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topcatcustom
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Post by topcatcustom »

I think it is actually just pushed on now, and the thread is there for an old fashioned puller, will try pulling it off later!

Now stripped the engine, cam actually doesn't look too bad, so may be able to use it.

Also measured the approximate stroke at 114mm, which makes the CR (according to an online calculator) 5.48:1! Displacement is 4.9l, not including the area above the piston at TDC, do you include that?!

Have been speaking to someone about having the crank crack tested, hardened etc, but to be honest I decided even if it does have a hairline crack I'll still use it, as can't get another one anyway so I may not bother?! If I start spending money on the crank, then I should also do the same on the pistons and rods, for now I think I will just leave it mainly standard and can think about an expensive rebuild in the future...

Olly I can't deck it as 1 it would need to go down 3/4" which would remove the entire deck, and 2 the spark plugs come through the sides of the cylinders, you can just about see them in the pic.


TC

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ChrisJC
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Post by ChrisJC »

Capacity is measured as swept volume.

Chris.
--
Series IIA 4.6 V8
R/R P38 4.6 V8
R/R L405 4.4 SDV8

unstable load
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Post by unstable load »

Displacement is diameter/stroke related. (Pi r squared x stroke)
C.R. is cylinder swept volume/combustion chamber related. (cylinder swept volume over chamber volume as a ratio)
You will struggle a bit with that one as the area above the piston tapers a little.
Here is a formula to calculate the conical frustrum which is the cut off cone immediately above the piston... [url]http://www.calculatorsoup.com/calculato ... rustum.php

Then, calculate the volume of the straight bit of the upper area as per the cylinder volume formula, add it to the frustrum, plus the buretted volume from the head chamber ad you will have the other part of the figures for the CR as volume at BDC over volume at TDC.
Cheers,
John

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Post by mgbv8 »

topcatcustom wrote:Measured the bore at 82.7mm today, making it 3 1/4". Also I calculated the entire area above the piston at TDC at 136cc including 1mm of head gasket. Of course this isn't much help right now as I haven't measured the stroke properly! Either way it's not going to be easy getting the CR up, those Alfa Romeo hemi pistons at 84mm could be a good start though, I'm planning on stripping the last few bits from the engine and getting the thickness of the bores/liners measured.

Has anyone seen anything like the cam sprocket ring or have any idea about how to undo it? I can't fit the cam chain unless it comes off!


http://www.jbs.co.uk/product/1545/forge ... n-kit-83mm

Perry Stephenson

MGB GT + Rover V8

9.62 @ 137.37mph

Now looking for 8 seconds with a SBC engine

http://www.youtube.com/watch?v=nVscbPHgue0&list=UUqIlXfSAoiZ--GyG4tfRrjw



https://www.youtube.com/watch?v=eg3avnsNKrc&index=2&list=FLqIlXfSAoiZ--GyG4tfRrjw

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topcatcustom
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Post by topcatcustom »

http://www.ebay.co.uk/itm/FORD-Focus-Mo ... 1215201121

These modern duratec pistons look fantastic, and look like they have Teflon coated skirts too, and can get them for only £28 each! Think my mind is made up, should be fine with just a couple of pounds boost.

Engine stripped now, going to give it a chemical and steam clean Monday, then order pistons and find some 7075 ally billet to machine some new conrods from, should be fun! Cam actually looks in very good nick so will most likely just reuse it for now.
TC

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topcatcustom
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Post by topcatcustom »

These Duratec engines are seen to make over 200bhp on stock internals reliably, with a high CR. Am I right to assume that with half the RPM, half the CR, and (200bhp/4 cylinders = 50bhp per cylinder/piston vs 200bhp/8 cylinders) my estimate of 25bhp per cylinder/piston, they should be completely reliable?

I've had a price on some 7075 alloy billets to machine my conrods from, I intend to use the stock caps as they are iron, but may not matter?!

I do plan to rebuild the engine exactly how it came apart for now, meaning I can get it running whilst I machine the rods etc, then plan a winter strip down.
TC

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bones
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Post by bones »

could you not find a bigger engine to use :?: :D . makes our v8 packages look so small :D .rich

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topcatcustom
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Post by topcatcustom »

Bones is back! I like to go against the grain Rich, just hoping I can get the aesthetics to work on this as I can't picture the front end working perfectly in my head! I was considering using a RV8 as a donkey engine :lol:
TC

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bones
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Post by bones »

you will find away of making it work. Extended front on a landy rat rod will look pretty cool, i can picture it and that will be one mean s,o,b. Some ??, where does blower fit, :D rich

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topcatcustom
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Post by topcatcustom »

The blower location- not quite figured that one out yet!!
TC

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Post by kiwicar »

Hi Tom
anything new to update us on :D just because you have a business to run, and a house to rebuild doesn't mean you can slack off on the important things in life :lol: come on more on the very narrow angled v8 part of the forum.
best regards
Mike
poppet valves rule!

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topcatcustom
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Post by topcatcustom »

Mike- you forgot the wedding that is happening in 8 weeks, and the 4 day stag do in Estonia I just got back from :? !!

There is a little progress actually, will post pics later, mainly discovering that the engine and trans is so long that I have about 60mm for a rear prop...!!! Oh the joys!
TC

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Post by chodjinn »

Mount everything solidly and bolt gearbox direct to the diff ... And buy some new teeth lol!
RIP MGB V8 .... served me well as a learning curve.

R32 Skyline V8 .... this one is gonna be a monster!

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Post by scudderfish »

topcatcustom wrote:Mike- you forgot the wedding that is happening in 8 weeks, and the 4 day stag do in Estonia I just got back from :? !!

There is a little progress actually, will post pics later, mainly discovering that the engine and trans is so long that I have about 60mm for a rear prop...!!! Oh the joys!
8 weeks between stag and wedding? Takes the fun of brinkmanship out of it :) Mind you the emergency passport I had to get after mine was quite pricey...

kiwicar
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Post by kiwicar »

Hi Tom
I hadn't forgotten the wedding, I just thought I wouldn't try and scare you on an open forum :lol: how are the plans going? Will you be allowed one choice on the menu? I was I was allowed to put Halibut on there. . . I think that was the only choice I was allowed to make!
best regards
Mike
poppet valves rule!

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