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Discussion Starter #1
Are the camshafts the same on different engine sizes?

eg. if I buy a set that is advertised for 1.5, would they fit the 1.7 too?

I'm getting some mixed opinions with google :rolleyes:
 

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The 1500 ti Green Cloverleaf meachanical cams (105bhp, single lobe) will fit a 1700 8v so long as you use the mechanical valves and cam boxes on the 1700 heads.

The meachanical valve cams and the hydraulic valve cams are different.

the 95 BHP 1500 cams (twin lobe) will not fit a 1700 8v
 

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I had the same question and foe a long time i could find answer until i happened to get hold of 1.7 mech tappets heads.

So the answer is that you cannot have 1.5 mech tappets head on 1.7 because 1.7 requires chambered ones and the pistons have , accordingly, different design. The opposite is doable , having 1.7 heads to 1.5 as it will increase capacity to 1600 and drop the compression rate.
 

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...The opposite is doable , having 1.7 heads to 1.5 as it will increase capacity to 1600 and drop the compression rate.
Changing the heads WILL NOT change the capacity of the engine.
The engine capacity is the swept volume of the pistons, a 1.5 is still a 1.5 even with the heads removed, but obviously no compression...!!
 

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Discussion Starter #6
Yes, IE engines 91 onwards to be specifig
 

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Changing the heads WILL NOT change the capacity of the engine.
The engine capacity is the swept volume of the pistons, a 1.5 is still a 1.5 even with the heads removed, but obviously no compression...!!
Ok, but when you have flat heads and change them to chambered ones keeping the same dished pistons from 1.5 doesnt it increase a little the capacity of the chamber and drops the compression rate a little?


Cause it is one of the things i would liek to do also , my valve seals on 1.5 heads i have are shot and needs service but i have a fully serviced 1.700 mech tappets which i am thinking of using. The only reason i havent so far is that i thought it will change engine behavior by dropping compression rate due to different combustion size..
 

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Discussion Starter #9
Another question..................... Related somehow................

How does one check the condition of the camshafts? eg. what should I measure with a micrometer and what kind of readings should I see? How do I check that the shape of the cams are correct?
 

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Ok, but when you have flat heads and change them to chambered ones keeping the same dished pistons from 1.5 doesnt it increase a little the capacity of the chamber and drops the compression rate a little?
It will change the compression ratio, but the capacity of the engine remains EXACTLY the same.
The capacity of the engine is the swept volume of the pistons, NOT the volume of the combustion chamber.
 

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Pasi,
Worn cams often have a pronounced point on the tip of the lobe. It is easy to feel with your fingers. If the lobes have a nice rounded tip and no evidence of scuffing on the bearings then they are probably OK.
I have found that the tappet shims (and followers on hydraulic engines) can wear as well. Check that they are flat and don't have a depression in the centre of the working surface.
 

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Discussion Starter #12
One of the cams that were in the engine has a "razor" sharp tip to it, so I know it's busted. However I just remembered that I have a set of camshafts from another 1.7 engine, so I need to check their condition.
 
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