I know this isn’t a Clio, but I’d appreciate picking your brains anyway.
A friend has asked me to build them a turbo engine for there Nova, I’m going to do it, but If I do, I want to make it powerful and reliable. To do this I have a few questions.
I had a look at two Turbo’d (previously normally aspirated) 1.6 8v Nova’s over the weekend. Neither could run high boost, and they were both setup differently. The two ways people approach this are different. The bodge job is using a plate and two head gaskets to lower the compression. The other way is to use low compression pistons. I have worked out that if I use a 1.6 head and a 1.3 bottom end, I can drop the compression to 8.1:1 Is this low enough?
One of the the cars increased fuel on boost by running a fuel pressure regulator plumbed to the pressure side of the turbo. The other also had this, but also had a pressure activated reed micro switch that appeared to be wired via the throttle position sensor. Is this needed, and how does it work?
The final question I have is related to ignition. The only reason I can see that the engine using low comp pistons wasn’t working is the ignition. The setup seemed unchanged from normally aspirated. I thought that the ignition had to be retarded on higher boost. Is this correct, and if so how much? Would it be enough to disable the mechanical advance, and if not, what do I have to do to solve this problem.
Both cars were quite fast, running about 15.5 1/4’s but were limited to 9 or 10psi or they would blow a gasket or crack a piston. There was nothing else done to them and they were using the standard ECU
Any help would be appreciated.