Ford 460 on propane, what spark plug gap? - Pirate4x4.Com : 4x4 and Off-Road Forum

Mike2.5 · 06-18-2007, 03:21 PM

O.K., I tried searching but didnt come up with much. I have built a 460 I am planning to run on propane, I was told to run autolite AR32 plugs but I dont have a clue what to set the gaps at. The specs are,
.060 overbore 472 cubic inches
DOVE-C heads 2.19, 1.76 valves, smog bumps removed, some bowl blending
Comp 34-239-4 cam .554, .574 lift, 226, 234 @ .050
10.75:1 compression ratio
L&L headers
Stealth intake
Anyone know what I should set the gaps at? Please help!

mj · 06-18-2007, 07:38 PM

try .030
you didnt mention the ignition system at all in your specs
lpg like timing to come on real early

Mike2.5 · 06-19-2007, 04:07 PM

O.K. thanks, my ignition system will be a Holley anihilator with a Pro Comp hei distributor I bought of ebay.

jonnybronco · 06-21-2007, 02:24 PM

Mike,

If you don't mind me asking, what propane setup are you using? I am doing a similar build on a 429 and plan on using a single OHG 450. I am just curious, because I am afraid I may need to do dual mixers.

Jonny

Mike2.5 · 06-21-2007, 09:09 PM

Hey Jonny, I havent bought the propane setup yet. I have been looking at the 700 cfm Technocarb with dual vaporizers from propaneguy. I think Levigarret? here on the board is running the 450 OHG on a 460, maybe he will chime in with some input.
Mike

jonnybronco · 06-22-2007, 12:52 PM

I was originally planning on going dual OHG 450 or Impco 425 with a cam similar to what you have, until I found this whole setup for $100 from a local shop that use to do conversions.

I have since decided to go with a more conservative cam (RV type) to keep the RPMs where my single mixer can hopefully handle it.

I also considered the technocarb, but it was kind of pricey, but it should handle up to 5k+ RPMs nicely.

I have heard of some people running single OHG or Impco mixers on big blocks with success, but i still worry about it not being enough.

LeviGarrett76 · 06-22-2007, 03:51 PM

Im running .030 in mine!!! runs great..

I have a very similar build to you mike....edelbrock aluminum heads and a similar cam with 12.2:1 compression, edelbrock performer rpm intake...

Im running the OHG 450 and it will run to 5k just fine....but it needs about twice the air/fuel mixture its getting once you get over about 3700. To get all the power out of it i can i need at least 850 cfm to be able to run her to 5700 or so

Im still debating what to do...I hear single plane intakes work much better on propane carbed motors because there is no fuel to vaporize...its already vaporized once it reaches the intake....im thinking of trying something with dual ohg450's

reason i am dragging around on it is because For the wheeling i do i have all the power i need...and its rare i go over 3k rpm...but i always want my full power potential...SO...

Mike2.5 · 06-23-2007, 08:48 PM

Great! I will try .030. Thanks for the input!

06-18-2007, 03:21 PM	#1 (permalink)
Mike2.5 Wheeler Join Date: Apr 2007 Member # 89956 Location: K.Y. Posts: 254	Ford 460 on propane, what spark plug gap? O.K., I tried searching but didnt come up with much. I have built a 460 I am planning to run on propane, I was told to run autolite AR32 plugs but I dont have a clue what to set the gaps at. The specs are, .060 overbore 472 cubic inches DOVE-C heads 2.19, 1.76 valves, smog bumps removed, some bowl blending Comp 34-239-4 cam .554, .574 lift, 226, 234 @ .050 10.75:1 compression ratio L&L headers Stealth intake Anyone know what I should set the gaps at? Please help!

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

06-18-2007, 07:38 PM	#2 (permalink)
mj Registered User Join Date: Oct 2000 Member # 1919 Location: BC Canada Posts: 7,547	try .030 you didnt mention the ignition system at all in your specs lpg like timing to come on real early

06-19-2007, 04:07 PM	#3 (permalink)
Mike2.5 Wheeler Join Date: Apr 2007 Member # 89956 Location: K.Y. Posts: 254	O.K. thanks, my ignition system will be a Holley anihilator with a Pro Comp hei distributor I bought of ebay.

06-21-2007, 02:24 PM	#4 (permalink)
jonnybronco Registered User Join Date: Aug 2006 Member # 77280 Location: Yuma Arizona Posts: 22	Mike, If you don't mind me asking, what propane setup are you using? I am doing a similar build on a 429 and plan on using a single OHG 450. I am just curious, because I am afraid I may need to do dual mixers. Jonny

06-21-2007, 09:09 PM	#5 (permalink)
Mike2.5 Wheeler Join Date: Apr 2007 Member # 89956 Location: K.Y. Posts: 254	Hey Jonny, I havent bought the propane setup yet. I have been looking at the 700 cfm Technocarb with dual vaporizers from propaneguy. I think Levigarret? here on the board is running the 450 OHG on a 460, maybe he will chime in with some input. Mike

06-22-2007, 12:52 PM	#6 (permalink)
jonnybronco Registered User Join Date: Aug 2006 Member # 77280 Location: Yuma Arizona Posts: 22	I was originally planning on going dual OHG 450 or Impco 425 with a cam similar to what you have, until I found this whole setup for $100 from a local shop that use to do conversions. I have since decided to go with a more conservative cam (RV type) to keep the RPMs where my single mixer can hopefully handle it. I also considered the technocarb, but it was kind of pricey, but it should handle up to 5k+ RPMs nicely. I have heard of some people running single OHG or Impco mixers on big blocks with success, but i still worry about it not being enough.

06-22-2007, 03:51 PM	#7 (permalink)
LeviGarrett76 Registered User Join Date: Sep 2002 Member # 13654 Location: Ga Posts: 1,054	Im running .030 in mine!!! runs great.. I have a very similar build to you mike....edelbrock aluminum heads and a similar cam with 12.2:1 compression, edelbrock performer rpm intake... Im running the OHG 450 and it will run to 5k just fine....but it needs about twice the air/fuel mixture its getting once you get over about 3700. To get all the power out of it i can i need at least 850 cfm to be able to run her to 5700 or so Im still debating what to do...I hear single plane intakes work much better on propane carbed motors because there is no fuel to vaporize...its already vaporized once it reaches the intake....im thinking of trying something with dual ohg450's reason i am dragging around on it is because For the wheeling i do i have all the power i need...and its rare i go over 3k rpm...but i always want my full power potential...SO...

06-23-2007, 08:48 PM	#8 (permalink)
Mike2.5 Wheeler Join Date: Apr 2007 Member # 89956 Location: K.Y. Posts: 254	Great! I will try .030. Thanks for the input!