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Which means "Evil Twin". Lets see your projects where you change boring into fun or create the fun from scratch.
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 Post subject: Re: Ferrari 3408 project
PostPosted: Tue Dec 20, 2016 1:32 pm 
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Also, I just noticed that the 355 throttles I've been watching on ebay have flat bases... They bolt to "manifolds" like the purple things in the pic above. The manifolds are really what I need... once I have those I can adapt whatever throttles I want.

Edit: or I could be wrong about that.
Courtesy Ricambi:

Image


Looks like they DO bolt directly to the heads.


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 Post subject: Re: Ferrari 3408 project
PostPosted: Tue Dec 20, 2016 1:49 pm 
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This is going to be Grrrreat!


Manifolds are easy ;)

5V cams are NOT so you're limited there if you go 355/360......and for sure the 5V heads don't flow that much better than the 4V heads can......mine flow about 15% more then a stock 5V head, but you can at least match the 5V without moving valve locations and then you can have whatever cam you want which will add much more than you'll get from stock cams and ported 5v heads....I think.

not sure the on the deck heights but for sure 348 liners also fit 355/360 and rod lenght is the same going back into the 60s think so I don't think the deck is taller and if it is its not by much.


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 Post subject: Re: Ferrari 3408 project
PostPosted: Wed Dec 21, 2016 3:00 am 
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mk e wrote:
This is going to be Grrrreat!

Manifolds are easy ;)

5V cams are NOT so you're limited there if you go 355/360......and for sure the 5V heads don't flow that much better than the 4V heads can......mine flow about 15% more then a stock 5V head, but you can at least match the 5V without moving valve locations and then you can have whatever cam you want which will add much more than you'll get from stock cams and ported 5v heads....I think.

not sure the on the deck heights but for sure 348 liners also fit 355/360 and rod lenght is the same going back into the 60s think so I don't think the deck is taller and if it is its not by much.


Yours aren't exactly stock 4V heads :-P
I also recall that someone produced some round blanks when he needed custom cams, although I also recall him complaining that they were quite expensive.
Were the 12cylinder 4V heads the same as the 8 cyl 4V heads?

How far ahead of the stock 4V heads are the 5V heads? Do you know how "normal" port work (avoiding welding except by accident, using epoxy fill) affects that difference?

The throttles are straight, so porting them might not be so bad, even though the cross-section changes from round to oval.

BMW S62 throttles bend at the transition from round to oval, so they're annoying to port. However, still no excuse for Dinan to charge over $5k for a set of 8.

I totally get what you're saying about cams. I'm in the same boat with the Northstar. The only cams available are regrinds, which limits the duration I can use.

Also, the 360 headers are already a little small for a 400 HP engine, so I'd have to make new ones since the 4L would be in the neighborhood of 600 HP.

Should this move to engines now? :P


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 Post subject: Re: Ferrari 3408 project
PostPosted: Wed Dec 21, 2016 9:28 am 
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On my bench at 10" h2o the stock QV/328 heads are 92-94 cfm.
The 360 head was 138. Much larger port, too big if you ask me.

I have not flowed a 348 head, but they are the same basic casting as the qv, but bigger valves (30.4mm intake) from the factory so I'm certain they flow more. I was thinking a 32 would fit, but super performance sells 32.5 so that must be the winner......that should get you to about 140cfm (at 10") but with a much smaller port cross-section than the 5V heads have which adds a bit of hp everywhere.

The TR head is a similar but not as good design, stock it flows 92-93. It has wider valve angles, smaller than QV valves and the ports are bent more....generally not as good. A lot of the work I did was to make them more like the QV heads....I have a practice QV head if you need it.

The 5V cam issue is there is something about the middle lobe that most cam machines can't grind....never looked into exactly what.

There are a few sources for 4v cams and places like web can weld up your cores to give you whatever you want. The problem I had was the firing order of my cores didn't match the crank and they weren't comfortable making the entire lobe of weld...so billets it was.

Generally there isn't much to port on a TB...just match it to the manifold nice unless you're fitting larger throttle plates or something like that. I'm a big believes in big TBs...funny knowing how much I hate big CSA ports but you can taper the port from the TB to accelerate the air and end up with very little restriction at the TB. Mine at ducati and have a 52mm plate I think it is....they're big.


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 Post subject: Re: Ferrari 3408 project
PostPosted: Wed Dec 21, 2016 10:53 am 
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mk e wrote:
On my bench at 10" h2o the stock QV/328 heads are 92-94 cfm.
The 360 head was 138. Much larger port, too big if you ask me.

I have not flowed a 348 head, but they are the same basic casting as the qv, but bigger valves (30.4mm intake) from the factory so I'm certain they flow more. I was thinking a 32 would fit, but super performance sells 32.5 so that must be the winner......that should get you to about 140cfm (at 10") but with a much smaller port cross-section than the 5V heads have which adds a bit of hp everywhere.


Epoxy can fix a port that's too big ;-)
The Bridgeport in the background of one (maybe more) of my garage pics has a CNC conversion with power quill feed. Add a motorized rotary head with a table and dead center and it's a 4 axis contraption that can do most of a CNC port job... That's my eventual goal. Once the program is developed, it might be time efficient just to pour the whole port full of epoxy and then mill the new port out.

Of course the big question of a 5V head is "what's the discharge coefficient of the center valve?" It's (probably?) going to be less efficient (and certainly going to be different) than the side valves, but by how much? I guess Ferrari over-estimated that if they cast the port that much too big.

Appreciate the offer on the practice head. It'll be a while before I might need to take you up on that, but I assume it's already been around a while, too.

