore centers, but, T1 borecenter is 112mm and T4 is 124,5mm.

Cheers,
Richard

Thanks, I couldn't quite remember, and didnt google it... The T5 is the same as T1.

The point still stands, there isnt much cooling going on between the jugs or underneath/in the middle, limiting the pracical size on the T1/T5 block in a street driven air cooled app, assuming the stud/head part was just an engineering problem.

Any thought on the step cut? Might only work on 1700 heads---

Piledriver wrote: Any thought on the step cut? Might only work on 1700 heads---

Hello,

Well, I'm not sure if there is enough meat in the heads to do this, but it's just the thing Porsche did with the 993 twin-turbo. By doing this they were able to keep the combustionpressure away from the joint between the cilinder and the head.
Maybe a groove the same i.d. and o.d. as the cilinder, say 1mm deep, into the head would be sufficient? You'll have to adjust your deckheight with some shims though. But that doesn't need to be a bad thing , getting it as thight as possible. I think this could apply both T1 and T4.

Cheers,
Richard

I was also thinking this would be a method to effectively make the somewhat stroke limited 911 jugs "longer", and _ease_ the shimming required for strokers in general... The extra space from the step-cut WOULD be a cylinder spacer of sorts.

Well, the 964 'jugs' have a stock stroke of 76,4mm, giving you exact 2400 cc (with 100mm bore). If you want more, go type 4
They do are short though, but it seems Porsche just lets the pistonskirt exit the bottom of the jug quite a bit in their stock application and does so with a very short rod (124mm: stock 66mm type 4 stroke rod!)
If it works for Porsche...

Greetings,
Walter

Wally wrote:

Tom Notch wrote: The new pent roofs make this conversion for me obsolete and really not worth the hassle. 8 years ago many things were not available that are available now, like alloy pent roof cases (have you seen one yet, Joe? they are a nice piece).

Tom,
I'am sure you have heard all the extra machine work that has to be done one one of the new brazilian alu type 1 cases, so I don't think cost-wise, its an alternative.
However, its not an alternative quality wise either: the case shines nicely, but I doubt the sand casting is up to par with the original VW pressure casting.
From an engineering standpoint the brazilian alu case seems to be unneccessary thick in area's it doesn't need to be, just to make casting simpler I suppose. Therefore I think they are even noticebly heavier. At least it really felt like that when I had one in my hands.

Oh, and does it holds about 5 ltr oil standard? or has the spin-on oil filter standard?

And I always like it to adjust good quality stock parts, but thats just my thing.

Greetings,
Walter

Not to highjack this thread but I have a motor going together with one of the new pent roof cases distributed by Bugpack. They are VERY different that the stock replacement aluminum cases. The casting is MUCH improved and they come already machined in a variety of different ways. The weight is 45 pounds (yes heavy).
These cases are VERY nice and inexpensive.

My $.02. Go back to arguing.