Strangest Ported British Anzani Block Ever!

[John (Taylor) Gabrowski]

Melting down further a fire melted down Anzani powerhead "blob" produced / extricated this weird 6 in cylinder ported 322cc cast iron loop engine class B Alky block. What were they thinking that produced this is unknown way of porting is unknown? There is also a class A Alky block done the same way in one cylinder only and both A and B engine blocks show the bores were actively worn from operational use. What horsepower and rpm this produced I know of no record that exists. Anyone want to give it a try as to what they were trying to do or did here?

See other posts on the A & B British Anzani threads to see more and different pictures of this strangely ported Anzani engine block.

[twister]

Those are the holes for the coreplugs in the water jacket - I wonder if they were trying to cool the aluminum (sorry, aluminium - it's British!) stuffers/flow directors in order to cool the incoming charge?

Bit risky, though, allowing water effectively into the transfer ports...

[John (Taylor) Gabrowski]

Good question on that one. I also have an class A block that is the same way and it was run quite a bit too as was the B and there are no signs of the engine having any difficulty running with those ports as the bores show normal wear and good clearances too. Jim Hallum had heard something about Tenney experimenting with the number of ports but never seen any blocks. Jim was into making all the ports, carb side, trasnfer intake and exhaust way bigger and those engines went like blazes for them out there in the North Western USA region.

[John (Taylor) Gabrowski]

Rod: Where the new ports were machined / tunnelled through and went into the water jacket there are liner type tubes installed to prevent water from going into the intakes / crankcase passages. That made for a huge increase in the crankcase volume to create the extra two cylinder side transfer ports that are directly under the exhaust port(s). To compensate for that increase crankcase volume one of Tenney's engineers indicated that they increased the amount of nitromethane to around 40% that also registered with a large increase in horsepower too as part of the scheme to the new porting.

One of the board readers, Jerry Coombs whose father who also raced Anzani had his Anzani B engine converted this way but didn't increase the nitro in the fuel mix so the engine actually performed worse than it did before the work was done. The result was moot but what leaves me scratching my head was the abscence of the instructions to increase the nitromethane unless Bill Tenney assumed that a racer would increase on nitro content with regard for the increase in porting as he got used to the new changes to the engine. That also seems plausable on Bill Tenney's part that a racer would experiment with his rig too anyway so that assumption fits.

[twister]

This is all interesting stuff! I have no experience of running anything other than pump gasoline fuel, but you guys would be interested to see the porting in my record-holding 250 block...no photos I'm afraid.

This is an aluminium block, factory prepared, and bored for the 344 motor, then sleeved back to 52mm for 250cc. The sleeves are solid at the top, so the spark plugs are screwed into the sleeves. Ports are everywhere!

There is no vertical line available for ring gaps to pass clear of ports, so the pistons were modded to single ring, pegged over the smallest ports; the piston skirt windows had to be closed off partly so these didn't expose other porting.

It goes like stink on gasoline after I changed the Konig carb for a Lectron, but the pistons are so worn it's a pig to fire up and it has to be down on power...any offers of 52mm pistons would be welcomed!

If I've done it right, there should be a photo attached, showing Jim Garrick (of Anzani, who built the motor originally) and me just after the record run in 2000. The exhaust is missing, it's a single Konig pipe. Unfortunately, Jim is no longer with us. He was so chuffed when we got the record with his antique motor...

It'll run again some day!

[John (Taylor) Gabrowski]

After seeing the story on that 250CC of yours and the need of 2 single ring 52 millimeter pistons are needed to continue this engines onslaught at records I will soon enough go into the pistons box for Anzani As and see if I can come up with the beasts for pistons you need. Its sleeved aluminum block is very similar to what Kay Harrison produced at HRP as the back bone engine blocks for the Harrison racing outboards. Go to the Harrison thread on this BRF site and see them for yourself. Ironically the Harrison A and B blocks I have here are fitted to Anzani crankcases to use Anzani components as the base for everything else. Eventually Harrison became completely Harrison as it evolved away from using Anzani components.

[twister]

After seeing the story on that 250CC of yours and the need of 2 single ring 52 millimeter pistons are needed to continue this engines onslaught at records I will soon enough go into the pistons box for Anzani As and see if I can come up with the beasts for pistons you need. Its sleeved aluminum block is very similar to what Kay Harrison produced at HRP as the back bone engine blocks for the Harrison racing outboards. Go to the Harrison thread on this BRF site and see them for yourself. Ironically the Harrison A and B blocks I have here are fitted to Anzani crankcases to use Anzani components as the base for everything else. Eventually Harrison became completely Harrison as it evolved away from using Anzani components.
If any spare pistons come to light, it'd be just great. They don't have to be single-ring, the old ones just have the bottom rings left out.

Also, if I could find any 62mm pistons (that's the UK B Class, 344cc, and not the US B, which were 60mm) I guess I'd have enough parts to build up another complete motor.

[John (Taylor) Gabrowski]

I might have single ring A pistons but for sure I have 2 ring (2 square rings) and even 3 ring (2 square & 1 Dykes ring) versions too. The only question is of size, stock bore or oversize at this point. I think we are in luck from what I can remember of what is in the box as there are both new and good used versions there.

In terms of the B-Stock size of pistons, I know I have 2 but they are allocated to a stock block I am already working with. I also sent 1 new pistons to another restorer in the USA so it might be a stretch to find anymore of those here. I am going to contact another restorer in the USA to see if he acquired any B Stock pistons in some of the parts he recently acquired that are in used condition and may be surplus. He too is eager to see this Anzani restoration movement expand with more engines restored where ever.

[twister]

The single rings are in fact Dykes (bear in mind it's several years since I've been inside this motor, but it's coming back to me!) It's on stock bore at present, but oversize would be no problem, we'd bore to suit.

The B/62mm pistons don't have to be perfect, just runnable - we're not talking about racing these things (not just yet, anyway)

[twister]

When I was searching seriously for the Anzani pistons, probably 10 years ago, a local supplier suggested contacting Hepworth, who made the originals. Armed with the skirt numbers, we called Hepworth, and had a strange response. At first, it seemed like the guy was saying he had some on the shelf, or at least could make some, but then he clammed up, saying that these pistons 'were never released to the aftermarket' - those were his very words.

We wondered if this meant that there was originally some kind of deal that the pistons would only be supplied through the Anzani company, and that Hepworth were bound by this to this day? It all sounded very strange.

[John (Taylor) Gabrowski]

Harrison Racing Products who produced the Harrison racing outboards had made by Lodite, finished and sold the Lodite pistons for use in Harrison racing Outboards and the Anzanis both. The HRP Lodite piston product were of a superior quality of casting and manufacture than the original Anzani product made by their subcontractors in the UK. What I am saying is that I have both makers of the pistons here in quantity giving a greater variety in what is available in either the UK or American product. Not a bad situation to be in! :)