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Discussion Starter #1
Paul Spruell has agreed to help with my stroker engine (Piston and rod design-rods to be 2mm longer instead of shorter-more torque baby!) and has advised me that there was someone in Australia that made 90mm bore liners. Does anyone know where I might be able to find this gentleman??
 

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DDoug, I suspect Paul was referring to a company called Beninca. They make a monoliner, although I didn't realize it allowed them to get the bore to 90mm. That's a really big hole. If I'm not mistaken the monoliner (including piston oil squirters is nearly $5,000).

Erik
 

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Discussion Starter #3
DDoug, I suspect Paul was referring to a company called Beninca. They make a monoliner, although I didn't realize it allowed them to get the bore to 90mm. That's a really big hole. If I'm not mistaken the monoliner (including piston oil squirters is nearly $5,000).

Erik
He didn't say and couldn't remember a name, other than "someone in Australia makes a 90mm liner that would help get the displacement you're looking for". As for the crank, yes, found a machine shop who will lighten it, stroke it, balance it and re-nitride it. The rod ends need to be clearanced for the extra stroke I'm looking for and to run 17psi of boost, the pistons can be flat toped-to dished-if need be. But the numbers add up, just need to know where I can locate these 90mm bore liners.
 

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For special cylinder liners, I'd recommend Westwood in the UK. They handle bore sizes up to 5.300" and have no minimum order - that enough for you?!

I'll follow this thread with interest ....

Alex.
 

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Discussion Starter #9
For special cylinder liners, I'd recommend Westwood in the UK. They handle bore sizes up to 5.300" and have no minimum order - that enough for you?!

I'll follow this thread with interest ....

Alex.
Thanks for that link, the monoliners did not get up to 90mm.
 

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Thanks for that link, the monoliners did not get up to 90mm.
This is weird - my turbo Alfetta had OS liners (not as big as 90mm!) and forgies to suit (Arias) when I bought it. It has been causing me no end of grief trying to get/bore OS liners and end up with something strong enough/something that would stay round and sealed, so I eventually ditched the pistons and went with std bore low comp JEs from Paul Spruell (and a set of original Autodelta turbo liners which - dare I admit it - I had the cooper ring retaining protrusion machined off). Paul was out of ideas for OS liners and was very doubtful about trying to get them to work under boost especially. I can't see how you could go to 90mm - offset bores maybe? Serious headwork too? This is all very scary stuff - hope you have very deep pockets!

Very interesting idea/serious bit of engineering - will be very interested in what you come up with!
 

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when i use to live in altanta - i loved going to paul spruell when he had his alfa dealership. i guess the race car business is much more profitable for him then the repair side.
 

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An interesting thread, leading to a few basic comments:

1. Have you ever seen an Alfa 4 cylinder engine disassmbled?
2. The difference between 84 mm (stock) and 90 mm is .236 in. Assuming you had 90 mm liners fabricated, how do you propose to fit these into the block, to accomodate the existing crankshaft rod bearing spacing, and to provide sufficient space for the O-ring seals ?

Paul Spruell has agreed to help with my stroker engine (Piston and rod design-rods to be 2mm longer instead of shorter-more torque baby!) and has advised me that there was someone in Australia that made 90mm bore liners. Does anyone know where I might be able to find this gentleman??
 

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Discussion Starter #13
An interesting thread, leading to a few basic comments:

1. Have you ever seen an Alfa 4 cylinder engine disassmbled?
2. The difference between 84 mm (stock) and 90 mm is .236 in. Assuming you had 90 mm liners fabricated, how do you propose to fit these into the block, to accomodate the existing crankshaft rod bearing spacing, and to provide sufficient space for the O-ring seals ?
I have help from Alfa friends to get this sorted out, if nothing else, will remain stock LENGTH rods and stroke even further to get to the 2.5L status. Yes it does seem an old VW flat four was easier to stroke and bore out, even though it's liners were air cooled instead, but machining the block to handle big liners could be done blind folded. Again, I'll have to rely on someone with this proven experience before any wallet depleting things are done.
 

