Originally Posted by
Dyno Small example of what can be done with a simple 32/36 DGAV carburetor and turbo charger. I know it should have been tested on a Pinto and I should be driving a Capri or Escort as a track-day carb but unfortunately, I can't afford myself a Capri anymore at the current prices, let alone I would find the time to restore it. So for this reason I'm testing and driving an MX5. Basic all the rest is the same, so imagine the engine is Ford, not Mazda. Inlet manifold is a modified Zetec Banger manifold so small connection with Ford.
The engine was making +/- 125 Bhp without the turbo (and 32/36 DGAV). With a boost figure of almost 700 Mbar the engine is making over 260 Bhp and 285 Nm. Not bad for a stock engine (lowered compression 8,5/1 and 2mm shims under the valve springs).
The biggest issue was trying to get enough fuel for 260 Bhp into the float chamber. Remember, your twin Webers both have a float seat and needle, here all has to be pushed over 1 needle. At around 220-230 Bhp the problems started. Also the reason I did not tested at any higher boost. I'm currently solving the problem by using a modified EFI "raising rate" fuel regulator. When boost comes in, the fuel pressure raises more as just the compensation for the turbo boost. On the dyno I was using a very large seat / needle and as higher as recommended fuel pressure. On track it will not be stable enough.
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