4 to 7 is it worth it?

[tarheelsoldier]

I am having LE grind me a cam. But since it's going to be custom, should I have the 4 and 7 cylinder swapped? Or is it even worth the hassle?

[BIG CAT]

imo waste of money for all but the most radical combinations. you can make plenty of power and be reliable with a std setup.

[joelster]

I have the 4/7 swap. I did lots of research before I did it. I never saw a single example where it LOST any power over the traditional firing order, and quite a few examples where it made a tiny bit more power way up top. It usually made the same power, but around 6500+rpm it would pick up a few ponies. If it doesn't cost you any more money I don't see how you could do any harm.

[NightTrain66]

if you are already buying a nice $400 billet cam the 4/7 swap is probably the same price or maybe a $30-50 increase in price, sure why not. Especially on a carbed set up when you just re rout 2 plug wires. Fuel injection makes it a lil tougher but no big deal.

I sell custom cast LT1 cams for $300 shipped or a billet LT1 cam for $375 shipped or with 4/7 swap for $400 shipped (no cast LT1 core with 4/7 swap). I would say most people are better off spending that extra $100 on a better stall converter, better headers, better tuning, better suspension drag shocks/springs).

I know bracket racers that have had cars together for years and went back with the same cam specs but 4/7 swap in their 550-650 HP SB and 650-750 HP BB and only mention .002/.003 of an ET difference. They mention it "might" be a smoother running engine (easier on bearings) but they also agree that might be all in their head and just placebo effect (sugar pill).

Most mag articles that do the swap are also changing cam specs, valve spring pressure, more tuning or some other change that can usually be attributed to the large gains found in the article.

I am sure that in some racing where you can moniter results better about what is going on inside the intake manifold and what Exhaust Gas Temp is in every cylinder, tweak firing order/cam specs on cylinders and retest, again, again, again, again and again (NASCAR, PRO Stock, other "class" cacing) there is some gain to be had. Probably diff. cam specs for different cylinders as well as swapping firing orders. The average person that reads a Hot Rod or Car Craft article and does a 4/7 swap (instaed of doing all of the above mentioned R&D) expecting a 10+ HP/TQ increase will be disapointed or enjoys the sugar pill and is happy with the results.

Lloyd

[Soxxpuppet]

Very well said Lloyd. I doubt itll be worth much, if anything. Stick to spending the time and money on something more usable and rock solid.

[tarheelsoldier]

Yeah that's what I figured out and after reading this, I am not gonna do it. I will spend that 100 helping get some better headers. And duals. Granted for that it won't go far, but still it's a start. Lol

[NightTrain66]

good idea,

not that the $100 would actually buy headers, stall, suspension parts, etc but that could be added to and put towards the $$$ you wrre gonna spend on those parts and get better ones.

Lloyd