Putting 87 iroc back togeather 5.7 carb...what is a good 1.5 roller rocker to buy ...not a race car just a mild build with sum 8802 cam and ls6 springs.

Cheers.

 

I have the Gm performance parts ones in 1.6. They make 1.5s also. Gm rebrands them from crane I think. I've had them in for 5 yrs and I've been happy w them. I've had them up to 6500 a couple of times on the dyno and they've been good. They do have a slight sewing machine sound. I couldn't tell you about any power/drivability feel because I did them w a full top end and efi system.

 

Comp Cams makes these in a lot of ratios both self aligning and non-self aligning. They also make then for both 3/8" and my preference 7/16" studs. These are 1.52 non-self aligning and for 7/16" studs. Not cheap but a lot quieter than the Scorpion rockers I had on it before. The Scorpions had a lot of slop side to side creating noise from the trunions.

 

Comp pro magnum are awesome, I put a set of their 1.52 on my 400 sbc build.

 

I found a set on summit made is in usa whic i prefer..there stamped rollers self alignment i think the price is right.

 

Not to hijack the thread, but do roller rockers fit under stock valve covers?...

 

When Engine Masters did their rocker test, the gained essentially zero, going from stamped rockers to rollers.






I have ran aluminum body roller rockers under stock 'Vette valve covers, with the "oil tabs" broken off for clearance.

 

My RRs just barely fit under my aluminum proform valve covers. I had to do a little clearancing. My proforms are larger than stock covers.

I wonder if there is any measurable difference w RRs. Oil temps/measurable friction? I doubt it. Obviously ratio changes aside. Between my blue beehive springs and machined RRs my valvetrain looks very fancy. So at least I have that going for me!

 

not needed.

 

It's hard to believe that RR's don't help...I mean...just LOOK at 'em, compared to stamped! The "fancy looking" valvetrain certainly does "stoke the psychology"...at least it does, mine.

 

Less wear on valve stem tips. They probably last longer too. Probably don't increase power any...

 

Those were not stock stamped rockers they tested either. They were thicker stamped 7/16" stud aftermarket units. Nowhere near how cheesy a stock 3/8" stud GM stamped steel SBC rocker is strength and deflection wise. Increasing the ratio however added a considerable amount of power when combined with the beefier 7/16" stud. At that lift, spring pressure and RPM a 3/8" stud was also out of its element.

 

I know they weren't stock. But the comparison was stamped ball/pivot vs. Full Roller. Obviously, the roller would be better due to less friction. But....it wasn't.

Take-away? Stamped crapity-crap rockers on a 3/8 stud are probably fine for stock and stockish cams and rev ranges.

 

Comparing the same ratio sure. On stock/mild cams though the added lift of more ratio can add a good bit of power. A 1.6 roller even a stock TBI 350 long block gained about 12 whp years when I added them. Engine was noticeably smoother throughout the powerband as well. Also tested 1.7s in place of 1.5s on a LT1 I owned with some better springs. The LT1 gained nearly 20 whp. I also had a mexican Goodwrench crate Vortec engine with the stamped rockers fail in ~25,000 miles as well. The rockers were all worn and the pivot ball pulled through one. Personally I will not run a stamped rocker myself as the supply chain is pretty much garbage now. Pay a little more now or pay a lot more later.

 

Yeah. But THAT was the comparison! Roller bearings vs. a toilet bowl sliding on the bottom of a bowling ball!
And, AND....get this: Psssst! It was the point of, and the original question of this thread -1.5 rockers. OP asked about $pending his $crill on 1.5 roller rockers for a "mild build". If he's looking for $/hp....I don't think 1.5 roller rockers are going to get him much compared the the stockers.

No kidding. Are you saying that if you add more lift....you get a little extra power? Get outta here!

Fear mongering. That works both ways. With trunnion/needle issues, aluminum bodies fatiguing and cracking, push rod pockets getting punched in to the bodies...you could pay more now....and pay more later.

Now before you start in with a pointless rebuttal to ^those issues^, (some of which I've experienced)....let me say that I think the actual occurrences of those problems are somewhere between minuscule and zero....they aren't real "problems" that people need to be afraid of....just like failing stock rockers aren't either. There are plenty of stock stamped rocker'd engines that cruise right on by 200k...300k and plenty of cammed motors, high revver's with stockity stock, sh!tbox stamped rockers....zero rocker issues.

BOTH can and do, occasionally fail, both mostly work just FINE.

