This was one of those, "well... yeah." videos. That six into one header really made that old Jeep motor sound good.

Not much of a surprise but the 10% increase is more than I would have predicted. Another advantage to rollers, I believe, is that the engine has better throttle response in addition to more total torque and hp.

In Argentina we have a heavily developed Cherokee engine (with less stroke and more bore), that we use to power the Torinos and GTXs in our top racing series: TC (Turismo Carretera). It uses a dry sump lubrication system, 2 Weber IDF 48-48 carbs, and develops 460 BHP, revving until it gets to 9000 rpm.

I love big inline 6 cylinder engines, they just sound cool and that jeep motor sounded awesome. Super informational video,Thanks.

Been waiting for this to come out, looking for more more ways to blow money on my I6

I wish I would've seen this before I replaced my valve cover gasket. I'm sure the difference in power and torque is insignificant on a stock engine, but the other benefits are worth the price. Can you test 1.7:1 roller rockers with a stock camshaft?

1966 289-solid lifter, hipo cam, roller rockers! VERY NICE!

Good video! You just talked me out of roller rockers for my Corvair. The ones I was considering only had a roller tip, but still had a half ball pivot, which is where most of the friction losses are.. Not enough power gain to justify the cost. TYVM!

I would say between the net gain in HP and torque and less heat, wear and stress it’s worth the extra $$$.

Nothing beats real world dyno testing!

Good info. Putting theses on my 98 5.9 Cherokee this weekend

Excellent comparison video, thank you!

That's more than I would have thought.

I'd love to see a stock 4.0 compared to a 1.65 or 1.7 roller rocker.

Great job guys. Very good info.

You should have had them do that test with fuel injectors 30lb injectors instead of a carburetor

When I'm 5 hours from pavement in Death Valley NP. A place where water is much easier to find than gasoline. "If you know what you are looking for." A place where there is only 4 gas stations, to cover more than 3.4 million acres. With nearly 1000 miles of mostly unpaved roads. Not to mention all the BLM and Forest Service Land that surrounds it, that also have no gas stations. I will be happy to install anything that conserves fuel. 10 horse power, that's fuel that didn't go out the tailpipe! $350 doesn't seem like a lot of money to me.

These engine builders at Newcomer are so damn good i am gonna buy a Jeep! These motors are bad to the bone smooth torque monsters. Bring back the straight 8

Always like these comparison vid's

Great Info, plan to use it!! Thanks!

nice setup

That's stunning, I always thought rocker deflection didn't happen until higher revs! This is the most surprising lesson learned I've ever had. And exactly what he Said, it's money well spent!

Great video, and really nice job narrating. 👍👍👍

Another informative video, make one someday on a 2.5, keepum comin!!

Thank you for an informative test.

Please more videos covering these jeep stroker motors!

I've been running Sharp's rollers for over 40 years now on a lot of different type engines with absolutely no failures & always saw HP gains. I also use them on my BBC Chevy motor home in the 1.8 ratio to provide .040 inch increased lift. Yes you CAN feel the difference!

Those same gains can be had on a modified 5.7L SBC engine that runs street or strip. Mine did on the dyno. Extensive Head porting , a good set of competition shorty headers and a good camshaft profile can all work together to free up a bunch of extra horsepower and torque. It ended up being a lot of extra bang for the buck. Also running your pistons to zero deck height seems to really wake up engines since it greatly affects the quench area in the combustion chamber. The head gasket is then the only thing that determines what your piston to head clearance will end up being.

Wow!!! What a lesson !! Thanks

EXCELLENT,USABLE INFO...thanks for great vid

Yeah man it's cool like the setup

Love Keiths input!

Test the bronze bushing trunnion vs the needle bearing trunnion. I've heard stories of the needles coming out the rocker arms and doing bad things to the internals.

Your videos always hold my attention. I’m interested in what kind of fuel is being used.

Thank you for the test. It would be nice if you could show the results of different rocker ratios.

My 4.0 isn't running right currently. I'd love this in it's place!

Thanks for sharing !

The reduced friction is a given, overall stiffness gain I am not so sure about when using low pressure valve springs......I have done some testing on rockers plotting the lift curve vs. crank rotation and the stamped rockers can have an exaggerated progressive/degressive ratio if you will and the roller rockers can provide a lift curve cycle that provides more valve open area/time. I suspect that is part of what is happening here......1.6 ratio rockers can be many different ratios throughout the lift curve......only way to know what you have is to degree and plot out the lift curve cycle to compare them. Very nice job on the build on this engine ....It is making really good power, more than I thought it would. Good work guys. Are there any flow numbers from the head?

Thanks!!!

