Hydralic lifters with rockers vs mechanical

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tekslk

tekslk

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Is there any kind of advantage on changing rockers to the 273 adjustable ones when using hyd lifters? Someone told me the gyeamtry is diffrent and more lift obtainable out of the mechanical rockers. Any truth to this? Or would it be a wate of time since car runs great now? Im gonna stay with the hyd lifters just possibly change the rockers if its not a waste of time.
 
I'm confused.................

you are not changing lifters? Just the rocker arms?

Here's the deal

You cannot swap solid lifters onto a hydraulic camshaft

You CAN use ADJUSTABLE 273 rockers with a hydraulic cam and lifters, but you'll have to scare up different pushrods because the original mechanical lifters are a different HEIGHT than are hydraulic lifters.

If you are running a big performance cam it might make some difference. If there is reason to believe the original hydraulic setup is "out of spec" you might make some difference.

This would come from an improper valve job, IE improper valve stem height, from milled deck and or heads, and to a minor degree, head gasket thickness
 
not changing lifters, keeping hyd. I just want to change rockers and yes pushrods if there is any gain from it
 
Although you may not notice any power from it, you can tailor the lifter preload much more accurately. Plus, the 273 rockers are ductile iron and much closer in ratio than the stamped rockers. To me, that's worth all the trouble right there.
 
if it runs good leave it alone (imo) unless you step up to some 1.6 rockers. if you have them laying around i guess you could, but i sure wouldn't buy them and plan on seeing anything noticeable. hyd lifters really don't care as long as there happy and not pumping up. now if you were class racing and running big RPM then yes, adj rockers would be a slight advantage to get the rpm. do you race the car?
 
It runs great thats my concern to try to get just a little more or leave my f n hands off it. Im listining to everyone,not sure what way to go yet.
 
I always liked the 273 adjustable rockers with a larger hydraulic cam, not that they are always needed. I always used hi-bleed/anti pump up style lifters in most of the builds I was serious about, even on other brands also. Being able to keep the preload quiet, but at a minimum, was said to add some rpm's to the hyd. setup. Honestly I never did a apples to oranges comparison, i just always went that way and had really good results. As far as the Mopar small block, i never ran one into oblivion, but my neighbors 340 turned 7000 rpm's for years with that setup. Although, it became a bracket only car over time.

You do need a proper length cup style pushrod for the swap, and with a good running engine that shifts at 5500/6000, i probably wouldn't rush out to switch them.
 
If it runs good then I would leave it be. Millions of Mopars ran great with non adjustable valve trains.
 
tekslk said:
It runs great thats my concern to try to get just a little more or leave my f n hands off it. Im listining to everyone,not sure what way to go yet.
Click to expand...


usually listening to people is trouble.. lol

what cam are you running, lift?
 
Just bought them The push rods are coming with the rockers. Maybe over christmas when I have some time off I will change them just for ***** and giggles. Iam shifting now at 6000 when Im into itand car seams to work great, A machinest said the adjustable ones will let the valve lift further because of the angle. Is this bull or what?
 
not enough to screw with , draw a str8 line 6 inckes long now angle 1 about 3 degree's then messure the over all line and draw it str8 it will give you that much more just as an example if it was a 1/4 inch it would be worth it like some 1 said with the 1.6 rockers you could get almost .300 more lift but your hydrolics will suck that to .127 or an 1/8 inch lift don't mess with it if not trying for a speed or time record ,sit back smile and waive back YAH ITS MY MOPAR AND I AM PROUD OF IT
 
I have a comp cam 494 lift cant remember the rest of the specs. Im using a built 2200 stahl converter and 355 gears. Machinest said im probably getting like a 460 lift with the hyd rockers.???
 
should be more than a few hours tops to switch everything over if the pushrods you have coming are the right length. yes you will probably see a little more lift at the valve with the adj rockers depending, stamped ones arn't know for ratio accuracy. but with a hyd cam its kind of hard to measure without using a solid lifter for checking purposes. your cam is getting up in the lift range that a better rocker isn't a bad idea. still wouldn't hold my breath that you'll see much or anything of a power increase. but it never hurts to try!! lol
 
That's half the fun,trying different things and a great way to learn.
You will have to follow the correct procedure and adjust each one correctly.
There are gains,and it should be a stronger set up
 
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