XPZ or SIX w/1.8YT Rockers?!?!?

[GMR Badass]

Need some input on which route to take on my build that is currently in progress. Do I go with SIX (which is in the car) and add 1.8YT Rockers that I have or ditch the cam/rocker combo and go with the XPZ cam. I don't take the car to the track often and it's more of my weekend car to have some fun with. It will see a few track passes this year with the addition of the built trans that I just put in. Long term goal is to have this motor in a Brunton Auto Kit car (Stalker 7) in the future. Any thought on advantages/disadvantages of going either route? Need come guru's input here!!

Build will be:
L36 Bottom End
IS3 Heads (130# springs)
GenV
Full IC
N* LQ4
Headers,
Double Roller
80# injectors
E85

I have been reading a ton of posts from back in the day about several different cam/rocker/cam&rocker combos and I'm torn on which direction to go. Shooting for that ultimate goal of 400whp on a supercharged setup. I don't want to go turbo because future plan are to put in the kit car which is setup for being supercharged.

Here is what I was able to put down with my current setup which is in my sig.
Run 1(red): 2nd gear pull
Run 3(blue): 3rd gear pull

 

[Swiggles]

thanks for destroying my financial future, now i have to save up for that kit car :th_tongue2:

if your looking for 400ish id go with the xpz.

 

[BillBoost37]

Look up Todd Allen's 8-ball build on Intense's website. That was a S1X with 1.8 car with all the dyno runs and specs etc. I followed that setup and it fetched what felt very healthy. I think his best dyno was 373whp. Never dyno'd mine or made it back to the track.

Not sure what the numbers on the XPZ are. Might be a better route.

 

[Swiggles]

bills s1x 1.8 was fun to ride in. could hear the SC wine from 3 cars behind him with the windows closed

 

[GMR Badass]

Look up Todd Allen's 8-ball build on Intense's website. That was a S1X with 1.8 car with all the dyno runs and specs etc. I followed that setup and it fetched what felt very healthy. I think his best dyno was 373whp. Never dyno'd mine or made it back to the track.

Not sure what the numbers on the XPZ are. Might be a better route.

Todd's build is originally what I based my build off of. About the only difference is that I will be running an L36 bottom end rather than the L67/L32 bottom end. I have been searching through tons of cam articles to get a better idea of which setup will be ideal for what I plan on doing with the motor in the long run. I know Todd daily drove that car 50 miles round trip every day to work. I just wonder how that setup will do on the track with a kit car. Both setups claim to have very broad power bans.

bills s1x 1.8 was fun to ride in. could hear the SC wine from 3 cars behind him with the windows closed

I actually got to drive Todd's car before he ended up buying his G8. Very fun ride and had tons of power. I've never been in an XPZ cammed car and I'm hoping a few people that run the cam chime in about it.
P.S. Sorry about ruining your financial future!

 

[BillBoost37]

The best was when buddies said they heard me, they were close to a mile off. I also drove Todd's car. That was what killed my finances at the time.

Read up on the XPZ. I like what they say about it. Might be fun to toss 1.7's on it.

 

[GMR Badass]

The best was when buddies said they heard me, they were close to a mile off. I also drove Todd's car. That was what killed my finances at the time.

Read up on the XPZ. I like what they say about it. Might be fun to toss 1.7's on it.

Right now the GenV screams with the 2.8 pulley on it!! Should post in the race section but I'm pretty sure I scared 2 guys (around 18 or 19 punk age) driving a WRX STi....don't think they had any idea what the GTP was capeable of.

I would be all for throwing a set of 1.7's on them but I have a feeling that would be requiring custom pushrods to be made and that's when the cost just starts climbing higher and higher. SIX w/1.8 is a unique setup but would be the more expensive route since I can sell the SIX and brand new 1.8's I have and just run the XPZ. Wish there was someone local to me that had the XPZ cam so that I could ride/dive the car.

 

[BillBoost37]

XPZ says it requires two different length rods. One for intake and one for exhaust. and then does say you can toss 1.7's on top ofit.

 

[darkhorizon]

Sigh.. This thread...

Where do I start?

Lets get some myths out of the way...

1.7 rockers on a cam setup will decrease lift and increase floating. That is a fact.

1.8 rockers offer little to no gains over stock rockers... They do open up options for doing crazy stuff with valvesprings heavier than 130# and shift points over 7000 rpms (gotta have the springs to support the crappier rocker setup)

Custom pushrods are not required for any of the rockers out there... YT's come with custom pushrods just because they do... You can run those pushrods on any cam that does not require custom ones.

The XPZ requires custom pushrods because of the weird design of the cam to get that much lift out of it... Its not a "requirement" per say but it does help keep lifter preload in check on paper anyway.

 

[GMR Badass]

It looks like on ZZP's website they make it sound like that can only be done with their Stage 4 heads and the comp cams rockers...I have the Yella Terra rockers wich use the longer pushrods.

Stock pushrods are 7.050
Yealla Terra pushrods are 7.300 IIRC

Not sure why you think that you can just run any rods with any setup. You make it sound like anything but stock rockers will make the valves float instantly which is crazy to me. Why is it that several people have done cam/rocker combos in the past and show no signs of valve float....

 

[darkhorizon]

It looks like on ZZP's website they make it sound like that can only be done with their Stage 4 heads and the comp cams rockers...I have the Yella Terra rockers wich use the longer pushrods.

If you feel like you have to use crappier rockers to decrease power, then just measure out the difference in pushrod length to stock and adjust accordingly. I was able to make a set of custom length pushrods for fairly cheap... ordering a set shouldnt be a big deal.

At the end of the day you are still just adding complication and reducing horsepower though.

 

[Swiggles]

Rockers do not cause float until the valve springs wear out. Fact!

 

[darkhorizon]

heavier rockers float more than lighter ones, fact.

 

[Swiggles]

And heavier springs cause less float because they are tighter. Roller rockers don't instantly cause float like you are trying to tell everyone all of sudden in the year 2012. If this was common knowledge like you say it is then no one would want to do this. I'm not saying it will never happen but it isn't instant. And there are things to combat float.

 

[darkhorizon]

sigh...