https://classicmotorsports.com/articles ... ld-big-ga/


From an article on another forum.

Greg

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http://www.youtube.com/hyperpack

Interesting read.
Thanks Greg.

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-MattMan
LEANED & MEAN

I have 1.6 Rollers on 2 of my engines... Hopefully a 3rd coming up.

This was written and tested by British sports car folks... so somewhat applicable to our engine platform.


Notice that they say the biggest bang for your buck in the N/A engine is in the head! Get it to flow!

Greg

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http://www.youtube.com/hyperpack

CHA-CHING$$$

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-MattMan
LEANED & MEAN

I have tested my 1.6 rollers against my stock RAS rebuilt rockers at the track, same day, same weather. 0 difference.

1.6 is a band aid for a too small camshaft.

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Official Cookie and Mater Tormentor.

1.6 rockers (bushing) will give you a smidge less weight "throw" for a given valve lift, all but entirely in the lifter & pushrod travel. And this at the cost of a smidge higher lobe/lifter loading. Strictly a tach thing, and hardly measurable in effect on anything less than a killer build.

Add rollers to the 1.6er, and the smidge less drag might compensate very slightly for the higher lobe/lifter load.

Dumbbell lifters, recessed top keepers (both available stock), and shaving a bit off the top/nose of the stock rockers'll get you 6000 quite nicely for even a reasonably warm built slant. After that it's what it always has been; the cam's ramp profile.

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Sex, drags, and rock & roll.
Dick, 225% crazy.
Hobby (cars, that is) Photos link

You have evidence that your engine did not benefit from more valve lift or the slight increase in seat duration. There is evidence for other engines to support the use of higher ratio rockers instead of a longer duration cam. What the Classic Motorsport test shows is that on an A-series engine with a long duration cam that low and mid-range torque suffers with higher ratio rockers. I'd like to see a test with a milder cam.

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Joshua

You probably wont see a gain of even 12 to 15 HP in a heavy car unless it's a state of the art Super Stocker or Comp Eliminator car. So trying to judge the merit of a product that has such a small gain is difficult. Just know that the payoff for roller rockers is in the fact that all 12 valves now have the exact same ratio instead of a stamped rocker that you'd be lucky if 2 of them had the same ratio. Can you warrant the cost, probably not. But other benefits are there whether you recognize them or not.

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There's no such thing as too much cam....only not enough engine!

Like, they look really cool! But who can see them??? Now where did I put my Lexan valve cover

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

The reason for us to make our own roller tip rockers was to get all rockers the same ratio and have adjusters that don't back off. It sure is nice not having to check the rocker arms after every run.

Mark

Most of us don't run a .900" lift roller like you rich guys.

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Official Cookie and Mater Tormentor.

I bought longer adjusters and half nuts from Smith brothers for that reason.

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2 Mopars come with Spark plug tubes. One is a world class, racing machine. The other is a 426 CI. boat anchor!

12.70 @ 104.6

I don't even have any of that fancy schmancy stuff. I did check the rockers on my junk before the season. I had to tighten a couple exhausts up .002".

I think I only made about 60 passes last year though.

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Official Cookie and Mater Tormentor.

My longer Rocker Arm Screws / Adjusters Poke throught the valve cover sometimes.




Greg

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http://www.youtube.com/hyperpack

Whoa, Shots Fired!
Dang.

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Hyper_pak