Friday 12 May 2017

Warning: Like a fiend for nicotine, power figures can be addictive.

Thought it would be a jolly wheeze to see what the maximum potential of the car would be in it's current form. Okay with a couple more modifications to it's fueling.

To that end I fitted a bigger 100mm core intercooler (Misimoto R Line) and 450LPH fuel pump (Walbro).

Both jobs were a pain in the butt to do, Although probably not world ending and certainly do'able at home they were both awkward to get at and both needed 'special' love and attention to detail.

Intercooler. As a standard generic fit I could just about squeeze this into the front space 'as was' already cut for my old Japspeed intercooler. The fittings being slightly different I did have to drill a couple of holes in the crash bar (after making a bazillion measurements) and fabricating a couple of brackets from some flat Iron bar (they aint going nowhere). Biggest pain was the front bumper, after a trim and refit it wanted just a little more off.. five goes later and job done.
Of course the fitting of the intercooler didn't really help the horns much and having previously made a gorgeous bracket to mount my 'Scooby' horns on. It soon became apparent that they were not looking great being squished by the intercooler (these have since been removed for an alternative horn).

Fuel Pump: Although aware vaguely that there was a wiring mod, this was not initially done and we soon found out why it is required as the 450 lph pump can't draw enough voltage to pump the fuel.
So just a side note, if you’re installing a current hungry fuel pump I suggest the fuel pump be wired using a relay directly to the battery. The stock wiring and fuel pump controller cannot cope with the new current draw resulting in a drop in voltage causing lack of performance and further issues. Or in my case less HP than when I started!
Here is a good link for the actual process of physical fitting.
Here is a good link for the wiring direct feed.

Awaiting Dyno and the last view of the horns!

Results: Well things were not exactly running super smooth on mapping the car. There was a boost leak due to a few pennies worth of cable tie. The car then failing to deliver enough fuel and after the wiring modification, the car still refused to deliver enough fuel, with the injectors (850cc Denso's) being at capacity.
Having already eaten up a good chunk of dyno time for practically zero gain and all loss, we upped the fuel pressure. Now we were nicely back on track. However, this meant that the fuel map was no longer any good and the 'tweak' to the map was no longer an option. A full map it was to be then.

Dyno readout taken at hubs
So all in all a big bill, a lot of work and an actual 12HP more. Although for the increase in torque it was probably worth it (this is what I tell myself). People get so hung up on BHP it actually does not mean a lot when you get past a certain level. Or put as a very simple example: Two engines may have the same torque to pull up a 1 in 4 slope, but if one has more BHP, it will pull the car up the slope faster. Torque is a measure of the force available to accelerate the car.