1800 head

[engineerted]

Yes you are correct, but that would be the 1592 head with the 84mm bore, In the USA the 1600 head is the 80mm bore head just to make things clear. Thus fitting a USA 1600 head on a 1800 or 2l would require some coolant passage modifications.

Ted

[BEEK]

Yes you are correct, but that would be the 1592 head with the 84mm bore, In the USA the 1600 head is the 80mm bore head just to make things clear. Thus fitting a USA 1600 head on a 1800 or 2l would require some coolant passage modifications.

Ted

the 1592 uses the same coolant passage allignment as the 1800/2000

[swede]

Swede,
The head in your second photo is not a 1600 head, it is an 1800 head. The 1600 head has symmetrical bowles, not offset in 1&4 as shown. Sorry dude.

Ted

Ted.

It should be a 1600 head but I will investigate the head number when Im home again.
Does anyone have a referenslist on head numbers?

[Kent124]

Here you go Swede: http://www.mirafiori.com/faq/content/headid/headid.html

[swede]

Here you go Swede: http://www.mirafiori.com/faq/content/headid/headid.html

Okay I found it on this site.
http://www.cars-data.com/en/fiat-ritmo- ... specs.html

It’s coming from a Fiat Ritmo 105TC (1600) and should fit my 1800 without any modifications, it will give me slightly higher compression ratio and better flow thanks to bigger intake valves (43.5mm).

[wmausbach]

Ted and Beek,
The 1592 engine was identical to the 1756 in all respects except a 80 mm bore and a 79.2 stroke. The block was identical with the same offset bore centers. The head is identical to the 1756 cc engine. That is why the 1608 is considered the best engine as the combustion chambers were centered over the bore.

The 84 mm bore engine was a 1585 and had a 71.5 stroke and was only used on the Strada (Ritmo) Abarth 105 TC and some Lancia models which was never imported to the US. The head did have the 43.5 mm valves though and I understand it is the best stock head from a port design. The same head was then used in the 2000cc version (130 TC)

Ciao
Wayne

[BEEK]

actually in the 1592, the combustion chambers are centered over the cylinders too,

[opus10583]

actually in the 1592, the combustion chambers are centered over the cylinders too,

How?

Was the casting specific to that engine?

Thanks,
Mark

[BEEK]

the 1438, 1608 and 1592 use the 80mm bore, the head was designed for this bore spacing. fiat bored the block to 84mm, this spacing offset the combustion chambers , the effect was not enough for fiat to retool and remake the head casting equipment. so fiat just basically bolted the same design head on all blocks, the combustion chambers are not centered , but the offset is not enough to cause major problems, in a perfect world, the head would be remade to center the combustion chambers. guy croft , makes pistons (high compression) for the offset configuration. for the best performance.

[opus10583]

the 1438, 1608 and 1592 use the 80mm bore, the head was designed for this bore spacing. fiat bored the block to 84mm, this spacing offset the combustion chambers , the effect was not enough for fiat to retool and remake the head casting equipment. so fiat just basically bolted the same design head on all blocks, the combustion chambers are not centered , but the offset is not enough to cause major problems, in a perfect world, the head would be remade to center the combustion chambers. guy croft , makes pistons (high compression) for the offset configuration. for the best performance.

Hi,

My understanding is the 1592/1756/1995 "132" block is longer (and taller) than the earlier "124/125" block with increased bore centering, thus offsetting the chambers of all three variants as the head was not manifestly changed as well.

If they just bored the block the centering wouldn't change.

Ciao,
Mark

[fiatfactory]

.

[BEEK]

1592 headgasket


1608 headgasket


1995 / 1756 headgasket

[FiatMac]

From PBS-FIAT 124/131 TWIN CAM RACING ENGINES brochure:

Two different stock bores and four different strokes are used in the five engine sizes. The 1438cc, 1592cc and 1608cc engines all have a stock bore of 80mm. The 1756cc and 1995cc engines have an 84mm bore stock. The strokes are as follows: 1438cc - 71.5mm, 1592cc - 79.2mm, 1608cc - 80mm, 1756cc - 79.2mm and 1995cc - 90mm.

The 1592cc, 1756cc and 1995cc engines all have the same bore spacing, which is greater than that used on the 1438cc/1608cc engines. The 1592cc and 1756cc engines use the same crank and rods and the same block height. They, basically, differ only in bore size. However, the 1592cc cannot be bored to 1756cc as the water jacket is different. The 1995cc engine has a taller block, a larger crankcase and longer rods as well as the longer stroke.

The cylinder head combustion chamber spacing is the same on all of the twin cam engines. This spacing is matched to the 1438cc and 1608cc series engines. Hence the end bores are offset somewhat from the centers of the combustion chambers on the 1592cc, 1756cc and 1995cc engines. The basic cylinder heads are physically interchangeable between all the different sized engines except for the water jacket opening at the front of the head at the head-block interface. The 1438cc and 1608cc heads have a larger opening at this location which is too close to the front cylinder to be used on the 1756cc and 1995cc blocks.

As noted before the 1438cc and 1608 cc heads can be modified by welding of the water jacket opening to allow use on the other engines.

The entire text can be viewed at http://www.mirafiori.com/pbs/pbsdohc.html

[opus10583]

What are you implying this demonstrates?

1592 headgasket


1608 headgasket


1995 / 1756 headgasket

[wmausbach]

FiatMAc,
The PBS article was written based on their experience (Calf.). The 1585 was never imported hence the brothers never saw one. I used to talk to Paul quite a bit when I was racing. Like Steve noted that engine was used extensively in the 80's and 90's. At that point PBS was not in the development mode for the 124 engine.
Ciao
Wayne