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4valve heads


richard100t

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:luigi: How many people would buy an aftermarket 4 valve head kit with all the other parts that would need to go with it, for a 120 rwhp v11? How much I wonder would we be willing to pay for that kind of performance? Lets say it was $5000 usd Who would go for it?
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:luigi: How many people would buy an aftermarket 4 valve head kit with all the other parts that would need to go with it, for a 120 rwhp v11? How much I wonder would we be willing to pay for that kind of performance? Lets say it was $5000 usd Who would go for it?

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Too bad Jim Fueling died: he was able to produce pushrod 4-valve heads for the Sposta, so I doubt he'd have had much trouble adapting the design for a Goose. IIRC, the Sposta heads ran to about $2000, installed. That's certainly sustainable for someone who's looking for a serious performance upgrade to the V11 motor, since it's real stumbling block is breathing. At $1000/head, it's certainly justifiable, given that just porting the 2-valve heads to get them to breath as well as an assembled 4v casting should do runs to a significant percentage of that price. At $5000? That price/performance figure is harder to justify; essentially, you're looking at the far side of the Laffer curve there; by achieving a lower price, the number of units sold will more than offset the lower profits/unit.

 

While it would be nice if the factory could figure out how to make the Hi-Cam motor again, I can't say that doing so is their only hope for the future: making reliable 4-valve push-rod heads that can just be slapped onto the current engine design will buy them time to do research into a water-cooled engine, while rejuvenating the existing model line by making the old air-cooled mill more comparable to competing models in the all-important hp spec. And if this was a factory solution, owners of current V11 models could shell out the ducats to retrofit with no compunctions about warrantee issues, vendor sustainability, etc.

 

Keep talking, I'm all ears!

:luigi:

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Too bad Jim Fueling died: he was able to produce pushrod 4-valve heads for the Sposta, so I doubt he'd have had much trouble adapting the design for a Goose. IIRC, the Sposta heads ran to about $2000, installed. That's certainly sustainable for someone who's looking for a serious performance upgrade to the V11 motor, since it's real stumbling block is breathing. At $1000/head, it's certainly justifiable, given that just porting the 2-valve heads to get them to breath as well as an assembled 4v casting should do runs to a significant percentage of that price. At $5000? That price/performance figure is harder to justify; essentially, you're looking at the far side of the Laffer curve there; by achieving a lower price, the number of units sold will more than offset the lower profits/unit.

 

While it would be nice if the factory could figure out how to make the Hi-Cam motor again, I can't say that doing so is their only hope for the future: making reliable 4-valve push-rod heads that can just be slapped onto the current engine design will buy them time to do research into a water-cooled engine, while rejuvenating the existing model line by making the old air-cooled mill more comparable to competing models in the all-important hp spec. And if this was a factory solution, owners of current V11 models could shell out the ducats to retrofit with no compunctions about warrantee issues, vendor sustainability, etc.

 

Keep talking, I'm all ears!

:luigi:

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I would love to see 4 valve heads on the market for $1000 a piece! I'm not a mechanic, but dont you have to get a new cam to go with them plus you know lol that while its apart your going to wanna drop in higher compression pistons etc. I can see it getting near $5k real fast

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I would love to see 4 valve heads on the market for $1000 a piece! I'm not a mechanic, but dont you have to get a new cam to go with them plus you know lol that while its apart your going to wanna drop in higher compression pistons etc. I can see it getting near $5k real fast

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Well, in an ideal world Guzzi would have upgraded the stock machines to roller lifters a long time ago! But if you want to stay w/ solid lifters, why would you need a new cam? We're not talking about producing a Hi-Cam repro, just some 4v pushrod heads. To do this, the rocker arms wind up looking pretty much like the ones in the Hi-Cam motor, but the pushrods just go all the way down to the existing cam location for the V11 motor. Yes, you're not going to end up with a 135hp fire-breather running at 10k rpms like the tuned & tweaked Hi-Cams, but a solid 100hp a/c motor running at the existing 8k red-line ain't nothin to sneeze at, and should be doable within the design limits of an upgraded V11 like we're talking about.

 

But you're right about what the final cost to get there is likely to be; I was just considering the actual pricing for 4v heads as assembled units, not incidentals that most purchasers would want to consider intalling at the same time such as roller cam & lifters, Ti pushrods, the required new headers, new pistons, etc. In "all at once" fashion, yes, this would easily push $5K, and would be what's required to get to that reliable 100hp output. The beauty is, it's something that could be "pieced" together as finances permit, if the parts were out there...

