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Discussion Starter #1
I have just had a crank made for a flat 8 using two in-line/joined-together 'Sud boxer engine blocks.
The idea is to do a home grown version of the Australian Gioccattolo mid-V8 of the '80's but using Alfa components as much as possible to retain the Alfa genes. A flat 12 engine as per the BB Ferrari of the 1980's would have been good but Peter Brady my crankshaft designing expert tells me this is fraught with flexing issues over the length of three 'Sud engine blocks. I believe him: hence the flat 8 idea.
There are a number of issues to be sorted with the engine then later the body mods of the Sprint of course.
Once the engine is together and bench tested we will look at the body and your experience with the mid engine 6C setup of the Sprint body is very interesting and may be a useful guide.

Vin
 

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WOW!
What an awesome project you have there :D

Are you redesigning the camshaft/heads as well?
As in - 1 long camshaft or keeping them separate?

Good luck with it all :)
 

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If this doesn't go down as 1 of the most amazing Alfa based engine builds, then I don't know what would! :D

BTW, that's a h3ll of an introductory post :cool::cool::cool:
 

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Top marks for total creativity and the balls to actually go all the way and have a go at this! I once read an article about a chap who built a flat 12 engine with two porsche 911 blocks to make a 917 recreation - in Canberra I believe. I gave some thought to joining alfa boxer engines together too after reading this, but nothing further than that!

Seriously, please keep us updated on this project as this is a significant engineering challenge. Would be nice to see the car in action at the next Canberra Auto Italia festival!

~Benjamin (South Aus as well)
 

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Great Project. Funny thing is that we had a conversation here last month about the same thing and if it was possible and we concluded that it could be done but the cost and finding someone to do it was the problem.


I am glad that someone is crazy enough to decide to do such a wild thing.
 

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Discussion Starter #10
After raving on to anyone who would listen, especially our son, all of them thinking I was nuts I decided it was about time I stopped the BS and actually did something about the flat8. A flat 12 would have been even better but the risk of the crank failing was obviously much greater. So a flat8 it will be.
The crankshaft was cast last week, the pics show the pattern designed from which it was cast.We beefed up the journals where it really counts and they measure close- within a mm or2-of the 2 and a half inch journals you will find on many Aussie/US V8's of bigger engine capacity than the flat8.
To give the long crank a chance to rev reliably (it weighs 39kg out of the mould) we stuck with the 1500 stroke but are going with the 1700 pistons which will make for 3.2L.
With the bench test we will keep it simple- fairly standard heads and carbs- 36 IDF's and sort out any glitches first eg cam couplings, cooling and oil feed before going for a bit more go.
I have a spare Holden Camira= Vauxhall/GM ECU's and EFI wiring loom from a previous project '81 Sud EFI conversion so we can wire this in for the ignition and reprogram to suit.

Will it work? We'll see!

cheers
V
 

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Cool! I remember reading about a chap who made a straight 8 using 2 Nord blocks for his 8C replica.
Appreciate your thought on keeping the Alfa genes.
 

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The exhaust note from this will be awesome. On the order of a grand prix engine I would imagine. What are you upgrading in the rod and pistons besides an overbore to 1700? Estimate horsepower?
 

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Presumably with the 90 degree crank in the flat 8, it will have the same effective configuration as a flat plane crank in a 90 degree V8? And that combination is awesome!!
Will you be using 8V heads - and possibly 16V later??
 

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wowsers

Respect! im a engineer turner miller,nice work. will you be builing a totally new sump as some rigidity could be found in that area. very cool:eek:
 

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Wow nice project.
I was thinking about that kind of thing some time ago. But i would do it the easy way. I would join two engines together wia some sort of flange so that they would be screwed together one fro the flywheel side another from the pulley side. Both of them would be mounted on a steel frame and then the frame would mount into the rear of my 33 with a gearbox from an audi.

Will read with interest!
 

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The crankshaft does seem to be a lot longer than in "Normal" V8 engines as the bores are quite separate and not uniformly spaced. Keeping the stroke to 1500 spec will keep the crank journals more "overlapped" and hence a stiffer crank so hopefully the length will not create problems??
 

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Discussion Starter #19
I guess if a straight 8 will hold together then this one is in with a chance!

The gearbox: as Lloyd's 300HP supercharged racer on slicks works well with the Sud box we will stick with this.

The rods and bolts will be lightened and balanced to keep it as smooth as possible, along with the crankshaft of course. We don't think external harmonic balancers will be needed to achieve this.

Crank design: the shorter stroke is good as there's about 12mm/ half an inch of overlap of the crank journals, at least as good as some local V8's.

The exhaust note note should be BETTER than a flat plane V8!

At this stage I think a supercharger would an easier way to get more power than going to 16 valve heads, as we are using larger valves from later engines and will clean up the flow on the heads.

Rigidity: this is the killer so there will be the 8mm steel plate acting as a girdle bracing the blocks together via the sump faces. Along with longer bolts to suit it will have dowels where we can fit them, and tags at 90 degrees so the crossbolts for the main bearing caps that pass through the block will bolt down through them.

Power: ultimately 300+ shouldn't be too hard but we want to make sure it works first before getting too carried away.
 
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