Sealed power/ Harland Sharp Rockers

Old April 2nd, 2019, 12:53 AM
  #1  
Registered User
Thread Starter
 
Join Date: Nov 2011
Location: Ste Rose Manitoba Canada
Posts: 405
Sealed power/ Harland Sharp Rockers

Hello olds family,
What are your thoughts of flat top sealed power pistons and harland sharp rockers for iron heads?
Pros/Cons??
Thanks
Kyle's77cutlass is offline  
Old April 2nd, 2019, 06:44 AM
  #2  
Registered User
 
Join Date: Sep 2011
Location: Plano, TX
Posts: 1,079
All depends on what you're doing.
The HS stuff, especially part 5016, is very nice. But, the roller tip comp cams rockers will get you 90% of what most folks need. You just have to throw away comp's pinch nuts and pushrods.
oddball is offline  
Old April 2nd, 2019, 07:10 AM
  #3  
Registered User
Thread Starter
 
Join Date: Nov 2011
Location: Ste Rose Manitoba Canada
Posts: 405
A brand new set of 5001 came up for sale, just wondering if worth to snag.
Looking at a 350 build soon, but nothing radical
Kyle's77cutlass is offline  
Old April 3rd, 2019, 06:54 AM
  #4  
Registered User
 
Join Date: Sep 2011
Location: Plano, TX
Posts: 1,079
5001's work for moderate lift cams. The geometry is based on the Ford rocker which *tends to be* OK for Olds. If it's a screaming deal then sure.
5016 is the actual Olds 1.6:1 design.

The apples-to-apples cost comparison is:
HS rockers + guide plates + pushrods + studs
Comp roller tip kit + polylocks + pushrods

To be clear, I think the HS stuff is exceptional and I run the 5016's in my 403. But I used the comp kit in all my prior builds.

As for pistons, Sealed Power makes perfectly acceptable stuff. It all depends on what you want to do and what makes sense for your combo. Piston configuration (material, ring pack, weight, dish size, etc) matters more than specific manufacturer. I'd expect the Sealed Power designs are pretty old, but that's perfectly OK for a mild build. There's not much exciting happening in the world of the small blocks except for what Mark (cutlassefi) is helping bring to market. If you want to get fancy then work with Mark to get a custom piston with a modern ring package. If you want a simpler build then just grab whatever off the shelf fits what you want to do.
oddball is offline  
Old April 3rd, 2019, 12:44 PM
  #5  
Registered User
Thread Starter
 
Join Date: Nov 2011
Location: Ste Rose Manitoba Canada
Posts: 405
Wow, thanks for the information. I just purchased an 1980 442 for my son. It's his last year in school coming up, needs something different then the normal crap at school now adays.
So yes, this is a mild build. Is a spare 350 with the car, which is getting rebuilt, 73 block. Sending block in, punching 30 over, true deck and heads, align hone mains. Touch crank if need.
I have a set of 7a's at home, doing a mild port on them. Looking at a lunati cam set. Cam, lifters,springs and timing chain. Nothing big, something to make a tad rough idle. Need to keep the vacuum.
See a portosonic forsale, going to do some research on them. GM HEI distributor, performance curve done to it
Came across a set of L2320F seal power flat top pistons, he recommends total seal rings.
Unsure of the rockers, thinking of comp roller tips.
Found a pair of NOS Olds/Holley covers, seems comp make rollers that fit under standard size covers. And of course, headers are going in.
If need, will put a stall. Engine is out, so easy to change. 2.73 gears, think will be putting 3.42
Kyle's77cutlass is offline  
Old April 3rd, 2019, 07:16 PM
  #6  
Chevy budget Olds powered
 
coppercutlass's Avatar
 
Join Date: Jul 2011
Location: Elgin, Illinois
Posts: 7,566
The sealed power flat tops work but for a few more bucks you can get a much better , lighter pistons what will make more power.

Now as for the rocker arms. I have been running the PRW stainless steel 1.6 rocker arms for a ford 302 . No issues have had a few sets on various engines including a ford I built recently lol. I bought them on ebay for 120 bucks . Just FWIW. I have been spinning my new 355 to 7k on a few test hits at the shop lot and have been beating on it on the street a bit shaking the new combo out. My last combo I ran the same PRW rocker arms with no issues but was only spinning it to 6300 rpm ( that engine had speed pro flat tops)
coppercutlass is offline  
Old April 3rd, 2019, 08:09 PM
  #7  
Registered User
 
Fun71's Avatar
 
Join Date: Feb 2013
Location: Phoenix, AZ
Posts: 6,540
Make sure those valve covers fit with the accessory brackets. Some are too tall and have clearance issues.
Fun71 is offline  
Old April 3rd, 2019, 08:50 PM
  #8  
Registered User
Thread Starter
 
Join Date: Nov 2011
Location: Ste Rose Manitoba Canada
Posts: 405
Originally Posted by coppercutlass View Post
The sealed power flat tops work but for a few more bucks you can get a much better , lighter pistons what will make more power.

