Stroked in the head

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Jetta2
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Re: Stroked in the head

Post by Jetta2 »

Gaining displacememt can only be done by altering the bore or stroke or both.

Doing anything with the combustion chamber will either increase or decrease the combustion chamber volume and have a bearing on the compression ratio, but not anything to do with the displacement of the motor itself.

Piston bore size and crank stroke determines displacement.

And what is a "forged head"?
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Re: Stroked in the head

Post by Howie-WP »

Kobuswiese wrote: Mon Dec 10, 2018 10:59 am Cnc machined from a block of alluminium.
:crazy: :fear: :crazy:
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Re: Stroked in the head

Post by Jetta2 »

There are many 8 valve motors out there running boost using a spacer plate or lower compression pistons, running stock internals (pistons for those running spacer plates, rods, cranks, etc) and making big power.
I think you are overthinking the whole thing.

I remember someone here in SA wanted to have a CNC machined billet head for some motor (also a 4 cylinder) and the quote was in excess of 30K just for that.

And CNC machined billet and forged are two totally different things.
You can CNC machine a forged billet of aluminium yes, but there is no such thing as a "forged head".

It would be plenty cheaper to get lower compression pistons, get ARP rod bolts, build a motor, chuck boost at it and make decent power.
Setups like that can handle 1.5Bar + of boost if tuned properly.
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Re: Stroked in the head

Post by dcmk4 »

Seems like a lot of money for what can be done with a motor that already exists..
Why overbuild something mediocre to achieve what can be done with an existing motor? IE. a 1.8t 20v?
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Re: Stroked in the head

Post by Yakuza Racer »

Kobuswiese wrote: Mon Dec 10, 2018 12:34 pm
dcmk4 wrote:Seems like a lot of money for what can be done with a motor that already exists..
Why overbuild something mediocre to achieve what can be done with an existing motor? IE. a 1.8t 20v?
"Eveybody does the same old same old."

Just exploring some new ideas. If money was no option, what would you do? I'm shure you also get some ideas you would like to try out?

This kind of stuff always gets me thinking so i'm just curious to know if it has been done before and how much could be gained on such a conversion " hypothetically speaking".

IE: the ultimate build.



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Re: Stroked in the head

Post by Yakuza Racer »

well different strokes and what what... check out B is for Build on Youtube... those mofuggers go waaaaay above normal... M5 into an old datsun pipe build.. cray stuff..
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Re: Stroked in the head

Post by PapaJo »

The ultimate build could be the ultimate build with loads of money chucked at it with cnc head or billet machined block that some overseas companies are building for drag cars. Loads of hours, research and development, lessons learned and broken motor configurations ans piles of money went into those.

There are many examples of very bulletproof builds in various configurations allover the forum abd internet and it is tried, tested and proven build configurations too.

Nothing wrong with the tinkering idea of an ultimate build, but define an ultimate build. If money is no object, anything is possible. Do they last is a different story though. Higher performance = more money = more strain and wear on components and usually shorter life span of motor.

Meeting a happy medium where you gain very good performance at a reasonable price that lasts is my ultimate motor. Best bang for a buck situation. I’ve seen and been in a situation where my lower spent money build car has outperformed a car that had loads of money thrown at it, but conversion setup didn’t work right for him.

Anything is possible depending on how deep the pockets are.

No pun intended, just giving my 2c.
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