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Guest Brian Robson

I've got a stack of old magazines and reading a comparison of a 4V Sport and a plain 1100 Sport with a 2 valve head, there was a few mph difference in speed and torque was the same.

In the search for more ???? wouldn't a cheaper and more effective option be lighter wheels and better suspension?

Is there such a thing as reliable 100hp V11 output?

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Sounds like high 80's hp is the most you can reasonably get from these motors without spending big money. Thats fine with me, a duc is a duc, & a Goose is a Goose lol If speed was all I wanted I couldve gotten the Hayabusa for about the same or less money.

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Well, in an ideal world Guzzi would have upgraded the stock machines to roller lifters a long time ago! But if you want to stay w/ solid lifters, why would you need a new cam? We're not talking about producing a Hi-Cam repro, just some 4v pushrod heads. To do this, the rocker arms wind up looking pretty much like the ones in the Hi-Cam motor, but the pushrods just go all the way down to the existing cam location for the V11 motor. Yes, you're not going to end up with a 135hp fire-breather running at 10k rpms like the tuned & tweaked Hi-Cams, but a solid 100hp a/c motor running at the existing 8k red-line ain't nothin to sneeze at, and should be doable within the design limits of an upgraded V11 like we're talking about.

 

But you're right about what the final cost to get there is likely to be; I was just considering the actual pricing for 4v heads as assembled units, not incidentals that most purchasers would want to consider intalling at the same time such as roller cam & lifters, Ti pushrods, the required new headers, new pistons, etc. In "all at once" fashion, yes, this would easily push $5K, and would be what's required to get to that reliable 100hp output. The beauty is, it's something that could be "pieced" together as finances permit, if the parts were out there...

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A V11 with the stock cam and 4-V heads would produce a power curve like a R1 Yamaha, very top end biased. 4-V heads normally use a shorter timing than 2-V heads.

 

While it wouldn't be cheap to make a conversation, it would be great if Guzzi developed a 4-V head for the single cam motor. If all the major parts (crank, rods, cases, etc.) except the heads were the same as they are building now it would be a lot cheaper to produce than the hi-cam engine and still probably give the bike a nice power improvement and have much more potential than the 2-V motor. As somebody said, a great way to have something new until the truly new motor shows up.

 

I doubt it will happen but such a motor in the Breva 1100 (mild tune) Grizo (not so mild) and an "MGS 02" (as much as you can get past the smog police) would make paying for a new bike seem like a better idea.

 

Lex

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With it's limited finances, I think I would rather see Guzzi try to finish their water-cooled engine. Seems like a longer-ended strategy. Not that I'm against 4V heads, but it appears that people are already working on it.

J

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I've got a stack of old magazines and reading a comparison of a 4V Sport and a plain 1100 Sport with a 2 valve head, there was a few mph difference in speed and torque  was the same.

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I read a similar test a few years back where there was a track test of an 1100 Sport against the 4 valve Daytona RS. Even though on paper the RS made more horsepower and shared the same frame and cycle parts, they were able to lap faster on the 2 valver which they put down to the nature of the power delivery plus higher profile rear tyre which helped it steer better.

 

I agree that Guzzi should be looking further ahead than the old 4 valver if they want to make a seriously competitive sports bike- in fact they have no choice due to emissions.

 

Saying that, I love Paul Minnaert's cool Daytona- my favourite Guzzi special!

 

Guy :helmet:

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I read a similar test a few years back where there was a track test of an 1100 Sport against the 4 valve Daytona RS. Even though on paper the RS made more horsepower and shared the same frame and cycle parts, they were able to lap faster on the 2 valver which they put down to the nature of the power delivery plus higher profile rear tyre which helped it steer better.

 

I agree that Guzzi should be looking further ahead than the old 4 valver if they want to make a seriously competitive sports bike- in fact they have no choice due to emissions.

 

Saying that, I love Paul Minnaert's cool Daytona- my favourite Guzzi special!

 

Guy  :helmet:

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I'll drink to that :bier: That's a fine machine.

 

Søren

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I've gotta add whats already been said but if you want 120HP get an MVagusta for the same price it'd take to put into the guzzi. then youre not only different youre now "exclusive" ooOOoo or buy an R1 call it a day. I dunno I like the guzzi the way it is but I'd love it if they came out of the 70's and made a state of the art goose.

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