What makes the 'Low Rumble' of older cars?
03-03-2009, 04:48 PM
#21
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03-03-2009, 10:05 PM
#22
Actually, there are cams out there specifically for changing firing order.
Lunati and Crane make 4/7 swap cams.
You do not have to change the crank as the phasing of piston strokes remain the same.
As for the spark plugs, all you have to do is swap the wire from one plug over to the other and vice versa.
And if you are doing it on a port injection FI setup, you just swap wires from the two injectors.
Lunati and Crane make 4/7 swap cams.
You do not have to change the crank as the phasing of piston strokes remain the same.
As for the spark plugs, all you have to do is swap the wire from one plug over to the other and vice versa.
And if you are doing it on a port injection FI setup, you just swap wires from the two injectors.
so why would you want to change firing order? ive never heard of this before, dont mean to jack the thread.
And true duals sound so much better than a Y-pipe setup.
03-04-2009, 12:27 AM
#25
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the only problem with comparing firing orders between ford and chevy is that ford numbers their cylinders differently when compared with chevy and dodge
lets pretend that ford numbered their cylinders the same as chevy then their firing orders would be
4.6: 2-6-5-4-3-1-8-7
302: 2-1-8-4-3-6-5-7
im not sure where the myth originated that the 4.6 and the ls1 had the same firing order but they most certainly do not. im not saying you said that their firing orders were the same but i saw it a few posts up and felt the need to break that myth
lets pretend that ford numbered their cylinders the same as chevy then their firing orders would be
4.6: 2-6-5-4-3-1-8-7
302: 2-1-8-4-3-6-5-7
im not sure where the myth originated that the 4.6 and the ls1 had the same firing order but they most certainly do not. im not saying you said that their firing orders were the same but i saw it a few posts up and felt the need to break that myth
what you get is 4.6: 1-8-7-2-6-5-4-3
302: 1-8-4-3-6-5-7-2 look familiar?
looks like the firing order is the same so im here to correct myself
Last edited by 1994Z28Lt1; 03-04-2009 at 12:54 AM.
03-04-2009, 01:01 AM
#26
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Mufflers and H pipe go a long way toward sound on these cars. I have a dumped H pipe with full size dynomax mufflers and it makes my -4 degree overlap cam actually lope. Sounds amazing!
03-04-2009, 07:57 AM
#28
http://www.rehermorrison.com/Did you know that most Pro Stock engines use a different firing order than a standard V8? We swap the #7 and #4 cylinders in the firing order to eliminate the fuel distribution and heat problems caused by cylinders #5 and #7 firing in succession. With the Big Stick cam’s revised firing order, the two end cylinders do not have to "fight" for fuel from the manifold plenum. The result is a measurable power increase (typically 8 to 10 horsepower) and a smoother, cooler running engine.Reher-Morrison Custom & Big Stick 7/4 Swap Camshafts
Big Stick cams are ground on a custom core with the lobes repositioned for the non-standard firing order. If you’re looking for the last bit of horsepower, you should carry a Big Stick!
Last edited by SOMbitch; 03-04-2009 at 08:03 AM.
03-04-2009, 03:40 PM
#30
Yes, firing order makes a huge difference and the LS1 is different than old small blocks. But, that is why I listed cam. Cam determines firing order. You can't change firing order without changing the cam. Semantics, really.
Needless to say, that is why Ford V8's sound so nice. 5/7 swap.
Also, number of cylinders on a bank effect it too.
Odd numbers sound raspy, where even numbers sound lower. Take, for instance, a V10 vs. a V8 or a V8 vs. a V6. You get the idea.
I guess what I'm basically getting at is there are many factors that effect exhaust note.
Needless to say, that is why Ford V8's sound so nice. 5/7 swap.
Also, number of cylinders on a bank effect it too.
Odd numbers sound raspy, where even numbers sound lower. Take, for instance, a V10 vs. a V8 or a V8 vs. a V6. You get the idea.
I guess what I'm basically getting at is there are many factors that effect exhaust note.
03-04-2009, 06:18 PM
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03-05-2009, 09:39 AM
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You're telling me I can walk out to my car, rearrange the wiring and have a whole different firing order? (Assuming I know what I'm doing)
That's ******* weird.
03-05-2009, 09:41 AM
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seriously, if your dumb enough to do it... let the carnage commence
03-05-2009, 09:55 AM
#39
I guess you might say something like that if you only worked on LS1's where you can't easily put a plug wire in the wrong spot. But to anyone who has done it on something with a distributor, big flaming backfires out the carb that make the neighbors call the police tell me that the cam companies aren't making these special cams for nothing.
03-05-2009, 10:08 AM
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But based on your recent answer, I'd say it's not correct: the wires don't determine the firing order.