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Author Topic:   firing order
30rulz
Member
posted January 12, 2004 06:50 PM
I've seen somewhere that you can change the firing order on a sbc for racing applications I think you change 2-7 wires around has anyone tried this?


dan ferry
Member
posted January 12, 2004 07:18 PM
havent heard of that i have in ford cams but who knows


Scott1975
Member
posted January 12, 2004 07:27 PM
I think it is only fords, I think it was 3&7 or something like that.Don't really remember, it's supposed to make a quicker throttle response on the 302's and 351W, but dont hold me to it.


NWModracer
Member
posted January 12, 2004 09:37 PM
yeah its the 4-7 swap on a chevy but if you run IMCA it was outlawed for 2004


dirtracer7
Member
posted January 13, 2004 12:43 PM
351w ,302 h.o. have a different firing order than a standsrd 302.It depends on who you ask about it as to which is better.I was running the 302 firing order last 3 years and am trying a different cam with 351 firing order.Some say 302 f.o. will produce more torque but just about all cam mfg. say to run the 351 f.o. because it loads the motor more equally.As far as your Chevies go I don't know ,other than the comp cams changed firing order.They say it has an extremely smooth torque curve and less crank deflection.

[This message has been edited by dirtracer7 (edited January 13, 2004).]

outlawstock17
Member
posted January 13, 2004 05:05 PM
that's right dirtracer7......ford changed the firing order from 15426378 to 13726548 because having #1 and #5 fire sequentially loads the front main bearing. other than that, i don't think there is a power advantage either way. i've ran them both ways and couldn't tell any difference.


stockcar5
Member
posted January 13, 2004 07:41 PM
gm changed the firing order on their gen 3 small blocks to 18726543. they claim it runs smoother and extends engine life.
dont know if it helps power at all. i would say no.

luke

30rulz
Member
posted January 14, 2004 09:52 PM
I found where I've seen the other firing orders. go to the mr. gasket web page in the online catalog in the section that has the cams it lists 2 different ones 18726543 and 18736542


zeroracing
Member
posted January 14, 2004 10:30 PM
I have 3.330 6.125 30 over 400 block
i added the cam and got 36 more ponys and it pulls forever curve is great .pluss fuel ratio is much better


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