cgrey8 wrote:Yes, it was built to be a high compression torque build...and the hope was that it'd be a fuel economy build too. Unfortunately, the fuel economy isn't as good as I'd hoped. It's not horrible, it's just not as good as the 302. I'm getting 21.5 MPG on the daily drive. Add to that, this engine requires premium. The 302 got 22-23 on regular.
I also don't like the very-low RPM performance. As long as the RPMs are above 600, it runs just fine. But if the RPMs drop into the 500s (i.e. taking off from an up hill stop), I can't load up the engine with the clutch & rely on a solid low RPM idle to hold the engine still while I transition my foot from brake to gas.
Add to that, the 331 and torque cam produces significantly more vacuum than the 302 at idle. Normally that's a good thing. But it pulls down noticeably more air at idle making it idle at a higher RPM than the 302 for the same throttle blade position. The 302 would idle at 550RPMs and pull down ~15-16kg/hr of air. The higher vacuum of the 331 pulls down 20-21kg/hr and idles around 700RPMs. I backed the throttle blade down as far as I could, but then the throttle plate started sticking.
I could lower the RPMs by lower idle spark advance. But this engine really wants high spark advance. The 302 was happy with 19-20 degrees advance at idle. The 331 seems to want closer to 28. If I retard the timing down to 20, the RPMs drop, but the air consumption stays the same...20-21kg/hr. If reducing the RPMs doesn't reduce the air consumption (and subsequently the fuel consumption), then I'd rather have the higher RPMs.
As for the NatGas conversion, the injectors and tubing have been installed ever since the engine got put in.
What's not installed yet is the tank, tank mounts, high pressure gas line, NatGas regulators, and electrical wiring. The hope is the tank will get installed this coming up weekend. I don't know if I'll get all the stuff installed this weekend, but that's the biggest piece I simply can't do myself because it requires pulling the bed and lifting a 160lb NatGas tank into the bed and mounting it down.
Also notice in the pic my very cheap PCV oil separator. That's actually a water separator for pneumatic air tools I bought off eBay. I got 2 of them for like $5 each. Add some barbed fittings I got from Lowes, that BTW cost more than the separator did, and I have a working PCV oil separator. It even has a schrader valve in it to drain the oil out when it collects enough to dump. I couldn't find a clear in-line PCV oil separator for less than $80.
What cng kit are you using? I am planning on converting my ranger to LPG (propane). I converted my car last year and I have been saving big $$$ since I am able to buy LPG for $0.69/gal. My ranger is carb so I am planning on trying the older suction conversion first. If I don't like it I will do the sequential injection. My Camry is using the Versus kit. It is pricey but a nice kit. In the past 16 months that I have had my kit installed on my car, I have driven it about 50,000 miles. Last oil change I went 15,000 miles and I sampled the oil and it was still good. I am planning on 20,000 mile oil changes and sample the oil at each oil change. I am looking at ordering kits for all my autos/trucks/and a motorcycle this November. My state has a 50% tax credit on the conversion costs for cng and lpg.
I did notice that you have some long hoses on the injectors. It will run better if you can shorten those up some.