Rocker arm questions

[beardeddummy]

I have a stock vortec 5.7 and was wondering if I could get more out of it with 1.6 rocker arms. If so will the stock heads handle it and will I need my tune adjusted. And about how much difference would I see

 

[skylark]

If you are stock you will go from .414/.428 to .442 and .456. Decent gains but nothing that will excite you. Don't go over. 480 on stock valve springs and retainers. Several companies offer spring and retainer kits to go to. 550.

 

[skylark]

I should add that if you want to keep your stock rocker covers then you need to use a narrow body rocker arm. Either way you will need self-aligning or have to use guide plates. Vortec heads use round push rod holes instead of the earlier heads that had slotted push rod holes.

 

[Supercharged111]

I did 1.6s and had to yank the heads to drill the pushrod holes bigger. I then replaced the valve seals and pounded them all the way in to gain more clearance. Offset locks are not really the answer here because you lose rocker arm clearance with the self aligning nubs. That said, I have a marine cam with 1.6s on stock springs. Reason I stayed stock is because GM sells crate engines with these springs with the marine cam and 1.6s.

 

[beardeddummy]

Sounds like a pain in the butt could come from this task

 

[Big D]

I used Scorpion self aligning Roller rockers , I didn't have clearance issues with the push rods, I was able to use my stock valve covers. I also upgraded the Spider fuel Injection and added a Vmax Intake manifold spacer for more plenum volume and I cleaned the **** off of the the lower intake and did light porting so I cant say what the Rockers did on there own, but she ran a hell of alot better afterwards.

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[beardeddummy]

I'm thinking either a vmax spacer or completely different intake. But with my budget it will probably be spacer and spider.

 

[beardeddummy]

Did you have any pushrod clearance issues

 

[skylark]

I did the vmax on our old Denali. Not worth the money and I bought a used one. I did scorpion 1.6's as well. They were worth the money.

 

[beardeddummy]

Skylark I have learned a lot from you do you think the vmax spacer would make more difference with ported heads feels like full throttle starves my engine of either air or fuel at higher rpms. Although i don't think I make enough power to outrun the injectors I do have the original spider at 253k. I am making much more power down low and up high at 3/4 throttle