Fiat Tipo 16v combustion chamber dimensions

[Walezy]

Hello Guy,
Could you help me with getting some pictures of the combustion chamber with dimensions, angles etc. for tipo 16v head. I want to make custom pistons for my engine and this will really help me with making a proper dome for those pistons.
Thanks
Tomasz

[Guy Croft]

Give me the bore, stroke and intended CR please.

GC

[Walezy]

Bore will be 86mm(because i will use Chevy 350 H beam con rods, 6" long). stroke will be 90mm and about CR, well, I thought about something like 11,5:1 to 12:1 but maybe you can suggest something.
By the way. I want to use Total Seal gapless piston rings, do you have any experience with them?
Tomasz

[Walezy]

I have just called the company that will make me a pistons, all they need is a sample piston and a combustion chamber moulding(in fibreglass or in body filler) or combustion chamber "dimensional pictures". I was told that the piston can be made if the compression height will be 30,4mm which is what I need when using 6" rods. The piston pin will be chevy. I have already bought the rods, now waiting for delivery :) . I hope this will work good, for sure I will write about this engine while building it.

[Guy Croft]

Tomasz, ih

As you can see from the CR calculator (which I have also emailed to you) if you run a flat top piston flush with block deck, blueprinted valve seats, minimum reface on the head, 86mm bore gasket you're going to get virtually 11/1, I would not go any higher, intrusions into the flame front are going to just fight any potential gain in torque from higher CR.

The late 16v valve angles are 23.5 deg inlet and 22.0 deg ex.

Hope this helps,

GC

[Walezy]

My head was refaced a bit so it should be ok with flat pistons, and it is far easier to order such piston as I will not have to send a sample piston to make it.
Will it be possible to get about 200-220HP from such setup with using proper cams(any suggestions about cams- lift ,duration etc.) and with 4x44mm throttle slide plate throttles, fuel injected and mapped ignition.

[Guy Croft]

Tomasz, hi

it's certainly easily achievable, even with inexpensive Kent Cams BD3 profiles reground onto the standard n/a 16v cams I have had several cars with ported heads, 11/1 CR give 190bhp+ at the wheels - on DCOE 45 carbs. That should be your benchmark, a carb result - you should exceed that or the injection isn't doing anything.

Whether you get anywhere near that will be in the most part a function of how well you calibrate the fuel and ignition. Get that wrong and you'll get nowhere that.

GC