Higher compression

[ToddT]

I have a '95 F-150 with a 300/5-speed. I do a lot of work with renewable energy. I bought this truck as a test mule for two different types of renewable energy: straight ethanol (no gasoline) and wood gas (biomass gasification). In both cases, higher compression is better and advanced timing help a lot.

How do y'all suggest raising the compression? Deck the head? Swap pistons? What compression ratio could we safely go to?

[Fellro]

Piston swap is the most common and effective way to raise compression. Good luck on the 100% ethanol, it is federal law that any ethanol for fuel must have 15% gasoline to prevent drinking it. If you make your own still, you better get a permit or ATF will be on you about it. You should be able to find potentially into the high 10's to 12:1 pistons. Don't outright recall where the optimal for ethanol is, but seems to me to be in that territory. main trick is finding such for a 300. It would be easier to find the high compression pistons like that in the V formats.

[ToddT]

As for the ethanol, you only need 1% gasoline or some other denaturant to make it legal (non-drinkable). My ultimate goal is to have a functional vehicle that can run on locally produced fuel. I have well over 200,000 miles running my F250 on veg oil. The truck has almost 300k on the clock and I'm on the original injectors. I use a two-tank system with heat as well as biodiesel and a veg oil blend.

I was hoping Jacobs might have some high compression pistons but they only have intakes, carbs and cams. Thinking of the V-8's, any idea of the 300 pistons are used in any other engine. Figured solely on cubic inches, a V-8 version of the 300 would be a 400c.i.d. engine.

[Fellro]

I tried to buy straight ethanol from a local plant once, and they had told me that, plus they discharge fuel way too fast for anything less of a tanker truck.

I do not know that there is any commonality between any other motors, and tend to believe there is not. Wrist pin location and bore diameter are the key factors.