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when they say even fire/ odd fire when talking about 4.3 chevy 6v what does that mean? how can i tell which motor i have? how can i tell which distributer is even / odd ?

somebody help explain this to me.....

thanks
 

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Not true. The buicks have odd and even-fire v-6's, and chevy has even and semi-even fire v-6's. The early 200 and 229 chevy engines were semi-even fire, and all 4.3's are even-fire. Aftermarket cranks are usually odd-fire. The semi-even fire uses an 18 degree pin offset and 108-132 degree firing sequence, and the even-fire uses a 180 degree firing sequence like the v-8's. You have to use a even-fire dist., crank, and cam together, and likewise for the semi engines. A 229 dist. will run a 4.3, but not for long.:D
 

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kbud said:
Not true. The buicks have odd and even-fire v-6's, and chevy has even and semi-even fire v-6's. The early 200 and 229 chevy engines were semi-even fire, and all 4.3's are even-fire. Aftermarket cranks are usually odd-fire. The semi-even fire uses an 18 degree pin offset and 108-132 degree firing sequence, and the even-fire uses a 180 degree firing sequence like the v-8's. You have to use a even-fire dist., crank, and cam together, and likewise for the semi engines. A 229 dist. will run a 4.3, but not for long.:D
Not all 4.3 are even fire. All the high HP race blocks are odd-fire.

Here's a good site to explain what even and odd fire mean:
http://www.chitownsyty.com/tech/odd.htm

Odd fire race 4.3 end of page: http://www.tobefast.com/sytyengines.htm

http://www.strokerkits.com/4_3_chevy_v6.htm
 

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odd fire is more bitchen camo you need a new crank for your little motor. The reason for odd fire is you can make a stronger lighter more rigid crank. The other benefit is it sounds cool at idle got that uneven rumble that kind of reminds me of a harley. You need a turbo too BTW.
 

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Gordon said:
odd fire is more bitchen camo you need a new crank for your little motor. The reason for odd fire is you can make a stronger lighter more rigid crank. The other benefit is it sounds cool at idle got that uneven rumble that kind of reminds me of a harley. You need a turbo too BTW.

Stop giving him ideas :flipoff2: :flipoff2:
 

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Also if I’m correct all odd fire motors are externally balanced and use an 50lb+ flywheel.
 

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rubiconray said:
Also if I’m correct all odd fire motors are externally balanced and use an 50lb+ flywheel.

All the 225/231 Buick odd fire V6's did. I had a '70CJ5 with the
225V6 and that 50lb flywheel sure made stalling the motor a
hard thing to do. :D
 

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SanDiegoCJ said:

225V6 and that 50lb flywheel sure made stalling the motor a
hard thing to do. :D

Same with the 225 in my 53' m38a

Rich
 

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so what does odd fire mean? misses a beat? fiers down one side of the block then up the othr?
 

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Even fire V6's fire every 120° of crankshaft rotation. That is 120° - 240° - 360° - 480° - 600° - 720°

Buick odd-fire V6's fire at 90° - 150° increments. They fire at 90° - 240° - 330° - 480° - 570° - 720°. The reason is because the rod journals are evenly offset at 120°. The even journal offset is the main reason these engine's low end torque is so good.
 
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