Roller Rockers

[wb292]

I’m starting my 350 build to replace my tired 350. Im gathering parts at this stage. Do I need self aligning roller rockers for use on TBI heads?
Thanks

 

[PlayingWithTBI]

Yes, unless you go with guide plates and hardened push rods. These are TBI heads and they come with guide plates.

https://www.summitracing.com/parts/sum-162108/make/chevrolet

 

[Erik the Awful]

If you run guideplates, use regular rockers. If you don't use guideplates, use self-aligning rockers. Are you building a high-rpm motor with good heads? If not, don't spend extra money on roller rockers.

If you have access, Engine Masters episode 29 has dyno testing of different rockers to see if there are any horsepower gains. My takeaway is to spend the money on 7/16 studs. Also, I looked for 1.6:1 stamped steel self-aligning rockers, but nobody seems to be making them for a decent price.

 

[wb292]

Thanks for the replies. it's been quite a few years since I tore down a TBI 350 and I couldn't remember if they used guide plates in these engines. I am going back with close to a stock engine. I am going to use a rebuilt ATK long block with a stock roller cam. Although I don't know the specs on the cam would be. I assume it would be a stock cam for a caprice or something close. Since this truck will be my daily driver, my goal is fuel economy. I got 17.9 on the last tank. It's a SC SWB K1500 with a 5speed. So I'm planning on using a set of roller rockers to help with mileage. I rarely make any shifts above 3500 RPM so the low end torque the swirl port heads provide. Although I'm planning on going with a 1.5 ratio, would I see any improvement going to a 1.6 ratio with a stock cam?

 

[PlayingWithTBI]

Although I'm planning on going with a 1.5 ratio, would I see any improvement going to a 1.6 ratio with a stock cam?

If you go to 1.6 rockers, you'll get bigger lift, obviously. Take your advertised lift with 1.5 rockers divide by 1.5 and multiply by 1.6, that'll give you your static lift. I wouldn't buy an engine unless I got all the info about it including the cam card showing your lift, duration, grind timing, LSA, etc.

 

[Erik the Awful]

So I'm planning on using a set of roller rockers to help with mileage. I rarely make any shifts above 3500 RPM so the low end torque the swirl port heads provide.

Roller rockers really only help above 5000 rpm. Your friction losses aren't going to be noticeable in gas mileage.

 

[Awest623]

If you run guideplates, use regular rockers. If you don't use guideplates, use self-aligning rockers. Are you building a high-rpm motor with good heads? If not, don't spend extra money on roller rockers.

If you have access, Engine Masters episode 29 has dyno testing of different rockers to see if there are any horsepower gains. My takeaway is to spend the money on 7/16 studs. Also, I looked for 1.6:1 stamped steel self-aligning rockers, but nobody seems to be making them for a decent price.

https://www.kmjperformance.com/i-24...s-1-6-long-slot-late-model-self-aligning.html

I use these. 1.6 self aligning stamped steel. $8 a pop. Can report not a single issue with my set.

 

[wb292]

Thanks for the help. I just might go with the 1.6 ratio

 

[nobears]

https://www.kmjperformance.com/i-24...s-1-6-long-slot-late-model-self-aligning.html

I use these. 1.6 self aligning stamped steel. $8 a pop. Can report not a single issue with my set.

These should work on my 88 4.3 shouldn’t they?

 

[Erik the Awful]

I've never torn into a 4.3, but yes, they should. Test fit the heads and entire valvetrain before you do your final assembly. You might have to clearance the pushrod holes when running 1.6 rockers.