Thread: s1x or xp?

s1x is faster..... so i vote that one.

Lol

330+ whp is attainable non-intercooled on e85 with both with a decent combo of supporting mods. Ive tuned quite a few S1X and XP setups and neither is a clear "winner" to me.

HP and torque curve with both cams will look very very similar. There were some hard numbers put together by Ron Vogal almost proving that one cam was better with X gearing while the other was better with Y gearing because of different factors like where you end up after the shifts (among other things).

That being said... if you gave me two cars with all of the exact same parts except the cams were different nobody would be able to tell which is which unless they are jesus.

If you want to do ported heads you always have the option of getting them flow benched and having someone like Paul at PRJperformance.com spec you out a custom cam that is designed for your heads and setup.

Ok now that where on the topic, what cam should I run with stock heads, mods to be are a 3.4, headers, cai, tune from I dont know where? oh 97 gtp

Both can be ran on stock heads.

ok do I need new valve springs or can I just put it in and go?

Id get 130# springs and modified retainers. Preferably a double roller timing chain also.

Ok then ill be good to go?

Honestly if your asking that...I don't think cam is the route to take just yet.

I know I still have alot to learn, Just trying to fill my head with info

Originally Posted by matt5112

whoa 130s? Where do you want to rev? The moon?

105's and a stock timing chain is more than adequate for either of these cams.

But if you do decide to get 130's, a double roller would be a good idea. Just know a lot of work goes with a double roller (machine oil pump cover, machined crank gear).

I have been running a single chain, s1x, stock heads, and #105's for over 10k miles without any issues so far.

Originally Posted by matt5112

whoa 130s? Where do you want to rev? The moon?

105's and a stock timing chain is more than adequate for either of these cams.

But if you do decide to get 130's, a double roller would be a good idea. Just know a lot of work goes with a double roller (machine oil pump cover, machined crank gear).

what if i DO want to rev to the moon? do i get 130's and the double roller chain?

Cams like the Thrasher and IS4 are cams high RPM driven...or Turbo cams for that matter also...you'll see 6500+ RPM Shifts no problem with the supporting valvetrain.

Um... 130# springs are an ideal choice for any cam besides baby cams. Both the S1X and XP rev upwards of 6200rpm where the recommended shift points are. XP cam has been said to have a higher ramp rate then the S1X making 130# springs the ideal spring to avoid valve float with any type of a decent setup. Paul at PRJ performance can give specifics on this and would normally chime in on a topic like this if it was posted on ClubGP. Its even been said that 90# springs could be a better choice because of OEM reliability and the higher seat pressure. I personally know three people that have had 105# springs break - I would never put CompCam 105s on any car after all the bad things Ive seen and heard.

I have never installed a machined oil pump cover or machined gear on any double roller install Ive ever done. One jank ass JP double roller that was super super stretched on my own car back in the day rubbed but that was a crap chain to begin with. Regardless, you can get the oil pump cover machined for... what, $15 bucks at a local machine shop? There are also people on the forums that will machine the crank gear for $10-15 bucks if you are seriously that worried about it.

without any issues so far

You are also running a big ass pulley and are no where near having a setup pushing the "limits" of that cam.

Last time i spoke with paul he said 105's and a stock chain was fine for an XP.

I find this hard to believe when you can call Paul right now and he will tell you he has never installed an XP cam with anything less then 130# springs.