Roller tip rocker arms and ratio.

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Senior Moment
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Location: Hertfordshire

Roller tip rocker arms and ratio.

Post by Senior Moment »

Hi all.
I am rebuilding my 383 engine. I have a pair of Edlebrock aluminium cylinder heads and am considering replacing the standard rocker arms with roller tip items. (The originals have some wear in the arms and shafts so need replacing anyhow) The camshaft has a standard profile. So I have two questions.
1) Which ratio should I choose. 1.5 (Standard) or 1.6 (which provides a slightly increased lift and duration & potential performance boost)
2) Does anyone have any experience of using (A) using roller tip rockers. (B) Using 1.5 or 1.6 ratio arms?
OK. that's three questions.
Look forward to your knowledge and experience responses.
Martin
1964 CV8 Early Mk 2
VIN 104/2107
PeterHume
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Joined: Fri Sep 14, 2018 12:21 pm

Re: Roller tip rocker arms and ratio.

Post by PeterHume »

Hi Martin
I have comp cams pro magnum 1.5 rockers in my 440.
They appear to be high quality and fitted well.
One thing to be aware of with replacement rockers is they may need more room under the rocker covers.
On the jensen alloy covers it was necessary to relocate the oil baffle on the inside of the cover, I'm not sure if steel rocker covers would have a similar issue.
Regards
Peter
Peterh
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Steve Payne
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Re: Roller tip rocker arms and ratio.

Post by Steve Payne »

I have been using them for years but I went for 1.6 to give the cam a boost, I would also only use Steel or stainless steel and not aluminium as they can wear quicker.
The other benefit is less friction in the engine so its a good idea.

Steve
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Senior Moment
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Re: Roller tip rocker arms and ratio.

Post by Senior Moment »

Thanks for the really helpful feedback
Potential clearance issues with the stock Jensen alloy valve cover is a good watch point. Thanks Peter.
I did think about changing the camshaft as mine needed replacing (see a previous post on this) but stuck with the standard profile for drivability. So the idea of gaining a bit more oomph by increasing the rocker ratio has it's appeals, not least the simplicity of reversability. Interesting to see how this will work with the free-er flowing Edelbrock heads. Thanks Steve.
Here we go then.
Martin
1964 CV8 Early Mk 2
VIN 104/2107
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Steve Payne
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Re: Roller tip rocker arms and ratio.

Post by Steve Payne »

The rocker covers will be fine it is the splash guards inside that are the problem, two options. Remove them completely or drill a hole immediately above each adjuster screw so they don't hit.

Steve
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Hangtowner
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Re: Roller tip rocker arms and ratio.

Post by Hangtowner »

I have Mopar factory iron adjustable rockers on my car and a few of the rockers just kissed the baffles inside the valve covers. I raised the baffles about 1/4 inch by removing aluminum from the mounting posts.
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Grant
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Re: Roller tip rocker arms and ratio.

Post by Grant »

If your rockers are fouling the rocker covers just fit thicker Cork Rocker Cover gasketsImage
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