All my cars and engines if you want to use an engine private message me and i can give you specs and help.
My first after many hours maybe day of messing with engines and making cars i got this. 
engine will be posed soon
Are you not paying any attention to weight and production units? For nearly 1k horsepower that is incredibly slow.
Your problem is that you’re trying to get that 950 hp to the ground with front pair (!) of rather average sized tires. Try changing drive train to RWD and making those rear wheels wider. 0-62 time should improve massively.
Whoo there’s a lot of madness going on here, and I do like madness, but if it’s unbalanced, the car simply won’t be as fun or capable. To add to what the others have already said:
The car is nearly 2 tons, it’s FF, it has a 943hp engine, it’s a supercar that does 200mph, and the front tyres are 255mm wide. You’re probably getting a lot of wheelspin off the line (check the detailed stats, it might be somewhere in the ballpark of -30% penalty to tameness), and for the kind of car it is, the cornering capabilities indicate that you could probably optimise the suspension and downforce quite a bit (check the bump and yaw graphs as you test)! I’m guessing you’re getting 2:40 or more around the test track? Even with a FF car, see if you can get it closer to 2:20.
And if you want more out of the engine, yes, perhaps it might make it less reliable, but lifting the limiter by an extra 600-1000rpm will give you significantly more powerband to play with, as long as the tyres have enough traction to put that power down!
Also, you oughta learn what works best when it comes to engines as opposed to chucking the “best” parts on it (5V DOHC, DI, Throttle per cylinder etc)
Well, that really depends on what you’re looking for. In terms of sheer power output and hang everything else, you can’t compete with a DOHC 40v V8 VVT direct injection throttle per cylinder race intake setup 
Of course, but seeing as it’s a 3.6 I doubt he’s going for something capable of breaking records 
Tuned engine more - done
It lighter - done
Thicker Tires - done
RWD - done
cooling -done
this is what i have done and its made my car a lot better thanks…
You definitely want to get the balance between boost and max RPM right, and for the latter you’ll have to figure out the stroke and the strength of your bottom end parts. Right now you have a very narrow power band which doesn’t maximise before the cutoff, meaning either your turbo needs to spool earlier (reduce the size of the turbine), or your engine needs to have a higher rev limit.
ok iv done a few changes is this a bit better also how can i increase Reliability with out to much loss of power.
Put more grilles/vents on the car. You.can put kind of.stack them.on top of each other so you get more cooling but it will look like you only have 1 vent there.
im planing to try inline 6
You can try reducing stroke for high-revving engines or tweaking your turbo in order to adequate to your engine needs.