High Comp 1.4 CGA3

[AJC]

Anyone got any what pistons/rods would fit if any to make a high comp CGA3, looking for something like an 11:1 comp if poss, still gonna be doing my turbo conversion, but would be interested to see if a high comp 1.4 would compete with a low pressure 1.4 turbo

 

[Chops]

i think the rods are all interchangeable, but the 1.4 has a wider bore, so you'd have to do a ebb style piston weld job for flat tops.

 

[AJC]

Yeah i know the bore is wider, was just wondering if anyone knew of any pistons that would be a direct fit, or any combo of rods/pistons that would get close to my comp i want, being a daily driver and a poor college student, albeit at 36, i need my car on the road, so i cant really experiment, until i can get a spare cga3 lump

 

[Skinner_87]

Could raise it like I have by skimming the bloc and head a little though I havnt got a final comp ratio yet as I need to measure the head

 

[Chops]

chop der block! i have a place near me that will take a mm or two off for 40 quid, if i give them the block or head ready to go

 

[Enuo]

If you chop too much off head or block chain tensioner won't work no?

 

[Chops]

If you chop too much off head or block chain tensioner won't work no?

i shouldn't think so, I've removed the tensioner when i changed the cams in my old car and it has quite a lot of travel on it.

 

[Skinner_87]

chop der block! i have a place near me that will take a mm or two off for 40 quid, if i give them the block or head ready to go

I was talking thou rather than mm

 

[AJC]

Been looking at the Cube X spec CGA, they quote a comp of 10:1 and just over 100hp, i know they had a tubular manifold on them, so that helps get that power. Looking at the bore and stroke of mine and the cube cga, and they are the same, so it looks like the clearance volume in the cube is different, at 37.46cc if i worked it out right, whereas the normal cga has a clearance of 39.66cc, a 2.2cc difference. Could that be taken off the standard CGA head to get that compression?

 

[frank]

what do you mean by clearance volume AJ ? the cube alpha probably had a smaller dish in the piston

 

[AJC]

Clearance volume is the space enclosed by the piston and the cylinder head at TDC, also called the volume of the combustion chamber, sorry its how its been drummed into us at college

 

[AJC]

But yeah you are probably right about the dish in the piston, is there much of a dish on the standard CGA pistons then frank?

 

[frank]

i think the combustion chamber is about 24cc mate, then you have to add the dish (9cc iirc) and the head gasket eh

 

[AJC]

Just edited the post, to reflect the correct volumes, maths was never my strong point, that's what i get for rushing my calculations