For the last month or so, I’ve been thinking about a basic engine upgrade on my 1990 3.6..., which, as far as I can see, will boil down to exhaust cam gear and chip, as it appears to offer the best HP/£. (or does it ....?)
The only problem is I have is the mass of conflicting results published on this forum..., everything from +54 BHP, to ' no noticeable difference at all !'.
Two points :
1) As far as I'm concerned, cam timing is cam timing, plain and simple..., this is a good thing, so an exhaust cam gear providing more 'overlap' should produce consistent results on several examples of the same model motor.
2) Chips..., this is where I think the problem lies. All aftermarket chips are designed/mapped on only a handful, or possibly only one example of the car they are designed for. It's plain to see from any 'dyno shootout' session that if you take 10 stock cars, every one will produce a different power/torque result.
So, finally to my point....
Has anyone considered/used a piggyback ECU (eg. Unichip) on their M5, and had it properly mapped on a dyno ?, as I feel this would provide the best possible result for that _particular_ car.
Linear Mode
