I have a 5.2 with a compcam 20-744-9
What performance changes would I notice if I put in some 1.7 roller rockers? I already have upgraded springs, etc.. and I know I would likely need different valve covers.

Already done:
4:56 gears, kegger mod, aluminum plenum, throttle body mod, headers, full dual exhaust without cats.

I have a lot of weight, so my acceleration is bad. Will the 1.7's improve that?

Thanks.

 

They will make your engine think the cam is bigger than it really is. Valve lift will jump to .510, duration at .050 will also be longer. So, more air in, more air out..... On a stock motor, just adding the rockers gets right around 10HP/TQ.... on an already modified motor.... Anyone's guess.

I think the biggest thing to pay attention to would be valvetrain geometry... don't want the rockers running off the edge of the valve stem.... but, it is basically a 'stock type' cam.... So, should be golden.

I would be real tempted to do the work, and get the adjustable fellers......

 

You won't notice anything from the rockers being changed out. usually you want to let your cam handle the lift and keep the same ratio rockers. And Heyyou is right, with a non stock cam best to spend the extra hundo and get adjustables. Get the pedestal type that adjust over the push rod, not the chevy style that require guide plates. The stock valve covers will fit just fine, may need to bend the baffle up a little higher with a 2x4 or what have you.

 

I appreciate both of your input. I'm seeing a huge price difference between adjustable and non-adjustable. I see harman sharp for around 400, and then 1300 for adjustable. Is that right?

 

Way too much. Here they are for under 500.00.

 

This https://shanonsengineering.com/ is the cheapest place I've seen them(they also have an ebay store http://www.ebay.com/itm/5-2-5-9-DODGE-MAGNUM-V8-HARLAND-SHARP-STUD-MOUNT-ROLLER-ROCKERS/291571566902?_trksid=p2047675.c100005.m1851&_trkparms=aid%3D222007%26algo%3DSIC.MBE%26ao%3D1%26asc%3D39850%26meid%3D429f7202616140b2bf40ac1a56536e31%26pid%3D100005%26rk%3D1%26rkt%3D6%26sd%3D291770048617 ), friend just got the 1.6 adjustable for his Dakota from them for $307 shipped

 

Thank you both. I saw the ebay store from that person, and saw those are listed as non-adjustable, but I also see they can get anything so I will email them . I assumed all the Harland Sharp were non adjustable, but I see the difference in the link from Hey You.

Followup question: Is there anything else I need to buy with these? I see mentions of guide plates, 3/8" studs, etc...

I have aftermaket odessa heads with the following:

Mopar performance Spring P5249464

Melling pushrods MPR-462


Mopar valve spring retainers P4452032

 

No not the type of rocker with guideplates and studs. Get only the pedestal style rocker. There are two different adjustables. One that adjust in the center and the other adjust over the pushrod.
http://stores.hi-potek.com/harland-sharp-1-6-roller-rocker-5-16-bolt-pedestal-mount-adjustable-5-2-5-9-dodge-magnum/

Edit: my mistake, there's only one type of adjustable pedestal rocker, adjuster over pushrod. Stay away from rockers that use guide plates, they are tricky to align to, require hardened pushrods. The pedestal mount rockers are paired with a pin between them to keep them aligned.