The Harrison Racing Outboards - Legendary Birmingham Metal Products Alky Outboards

[John (Taylor) Gabrowski]

As British Anzani wound up making engines Harrison was already making parts for Anzani for the aftermarket, in particular replacement pistons with rings assemblies in a number of ring formats. This eventually went on to some interchangeability with exhausts elbos and lengths and tapers of alluminum exhaust stacks.

A comparisson was done with Anzani (cast iron) and Harrison (cast alluminum with ferrous sleeves) 250cc engine blocks and cast aluminum heads finding that there was total interchangeability from one manfacturer to the other and between each other. Crankcase to crankcase interchangeability has not been done due to lack of having Harrison's own custom made crankcase to compare to the Anzani crankcases at this point.

They sure were cousins from these comparissons done. How close in terms of communications were done to come this close is still only speculation.

Enjoy the pictures of these close cousins.

[John (Taylor) Gabrowski]

The cousins compared. How Harrisons took over from Anzanis, their close cousins. Harrison aftermarket parts on this limited comparisson fit Anzani very nicely and Anzani parts also fit Harrisons in this 250cc block side comparisson.

Enjoy the remainder of the pictures.

[John (Taylor) Gabrowski]

The following pictures is the beginning mockup of a largely (majority) Harrison class B - 350 Alky, a 2 carb model (large primary & smaller secondary/rotary valve feeding crankcase carb) with to the lesser some Anzani parts.

This mockup starts with a complete Harrison flywheel magneto ignition system mounted on an Anzani crankcase. Within that crankcase will sit a Harrison crankshaft assembly linked to Harrison pistons in a Harrison 350cc alluminum block topped with a Harrison head.


Enjoy the concept pictures.

[John (Taylor) Gabrowski]

Though Harrison engineered their components to fit with some Anzani assemblies the interchange enjoyed between Harrison and Anzani in the 250cc class A Alkys was not taken that far in Harrison-Anzani interchangeability with the class B models in the Anzani range of 322cc to 350cc range. Though the Harrison 350cc alluminum blocks mated perfectly to the Anzani A-B crankcases and the pistons were same source Harrison products Harrison must have seen the weakness in the Anzani head-combustion chamber unit. Anzani's stock gas and even high compression heads were fine for gas or Alky with the stock composite head gasket with the head held down with Anzani 6 head bolt standard but add nitromethane to the methanol mix and there the Anzani head gasket leaked. Anzani had to go to single sheet copper gaskets or gasketless using a specially faced head with super head to block cements to cut it with 6 head bolts. Harrison seeing this added more head bolts to in effect, circle each cylinder head with bolt down pressure. It mean't 4 more head bolts or capped studs and that sealed the problem with no head to block compression leaks as a result on Harrison Bs. Harrison Bs did use sheet copper head gaskets as well racers machined heads to go gasketless with high strength head to block glues. So ended the Harrison B interchangeability with Anzani B blockwise as neither the Anzani B head could sit on Harrison alluminum B block nor could a Harrison class B head sit on a Anzani B cast iron block.

[John (Taylor) Gabrowski]

There is no compelling evidence that Bill Tenney ever shared information on the round external exhaust exits on the newer cast iron Anzani 250cc block anywhere else nor were any of these run anywhere as the existing blocks have never been finish machined or prepared to do so. Checking with Jim Hallum found the same, he never knew of the round port Anzani 250cc blocks yet at the time it is apparent Harrison was into them with both their 250cc and 350cc blocks. It was in this information climate or lack there of, environment where Ron Anderson prepared with Roger Wendt a Harrison-Anzani-Merc-Konig hybrid whose Anzani cast iron 322cc loop block was re-configured to have the rounded exhaust exits machined in the cast iron block supported with the same aluminum cast exhaust port plugs Bill Tenney used to keep the exhaust tunnel square with the exhaust port on its way out. With that done it was no problem mounting Harrison alluminum cast combo mounting flanges with integral cast elbo and stack mounts like it was a hand in glove fit to a Harrison or you could make your own easy to fit using plate and round pipe stock.

