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View Full Version : Restarting Injection Line heater thread



moorerp
29th November 2006, 03:21 PM
Hi All,

I'd like to reopen the discussion on using injection line heaters, but focused on how it's done by the do-it-yourselfer, rather than focused on whether it's a good idea or not.

I like the idea, and I'd like to do it myself because it seems fairly simple. So for any of you electrically savvy types out there who may have done it, how does one calculate the required length of nichrome wire to reach a target temperature? Calculating the resistance and amperage of a length of wire seems fairly easy, but how do these figures translate into max temperature of the wire?

Any other details concerning how you you wired your heaters and the materials you used would be much appreciated as well.

thanks,
Randall in bloody depressing Oregon, USA winter

Vegiecars
29th November 2006, 04:22 PM
Hi Randall,

in one of my earlier prototypes we were able to calculate how long the wire needed to be to reach a desired maximum temperature (with help from a university electronics lecturer). The problem was that it took a long time to reach this maximum.

The Fattywagons line heaters were not long enough, and as a result I measured temperatures in excess of 180 deg C on their product.

This is why our heating elements are thermostatically controlled, allowing a fast heat up time but only to a chosen maximum temperature.

Regards
Marcus

wvodasher
30th November 2006, 11:16 AM
The wire used in fattywagans heaters was 316 stainless steel 30 inches long, 76.20 centimeters long. .031 inches dia for 80 watt heaters, .035 inches dia for 100 watt heaters.
he provided this info on another forumm after he stopped making them.
hope this helps
later mark

Gen-Erix
24th February 2007, 02:14 PM
Hello, Im in Hawaii where the temp never falls below 60F (15C). Im planning to get a old Mercedes 300 and outfitting it with injector heaters and a fuel filter heater. Im eager to learn but am still learning about the process so talk slow and simple from time to time. So far I have found this info:


The nichrome wire used in fattywagans heaters was 316 stainless steel 30 inches long, 76.20 centimeters long. .031 inches dia for 80 watt heaters, .035 inches dia for 100 watt heaters.


1. I want it to function at 200F (93C) which seems to be a good temperature. What would I do to make it stay at 200F instead of going up to 2000F (1093C) Fuse, Temp Regulator, Thermistor?

BUT...
Quote: "the acrevo study does recommend 302F (150C) for canola oil for it to atomize similar to petro"


2. Ive seen kits that were already insulated with some sort of wrap. What is that?


3. What about injector lines cracking?
(at 150deg C, the issue I have is that the existing fuel lines are not manufactured for such extremes and, such rapid heating (and cooling) could lead (and has with some) to the fuel lines cracking.)


4. What about a second battery for the heaters?
How would I wire that up? Especially if I do some minor audio improvements as well.

Vegiecars
24th February 2007, 03:17 PM
see the "Anyone using injector line heaters" thread

moorerp
27th February 2007, 12:03 PM
[quote=Gen-Erix;12370]


1. I want it to function at 200F (93C) which seems to be a good temperature. What would I do to make it stay at 200F instead of going up to 2000F (1093C) Fuse, Temp Regulator, Thermistor?

BUT...
Quote: "the acrevo study does recommend 302F (150C) for canola oil for it to atomize similar to petro"

I've seen people talk about doing it two ways, on eis to put a temperature sensitive switch just downstream of the wire wrapped portion of the injection line, one that gets thrown at around 290 degrees F. It acts as a circuit breaker when the desired temperature is reached and will cycle the system on and off as the temperature of the oil in the lines falls and rises around the target temp.

I've seen other folks suggest doing much the same thing with a temperature probe which they monitor while driving. Then the driver can interrupt the circuit with a manual switch when the target temp is reached.


2. Ive seen kits that were already insulated with some sort of wrap. What is that?

Check McMaster Carr, if it's some kind of high temp insulative tape, they probably have it.


[quote]

Fattyman
1st March 2007, 01:22 PM
Fattywagons is back!:D