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VS cam pulley size?

I am swapping from 1.9 rockers to an S1X in a couple weeks along with a gen v. Think I will notice a big increase in power?
 


Yes you will feel a big difference from the 1.9s, that was what I did before. It was awesome I loved that build too.

Didn't get the cam for free just a good price. I'm not going back to that setup sp everyone STOP TELLING ME TO GO XP/S1X!!! Been there done that!
 


like, 4200 is where it starts with a float happy setup... Boost is going to float you before RPM does.. and RPM related floating is usually found in places other than the valvespring pressure to rocker design "ratio" (valvespring harmonics, lifter harmonics, valve spin).

The lift is really the killer part... the 1.8 even struggle to keep up with stock rockers power wise (at least on my crude "tuner dyno" that looks at boost pressure/maf flow)... and the camshafts out there have been mainly designed to produce their gains around the variable ratio stock rockers, so its likely you go backwards a bit with the extremely square looking lobes found on our performance camshafts.

I would like to have some dyno testing of this... but i really doubt its worth the effort as nobody with normal heads / normal boost levels needs to ever worry about NEEDING a big dog rocker to make power.... The small handful of us guys with heads and boost pressure that requires these big dog rockers (for reasons of adjust-ability and 150#+ springs) will be concerned about float, but we will then be able to overkill the springs/lifters/pushrods to compensate.

Overall, anyone with a roller rocker that has a nearly stock mounting system (not shaft mounted / stock bolts) has a completely useless and most likely power reducing part on their car.
 
I have stage 3 heads so you posting about all this was pretty pointless here. My float is compensated by my springs, lifters and pushrods. And since you have no dyno or anything to back up your theory I don't understand why you keep telling people no to use rockers.

Personally I'd rather you roller rockers knowing that they are 1.6/1.7/1.8 over stock that range from 1.6 to whatever. That might just be me though.

My question about what pulley size to use was answered on page 1, can we close this thread and start a new one if we all want to argue about valve float since it had absolutely nothing to do with OP.
 


Swiggles said:
I have stage 3 heads so you posting about all this was pretty pointless here. My float is compensated by my springs, lifters and pushrods. And since you have no dyno or anything to back up your theory I don't understand why you keep telling people no to use rockers.
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Uh, no its not... Just because you have PORTED heads means you would make MORE gains from more lift.. so its even MORE relevant in your case. The fact your heads were touched by intense do not mean you have a rhodes lifters, custom pushrods, and adjustable shaft mount 1/2inch stud mounted rockers and 150# springs running 600 lift.... in fact you are running a tiny cam with lift similar to a stock cam/rockers!

The reasons people HAVE to run roller type rockers are completely irrelevant to you, so there is no reason you should have them... but obviously the above reply was just done to troll me, as you obviously didn't even read my post.

Personally I'd rather you roller rockers knowing that they are 1.6/1.7/1.8 over stock that range from 1.6 to whatever. That might just be me though.

My question about what pulley size to use was answered on page 1, can we close this thread and start a new one if we all want to argue about valve float since it had absolutely nothing to do with OP.
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uh, as I said before, pulley size vs peak power is very reliant on what rockers you should run..... as you will make best power not floating over floating a small pulley.
 
I wasn't trying to troll you, I guess I just don't understand what your saying. and you said it yourself that you havent done the testing and that your measurements weren't accurate.

So what would be the case for me to need rollers? More lift means more power unless I'm floating and it's bleeding off, right? So if pulley size X causes more float than pulley size Y, I'd stick with Y.

And others have made alot of power with 1.7s, stg3 heads ( I have zzp ones not that's it really matters) and the vs cam. Why would I be different?
 
No, nobody else makes power going to 1.7s... I can find more than a few that lost 20+whp though.

I said I can not produce some numbers due to the lack of precision in my test rig... It does not mean that the rest of them are incorrect.
 
Can you find them and show me the numbers? I'm not saying its impossible, I'd just like some proof of rockers being the only difference causing that much of a loss.
 


wanting to get to the bottom of this i emailed zzp about loosing 20whp with 1.7 rockers. Here is what tim replied to me

Nah, that isn’t true, in fact we gained like 5whp on a VS cam car with Stage 3 heads going from stock to the 1.7s. But that is on a set of fresh valve springs, I could see issues in the future with the 1.7 rockers.



Thank you for your business,



Turbo Tim
ZZPerformance.com
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i replied asking what issues in the future?

Wears out valve springs quicker, therefore gets valve float sooner than with the stock rockers.



Thank you for your business,



Turbo Tim
ZZPerformance.com
Click to expand...
 
And that makes sense with any change in valve train geometry. Which is why I always preach about changing springs when doing valve train changes.
 
Started with the 3.0 and had zero knock! Dropped to the 2.8, got a little knock up top, just have to tune it out. It feels amazing!!
 
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