Does AFM bluetop have lower comp pistons than the MAP bltp?

[jamiemirror]

El_Camino Wrote:Same story again. The european AE86 forums dont knowing which CR are their engines.

I started the thread bevor, so I made sure i get as much as possible information and pictures from such engines. For me, without any doubt the answer is 10:1.

But you never ever touched these pistons.

[firehawk]

Ok, here's what I've concluded on;

- The 9.4:1 piston has a slightly dished crown (increases the CC volume by 1.6cc).
- The 10.0:1 piston has a similarly domed crown (decreases the CC volume by 1.6cc)
- The 10.3:1 redtop piston has a similar crown to the european bluetop one, but with a slightly higher dome (decreases the CC volume by 3.0cc)

Below are some photos for illustration - you can clearly see the difference between the 10.x:1 ones and 9.4:1 ones because the centre of the piston's crown is actually recessed below the rim of the crown.

[Apolan]

great, now just tell us which cars had which pistons.

SO are all bluetops in europe 10:1 than? Even the AFM ones? Or was that i thing restricted to a US market? What about Swiss and swedish cars? 9.4:1?

[Ivan141]

Photo nr 3 is mine.. came out of my first engine (275.000 km).
I still have those here in my room.

[dreja]

Apolan, Swiss cars are 4AGEC (note the C !!!), yours european is 4AGE (without the C).

In difference to US 4AGEC there's no catalytic converter in Swiss 4AGEC. For the pistons get a VIN number of US car with 4AGEC and we'll look in EPC the piston's part number...

[dreja]

If helps I'm posting the two vacuum hoose information. The red one is Swiss 4AGEC (tnx to Ryo ), the blue one (found on club4ag) is USA 4AGEC vacum hoose information:

[dreja]

To complete the list it would be fine if someone could post the diagram of European 4AGE...

[Apolan]

yes but i want to know if all AFM-type bluetop engines had 9.4:1, or was that only for swiss and US market..

[dreja]

Were AFM type engines sold also in other EU countries ? Which ones ?

I know for Swiss and Sweden (SDZ market). Any other?

[Apolan]

beats me, thats why im asking.. wonder where the hungarians got their cars from..