351w build....
Thread Starter
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Street Queen to the extr3m3
Joined: Jan 2005
Posts: 4,554
Likes: 3
From: Lubbock, Texas
351w build....
Ive been getting this nagging itch to build a motor... for some reason or another i cant tell ya why. So i have decided that since im going to build one ill do it for my truck. I want a 351w probably stroked to maybe a 408. I would like to turbo it and maybe run it off of propane as well...
With that said. This is all just in paper stages.
I would like to hear some opinions on this.
I am no where near dead set on this... Just something ive been considering for awhile, any suggestions and opinions are greatly accepted.
With that said. This is all just in paper stages.
I would like to hear some opinions on this.
I am no where near dead set on this... Just something ive been considering for awhile, any suggestions and opinions are greatly accepted.
Thread Starter
|
Street Queen to the extr3m3
Joined: Jan 2005
Posts: 4,554
Likes: 3
From: Lubbock, Texas
well....
I have commenced this build....
not sure if i want 396 or 408....
Suggestions?
Also it will be getting 2 snails and maybe some giggly gas too...
lookin for suggestions and opinions here....
I have commenced this build....
not sure if i want 396 or 408....
Suggestions?
Also it will be getting 2 snails and maybe some giggly gas too...
lookin for suggestions and opinions here....
Tuned
Joined: Jun 2005
Posts: 288
Likes: 0
From: Okanagan
For my Propane conversion I had the heads shaved as far as I could to bump up the CR to around 10:1. Propane can handle up to 16:1 but I would suggest you go lower since propane isnt always pure and can give you problems with ignition.
Are you going with a draw through or blow through setup? Single or dual mixers? Im planning on a single OHG 450 blow through setup for simplicity of tuning. Adapting a mixer for boost is easy on a blow through setup. All that is needed is a balance tube connecting either side of the mixer so different pressures will not close the mixer valve. Im not sure exactley to tune on a dual or a draw through setup.
Im in the same boat you are, I need more information on turbo propane conversions. I hope someone knowledgeable can chime in here since the information is nowhere to be found online.
Are you going with a draw through or blow through setup? Single or dual mixers? Im planning on a single OHG 450 blow through setup for simplicity of tuning. Adapting a mixer for boost is easy on a blow through setup. All that is needed is a balance tube connecting either side of the mixer so different pressures will not close the mixer valve. Im not sure exactley to tune on a dual or a draw through setup.
Im in the same boat you are, I need more information on turbo propane conversions. I hope someone knowledgeable can chime in here since the information is nowhere to be found online.
Tuned
Joined: Jun 2005
Posts: 288
Likes: 0
From: Okanagan
It all depends on how much boost you plan on running to approx how much the CR will increase.
Increasing the compression ratio nets an increase of thermal efficiency of the burning fuel which increases power, but increases cylinder pressures and temperatures as well, causing preignition. Propane is great in this case since its nice and cold and is around 110 octane.
Increasing the boost gives a different mechanism of power by pushing more cool air through the engine. The air is already cooled through the intercooler, increasing its density and increasing CR. I found a chart off a lightning website that gives some examples.
Increasing the compression ratio nets an increase of thermal efficiency of the burning fuel which increases power, but increases cylinder pressures and temperatures as well, causing preignition. Propane is great in this case since its nice and cold and is around 110 octane.
Increasing the boost gives a different mechanism of power by pushing more cool air through the engine. The air is already cooled through the intercooler, increasing its density and increasing CR. I found a chart off a lightning website that gives some examples.