 

I doubt his stock rocker arms have a long enough slot to handle that 8802 cams lift. Generally over ~0.470" lift a long slot rocker is needed.

If he wants the cheap stamped garbage, a set of long slot stamped steel run about $100-120. Can get some cyrogenically treated as well that should hold up better for a little more.

The 8802 with a 1.5 rocker is still 0.525/0.520" lift and even with a basic LS6 spring is going to have more open spring pressure than I would want to attempt to run on crappy stamped steel rockers.

 

I agree it's a lot of cam and lift for stock studs and rockers. Which kind of makes the whole point about 1.6 rockers...moot.

I might even say that it's too much cam for the rest of the combo as he described it, but personal preference, I guess.

 

This guy tested a 1.5 Roller vs. an actual STOCK stamped rocker.

Same result; nothing.

 

All I know is they they look cool!

and they were spec'ed w my lt4 hot cam!

 

I mean has anyone ever ran stock syamped rockers on aftermarket aluminum heads?

 

I'm sure someone has. Although, IDK what the head has to do with the rocker.



!! I'd have 'em just for that....and to make my own psychology "feel good" about my rockage.

 

Since it's been brought up more than once that roller rockers provided no power difference. Yet in every aftermarket head build I've seen, they all have full rollers. If not for a performance benefit, why have they been used? Because 'they're pretty' is the only reason we've been given so far. I'm asking in an earnest way, but slightly devil's advocate.

 

I doubt my 383 would run for 10 minutes with a stock stamped rocker. It would easily pull the pivot ***** through the bottom of the rockers with its dual valve springs and lift I am running and that would be if the slots in the rocker cleared and it did not instantly bend the pushrods.

He also tested 1.6 rollers vs stock stamped steel rocker with a mild factory like camshaft. Cam used was very similar to a GM 300 HP Marine aka Ramjet/HT383 grind. HT383 that has basically that same cam profile picks up ~20 hp with a 1.6 rocker.


He also actually cost himself power in that test with 1/2 turn preload. GM specifies 1 full turn on the factory roller lifters. Here is a test of what affect preload has.

https://youtu.be/h4FFtBPbGIE?si=P9BNZnNPIQfYYEzN

 

Freiburger ran a test on them too. Stamped 1.5, roller tip 1.5, full roller 1.5, and full roller 1.6. 7,000 RPM engine.
Also talked about 3/8" stud versus 7/16" stud...

 

A good roller rocker is a durability upgrade. GM upgraded some of their older engine designs like the 2.2L S10 and later Vortec 4.3L to factory LS style roller trunion rockers. Mercury marine uses roller trunion LS style rockers on their 4.5L V6 and 6.2L V8s as well. PSI uses them on their 8.1L derived 8.8L engines. It reduces valvetrain wear especially since newer hydraulic roller lifters limit oil flow to the upper end. Reducing oil flow to the upper end reduces power loss from windage and keeps more oil in the oil pan at higher rpm for the oil pump to actually pump. Limiting windage also reduced oil aeration which can cause power loss when lifters get supplied aerated oil. Bearing life also improves when the oil film is adequately maintained. Newer small block engines were factory built with front lifter oil gallery plugs that were drilled with like 0.025" holes to allow air to escape from them. The added holes also give the timing chain more lubrication for longer life.

 

Good question...
Weellllllll....Let's see an actual, controlled test on that one. You say, I say. I've ran stockity stock rockers past 300k. You pull the bottoms out of them when they're still in the box. OEM's moved to roller trunnions in '97...Aftermarket moved toward bushed trunnions and eliminated needle bearings for reliability reasons. Stamped ball/socket rockers worked great for 40+ years for OEM's, race engines, 7000 RPM LT-1's and DZ302's......So who TF knows. Not you. Not me. Most of the time, either/both are better than good enough. Let's see a test. In the meantime, I'll drop this right here, for the second time....

I've ran both, I'm against neither. I've never had an issue w/a stock stamped rocker in 100's off thousands of miles. I've had problems with aftermarket rollers...but I'd probably run them again anyway simply b/c, yeah, I think they look better and they're cool. They look "race". As Ghey as that sounds and feels to type out. Like I said above; they treat a psychological issue of mine....not an actual one, and I am secure enough to admit that.



There you go again, with the 1.6 rockers. Irrelevant to this thread, and the rocker shoot out that I posted...ya keep crowing about 1.6's. I'll say it again:

I don't think that anyone in this thread has debated the merits of a 1.6 rocker vs. a 1.5. I know that I didn't.