Omega forged pistons
Turbo Mini Forums

My engine guy had just rang and said there is a 4/5 week wait
On pistons any one no of any news floating about or any one with them in stock
My engine is 1293

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=445578

Tried MED? they should some in

Matt W

I just got some +40's from med no probs.

Audi s4 b5 - 470bhp & 486ft lbs

On 30th Apr, 2012 Brett said:
yeah stick the bit in and give it a wobble

18cc omega forged pistons 3/4 weeks just got off the phone to them

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=445578

Why do you want 18cc? What cc in the head and what cr are you aiming for?

Edited by bennyy on 13th Feb, 2012.

Audi s4 b5 - 470bhp & 486ft lbs

On 30th Apr, 2012 Brett said:
yeah stick the bit in and give it a wobble

Omega have told me they only do 10cc and 18cc if I go for 10cc I will have to port the head out more and run the risk. Of hitting a water way so best stick to 18cc and bring the block down! Also 8.5-1 and 21.1 cc a chamber but block needs work to get compression ratio right

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=445578

Porting the head is not the same as opening out your chambers, standard head and 18cc omegas gives you a cr of about 7.8:1, you need 10cc omegas with 25cc in your head for 8.55:1

There is loads to come out of your head, most run 26cc/28cc on here.

Audi s4 b5 - 470bhp & 486ft lbs

On 30th Apr, 2012 Brett said:
yeah stick the bit in and give it a wobble

You'll also find that if your block is standard/undecked then the 10cc Omegas actually sit around 0.040" down the bore & give a volume of about 14cc inc the dish.

Phil.

WWW.TURBO-MINI.COM

It was going to be decked but I'm going to talk to him later and c what is the best way to get the cr as he may have been going about it the wrong way thx guys for pointing that out I had over looked that! What would u guy recommend as I am only after 130/50 bhp on a t2

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=445578

those pistons as phil says sit down the block 0.040" on 73.5mm bore thats another 4ccs to add to your calcs.

if you have standard 21.9cc in the head chamber here are a few calcs for you to concider ......... hope this helps you

if you deck the block 0.030" you compression is 8.08:1

if you deck the block 0.040" your compression ration is 8.23:1

without decking the block which is bad for detonation in the A series engine, on the threshold of maximum boost your compression ratio is 7.63:1

I didn't wanna alter the chambers as I want a very strong engine everything has been over engineered as the head would be strongest as it is it has be gas flowed polished and ported with bigger inlet and out let and I'm looking 12/15 psi as my turbo is t2 also thx benross so to get my cr i need to deck 0.050 as every 0.010 adds 15 to cr if Mathis is right

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=445578

If you deck the block 50thou your pistons will be proud. You need to open the chambers in your head. This won't cause any reliability problems.

If something is worth doing, it's worth doing half of.

Thx so what is a safe amount to open chambers in head?

http://www.turbominis.co.uk/forums/index.php?p=vt&tid=445578

Up to 28cc seems to be the accepted maximum whilst keeping a decent chamber shape.

If something is worth doing, it's worth doing half of.

if you are leaving the combustion chambers the standard size 21.9ccs
get the block decked 0.030 this gives you 0.010 for scope on high revs, the rods and crank flexing,

you cr as above 8.08:1

there are MANY!!! combinations of engine builds specs etc ...... your is just one if its your first build iam sure you will be please with the motor performance wise if you build it correctley with the rest of the good guy internalls....etc