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General => The garage => Topic started by: dub fatha on 23 September 2008, 19:07

Title: 20v turbo compression ratio / forged piston question
Post by: dub fatha on 23 September 2008, 19:07
hi again

need some help with a forged piston/compression ratio question that i have,

as far as i have been told the stock compression ratio for an AUM 20v turbo engine with 150bhp is 9:5:1 .

i wanted to fit some forged pistons with a lower compression ratio so that i can run higher boost, but am not sure what ratio to go for,

i am going to be running a turbo/management set up that will give me around 400 bhp with a 50 bhp nitrous kit.

am going to the states next month and was going to purchase a set of JE pistons from over there, which have a compression ration of 9:25:1, or have found another set which have a ratio of 8:5:1.

i would be very greatful if someone could point me in the right direction in regards to which ratio to go for.

many thanks

dub fatha
Title: Re: 20v turbo compression ratio / forged piston question
Post by: topher on 23 September 2008, 19:27
Get a hold of a copy of this months Golf+ magazine.. there's a huge article on 1.8T tuning with input from all the biggest tuners.
In a nutshell, either of those CR's will do, but you really want uprated rods too, and head studs, and valves if you want reliability.
Title: Re: 20v turbo compression ratio / forged piston question
Post by: danny_p on 23 September 2008, 19:38
8.5  : 1 for 450 bhp
Title: Re: 20v turbo compression ratio / forged piston question
Post by: dub fatha on 12 November 2008, 20:02
nice one for the info guys,

a few other people have told me to go for 8:5:1. so thats gonna be the magic numbers for me :grin:.
p.s sorry for the late reply