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Discussion Starter #14
when i use to live in altanta - i loved going to paul spruell when he had his alfa dealership. i guess the race car business is much more profitable for him then the repair side.
Does it have to with profit or passion? When I was thinking/pondering the possibilities of opening up a spider speed shop, the first best advice was to start off small and slowly build up other's confindence in my experience for working on these mysterious cars. I don't like OEM type of repairs either, my passion is for high end racing.
 

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Discussion Starter #15
Now, I'm drooling!!!! A 3.545:1 rear end and 75% clutch lock!!!!! That would be awesome with 500bhp! New Page 2 My top speed would be.....NICE!
 

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I have to agree with conedriver I think the pistons will be touching. the stock liners have to have flats on them so they will fit next to each other and there is a thinspot there.
and you want to add boost too. it seems the the bore to bore will be very very close. the mono well help but you still need some space. you can not have the pistons overlaping each other.
lets see if that can be worked out you will run in to the next problem of the head lifting under boost.
a 'O' ring will help and I guess replace the studs with arp. might need to also tie the mains together with some sort of a plate. might see what Jim Steck's Bonneville Alfa has done they had to deal with a lot of this and there is a lot of good info there. he was in the 400bhp range.
 

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Discussion Starter #17
I have to agree with conedriver I think the pistons will be touching. the stock liners have to have flats on them so they will fit next to each other and there is a thinspot there.
and you want to add boost too. it seems the the bore to bore will be very very close. the mono well help but you still need some space. you can not have the pistons overlaping each other.
lets see if that can be worked out you will run in to the next problem of the head lifting under boost.
a 'O' ring will help and I guess replace the studs with arp. might need to also tie the mains together with some sort of a plate. might see what Jim Steck's Bonneville Alfa has done they had to deal with a lot of this and there is a lot of good info there. he was in the 400bhp range.
Piston wall with monoliners at 90mm, as pointed out, leave just 0.118" (3mm). As far as ARP studs:
 

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DDouglas

Look up Jim Steck of Auto Componenti in Ohio. He has made monosleeves AND turbo'd a few Alfa 4's. He and Besic Motorsports did a joint venture on a 2.ol turbo twinspark that was running 20+ pounds boost and made 550hp at the rear wheels for their Bonneville Salt flats land speed record holding spider.
I would think a few more pounds of boost would give you more torque cheaper and faster than the R&D needed to make/source custom sleeves, rods, crank and pistons.
 

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DDouglas

Look up Jim Steck of Auto Componenti in Ohio. He has made monosleeves AND turbo'd a few Alfa 4's. He and Besic Motorsports did a joint venture on a 2.ol turbo twinspark that was running 20+ pounds boost and made 550hp at the rear wheels for their Bonneville Salt flats land speed record holding spider.
I would think a few more pounds of boost would give you more torque cheaper and faster than the R&D needed to make/source custom sleeves, rods, crank and pistons.
It is all relative though. 15 psi would increase baseline hp by 100%, the more baseline you can build, the more boosted baseline you get. I've become very, very aware of fellow Ohioan Jim Steck.
 

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Andy is corect about cost and time. Jim told me that he machined the aluminum monosleeve on his NC milling machine, and the process took a week. This is before he inserted the steel cylinder sleeves. There's also the issue of computer modelling the design to create the NC tool path for the monosleeve and engine block. Just imagine the cost of this if it was farmed out to a traditional machine shop.

Or, consider moving the individual cylinders sideways. This is how the 1275 cc engines for Sprites & Minis are enlarged to near 1500cc. The dimension between cylinders won't accomodate larger bores, so #1 is bored to the left, #2 is bored to the right, etc. (of course, this is on a cast iron block).

DDouglas

Look up Jim Steck of Auto Componenti in Ohio. He has made monosleeves AND turbo'd a few Alfa 4's. He and Besic Motorsports did a joint venture on a 2.ol turbo twinspark that was running 20+ pounds boost and made 550hp at the rear wheels for their Bonneville Salt flats land speed record holding spider.
I would think a few more pounds of boost would give you more torque cheaper and faster than the R&D needed to make/source custom sleeves, rods, crank and pistons.
 
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