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danster

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john vanlandingham
'Arf? 'ow 'arf?

Aluminium.

Clever Trevor.

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John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

While the search for a lighter gudgeon pin goes on. I was thinking about the cylinder head.
So the weight question comes into play again here. I was looking at the components used and found it interesting to see that VW used the same valve springs on many different engines types. This means the valve weights can vary drastically between engines yet they used the same valve springs.
This made me wonder if the valve weight and tappet weight actually has a great effect on the chosen spring, or the rate of spring is more linked to the cam profile or other factors.
It looks like I can significantly reduce the valve train weight if I use parts from the later engines. 7mm stems instead of 8mm, lighter spring retainer and collets, lighter tappet compared to the oil filled hydro type.
I had a search around but most of the valve spring rate stuff seems to be based on huge V8 engines rather than small 8V engines.
As the engine will be revved high I wish to avoid valve float, but at the same time don't want to use massive springs more suited to a coilover!

I see "Beehive" type springs are beginning to find their way onto many production engines now, so they could they be an option.

Anyone got any thoughts on this?

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Disappointingly not yet a Jackass

Quote
danster
While the search for a lighter gudgeon pin goes on. I was thinking about the cylinder head.
So the weight question comes into play again here. I was looking at the components used and found it interesting to see that VW used the same valve springs on many different engines types. This means the valve weights can vary drastically between engines yet they used the same valve springs.
This made me wonder if the valve weight and tappet weight actually has a great effect on the chosen spring, or the rate of spring is more linked to the cam profile or other factors.
It looks like I can significantly reduce the valve train weight if I use parts from the later engines. 7mm stems instead of 8mm, lighter spring retainer and collets, lighter tappet compared to the oil filled hydro type.
I had a search around but most of the valve spring rate stuff seems to be based on huge V8 engines rather than small 8V engines.
As the engine will be revved high I wish to avoid valve float, but at the same time don't want to use massive springs more suited to a coilover!

I see "Beehive" type springs are beginning to find their way onto many production engines now, so they could they be an option.

Anyone got any thoughts on this?

Yeah me t'oughts are as usual you're t'inkin's good.
(How do you write when you don't ever say "th" but say it somewhere between a D and a Ulter T...like 'tanks'---you're welcome)

Search "Billzilla" ---http://www.billzilla.org/4agmods.htm
an Oztralian pilot who really thinks things thru and documents everything well.. And while he's looking at Toiletta 4AGE, it's detailed enough you can ponder the ideas and apply to other poxy little motors like we screw wif.
He noted that the springs for a bazillion rpm 4AGE thing only need to make maybe 39 pounds seat pressure...

and you're also right that it ain't just weight but profiles, although in the last 10 oer so years the people making really nasty n.a. cams have woken up to not pounding guides to death and work on the opening ramps better than 20-30 years ago.

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John Vanlandingham
Sleezattle, WA, USA

Vive le Prole-le-ralliat

www.rallyrace.net/jvab
CALL +1 206 431-9696
Remember! Pacific Standard Time
is 3 hours behind Eastern Standard Time.

That link was a good read. Plenty of sensible sounding stuff in there.
Oh, tanks for dat if that is what you mean John?

Going to dig the scales out and complete some more component weighing tomorrow, nearly bedtime here and I can't be bothered getting a load of oil dripping from a hydro tappet all over me at the moment.

Found a few oem beehive spring options we get over here to check out and see if there is potential with them.

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Disappointingly not yet a Jackass

Jeepers, is that the time. It's taken 5 months to track down gudgeon pins!! At this rate of progress any potential increase in the performance from the engine will be negated by my failing reaction times and physical degeneration due to old age.

Anyway, check out the pins...


The keen eyed may notice that the pins I finally found were 4mm longer than what I need. However I felt far happier reducing the length of the longer lighter wall thickness pins rather than trying to bore the original heavy ones.

So here are the finished pins. There's 5 of them in the line up but who can spot the fat imposter?

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Disappointingly not yet a Jackass

Quote
danster
There's 5 of them in the line up but who can spot the fat imposter?

Can't believe so many punters do the lottery but there were no takers here........It was free entry during these recession times, but as nobody answered no 2 I will just have to drink all the beer I had set aside for the winner myself.

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Disappointingly not yet a Jackass