Towing Power?

[schiker]

Be careful comparing heath's land speed record truck to a tow vehicle. Or comparing one strategy build to another.

You get a whole lot more underhood air flushing the engine compartment running 100 mph vs crawling up a grade at 30 mph or less. Heat soaked compartment environment and open element can easily derate the engine. If you can maintain 45 mph would be an improvement of air flush over 30 and might make all the difference and or 10 degrees ambient might also make a significant difference comparing one pull to another.

I think there are a lot of other nuiances to Heaths build that are a bit tougher to pick up on. As far as it being the fastest 6.5 I have read of other powerful builds maybe not quite as fast but great builds. Not taking away from Heath at all Heath knows his stuff and has different tricks up his sleeve for different applications and desired outcomes.

Cooler air is almost always better. But too cool might be something overlooked. Interesting reading tidbit Turbine Doc has dropped mentioning optimal IAT at 150F ish in a few posts. The temperature of air in the cylinder does have an affect on the penetration rate of the flame front of injection spray (why there is cold advance timing and why different thermostats offer different performance).

The 6.5 is a simple idi engine yes but when you start trying to eek out the very best performance its a long long discussion and total system thing. Somethings build well on each other some don't. Make sure you know how each tweak or mod affects others and overall system.

And I agree it might take a week and 1000's of typed words to explain all the interactions of just a handful of mods. I am still reading and learning.

 

[JiFaire]

I really feel the need to post a strong caveat here...

WARNING:

Propane fumigation is NOT good for an IDI engine, without modification of the pressures and volumes released that is closely correlated to the fueling curve.

Yes, MaxxTorque has an article about using propane in a 6.5 to generate 303 hp - that's Ian Carver's truck. I didn't read about it... I actually KNOW Ian, and have seen the truck. He also ran nitrous, which tends to dampen the event spikes caused by propane, and the kit and engine were both heavily modified to make it all work... more than anything else, getting power (or improving cooling, or improving reliability, etc) the 6.5 is a matter of synergy... doing a bunch of the right things in the right amounts to make the total add up. There just IS no magic bullet with this engine.

Others (LOTS of others) have tried to run either the Bully-Dog kit or the Powershot 2000 kit with the 6.5, and had less-than-stellar results... these two kits are the industry standard, and if THEY can't get a good solution to the problems with IDI engines, I doubt you're going to see much from your average ebay seller.

I talked with Bill Heath about propane once, and he said there was too many problems with it to make it a workable solution at that time, although he had some ideas he wanted to try. At the time, Ian completely agreed, and even went so far as to post a strong warning against propane on the other forum.

I can tell you with 100% conviction that if you add propane to a 6.5 you can kiss your motor goodby. It will make big power while your pistons and rods stay together but it will make short work of your entire rotating assembly. Propane detonates at a much lower temp than what that piston is making at TDC, aka predetonation on every stroke.

I ran a PS2000 kit a few years back. I did a ton of research and finally made the leap. I wanted it for a little added power for towing on the hills. It did not work out at all, I found when I was towing it would ping bad under load so I had to keep dialing it back to ease the pre-detonation, to the point where I got absolutely no added power from it. Maybe timing could have helped, but I can't be under the hood timing it every time I want to adjust the propane, or run out.
When unloaded it was great, I could really feel a difference in power. But certainly no way to save money. On top of the cost of the kit, I was paying for a fillup of propane every couple weeks or so, and using more fuel hotrodding around.
The benefits of a propane injection kit can't be fully realized on a 6.5 anyway because of the indirect injection. Much more suited to a direct injection engine. Plus, it did make me a tad nervous having it onboard.

Propane works VERY well on a direct-injected engine... Duramaxes, Cummins, and Powerstrokes all like the stuff, as it adds power and keeps EGTs down.

In an IDI engine, it's a shortcut to piston damage. That's why it earned the nickname 'Pane ...

That's just the way it is, with the current technology... I would really be remiss by not pointing this all out; but if you want to give it a shot, have at 'er... please post pics and details, 'cause if you figure out how to make it work without the big KA-BOOM that usually accompanies experiments with Propane on a 6.5TD, we'll all buy your kit.

Entrepeneurs are the guys who do things that conventional wisdom says can't be done... good luck!

 

[buddy]

OK, I didnt think it was that bad, since Heath does sell propane injection in a kit. I was planning to use water with it coincidentally, but maybe that is the key for having it work reliably. The ignition point of propane is like 800F, so I thought that was a high enough temp to prevent pre-detonation, since its almost twice that of diesel.

 

[JiFaire]

Last I heard, Bill was working on a kit that would limit the propane to safe levels; something that would let the propane be mixed in proper ratios depending on the engine telemetry. I know Ian was excited about it, but still haven't seen the final product.

Using water injection might be a good way to go about it; I haven't seen a 6.5TD running both (we only see water injection for about 6 months a year up here j/k)

A friend of mine has propane in his Cummins and it's just NUTS how much scoot that truck has, but most of the people I know who have tried it in a 6.5 have had problems. I sure hope Bill (or you) come up with a good solution... Preferably something that works with, but doesn't require, water injection. Propane would be a a great supplementary fuel for us guys up here near the glaciers.

 

[buddy]

Heath mentions propane injection in his performance combo kits

 

[buddy]

Where do you find a concise data/fact sheet on the ATT and where to purchase it?

I'm looking at all the propane info again, and it should work fine, especially in low concentrations, since it isnt initially combustable if under 2.5% mix with air and doesnt autoignite until over 800F. Since our engines use such a lean mix, little air to begin with if someone put in a large shot of propane could have been like 10% mix might explode With water injection I can probably increase the concentration. I'll start that project after characterizing these different chips. Anything for a tax break right (hybrid vehicle)

If it breaks the engine I'll either get one of those diesel depot 6.2L bored over .04 and the 18:1 ratio or wait until GM comes out with the 4.5L DMax and 'pane it.