Race Engine Forum UK

Hi all,

I have just purchased a used 1600 SOHC Tipo engine which I plan to use as the base for my next engine in my 128 Circuit car.
Apparently the 1600 block is prone to cracking, I understand poeple take the 1600 crank out and put it into a 1500 block with 1100 rods etc etc. The casting are certainly quite different.

My question is . Is this actually nessarcery? or is the 1600 Block up to the job and the cracking is just another mith.

Looking forward to your comment,

Andy D

Well, I don't go for these 'prone to cracking' stories because no-one has ever id'd cause and effect to me in any kind of 'scientific' way.

GC says:

Blocks can when:

1. They get frozen in winder
2. Cranks and rods break
3. They are hard bolted without rubber isolators.
4. You hit them with a sledgehammer.

As for the 1600 Tipo I know of one that runs one bored to 88m bore - 1640cc, steel crank and rods, forged pistons (of course), 13.7/1 CR, GC big valve head, Piper BP320, Jenvey 45mm inj, genuine peak 175 bhp at 7900, peak T 133.5 lbf ft from 5-6000rpm, 170 bhp @ 8500.

So far on 3 events has broken the Uno Turbo 5 spd Bacci gearset, both driveshafts (twice, small & medium, large going in next) and vertually every part of the car structure at the front end. The block has not cracked.

Hope this reassures you,

G

Andy128 wrote:I understand poeple take the 1600 crank out and put it into a 1500 block with 1100 rods etc etc.

Just a small remark, for stroking a 1.5 engine to 1.6 you only need the 1.6 crank and pistons (smaller compression height). The rods are the same. All SOHC engines use the same lenght rod (~128.5mm if I remember) exept the 1.1 and 1.3 with 55.5mm stroke (they use 120mm). 1.3 turbo with 63.9mm stroke also uses the longer rods.

Uros

Thank you both for your replies. Guy - your friend's engine is far more radical than what I plan to build so I think I can simply forget about the cracking stories.

Once again thank you

Andy D

I am having a Fiat Tipo 1580 SOHC engine put together for a race Fiat Uno. Its not as high spec as the good Doctors, unfortunately, as it has been built to a low budget. Whilst on the Dyno all was running OK for a while until the oil pressure dropped suddenly. It was switched off and the engine stripped down. A crack was found in the block - a casting flaw perhaps(?) - which may have been opened up when the block was heat treated. This was "stitch welded" and machined and the engine re-assembled. I'll let you know what the results are when the job is finished.

I'm afraid that I don't know any more details as I am not doing the job....just paying for it!