Edit: If the port's too big, I can also fix that by bolting the head down to a 4L... then the valves will be too small ;-)

mk e wrote:
The 5V cam issue is there is something about the middle lobe that most cam machines can't grind....never looked into exactly what.

There are a few sources for 4v cams and places like web can weld up your cores to give you whatever you want. The problem I had was the firing order of my cores didn't match the crank and they weren't comfortable making the entire lobe of weld...so billets it was.

Generally there isn't much to port on a TB...just match it to the manifold nice unless you're fitting larger throttle plates or something like that. I'm a big believes in big TBs...funny knowing how much I hate big CSA ports but you can taper the port from the TB to accelerate the air and end up with very little restriction at the TB. Mine at ducati and have a 52mm plate I think it is....they're big.


The port entry and taper to the throttle plate, affecting plate diameter, is what I was referring to above.

VW/Audi made 5V engines for a decade or more... I'm pretty sure there are cams available in that community. However, the V8's at least have tiny tiny 91mm bore centers, to the lobes may package better into grinding equipment than the Ferrari's slightly larger bore center.


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 Post subject: Re: Ferrari 3408 project
PostPosted: Wed Dec 21, 2016 1:56 pm 
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No epoxy within an inch of the seat is the only limit I guess.

As I said I don't know the concern with grinding 5v cams just that there was something...your needed a cnc grinder I think.

I guess I'm just not convinced the 5v heads are better than the 4v stuff and kind of believe they were mainly a way to to get good flow with short duration cams for emissions (before variable timing and direct injection solved the problem) and figured if you've got a 348 engine you might as well use it.....but its not my project and there is nothing at all wrong with your 5v plan.

If you do want to make the engine thread separate from the chassis stuff let me know and I can move it or make you a moderator so you can move it.


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 Post subject: Re: Ferrari 3408 project
PostPosted: Thu Dec 22, 2016 11:10 am 
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There is this: http://www.ebay.com/itm/300673067099

Image


Been on ebay for... a couple of years?


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 Post subject: Re: Ferrari 3408 project
PostPosted: Thu Dec 22, 2016 11:37 am 
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mk e wrote:
No epoxy within an inch of the seat is the only limit I guess.

As I said I don't know the concern with grinding 5v cams just that there was something...your needed a cnc grinder I think.

I guess I'm just not convinced the 5v heads are better than the 4v stuff and kind of believe they were mainly a way to to get good flow with short duration cams for emissions (before variable timing and direct injection solved the problem) and figured if you've got a 348 engine you might as well use it.....but its not my project and there is nothing at all wrong with your 5v plan.

If you do want to make the engine thread separate from the chassis stuff let me know and I can move it or make you a moderator so you can move it.


Manufacturers went back to 4V heads because the symmetry made it easier to design for direct injection.

GM got good flow with short duration cams using only TWO valves ;)

Was thinking about the way the curtain area grew with valve lift between 4V an 5V configurations... I'll have to play with spreadsheets and see which one gives more at low lift... subtracting interference from adjacent valves from the "simple" answer. I was also thinking that turning a valve blank or two with 0.500 margins to install in the non-flowing seats while flowing the third seat *might* sort of mimic the actual flow area of the valve in action and lead to better porting.

Do you know right off what the stock 3.6 valve sizes are? Do you know the valve positions or separations? The 5V geometry also gets pretty complex because the valves are at different angles.


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 Post subject: Re: Ferrari 3408 project
PostPosted: Thu Dec 22, 2016 1:28 pm 
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TheDarkSideOfWill wrote:

Manufacturers went back to 4V heads because the symmetry made it easier to design for direct injection.

GM got good flow with short duration cams using only TWO valves ;)


I'm pretty sure it was more about not being able to justify the cost once they could run more cam timing. It's a simple $/hp and hp/lbs calculation with OEMs most of the time.

GM did okish with 2V, but nothing very spectacular....so they added boost to the performance cars/trucks.

TheDarkSideOfWill wrote:
Was thinking about the way the curtain area grew with valve lift between 4V an 5V configurations... I'll have to play with spreadsheets and see which one gives more at low lift... subtracting interference from adjacent valves from the "simple" answer. I was also thinking that turning a valve blank or two with 0.500 margins to install in the non-flowing seats while flowing the third seat *might* sort of mimic the actual flow area of the valve in action and lead to better porting.

Do you know right off what the stock 3.6 valve sizes are? Do you know the valve positions or separations? The 5V geometry also gets pretty complex because the valves are at different angles.


I don't recall size/angle/placement info. I only played with the head because it was at my house and I wondered how it did. The engine had fire damage I think it was, Dave in South Africa bought it cheap on ebay and asked me to help him get it on a boat.....the whole engine was less than the block you found.

The 5v math gives a lot more perimeter and a little more total available area. You're right that they can interfer with eachother.....but that is true with 4V as well and is why I changed my valve spacing to go to 34mm intakes. They would fit with stock spacing but wouldn't do any better than 32mm flow wise because they were just too close to each other...even the 32mm was showing less flow than 31.5 % area wise so 32 is really it on the 3x8 casting without going crazy...but that will get you as good or better than the stock 5v heads. From memory I think ferrari left plenty of space in the 5V heads so you can probably oversize the valves a little and still be good.....maybe 160 is possible from them and that will make 70-80hp/ cylinder which would put you closer to 600 than 500....500rwhp I guess.


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 Post subject: Re: Ferrari 3408 project
PostPosted: Thu Dec 22, 2016 3:38 pm 
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Valves are here. there are 24, all all look the same.


...but Lana put me on housework while I was waiting so I need to finish cleaning the stove before heading back to the shop.


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