V8-Ranger.com

It's been too quiet on here, figured I'd post something...

the place does go quiet sometimes. Too cold to go outside, hate even walking down to the mailbox. Been collecting all my parts for projects in a central location in spare room in basement. Got a bunch.
Dave

I've just been working so much. Haven't had much time to do anything on anything. Haven't even been home but a few days in the last 3 months.

Same for me really, except the gone for three months thing. Been mostly working on finishing our basement, aka my section of the house.

I've been having fun getting the new 331 dialed in. It's running pretty well right now. There's a few rough edges still to be caught on a datalog and solved. But for the most part, it's settling in as a nice upgrade to the stock 302 I replaced it with. First gear is noticeably more powerful. 1/2 throttle breaks the tires loose with ease. Second gear is stronger than it used to be, but it doesn't break them loose like I was kinda hoping it would. But it's still impressive none-the-less.

Glad to hear the 331 is up and running. You never did build it for power though right? wasn't it a good gas mileage build. What kind of mileage are you getting? How long till it flips over to propane? Speaking of alternative fuels I saw one running on coffee this morning lol. Let me find the link quick. Here

http://newsfeed.time.com/2013/03/18/cof ... ?hpt=hp_t3

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.

I would have expected the 331 to use more fuel than the 302 but I must say you did a good job of keeping it close to the 302 in mpg.

Does your ECU have a spark table just for idle? or is it also referenced in low load part throttle driving? I experienced something similar on the Cobra which going to a large mono blade TB. It doesn't seal nearly as well as the factory round butterfly style and also causes a high idle due to the excess air getting by. I had to adjust the "idle air integrator" in the tune which tells the ECU how much air it's dealing with at idle and that brought the idle down some. To get the remainder of the way down I had to pull timing from idle. A lot. I think I have it close to 0 degrees actually (haven't looked at the tune since fall of last year).
The issue with that is when I pull off as soon as you touch the gas pedal it switches timing tables and the timing jumps from 0 straight to around 30ish I think it was and the rpms sort of ramp quickly and then blend in proportion to the amount you press on the gas. My thoughts are to go into the low load/rpm timing tables and lower the timing at the start of the table so it ramps in smoothly and makes a nice transition instead of the instant jump.

The propane tank install sounds like quite a job but also sounds like you're getting close. Very curious to see how that works out.

MalcolmV8 wrote:I would have expected the 331 to use more fuel than the 302 but I must say you did a good job of keeping it close to the 302 in mpg...

There's theory and practice. And after putting my theories into practice, I can honestly say if I had it to do over again, I wouldn't have done a 331. I would've gone with a 347 and a slightly more aggressive cam. But now that the 331 is in, it's not going anywhere unless something happens that forces the issue.

MalcolmV8 wrote:...Does your ECU have a spark table just for idle? or is it also referenced in low load part throttle driving?...

With my EEC, spark is defined from tables for part throttle conditions. However at idle, it uses idle spark functions.

MalcolmV8 wrote:...I experienced something similar on the Cobra which going to a large mono blade TB. It doesn't seal nearly as well as the factory round butterfly style and also causes a high idle due to the excess air getting by. I had to adjust the "idle air integrator" in the tune which tells the ECU how much air it's dealing with at idle and that brought the idle down some...

My EEC doesn't have an idle integrator control. My EEC has a Closed Throttle airflow scalar. Adjusting idle via either of these only affects idle speed when the ISC needs to be commanded to flow less air. In my case, the ISC is fully closed and the throttle body bypasses enough air to idle the engine at 700 RPMs. I can unplug the ISC and there's no change in RPMs. The only way to get lower idle RPMs is to lower the throttle plate position OR drop the spark. I can't lower the throttle plate because it sticks when set lower. And as stated above, if I can get a higher RPM with the same airflow, then I'd rather have that than inefficiently idle a lower RPM but burning the same amount of fuel.

MalcolmV8 wrote:...The propane tank install sounds like quite a job but also sounds like you're getting close. Very curious to see how that works out.

CNG, not Propane. Propane tanks and NatGas tanks are very different. Propane compresses and condenses into a liquid like any common AC refrigerant. A full tank only has 175PSI@100F. At freezing temps, that same tank would only have 55PSI pressure. NatGas doesn't condense when compressed to CNG. It's still a gas. But to get enough NatGas into a tank to be practical to use as a transportation fuel, the pressure has to be in the 3000-3600PSI range. The tank will fit between the fender wells and the back bed wall...similar to a truck tool box. A tank that size would hold 30 gallons of gasoline easy. But filled with CNG, it's closer to 12 gasoline-gallon-equivalent of NatGas.

Since what comes into my house is NatGas, that's all that will ever go into this system, although the regulators, line, injectors, etc should be capable of running Propane as well as NatGas. But I've been told not to ever put Propane into a NatGas tank. Although I haven't had anybody able to tell me why...just don't. Very helpful. An acceptable answer would be the liquid Propane might dissolve the epoxy that holds my composite NatGas tank together. But I seriously doubt Propane would dissolve something that NatGas wouldn't.

I was going to guess "O" rings or such. My Parker book must list 300 different gases and fluids and their compatiblity with different "O" rings material. CNG not there, propane yes. Probably something like Malcolm ran into with those gas hoses awhile back. You dealing with a tank with over 3000 psi of a gas, be very carefare, don't second guess. Many years designing pressure vessels, big and small.
Dave

I'm far less concerned about the tank. CNG tanks are tested in some VERY brutal conditions including being dropped off buildings and being fired at with rifle rounds. When they fail, they are designed to fail gracefully, not explode with shrapnel everywhere. It's the hard line I'm far more concerned about. Once the gas is leaving the tank, it's traveling through a 6mm ID tube with only a plastic sheath to protect it. So I've got to route that tubing in a way that it won't be bumped, banged, snagged, or crushed.

I got some more of the CNG equipment installed on the truck this weekend. I hoped to get it all done, but I ran out of time. But less and less is left to get done. Here's the pictures:
CNG conversion project Update

Love the pics. Keep em coming Anxious to see this fire and run and get your feed back on it all.

MalcolmV8 wrote:Love the pics. Keep em coming Anxious to see this fire and run and get your feed back on it all.

Chris would probably wish you would use another word than fire. Chris always comes up with something to work on. Keep up the work!
Dave

lol indeed. I'm curious to see it start up and run If you see fire run like hell.