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Author Topic:   4 and 7 swap
posted October 19, 2004 05:06 PM
Has anyone ever dynoed one of the 4/7 swap cams (besides the company saying there good) Just looking to see if they are that good and does the crank have to be turned any different...


posted October 19, 2004 07:46 PM
it gives u more torque and the only thing u have to do is switch the 4 and 7 spark plug wires around

posted October 19, 2004 08:17 PM
If there is no difference howcome some places are outlawing them? I've been told by a couple of engine builders that they are just a lot smoooother,kinda like built in traction control don't know otherwise.

posted October 20, 2004 06:32 AM
If the officials don't understand something they normally outlaw it.

Ego Racing
posted October 20, 2004 09:05 AM
Not really a HP difference but the engine dose run smoother. The power and torque don,t move enough to say it did anything but the verdict is out on longevity. We have on that is a little over 1 season old without anything but normal freshening with rings and bearings. The motor was at its limit and the crank is 30 under so we but it together to see how long it lived. Like I said a little over 1 season old about 1900 laps(at the track for racing and practice about 38 nites a year and about 45 laps a night). On alcky with a 4bbl.

posted October 20, 2004 02:18 PM
the cam company i use told me that it doesn't make anymore power unless your over 6-700hp and it only makes about 5 hp difference so it was not worth the swap or the time and money to do the job
but longevity i haven't heard that one new one on me...
some cam companies make a huge deal about the 4-7 swap (in my opinion to sell more cams) but on the dyno it doesn't make a difference
but if your using one in a claimer motor it would confuse anyone that claimed it GOOD JOKE on the jerk that claimed you LOL

posted October 20, 2004 04:43 PM
I have read where some claim the only real benefit of the 4 & 7 swap cams are for Drag racing. Supposedly it adds durabilty to the cranks because the loads drag cars are under on launch.

Seems like there would be a little gain in durabilty on dirt oval cars as well, but it may be small.

posted October 21, 2004 06:44 AM
Great input guys thats what I wanted

posted October 30, 2004 11:05 AM
On sbc or what ever short block you guys use after 1000-1200 hp. you get a benefit from this cams firing order because of main load displacement .With agood dry sump oil system. Depending on engine cid, compression fuel, you could gain as much as 20-30 hp. You need to weigh the price .

posted November 02, 2004 08:27 PM
well on the wheel dyno it is increase in power and the curve is great the thing that is real great is the fuel burn the o2 sen. is right on and all the wat thru the run
it just spreads the the timing of the fire so you dont have lean cyl. i gained the 30 ponys and then some it pulled my rpms with sme carb up almost 500 rpm dont know why but i am leaning to the fuel specialy on limited carb that is what the dyno and on track told me not cam builder the cost is hi
but if you are looking for the little edge worth it