Rollor rocker issue

[JuStBlAzIN]

Ok so i bought a set of comp cams pro magnum rollor rockers (cca-1302-12) with a 1.6 ratio. it turns out they are not self aligning. I will be running mike lee vortec heads with the comp 412 cam, with comp 875 lifter, 987 comp springs. my question is which push rod do i use and how do i align the rockers? or should i even bother and go with the (cca-1317-12) with a 1.5 ratio that are self aligning?

thanks
fred

 

[sy#2716]

Re: Rollor rocker issue

if they are not self aligning rocker you have to use guide plates. Mike sells them on his site. and a 1 peice push rod stock length should work fine call mike he will know.

 

[0260IN3]

Re: Rollor rocker issue

you will need the isky adjustable guide plates for the vortec heads to properly alighn the rockers.

Mike will have those.

 

[JuStBlAzIN]

Re: Rollor rocker issue

whats the main difference with the 1.6-vs-1.5?

 

[0260IN3]

Re: Rollor rocker issue

the amount of overall lift achieved

example: a 4.3 std rocker ratio is 1.5 so on a .500 lift cam, if you went to a 1.6 rocker you would have .533 lift

formula:

valve lift (.500) / std rocker ratio (1.50) x new rocker ratio (1.60) = new lift (.533)

it simple. most guys will put a 1.6 rocker on to achieve more lift and a little more power.

we offer it on all our engines

 

[jwaller]

Re: Rollor rocker issue

it will also affect your duration(albiet not as much as it does lift). it opens the valve quicker so that you can get more air into the cyl quicker.

 

[JuStBlAzIN]

Re: Rollor rocker issue

what push rod do you guyz recomend? part number?

 

[93ty475]

Re: Rollor rocker issue

what push rod do you guyz recomend? part number?

get and adjustable pushrod length checker from summit or jegs to establish the correct length pushrods for your engine...especially if running roller rockers...

 

[tytom]

Re: Rollor rocker issue

get and adjustable pushrod length checker from summit or jegs to establish the correct length pushrods for your engine...especially if running roller rockers...

What he said. Then You will see if stock length is ok, or You need to get some other length...pretty much any decent quality hardened pushrod will do...(usually, most of them are
hardened these days)

 

[ranger]

Re: Rollor rocker issue

Hi Folks,
well, I have the stock heads/cam and would like the extra lift of the 1.6 rockers. Do I need to get self-aligning rockers? Are the Comp.Cams roller-tipped 1.6 rockers self-aligning? In any case, which 1.6 rockers do I need to get to go w/ the stock heads.

Any help is appreciated. Thanks in advance.

Regards,

Craig Stangohr
Aiken, SC

 

[jwaller]

Re: Rollor rocker issue

you dont "need self aligning, but it makes things 100times easier and cheaper in the long run.

 

[HotRodV6]

Re: Rollor rocker issue

yeah i woud get the 1317-12 if you want 1.5 ratio or 1318-12 of you want the 1.6 ratio and the right pushrods are 7940-12. That swhat number i bought for my vortec conversion along with the 1318-12 rockers and 987 springs but im going to use the 422 cam instead of he 412.

Good luck with your build.

 

[HotRudyRod]

Re: Rollor rocker issue

Would using 1.6 ratio on the exhaust or intake side only with a stock cam give you quicker spool ups? If yes, it would make sense to order a double ratio kit. Thanks.

 

[SeattleSy#1255]

Re: Rollor rocker issue

the amount of overall lift achieved

example: a 4.3 std rocker ratio is 1.5 so on a .500 lift cam, if you went to a 1.6 rocker you would have .533 lift

formula:

valve lift (.500) / std rocker ratio (1.50) x new rocker ratio (1.60) = new lift (.533)

it simple. most guys will put a 1.6 rocker on to achieve more lift and a little more power.

we offer it on all our engines

why do people try to achieve more lift through rockers rather than achieving it through the cam?

I don't know, thus I am asking.

TIA

 

[HotRudyRod]

Re: Rollor rocker issue

why do people try to achieve more lift through rockers rather than achieving it through the cam?

I don't know, thus I am asking.

TIA

IMO its a lot easier to install a set of rockers than changing the cam and lifters. It means opening the engine, spending a whole lot more money and time.

 

[SeattleSy#1255]

Re: Rollor rocker issue

IMO its a lot easier to install a set of rockers than changing the cam and lifters. It means opening the engine, spending a whole lot more money and time.

well that makes sense, but i was thinking more along the lines if an engine was out and one was in the middle of building it and deciding on cam specs and rocher choices. It would seem to me it would be better to achieve lift from the cam rather than the rockers, but once again, I barly know what i'm talking about.

 

[HotRudyRod]

Re: Rollor rocker issue

Oh yeah if the engine is out of the truck or the cam needs to be replaced it always makes more sense to go with a performance cam, i just havent seen many cam choices for turbo 4.3s.
And now im wondering if using double ratios would give the engine the extra kick as on NA engines, any one has an idea or tried this yet?

 

[ranger]

Re: Rollor rocker issue

Hi folks,

In response to JWaller's answer to my question whether I need self-aligning rockers w/ the stock heads, his response was that I don't "need" them, but it makes things 100 times easier/cheaper in the long run. Could someone please clarify this a bit?

Thanks in advance.

Cheers,

Craig Stangohr
Aiken, SC

 

[HotRudyRod]

Re: Rollor rocker issue

He probably meant that they are not a must but it would be wise because they're more reliable and carefree, I'd say you listen to him.

 

[0260IN3]

Re: Rollor rocker issue

Hi folks,

In response to JWaller's answer to my question whether I need self-aligning rockers w/ the stock heads, his response was that I don't "need" them, but it makes things 100 times easier/cheaper in the long run. Could someone please clarify this a bit?

Thanks in advance.

Cheers,

Craig Stangohr
Aiken, SC

If you use self aligning rockers you dont need guide plates and any head mods to put them on. The guide plate does the same thing as the self aligning tip on the rocker, it keeps the rocker centered on the valve.

The self aligning rockers are much easier and cheaper.