tutuur
12-11-2011, 08:15
Hi guys,
I already have a full forged engine to go in my 5 but i want to do a bit of a budget build so i can enjoy turbo power in the 9 for the time being.
I already sourced myself an meggie engine and torn it apart.
Turbo, manifold, DV, injectors, chargecooler, fuelpump etc. Has already been bought.
I'm picking up new bearings and piston rings next week.
As for lowering the compression i used some formula's to know how much material should be machined of the pistons to give a CR9:1
As a willy piston is dished i want to keep it that way, my plan was to machine 1.25mm of the edge and then deepen the dish by 1.4mm.
As for my calculations that would be 7.2cc which provides the CR to drop to 9:1.
Now for the guru's: the thickness of the piston bottom is 7mm, what's the least i want the thickness to be?
I also considered machining the dish 1mm which would see a CR9,4:1.
I think this would be fair low enough for 8-10psi max considering VAG 20v's have 9,5:1 and can produce 280hp max on standard internals...
Thanks in advance for the advice!
I already have a full forged engine to go in my 5 but i want to do a bit of a budget build so i can enjoy turbo power in the 9 for the time being.
I already sourced myself an meggie engine and torn it apart.
Turbo, manifold, DV, injectors, chargecooler, fuelpump etc. Has already been bought.
I'm picking up new bearings and piston rings next week.
As for lowering the compression i used some formula's to know how much material should be machined of the pistons to give a CR9:1
As a willy piston is dished i want to keep it that way, my plan was to machine 1.25mm of the edge and then deepen the dish by 1.4mm.
As for my calculations that would be 7.2cc which provides the CR to drop to 9:1.
Now for the guru's: the thickness of the piston bottom is 7mm, what's the least i want the thickness to be?
I also considered machining the dish 1mm which would see a CR9,4:1.
I think this would be fair low enough for 8-10psi max considering VAG 20v's have 9,5:1 and can produce 280hp max on standard internals...
Thanks in advance for the advice!