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Looking for help picking a timing set and a cam for a moderate 489 build

Polymath

Polymath

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Simple question (I hope). I'm a bit of a newb at selecting parts for an upgraded motor. I've only ever really replaced things with OEM parts. So, with all the hulabaloo about double rollers being "better" than a standard timing set and the insane amount of variance in cam and lifter choices, I want some opinions or facts from those that have been around the engine block a bit more than myself.

The build is a BBC 489 on a Gen v block. Not looking for killer high performance. This is going in my k5 as a replacement for the wimpy old 305. Heads will mostly likely be small CC edelbrocks with a performer manifold. Should see 8.5/1 to 9/1 compression with the flat pistons and 110CC heads. Not sure on which cam yet but the goal is easy idle with a lower end power band. Again, daily driver, family friendly, camping/hunting vehicle. Not a hot rod. Maybe some light towing but unlikely to ever see max towing capacity.

As for the timing set, I think I want full roller rockers and all that jazz which would mean higher spring rates which could mean I need something better than an OEM timing set. But I also think that hot rodder marketing teams thoroughly convinced me that roller=better. I really don't know if i'd see any noticeably better performance or perhaps more longevity and reliability over a simple hydraulic lifter set and plain old steel rockers.

Money is of course a factor but i'm not against being patient and saving up to buy the right parts the first time. Buy once, cry once.

TL/DR: full roller rocker/lifter setup with double roller timing set or just use a standard hydraulic cam/lifters/rockers and a standard timing set? I want 100,000 miles without things wearing out. Breaking can't always be controlled but I don't want race parts that are only really designed to last 25k.
 
A roller lifter is nearly always better if it fits the budget. You can open the valves faster and further in the same duration and get more power and torque in the same RPM range. This is even more helpful with aftermarket heads that flow more and take more lift.

I can help you plan the whole engine build to work together with your vehicle combination if you want. I would be glad to get you the parts as well. I use my app I created to calculate static and dynamic compression and help you select the best parts to meet your goals.

I like your plan, buy it once and be done.
 
I did not know about this app previously.... I need to play with it tonight.

The roller lifters always sounded great for performance, but what about longevity? Do they last like a modern engine should? I was thinking that using steel roller rockers would alleviate some of the worry with aluminum cracking under the heavy spring rates. But even so, more parts in the system can sometimes equal more wear points and less durability.
 
Polymath said:
I did not know about this app previously.... I need to play with it tonight.

The roller lifters always sounded great for performance, but what about longevity? Do they last like a modern engine should? I was thinking that using steel roller rockers would alleviate some of the worry with aluminum cracking under the heavy spring rates. But even so, more parts in the system can sometimes equal more wear points and less durability.
Click to expand...

The factory uses roller lifters in GM V8s since the late 80s, they are the new standard for performance and longevity. I don't recommend a solid roller for longevity, but a hydraulic roller of a reputable brand is very good. On the roller rockers, I typically recommend steel for street driven vehicles just because of the fatigue life curve of aluminum vs steel. However, with a hydraulic roller cam the spring pressures are low enough an aluminum roller rocker can last for decades. Wheras with 800 - 1000 lb open spring pressures aluminum rockers have a pretty limited life, especially with boost on the exhaust side.

Bent77 said:
@folkenheath are there certain brands of roller lifters that have service life issues?
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I try to stick with the reputable brands, I sell more Howards Cams setups than any other, they are a WI company and they only use USA made lifters. I also sell Comp Cams among others depending on the application. I do not recommend any knock-offs or generally cheap options when it comes to engine parts, especially lifters, you know what I mean.
 
Cloyes is OK quality but they stretch pretty easy. My favorite brand is Avon ProGear 4000 series but they are often hard to find. I used to get them from my engine machinist but he retired.

Chevrolet 4000-Series – Progear

www.progearweb.com

I sell the most of the Howards billet timing sets. They are a true double roller chain (some are not actual roller links), and they have 9 keyways for 2 degree increments when I degree the cam in. Yet they can't move. I don't like the adjustable sets that have slots because I don't trust they won't move over time.
 
Don’t give up a greater and more useable power curve that a proper hydraulic roller set up will provide - does not have to be “all-out” performance kind of deal; a roller lobe profile will give a fantastic valve opening and closing events for superior results.

It’s definitely worth the extra money !!
 
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