Originally Posted by
Leon R
Those are some low numbers (for base boost and power). I have been hearing 5psi with a basic Alpine kit. As HP figures, which dyno are you using? DynoDynamics?
Have you guys considered using AEM FIC for tuning? It is a piggyback system with a much better approach than the old Apexi AFCs.
We are always conservative in power claims Leon
While the numbers seem low the gain in power is close to 30%, which is not to be sneezed at.....Seriously though there is a method in the madness
You have to consider what environment we developed for - it was quite a simple idea - the main target (don't laugh now) was to be able to achieve 'float speed' over the infamous corrugations on the Canning Stock Route, about 105 km/h is enough speed to skim the tops - in the bottoms is a fine clingy dust that is worse than mud for rolling resistance, you either do 100+ or 20, anything in between shakes everything to pieces
With a truck loaded for two weeks camping even redlining third before picking fourth she simply didn't have the grunt to hold float speed even at WOT, with fuel use around 35 litres per 100
Even with 280 litres of fuel tankage that's not enough. Fuel depots can be 1000-1200 km apart out there.
It is possible to get a very very long way from the nearest human/fuel/beer etc in Australia (Well, maybe not the beer) so the first priority was bulletproof reliability
Here we found that 5psi was 95% or more injector duty cycle, with the start of detonation audible in the headphones so we took 80% duty cycle and no knock at all on 91 octane as the base. In parts of the Outback the only fuel is a product called Opal (developed as a fuel you cant get high from sniffing...a problem in some of the Indigenous communities...you can fill in the blanks there!) which is in the 80's octane wise, so we considered that sometimes you might have Opal mixed with your 91-to-98 octane good fuel, or a whole tank of the stuff.
All the kits we fitted we did 'before and after' on our own Dyno Dynamics.
My own truck dynoed at 134hp before, 175 after on 3.3psi at 81% duty cycle
The truck that did the Stock Route did 128hp before, 174 after, 3.2 psi and 80% duty.
On a revisit to the CSR last year he found that not only could it achieve the required speed in fourth it did it at 40-50% throttle, and returned 22l per 100. This despite having added a rooftop tent and roof rack.
Mission accomplished
The answer is more power! What was the question?