boost on f7p , standard c/r

[Schakal]

i want to spice things up a bit , some of you know i am running a standard
f7p 1.8 16v engine on my renault 9 ,even though its a daily driver and
the power is pretty much plenty on the road ,its not enough for track use

i have a few ideas to give me that extra power and one of them is sticking
a small turbo on low boost on the standard pistons which have a c/r of 10.5:1
any ideas if this would work ?
if it does what sort of maximum boost could i use without causing detonation etc ?

[Bigfoot]

Not worth the effort if you keeping at standard cr as det will be there straight away unless running very low, which will mean that you will only be making about 20-30bhp extra, you want to run about 9psi and think putting the thicker plate for the headgasket and skimming the pistons by 1mm should be fine for that.

[Schakal]

Not worth the effort if you keeping at standard cr as det will be there straight away unless running very low, which will mean that you will only be making about 20-30bhp extra, you want to run about 9psi and think putting the thicker plate for the headgasket and skimming the pistons by 1mm should be fine for that.

my bad the standard c/r on a f7p is 10.0:1

i have just found this

http://www.engine-dynamics.com/epage...0Conversion%22

if they can run a t28 on a 11.0:1 c/r ,why cant i run it ??

[Woznaldo]

You can be sure that's a low boost conversion and I'd be surprised if they're running more than 6-7psi? So yes you could run the 10:1 but only on very low boost.

[Schakal]

You can be sure that's a low boost conversion and I'd be surprised if they're running more than 6-7psi? So yes you could run the 10:1 but only on very low boost.

low boost is what i am after
so you reckon 6-7 psi is max i can run without ANY PROBLEMS ?
does not that therocially equate to just under 50% power increase
on the standard power minus the friction and heat losses ?
say 35-40% which is around 180-190 bhp

[Andrew Cooke]

high CR, small turbo, bad mix

[Schakal]

high CR, small turbo, bad mix

please do tell more

[boostjunky]

6PSI on a standard F7P would theoretically make about 175hp give or take.

[Woznaldo]

6psi on a T2 is not the same as 6psi on a T28 as the larger comp wheel will move a higher volume of air for the same pressure.

[allanr5gtt]

my bro is running 172 turbo 6/7psi with t3/t4 turbo on 9.5-1 cr and getting 255bhp.