Author Topic: 4 7 and 4 7 2 3 swap cams  (Read 1440 times)

Offline wideopen231

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Re: 4 7 and 4 7 2 3 swap cams
« Reply #15 on: June 11, 2017, 01:09:36 PM »
So if swap cam is cheese burger the others are not worth having because no cheese? Burger w/o cheese is just money in trash can. Around my house cheese is food group and in most every meal .LOL
Relecting obama is like shooting right foot because it did not hurt enough when you shot left foot

Offline dreracecar

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Re: 4 7 and 4 7 2 3 swap cams
« Reply #16 on: June 11, 2017, 02:54:43 PM »
but if are lactosse intorerant, you dont need the cheeze in order to satisfy your hunger and it gets the job done

Offline masracingtd1167

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Re: 4 7 and 4 7 2 3 swap cams
« Reply #17 on: June 12, 2017, 02:12:36 AM »
You guys are making me hungry !

Offline ricardo1967

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Re: 4 7 and 4 7 2 3 swap cams
« Reply #18 on: June 12, 2017, 04:40:53 AM »
Like I said before,  if the swap made any significant gains and all the racer had to do was swap 2 wires, why would the cam grinder offer any other verson??? Isnt the purpose of a cam grinder is to make a better product.
Well Bruce, I have a different perspective here. They can charge extra $ for the 4-7 swap. Basically the same reason why McDonald's offers hamburgers and cheeseburgers.
Gosh, what have I done...  ::)
Bruce, Lactaid pills help!

Offline wideopen231

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Re: 4 7 and 4 7 2 3 swap cams
« Reply #19 on: June 12, 2017, 07:07:07 AM »
but if are lactosse intorerant, you dont need the cheeze in order to satisfy your hunger and it gets the job done


Good analogy and funny too.
Relecting obama is like shooting right foot because it did not hurt enough when you shot left foot

Offline coupemerc

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Re: 4 7 and 4 7 2 3 swap cams
« Reply #20 on: June 13, 2017, 04:26:07 PM »
The 4-7,2-3 switch (18726543) firing order is actually the same as the small block Fords if you look at the way Ford assigns their cylinder numbers.

From Dave Reher..."The order that we call the "4-7 switch" (1-8-7-3-6-5-4-2) has produced 5-8 more horsepower in our pro stock engines and was a well kept secret by racing teams for years."

Offline dusterdave173

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Re: 4 7 and 4 7 2 3 swap cams
« Reply #21 on: June 14, 2017, 03:20:47 AM »
Exactly my experience--like I said before big inch high RPM units seem to like it a little bit
most other applications not so much--
I have always had a fascination with fast cars at the expense of more normal character development

Offline dreracecar

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Re: 4 7 and 4 7 2 3 swap cams
« Reply #22 on: June 15, 2017, 04:24:00 PM »
I had lunch with Ed Iskindarian and asked him about the swap, Got a chuckle out of him

Offline ricardo1967

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Re: 4 7 and 4 7 2 3 swap cams
« Reply #23 on: June 15, 2017, 05:17:57 PM »
I had lunch with Ed Iskindarian and asked him about the swap, Got a chuckle out of him
C'mon Bruce, spill the beans man...

Offline dreracecar

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Re: 4 7 and 4 7 2 3 swap cams
« Reply #24 on: June 16, 2017, 08:31:01 AM »
They grind them on request, But not really a consistent gain to warrant a production.

  What he did say was that "Grumpy" had him make a few sets of roller lifters that the rollers were offset so he could adjust cam timing to each individual cyl just by swaping lifters.  I sumize that he had is cam grinder do a standard profile without letting him know what the true numbers were and having his secrets known

Offline Frontenginedragsters

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Re: 4 7 and 4 7 2 3 swap cams
« Reply #25 on: June 16, 2017, 07:50:27 PM »
It seems like in our industry whats new is really old just re-packaged.
Yes Ford did the same thing in 1969 when the 351W engine came out.
Ford changed the firing order to even things out.
The 4-7 swap was not used when I was a nitro crew guy but it became standard many years ago.
My two oldest sons work on Tim Wilkersons nitro F/C so I keep up thru them.
Now the 4-7-2-3 is the norm. It gave them a couple of extra runs on a crankshaft.
The guys to ask about HP would be the Pro-Stock or Comp guys as mentioned already.
I think for what most of us are doing the benefit would be not noticeable.

That's my offering.

Matt Shaff
Driving a Front Engine Dragster builds character and keeps you awake for a 1/4 mile at a time.
http://www.pro-formancespecialties.com/