Your videos are freaking AWSOME!!! Thank you very much for your content. I’m like a sponge

Need more vids of comparing same kind of parts . People can see why some parts are more expensive than others . Great vid . 👍

Always interesting with tests like these. Some other tests show no improvement with roller rockers. So it seems it too is case specific just like with exhaust headers..

When you use roller rocker arms with the correct Geometry it reduces side load on the valves it requires extra work. That looks like a cool jeep engine also.

Well done. That is a much bigger difference than I would have figured.

Cool! Have you guys done a test comparing the stock 91'-98' 4.0 HO intake (log intake) vs the stock 99'-06' 4.0 HO intake (horseshoe intake)?

Sounds great

Basically there was another show that tested actual ratio of factory rockers on old and new vehicles alike... A 1.5 ratio rocker usually had a ratio of 1.3-1.4 and a 1.6 ratio rocker usually had a ratio of 1.35-1.5... So even going to a roller rocker 1.6 from a reputable rocker manufacter where 1.6==1.6 ratio you will gain over a factory 1.6 so it's not due to friction losses. And in the case of going from a factory 1.5 ratio which might be 1.34 or something to a true 1.60 you just gained .26 in rocker ratio or 15% more lift at the valve! This is where the power is, and in this 10% increase situation where the torque curve is elevated throughout this is exactly what is going on.

dam i often wondered about roller rocks

What are your thoughts on the 1.7 ratio Harland sharp roller rockers? Would be cool to see if those increase power over the 1.6.

Great video.

Good information 👌🏽

Awesome...Thanks...

I would love to see the turbo Jeep Six dyno test, I bet it's wicked. Also watch the Long Rod VS Short Rod test on Engine Masters that just came out. There is so little difference that it makes no difference.

Great video!!! 🤟🤟 ARP rocker studs might not hurt, but a longer exhaust duration on the cam would definitely help the head breathe.

Now you need roller lifters. Test engines were built with them circa 89 or 90 iirc. As far as the stock rocker arms go. Prior to 1988 or 89 they were stamped in house with a very meticulous die maintenance program. There was one die maker who's full time responsibility was working on the parts for the transfer die used in these parts. Particularly the punches used to form the seat for the rocker arm bearing. Prior to '73 or '74 the AMC six used a shaft mounted rocker arm assembly. After the press room at Kenosha was shut down these parts were out sourced. In terms of the roller rockers. Would it help of the pushrod end had the seat closer to the cam. This would allow a shorter pushrod which should always be a good thing in an OHV engine. Or would it cause an issue with pushrod angles. The 4.0 could really benefit from a better head design. It might be a question of market* size but with modern ignition technology it sould be possible to design and build a good flowing cross flow head with the intake on the distributor side of the block. Development of their inline sixes is something the US manufactures really dropped the ball on. Built as standard economy engines I suppose V-8s were the easy way out. Pontiac tried but the bean counters shut that down. It is my understanding that OHC experimental versions of the 232 were built in the 60s. But didnt go anywhere do to cost issues. The test mules or mule most likely used a camshaft assembly simply bolted to the top of the head. *Edlebrock's aluminum head really couldn't stay too far due to CARB requirements for aftermarket parts intended for street use.

great vid!!!

Wild 6👍

Hey men great channel and great presentation I am a ford guy and would like and love to see a video on a street able ford 300 6 cylinder with a mild turbo

Engine masters did this but they used roller rockers with a greater ratio than the stockers which means the valves got more lift. I always knew less friction means more power can be put to useful work but the question is, how much? The engine Masters test did not answer that question. Yes, they got more power but how much of it was by the valves getting more lift? Your test was was genuine and answered the question as asked, not with an unknown factor thrown in. Well done.

Great video and I have personally done similar dyno tests. The end result is always the same. Great job guys. The hard part is convincing the customer.

More consistent then stamped. Someone did a comparison of stock 1.5 ratio chevy rockers and seen a variance of +/- .03. Also less drag and free up power.

surely you have a dial indicator. put it on a retainer and test the valve lift for deflection between steel and aluminum.

Love these 6 cyl vids, I got 3 of them

Looks like the H.O. is still a better head

Great breakdown of the separate parts changes and their power implications.

Thinking about getting some roller rockers for my tired 3.1 v6 buick century. If they do less wear and stress on the motor then sounds like a good way to get more life out of it. At 233k now.

The power loss is ONLY from the less accurate amount of rocker ratio. Stamped rockers never measure there full ratio. So if 1.6 stock. If you check the ratio I'd bet you'd find the stamped ones less than that around 1.55 or so. Not a friction loss. I've seen a few others tests like this. One using a stamped rocker and then machined to the right ratio check against roller rockers and there was no power gain

From testing an average of five HP. Anything that reduces friction and increases valve train accuracy is worth it. I imagine GM went to a roller rocker type system on the LS engines for a reason.

