David_Wallis

Yeah 1 was me

Andy.F

lol, I got the same comment from the Skyline guys

P20SPD

iTrader: (1)

for different reasons though

MartynJ

As a relative newcomer to the world of mapping in comparrison to the likes of Pat and Andy F (Although I have spent most of my life around the rolling road tuning game) I would like to raise the following question...
When you are running a car at this kind of level (Never yet seen a Scooby with more than 400bhp on our DD dyno) what are the hp benefits of running it at 12-1 in comparrison to 11.25-1 my preferred level...
Are we talking 5-10 hp or far greater than this...

swisstonihasher

I've been interested in the answer to that one!!?

Andy.F

There is no exact value that can be put on this, it will vary from car to car, it will vary even on the same car with different fuel. It is a delicate balancing act with timing, AFR and boost.
Some cars need much less ignition timing with a slightly leaner AFR, in this case leaner fueling is less likely to gain much in the way of power. Some set ups have MBT timing virtually unaffected by AFR..... up to a set boost level where things may go downhill quickly. Then there are some that just don't sound right unless they are rich as hell, possibly due to injector imbalance or some other cylinder to cylinder variation.
Pretty much the same as you will find on the 300-400bhp cars Martyn.

Andy