Improvements do happen in isolation or was there some information sharing here that made the difference? By all accounts Roger Wendt's twin carb hybrid engine was an outstanding and competitive engine in the North West's B Alky class with his common elements shared with the way Anzanis and Harrison's developed and ran. I will find a picture for posting of the Wendt engine apart for restoration to demonstrate these exhaust changes from squarish to round to liken it to Harrisons in the very near future. Clearly there was an advantage to how Harrison exhausts were configured that were successful enough for at least some changes to later Anzanis to mirror its American cousins the Harrison racing engines by HRP. Most 2 stroke loop engines today have round exhaust exits to where the external tuned pipe systems attach.

[John (Taylor) Gabrowski]

The following pictures are of the hybrid Wendt 322cc class B Alky block.

From Harrison (HRP) engines the developers of this cast iron loop Anzani Block put more than just some ideas from Harrison on it. In particular they re-machined the exhaust ports from the just outside of the exhaust port at the cylinder wall to the surface of the block at the exhaust flange from squarish to completely 1.5 inch diameter round making them so Harrison like. They used Harrison alluminum cast flange and exhaust elbos that then mounted Harrison HRP alluminum belled stacks.

From Harrison examples they hogged this Anzani block's primary carb intake mounting port into the block innards itself a whopping 1.675 inches diameter making for using the largest Vacturu A0-500 sleeved thoat carbs possible for the displacement of the engine. Added to that the engine has a Tillotson HL self pumping carb of 7/8th of an inch diameter right accross from the crankshaft rotary valve opening putting total carb opening between the 2 carbs over 2.5 inches in intake diameters combined. The crankshaft is Harrison full circle minimizing crankcase CCs. Coupled to these improvements they also ported the engine out so large the current cylinder side ports are slighly more than twice their orginal size making for one very well breathing engine. It ran its makeup very fast indeed even running dead heats or winning against other leading Anzanis, 4 cylinder Konigs and Quincy Flatheads by all account. It was a very successful engine in the region.

Note: This engine has suffered block flange base cracking with repairs made very skillfully with brazing the repair on and using it exactly that way after machine work refinishing. The engine was raced with these repairs until its retirement from racing and is a testament to who repaired it so well.

Enjoy these pre-restoration pictures.

[John (Taylor) Gabrowski]

The following pictures are typical of the different pipes racers tried on Harrisons and their cousins the Anzanis in this case short and fat for constant high rpm applications. By examinations they didn't look like they were used much.

Enjoy the picture(s).

[Master Oil Racing Team]

Okay John...here you go. I never thought I had any pics of my own to add to this thread, but by luck and a sidetrip on Amazing Story part II I came across a couple of old photos of a Harrison with some unique modifications. These pics were taken in 1972 at Gravois Mills, Missouri. NOA was going down and AOF had sprung up. This was the very first AOF alky race and it was billed as the Gulf Canadian Series. A bunch of the NOA guys showed up to decide if we needed to go with AOF or APBA. These are pictures of Kay Harrison's B Hydro rigged with a stationary powerhead and a tower housing that turned.

[John (Taylor) Gabrowski]

Wayne:

Nice pictures! Its too hard to tell if there is some kind of front crankcase mounted carb(s) induction systems there too to add along with the Tillotson HR and HL carbs on the side. The Mercury CD distributor ignition coil and all is plain enough. That would cook anything into life or burn water! That pipe system sure mystifies. The whole rig sure must have had a lot of people looken and scratching their heads.

Kay Harrison, you got to come over and talk about this wild engine!

[John (Taylor) Gabrowski]

Looking real hard at the front of engine pictures there is a decernable Tillotson front crankcase feeding self pumping carburator too, put on some kind of common manifold feeding through reed valves to each crankcase half? Some Harrisons had 2 front mounted Tillotsons as posted on the early pages of this thread but on this only 1 but not 2 carbs can be seen on the front for a total of 3 carbs on this engine version?

Wild setup!