Stavros

I know they far from ideal, but spacer plates...

Who can make them? Or is it a simple job for any machine shop if you give em a head gasket as a template?
What would they charge you think?

And how do you work out how thick you need? My sums suck at the best of times

BigErn

http://www.ferriday.co.uk/

Martin-Hadland

iTrader: (2)

It's easy to work out as long as you have data for the engine in question... pm me what you have and want to achieve and will work it out for you.

Garage19

Bout Ł120 for a ferriday one.

Put up the details of the engine and wha cr you want it to finish up and i'll work it ou for you.

GARETH T

steve you thicko,, it isnt the hardest thing to work out

Stavros

Never ever underestimate my thickness when it comes to maths

Early high comp B200E volvo lump.

10.1@1 compression.

88.9mm bore, 80mm stroke.

More like 8:1 (possibly a bit less) is more like what id want.

Martin-Hadland

iTrader: (2)

A spacer of 2.25mm will give you 8.2:1 comp ratio... 2.5mm will give about 8.0:1

Your engine has a swept bore size of 496.57cc which needs 54.5cc above the piston at tdc (unswept) to give 10.11:1C/R . Add 496.57 to 54.5 = 551.07cc then divide this by the 54.5 which gives your c/r. Each 1mm extra thickness gives an aditional 6.2cc... Clear as mud?

GARETH T

just to help you out steve for future referance

first you need to calculate the non swept volume/chamber volume


cylinder volume (boreXstroke)
-------------------------------------------chamber volume
compression ratio minus 1



now you can work out your displacment ratio,,,,

cylinder volume
--------------------------------=displacment ratio
combustion chamber

the displacemnt ratio is always one more than its compression ratio

thickness of spacer would equal

new disp.ratio - old disp. ratio
----------------------------------------------------X stroke = thickness of plate
new disp.ratio X old disp. ratio

Stavros

ah see, sums, they jus confuse me, lol.

seriously tho, cheers guys

question from the ferriday site, it says...

so the head gasket- between spacer n block, or spacer n head? im guessing block to spacer as its iron-alloy rather than alloy-alloy.

personally im suprised you dont need 2 gaskets

richm

fit the gasket between the parts with the biggest differential of thermal expansion - eg. if you have iron block, steel spacer and aluminium head, then fit the gasket between the spacer and the head. Headgaskets are designed to accomodate the expansion movement of the dissimilar materials.
Make sure the mating faces that don't have the gasket are as flat and clean as possible to ensure an intimate face to face surface fit - the sealant effectively then seals the fluid channels, the effect of the sealant round the cylinders is largely academic.

Stavros

Surely your better off fitting a gasket either side, no?

Or is it truly safe enough?

richm

fitting a gasket both sides of the plate will almost certainly lead to trouble, there's too much compressible material and it will allow the potential for the plate to move around too much.
It is common practice to fit a shim plate to a skimmed head, the thickness is much less but principle is the same, only one gasket and sealant the other side.
If the mating faces are flat and clean enough, there is nowhere for the cylinder pressure to go in practice, the plate behaves like an extension of the block or head.

Stavros

Cool, so head gasket between spacer and alloy head, just sealant between spacer and iron block?

Gotcha.

I think

GARETH T

why dont you just rip the pistons out and machine a little off them?

Martin-Hadland

iTrader: (2)

I doubt the pistons will stand the amount needed to be removed, could take some out of the head too though.

Chip

iTrader: (3)

Just get johnsons to make you up a 3-4mm head gasket, will only cost about the same as people are talking about here for a spacer anyway!

Stavros

Whooooo?

http://www.google.co.uk/search?hl=en&q=johnsons&meta=

Chip

iTrader: (3)

Johnsons gaskets, they are in bradford.

You send them a head gasket, they copy it in the thickness you want, they make either copper or copper kevlar ones.

Quick turn around normally too

Chip

iTrader: (3)

PS


quick google search came up with these details:

G. R. Johnson Gaskets
2 Verity Street, East Bierly, Bradford, Yorkshire, BD4 6PN, UK Map
Tel: +44 (0) 1274 682298



I dont have their number with me to check its the same company, but im pretty confident it is.

Stavros

You sure thats the place Chip?

Ill be ringing Bradford so I dont want to end up ringing the wrong person and it get all "Yeah ill hook you up maayyed, give me your credit card details and ill do it mint maayyed" and then all my money dissapears