305 rockers

[LukeZ]

I found a thread on this from 2011 pretty much asking the same thing but I just want to make sure.
https://gbodyforum.com/threads/can-you-bolt-on-1-6-rockers-on-a-stock-305.32736/

Looking for something fun to do after finals in a few weeks. So if I just did plain old 1.6 stamped steel Summit rockers, do I have to change pushrods and lifters too? Or can I just do the rockers and be fine?
https://www.summitracing.com/parts/...ikNv8H4J81VrcCqYXwmR6OZat6tR5QgoaArLREALw_wcB

Do I need new valve springs? Is it as simple as taking the old ones off and putting the new ones on?

 

[pagrunt]

Summit said you'll need guide plates in the Q&A section. which means you'll need to change out the press in stock rocker studs for screw in ones. I'd stick to 1.5 rockers.

 

[DRIVEN]

I saw the same note that pagrunt referenced. Since they don't appear to be self aligning, guide plates would make sense in some applications. I suspect (but don't know) that you'd be fine. If the hole in your heads are just wide enough for the pushrod side to side, I'd give them a try. If the pushrod holes allow any lateral movement, you would need guide plates or self aligning rockers. Your lifters and pushrods should be fine.
Also read the last post in the thread you linked. He's talking about coil bind and retainer interference. Neither of which you should be too concerned with if you have a stock or mild cam. SBCs are pretty forgiving.

 

[LukeZ]

Does anyone have a good video to share on how to swap rockers? Pagrunt what do you mean I'll need screw in studs? Are the stock studs just pressed in? So if I went with guide plates, would I need to tap the old holes to get new screw in studs to hold the rockers?

And DRIVEN, I saw a response on Summit from one guy who said the same thing as you - that if the cam is small then it would be fine without guide plates on the street.

 

[pagrunt]

The studs in your heads are pressed in & can not use the guildes. If the guildes are needed, the studs will have to be pulled, the holes tapped for the screw in studs which will hold the guides in place. With the exception of a few factory high performance heads, all SBC's have pressed studs.

 

[LukeZ]

The studs in your heads are pressed in & can not use the guildes. If the guildes are needed, the studs will have to be pulled, the holes tapped for the screw in studs which will hold the guides in place. With the exception of a few factory high performance heads, all SBC's have pressed studs.

If I tapped the heads, where would the metal shavings go? Are there any cavities below where I would be tapping? Would I have to worry about going too deep and ruining the heads?

 

[DRIVEN]

Installing screw-in studs just to run guide plates just to run 1.6 rockers on a 305 is waaay more trouble than it's worth.
A simple rocker swap isn't even going to give you any real noticeable gain. It's a relatively cheap and easy endeavor and it's good experience, just don't expect to notice any difference. But please don't go as far as screw-in studs. Absolutley no return on your investment.

 

[pagrunt]

I have never done/tried to tap the stud holes. It would be best to send them out foa good machine shop to do the work. Don't over read this that you have to do it. Check out other rocker options, don't use the self aligning type or ones thar need poly locks. This way you won't have to replace the studs & keep your budget in check.

 

[LukeZ]

I can just swap the rockers and be fine, reusing the stock studs? Sorry haha, I just don’t know too much about it and I don’t want to mess it up

 

[DRIVEN]

Probably. Just remember, free advice is worth exactly what you paid for it.