What will an after market cam shaft do to the preformance of a V6. I have been told this will change the tone of the engine and the exhaust.

 

If done right with new springs & retainers, and with the right grind specs, you can pick up a couple dozen horsepower in the rpm range that the camshaft was designed for. By providing a bigger lift (valve opening) and duration (amount of time valve is open), you will draw more air/fuel into the cylinders, thus getting a bit deeper growl from the bigger combustion volume. Therefor, what you've heard is correct. However, the true attraction of a cam swap isn't the noise, but the power that you tailor to your needs in the rpm range. Want a motor that'll scream at high rpm's? Go with a big duration, high lift cam. Want better streetability and torque? Go with a moderate duration, but higher lift. Want to run higher compression pistons on pump gas? Look for a cam with more overlap. et cetera.

Camshaft selection is an art and a science, hence the reason there are typically so many different grinds available for each specific engine. The key is matching the cam to other modifications you have or are planning, and also to the intended use of the car.

 

Hey Thank you for your knowledge, from what you stated I should find a great mechanic for the job.

 

I would recommend picking a reputable cam company that offers various grinds for the 4.0L V6. Contact the cam companies' tech lines directly (skip the 3rd party vendors who only resell the products), and tell them what you've already modified on your car, what you plan to modify on your car, and how you intend to use your car, and they'll recommend the proper cam grind for your circumstances. This will save you wasted time and money, and prevent the frustration of picking the wrong cam for your combination (that may cost you power!).

 

I picked up 73 HP with heads and cams

 

on a 6 popper?

 

Yeah, I had the cams custom ground and the heads are ported and polshed.
When I had them installed after the blower I went from 297 to 381, and then I sold the blower I went down to 270 hp NA, that is up from a best of 197 NA

 

WOW!! You went to 270HP at the tire ranebowcyxx from the 4.0L? LOL! Thats good information! Man these 4.0's are impressive.

So your going to be doing real good with your new setup ranebowcyxx. You may see something real good with 8-9psi.

Its going to be interesting where you end up, once you hit the rollers.. That is very impressive ranebowcyxx.. 270RWHP normally aspirated! Your right there with the stock GT's no doubt!

Basically your 4.0L is producing 320HP at the flywheel N/A ranebowcyxx! Imagine if Ford marketed the 4.0L S197's at 320HP V6! They would sell like hotcakes! LOL!

 

Yeah I was very happy with those numbers. The down side to my setup right now is not enough back pressure so torque is low. I just got my 3500 stall put in and it really woke the car up down low. If I was staying NA I would change the exhaust to help with the torqu issue.

 

Thats really impressive. What kind of blower where you running?

 

I'm in between what mods for 4.0 I'm leaning towards the X charger, but if I can have a little blower whine I'd like to have nice lobing cams. where did you get all your work done? what cams did you go with and do you know who has any available. the X is going to run about 4300. did all your work cost less, right now I'm dyno'd 214 rwhp and 253rwtq, i figure the X should bring me up to 300rwhp... I have Jba hdrs, x pype and magnaflow dual. please give any info you wish to divulge. if I can pick up about 70 - 75 hp it would bring me up to 280 - 285 at the wheels, that would be great! I would seriously consider going that route.

 

lk[quote=mustangcr8z;if I cant have the blower whine I'd like to have some nice lobing cams, especially if I can pick up 70+hp

 

The gains in power from swapping a cam are maximized by adding a true dual exhaust and high-flow air filter. Seeing as the engine is just a big air pump, the easier it breathes the more power it can make. By opening up the intake (air cleaner) and the exhaust (duals) you can move more air thru the engine. If you really wanna spend some $$, a turbo or supercharger (forced induction) crams even more air into the engine to make more power.