Harland Sharp Roller Rockers

So your seat of the pants gains were RRs PLUS tune, right? I mean, there was no tune on it before you swapped on the RRs.
 
So your seat of the pants gains were RRs PLUS tune, right?

Don't forget, the change in ratio changed the effective cam profile. So his seat-of-the-pants feel was from a change in effective cam profile, a change in tune and timing.

Full roller rockers would net no significant power differences in something making the power of a 4.0. IIRC the guys on engine masters showed no power change from a stamp steel rocker vs full roller rocker on a 500 hp engine.
 
Yes, bearing failures at both the fulcrum and roller tip, common in mopar v-8 applications, not so much in Jeeps just based on volume of installation
They have a rather limited lifespan compared to stock rockers correct? Like 20-30k? I almost got some harlans but didn't for that reason
 
Don't forget, the change in ratio changed the effective cam profile. So his seat-of-the-pants feel was from a change in effective cam profile, a change in tune and timing.

Full roller rockers would net no significant power differences in something making the power of a 4.0. IIRC the guys on engine masters showed no power change from a stamp steel rocker vs full roller rocker on a 500 hp engine. Also

I started with the tune but with the rr was better. Still say rr was the best add on. I also have 62mm tb. Stock intake. For 180k motor sure is strong up to 3500.
 
I've had a set of 1.7 Harland RRs for my 96 Ram with the 5.2 (factory ratio is 1.6) on my wish list for a while.
 
Don't forget, the change in ratio changed the effective cam profile. So his seat-of-the-pants feel was from a change in effective cam profile, a change in tune and timing.

Yep, and that's why I asked what cam. I think the increased ratio would make a more noticable difference on a stock cam with a stock head than people realize because the stock cam is so dinky. A larger aftermarket cam is probably already getting close to if it not exceeding the practical flow of the stock head so it doesn't help much more. Enough difference to notice seat of the pants power though still surprises me. I was trying to chalk that up to the tune but it sounds like he had already put more timing into it before the RRs as well. I run 1.65 ratio RRs myself but have a lot else going on so it's not apples to apples.
Full roller rockers would net no significant power differences in something making the power of a 4.0. IIRC the guys on engine masters showed no power change from a stamp steel rocker vs full roller rocker on a 500 hp engine.
Different platforms have different results. Some gains can be had simply from a lack of deflection in the stock stamped rockers at higher rpms in some applications. I think I remember seeing a 4.0 dyno shoot out showing just that somewhere. I'll see if I can dig it up.
 
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Just finished installing a set of Harland Sharp roller rocker arms. Here is a comparison vs stock.

Can’t tell if there’s any power increase but engine is definitely quieter and seems smoother although that may be because of the sound.

Also like to give a shout out to Harland Sharp. I dropped one of the rocker fulcrums somewhere in the engine bay and just could not find it. Called them and they had two sent to me in a few days no charge!

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Did you have to cut the baffle out of the Valve Cover to make them fit?.. There's a debate whether doing this will foul the PCV valves.
 
Everything from noises to valves kissing pistons in the chamber of love
As long as this thread got brought back from the dead, our 4.0L's are non-interference, so this shouldn't ever happen.