Getting a custom grind for stock heads. My research tells me the added lift of 1.6's on stock heads doesn't do much for the cost so I would like to avoid buying them. I will be upgrading springs/retainers. In all reality the added gain comes from the roller and not the lift on stock heads. I was thinking around .500/.500 lift with the 1.5 stock should be fine? If I can do a little more than that I would but not sure and would like opinions! I won't be reving my motor past 6k and not very often since it is an auto.

Anyone using stock rockers with aftermarket cam? If so what is the lift and what do you rev to?

 

1.6's do give decent power increases. But we upgrade for peace of mind just as much as power increases. Gains come from both the roller and the extra lift. Most cams are rated at 1.6 RRs anyways. My cam the difference is almost .050 lift. Tell me thats not very important lol.

There is no set limit, but I can tell you that with a cc306 I destroyed 1 stock rocker and the rest were pretty nasty looking after only a few days of driving. By some unseen force it managed to breack just enough of the tip off that it wasn't pushing on the valve tip, but was hitting the retainer. Some how the locks held it in place. I wouldn't risk it. Crane's are $150 used. Comps with guide plates are oonly a few dollars more.

 

Look at flow sheets for stock heads an explain to me how that extra .50 lift is helping sooo much. Ever hear of flow reversion?? Too much lift on a head that does not flow that well is actually detrimental to hp/tq. And our heads do not flow well unported. From the charts I have seen past .500 lift is a waste/excessive on the intake. More lift on the exhaust does seem to be where any gain is coming from as the exhaust port is very restrictive on our heads and does flow better as lift increases (to a point).

Well the cc306 has .540 lift on the exhaust side with 1.5 so I can see why you broke your rockers. How high were you spinning the motor? What kind of springs were you using and what was max lift? FYI most cams are rated using 1.5 rr. I agree on the peace of mind but in my book the added cost does not justify the meager gain. And if I can avoid the risk by using lower lift on my custom grind that is 150-250 less that I can spend on something more beneficial.

 

You seem to already have a firm opinion about 1.6 rockers. If you don't want them then don't get them. Have your cam ground with the lift you want to use with the 1.5s.

 

Agreed.

-Dustin-

 

I was spinning it to @ 6500. Yes I was at fault for them breaking.

You have seen/held a stock rocker and an aftermarket? If you value your investments then a few hundred more is not a big deal. I have tried to do the budget way of things before. The stockers are flimsy.

On a .500 lift cam, whose to say? Yes it can and has been done.

Cam choice is an age old argument that will never end, so I won't bother.

If your mind is already made up then I don't know what to tell you.

 

thanks for all the opinions. I was really just looking for somone that was doing alright using the stock rockers with an aftermarket cam and what lift the cam was.

 

I would not bother to install a custom ground cam and then leave the stock rockers on there. At least upgrade to full roller rockers, but just get the 1.5 ratio (if that is what you want to stay with).

 

I'm running the LT4 hotcam with the associated springs and hardware, with stock stamped 1.5s. The car just turned 107 MPH in the 1/4, with a mail order tune and some bolt ons. I have not had any problems, but 1.6 rollers are on my to-do list.(or 1.5 rollers if I find a smokin deal )

 

Guess we better tell all the people who make 350+ rwhp with high lift (.55-.6) on unported stock heads that they need to go back to <0.5 lift so they don't have flow revesion.

You need to do some research before you throw away money getting a cam/rocker combo with such ridiculously low lift.

Again, you don't know what you're talking about. Do some research on LT1 heads and how they compare to all the SBC heads that came before them.

Your research is crap.


For the answer to your question in the OP, feel free to refer to your other thread with the same question:
http://web.camaross.com/forums/showthread.php?t=446598


For more info on max lift, cam choice, etc., feel free to refer to your 20 other lift/cam threads...

 

I've seen pictures of stock rockers on here destroyed from using mild cams with them. At the very least upgrade to a full roller of some type.

And you're research about losing power on stock heads with over .500 lift is horse****. My old XE503 with 536/544 lift did 112.81 MPH in the 1/4 on bone stock heads with 1.6 RR's.

 

Thanks Javier and Steve. I know 380 is sad in comparison to many motors on here, but then again it is with stock heads.....