What are the big differences between the 2? While deciding on a cam, this is a question I always wanted an answer for. Not just any answer, but an answer from someone who has ran both cams. I just thought I'd share my experience with both the VS vs the XP. The answer will be broken down into 4 sections. Based on the info in the sections, hopefully you can make a more educated decision.
Idle& streetability/ Gas Mileage/ Power/ Overall potential
This review is based strictly on my observations and opinions. The comparisons of the cams are assuming there are similar mods and tuning done to both.
IDLE:
You will hear the lope from both of these cams, and they are both easily tunable for daily driving by just raising the Idle a little. I prefer a lower Idle because both cams are still have decent street manners even with the idle set at 600-650. (and of course this is strictly a matter of opinion).
As far as sound, prepare yourselves folks: They sound almost the exact same. I think the pattern of the lope and the tone are identical; However, the XP is a little more defined.
The best way I can describe it is The XP sounds like it is a bigger cam without it being a louder cam. The lope of the VS goes(blum blum blum) The XP has a sharper, more defined lope (Plum Plum Plum Plum). Sorry about the stupid imitations, but until I get some comparison vids, that's the best I can do.
I would not have noticed the difference in sound if I hadn't tried to listen for one.
Gas Mileage:
I think I can say confidently, the VS cam gets better gas mileage (as it should being the smaller cam). I am getting the same gas mileage out of the XP as I did with my VS; However, The XP is being ran in a 9.4:1 Block with milled heads for an overall compression of 9.73:1 (same tune). The higher compression is most likely the reason the gas mileage is comparative. In an 8.5:1 compression block, I'm convinced I would see a small drop in MPG's with the XP. This is good news for the Top Swapped guys either way you slice it. XP setups on 9.4:1 can see similar gas mileage as a VS setup on 8.4:1. And a VS setup will be even better. (If tuned of course)
Power:
I've heard over and over the VS cam is comparative to rockers. I have 7 letters for that statement. R.O.F.L.M.A.O
The vs cam is a downright nasty street racer's cam that will leave 99% of the high ratio rocker guys in the dust!... Period. On the street, this cam packs more punch than the XP. And even while on the strip, I found that I run my quickest 1/4 miles shifting at 5800-6k. I can pull 1-3 MPH faster traps shifting at 6100-6200, but the ET is always the same or a little slower. This supports the theory thet the VS makes collosal torque in the Low and Mid RPM's. You can feel the car struggle to make power after around 6100
I've yet to go to the track with the XP, but I can tell already that the power band is moved to the higher end of the RPM's.
I have not shifted above 6k yet with the XP, but there is no doubt the cam is just ready to let all hell break lose after the Mid 5k range. The Vs cam is much snappier. With stock shift points and similar mods, I believe the Vs will pull an XP car mod for mod from anything less than a 50 roll all the way to 100mph or so, But the XP will not be far behind. On the highway... Vs has no chance against an XP (Mod for mod)
On the other hand; With raised shift points on both cams, I don't think the VS could outrun an XP car to 40MPH, And halfway through that Loooong second gear, The XP would open a family sized can of whoopass on the VS cammed car. The VS cam dumps all of it's power on you. The XP cam piles it on, then just keeps piling it on.... and piling it on some more
When you catch a WOT skip-shift, the VS cam feels like someone jumped in your lap. When you do the same with the XP cam, It feels more like an Obese person politely sits in your lap! This is the best analogy I have for the difference in feel.
Overall potential:
The Vs cam holds it's own against XP, S1X cars. As a matter of fact, with basic tuning, The Vs produces nearly the same ET's in the 1/4 mile as the bigger cams; However, the Vs cam generally does not produce as high trap speeds. This proves that the top end of an XP or S1X is much stronger than the VS, and the VS has a much stronger low end then the other cams. Usually by the end of the 1/4 mile, the bigger cams simply hadn't had enough road to show just gow much stronger the top end really is. This usually results in a fairly close race.
Numbers don't lie! The XP cam is comfortable making 340-400 WHP while the VS cam struggles to get beyond 350. So if you are going for maximum effort M90 fully built power, The XP is the clear choice. If your goals are very high 12's- very Low 13's without slicks (at close to sea level with good conditions), The VS cam is the cam that makes the most sence. It's cheaper to support, and it saves you more gas. The Vs is a good choice for those with stock valvetrain, but lets face it, there is only so much you can do with a stock valvetrain. I found out the hard way that upgrading the valvetrain components is almost a waste of money with the VS cam unless you have ported heads. Shifting at 5800-6K is not gonna kill a freshly replaced stock valvetrain. Yes upgrading makes a difference, but not enough to feel satisfied without extensive tuning or excellent exhaust flow.
My Advice:
If you want a hard core street machine that can put up a fair fight with the big boys from a stop until around 105mph, Get the VS cam. It's a good cam with decent gas mileage that can get you into the 12's on street tires with stock valve-springs and timing chain. No other blower cam will do that (reliably).
If your goal is more than that, and you like going to the track, or just want freakish post-100MPH highway power for a 3800 get The XP cam, it should make going fast a lot easier in the long run.
Originally Posted by mechguy