This test at best is inconclusive, you need to measure the lift at the valve with both rockers to verify that they both produce the same lift, often times stock rockers don't live up to their advertised ratio

This has opened my eyes big time. I currently working on a K20a all motor. I'm looking for aftermarket roller rockers that will make my engine rev to 10K safely. I did not know it could possibly gain power out of it as well. Problem is, all after market rollers eliminates Vtec which is what I'm not trying to do. Anyway, keep the videos coming. Love them.

Not to mention valve guide wear

You just sold sets of roller rockers.

Makes me wonder how much difference roller cam bearings would make.

I have to rebuild my stroker. I always drooled over the yella terra rrs.

I'm at 46 seconds in and i acknowledge that Truth in fact is YES roller rockers associate the geometric adaptations intercourse longer push-rod and freeing up most frictionless assembly.. (in my humble opinion)

Maybe you should consider investegating how the rocker arm ratio varies throug the lift range? A 1.6:1 rocker arm does not increase lobelift 1.6 times from 0.006 lifter rise to peak lift. More people should talk way more about this. :)

I know you guys are talking about horsepower and torque on the little 4.0 would you guys be willing to do a comparison a four barrel TBI versus a two barrel TBI. I’m curious to with the horse Power and torque curve would be

need a test of roller tip vs full roller.

The Harland sharp rockers are also much lighter than comparable aluminum rr's, I saw a comparison where they weighed several different ones and the Harland Sharp one's weighed up to 60 grams less EACH.

Is it friction loss or inconsistency with the rockers?

I am curious, what is the delta in heat generated in the engine between the stock sheetmetal rockers and the rollers? I mean, you say it helps in the video, and other commentators have also said as such, but...what is that difference? I don't think I have ever seen anyone demonstrate the difference with actually measured results.

Looks like a stacked deck

do you have any dyno tests on diesel motors? Looking for 10,000 lbs farm tractor class. Thanks

That was perfect, excellent intro, narrating and testing... then as I wondered what the cost for the gain in performance was, you gave it. You guys rock.

ok, now lets mix ratios between intake and exhaust

What kind of results would I get with these lifters on a 1998 stock 4.0?

This test has been done many many times, the results are always about the same, and people continue to think roller rockers are a waste of money. As mentioned below, much comes down to stamped rockers being very inconsistent in size, not simply reduced friction.

Interesting video. Hopefully you build a dodge 3.9 V6 someday. Has potential.

I’ve worked at Harland Sharp for 20+ years. I’m bias but our stuff is the best. 100% domestic materials and manufacturing right here in the USA 🇺🇸 Thanks for making this video.

Here the thing i was told by some engine builders who no way more then me , if you were to take the stock stamped rockers and mic them they are all over the board factory imperfections , which throw all the # uneven ,causing most of the hp loss , this was on bbc and under 6000k ish rpm

Sold

Any idea what difference these would make on a stock 190hp 4.0 ?

I believe the power gain from the rollers is from the adjustable feature more than the friction aspect with these light beehives. In fact the way to disprove my contention would be to use adjustable pushrods on the stamped rockers. Almost all other vids I've ever seen bar this one, show rollers make hardly any difference. Of course rollers are so much better it is ridiculous esp when using aftermarket camshafts and you'd never ever use stamped in a .575"+ lift camshaft but yeah... I'd like to see a bit of user dialled preload on those stamped arms. There is always the possibility that stock Jeep rockers are worse than any other brand for flex but they look more sturdy than Chevy stamped to my eye.

I've got some Harland Sharp adjustable rollers, but haven't found any references on proper adjustment. if anyone has a link to setting them up on a 4.0, can you share? Thx

Flat lifters or roller lifters. How much power is gained?

What CFM did the head flow?

Good

So...there's no need for a stiffer spring "upgrade" for sub 400 Hp inline six's? Seems like anything under 5k rpm's, there's less worry about valve float?

Honestly I've been waiting to see a pro and con video, but I've always been curious about the Boosted Technologies sidemount supercharger with the billet intake vs a Borg Warner EFR 9180 twin scroll .80/1.05 turbine housing. Then to see it on a stock vs 4.6 or 4.7 stroker, But that's just me.

..If the power would of shown up toward the end of the pull when friction is at the highest, but it didn't.. the power curve is parallel across the rpm range. the rollers have a higher Ratio than the stamp steel. Put a dial gauge on it.