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Old 01-22-2021, 10:34 AM   #223 (permalink)
Master EcoModder
Join Date: Oct 2009
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Very interesting data.

I had read of the prefired chamber.

This system seemed to mainly improve emissions but not MPG, based on the reports. Also this was 1973 I am fairly sure they could not met or beat the more strident standard emission later and not now.

I have also read the same kind of improvements were/are possible with computer controlled fuel injection. And again I do not think even those systems can pass now a days.

Diesels were embraced overseas until they found out they cause even worst pollution than gasoline cars due to NOX emissions and now they are talking about a total ban.

I also read the trick of helping vaporizing by allowing fuel to sit on the intake valve, the same claim for the 85 to 90s TPI system port injector system.

So the questions are would these engine beat the current emissions requirements??

I believe the much higher cost of making those heads stopped their manufacture if I remember correctly.

At the same time I am fairly sure the fix is in to keep MPG low and that cars like these Honda and other are held back and that they could make things better.

Which is one thing I have tried to do: To find a system that could be added to current cars, trucks and Vans as an aftermarket add on.

I worked with HHO, which did not work more than a couple of times, out of about 20 cars and tests.

I looked into Propane but the law changed so you had to buy it at gasoline prices as a motor fuel which removed any savings.

Other than special PCM tuning there seems to be no other systems that can make any major improvement other than 100% pure vaporizing of Gasoline.

And that is beyond any small shade tree mechanic to engineer.

I am left to build the best engine I can for my 93 Van.

I am using every bit of what I have learned and seen and read using known systems for the maximum miles per gallon I can.

My current quest is to make my 93 Chevy Custom Van to get better than 14MPG, I am working to get it over 20MPG and hope for near 30MPG…

I know that these MPGs will only be possible on level, windless highways at 65 to 85 MPH.

My old Mercury Grand Marques was able to get 30MPG at 65MPH but at higher speeds dropped to 24 MPG at needed another gear…the 30MPG was at 1700RPMs at 65MPH.

With American cars I have noted on a number of cars and a 02 Ford Explorer SUV that the best MPG happen at speeds at under 2000 MPH. And even then I have only seen near 30MPG.

So to have a BIG Van, a mini RV get near car MPGs will at lease allow me to enjoy taking trips and not feel bad about not taking a car.

The problem is this only works with engines that are not lugging, that are camed to handle the HP and Torque needed to pull a car/van at these low RPMs.

To do this I am building a low RPM high torque 383 and doing a number of High MPG changes/mods. This engine is built to have its base torque peak at 2000RPMs which will allow it to work at 1500RPMs.

There are a few other ideas I can use with an older OBD1 PCM like a lean burn system to run lean at cruse speeds, added EGR to farther help, by reducing NOX, offsetting incoming charge, and perhaps by helping overcoming pumping losses .

Along with this engine I am looking at changes to the drive line to best use this new engine, including transmission changes like to a newer 6 or 8 speed automatics, (Found to not be a good cost vs. benefits cost wise for me) rear end changes to lower rear end gear ratios, (impossible to get new gears below 2.73) and lastly adding a second over drive.

The second overdrive seems in my case to be the best idea. Sadly this is only true for me as I have a pair of older Borg Warner 3 Speeds with overdrives that were an add-on to three speeds and can with some effort devoiced and set up as a stand-alone Overdrive.

For everyone else the cost of a Gear Vendor system is in the range of $3000.00 to $5000.00 installed.

These old transmissions can still be found but they are running $500.00 to $1500.00 plus the cost of rigging them to be used only adds to the cost, which gets into the cost VA benefit area.

On the cost VS benefit area if I had not started this engine build 15 years ago I would not be a good deal now a days….not even sure it works now, and if my ideas do not work than it will not have been a good idea after all.

But one way or the other I need to save my major custom Van. So I am going for it.

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