Jesel Sportsman Rocker Setup

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Jbirken
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Jesel Sportsman Rocker Setup

Post by Jbirken »

Looking for some feedback on Jesel Rocker arm setup. This is going on a 8.2 SBF with Mike Jones solid roller. It's a "baby" lift at .570" as intended to be an "endurance" valvetrain.

I've read most of the "Mid Lift" vs "Low Pivot" discussion, and without opening that can of worms, I wanted some feedback specifically on the pushrod side.

The below shows the comparison between "Mid Lift" and "Low Pivot" on this setup. The "Low Pivot" setup trades 3* pushrod angle between closed and full lift, but there is still 2X difference between the two states. Is 7* and 14* Pushrod skew at close and full lift respective reasonable for a low lift cam like this?

Top row is "Mid Lift", bottom row is "Low Pivot". Left to right closed to full lift.

Thanks for the thoughts.

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Charliesauto
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Re: Jesel Sportsman Rocker Setup

Post by Charliesauto »

Bottom row is closer to Jesel's recommendation.
stealth
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Re: Jesel Sportsman Rocker Setup

Post by stealth »

None of those pics looks right to me...

Per Jesel:
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Jbirken
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Re: Jesel Sportsman Rocker Setup

Post by Jbirken »

Thanks for that schematic. I was a bit disappointed with the setup literature that came with these rockers. It seems they want you to pay for the setup tool to get the goods.

Can you be a bit more specific in what doesn't look right? I realize the valve tip contact is biased towards the exhaust, but I believe that to be because I am using lash caps + shims to set the height. Raising the valve tip brings the tip closer to the rocker and biases contact towards exhaust. However, once I settle on the right relationship, I plan to machine the rocker base to get the right height. If I machine the base .150", it should pull the tip contact back ~0.050" and better center the tip contact (20* valve angle).

If I take Jesel's recommendation and adjust for .570" lift in lieu of .850" lift, it looks like I am actually a bit low compared to their recommendation at my "Low Pivot = normal to valve at 66% lift" (valve closed) configuration; below.

If I raise it up to match Jesel's recommendation, pushrod skew at full open will get worse (see "Mid Lift" setup from first post).

Edit: I suppose I could try their pivot .225" below valve tip as that should help the pushrod skew situation, but that means the rocker wont go normal to the valve until much later than 66% max lift.

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Jbirken
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Re: Jesel Sportsman Rocker Setup

Post by Jbirken »

Actually, it looks like my "Low Pivot" height is bang on the Jesel recommendation.

The schematic is pivot .225" below tip for .850" lift. The instructions attached say +0.050" for lift above .800", and -0.050 for lift below .600". So .225" -.050 - .050 = .125" below tip. Right where I'm at with "low pivot".

The question about the pushrod skew still stands.
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Re: Jesel Sportsman Rocker Setup

Post by stealth »

You have a very nice set of rockers....buy the set-up tool...looks like its around $10. Chump change for piece of mind and assure the success of very expensive parts...
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Re: Jesel Sportsman Rocker Setup

Post by stealth »

Tool part numbers
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Re: Jesel Sportsman Rocker Setup

Post by stealth »

Price
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