Now as for the rocker arms. I have been running the PRW stainless steel 1.6 rocker arms for a ford 302 . No issues have had a few sets on various engines including a ford I built recently lol. I bought them on ebay for 120 bucks . Just FWIW. I have been spinning my new 355 to 7k on a few test hits at the shop lot and have been beating on it on the street a bit shaking the new combo out. My last combo I ran the same PRW rocker arms with no issues but was only spinning it to 6300 rpm ( that engine had speed pro flat tops)
Build is for my son, so he dont need that much power. Freshen up a 350 with a bit of punch will be good for his first car.
The sealed power were decent price. 350 CND
The PRW fit under stock height covers?
Kyle's77cutlass is offline  
Old April 3rd, 2019, 08:51 PM
  #9  
Registered User
Thread Starter
 
Join Date: Nov 2011
Location: Ste Rose Manitoba Canada
Posts: 405
Originally Posted by Fun71 View Post
Make sure those valve covers fit with the accessory brackets. Some are too tall and have clearance issues.
Okay thanks for the tip
Kyle's77cutlass is offline  
Old April 3rd, 2019, 09:53 PM
  #10  
Chevy budget Olds powered
 
coppercutlass's Avatar
 
Join Date: Jul 2011
Location: Elgin, Illinois
Posts: 7,566
My last 355 was mild and ran 12.20's and it was nothing fancy. My old basic 350 ran 13.7's in the 1/4 mile with mostly stock components. The right work in the right places pays off. Your son is gonna have a hard time keeping tread on them tires lol. As for the Prw's fitting stock covers I dont know. I always have ran the tall moroso valve covers.

Last edited by coppercutlass; April 3rd, 2019 at 09:55 PM.
coppercutlass is offline  
Old April 4th, 2019, 07:27 AM
  #11  
Registered User
 
Join Date: Sep 2011
Location: Plano, TX
Posts: 1,079
The rockers don't interfere with the covers under most circumstances. The polylocks cause problems first. Get the short 1" polylocks.

I run the Oldsmobile stamped covers which are smaller in the corners, so I run a 3/8" spacer and a thick metal/rubber gasket. Still fits under the A/C bracket. Standard valve covers won't have any problem. Use a thick gasket for insurance.
oddball is offline  
Old April 4th, 2019, 07:54 AM
  #12  
Registered User
 
Join Date: Feb 2009
Posts: 1,989
You don't need the expensive roller rockers for a mild build - they don't add horsepower.

The Comp roller tips are perfect for a mild build.

There is a video on Motor Trend TV that has a dyno test of all types of rockers.

You would be surprised at the outcome.
My442 is offline  
Old April 4th, 2019, 09:40 PM
  #13  
Registered User
Thread Starter
 
Join Date: Nov 2011
Location: Ste Rose Manitoba Canada
Posts: 405
Originally Posted by My442 View Post
You don't need the expensive roller rockers for a mild build - they don't add horsepower.

The Comp roller tips are perfect for a mild build.

There is a video on Motor Trend TV that has a dyno test of all types of rockers.

You would be surprised at the outcome.
Awesome. Thanks, will check it out.
Kyle's77cutlass is offline  
Old April 6th, 2019, 09:02 PM
  #14  
Registered User
 
olds 307 and 403's Avatar
 
Join Date: Dec 2006
Location: Melville, Saskatchewan
Posts: 4,863
What Octane are you planning on running? You could end up at 10+ to 1 compression.
olds 307 and 403 is offline  
Old April 6th, 2019, 09:54 PM
  #15  
Registered User
Thread Starter
 
Join Date: Nov 2011
Location: Ste Rose Manitoba Canada
Posts: 405
Thought 87, but I guess will be 91 or unless can put thicker head gaskets
Kyle's77cutlass is offline  
Old April 6th, 2019, 11:14 PM
  #16  
Chevy budget Olds powered
 
coppercutlass's Avatar
 
Join Date: Jul 2011
Location: Elgin, Illinois
Posts: 7,566
My last 350 with a .030 over bore .025 piston to deck height clearance, .040 head gaskets and my #6 heads milled .024 i had 9.97 to 1 compression. With the flattops
coppercutlass is offline  
Old April 7th, 2019, 04:28 AM
  #17  
Registered User
Thread Starter
 
Join Date: Nov 2011
Location: Ste Rose Manitoba Canada
Posts: 405
What did you run for fuel?
Kyle's77cutlass is offline  
Old April 7th, 2019, 12:33 PM
  #18  
Chevy budget Olds powered
 
coppercutlass's Avatar
 
Join Date: Jul 2011
Location: Elgin, Illinois
Posts: 7,566
Depnding on the day and what I was doing. 91 would be fine for the daily usage with a good tune. If i was racing and making the drive to the track and back ., 93 octane. On some occasions on hot days i would get some light pinging coming off a stop light usually after a long day at the drag strip with the engine being heat soaked. I'm currently running 10.25 to 1 compression on iron heads but the chambers are polished and that helps keep hot spots down. Still running 93 octane.
coppercutlass is offline  
Old April 7th, 2019, 12:53 PM
  #19  
Registered User
 
olds 307 and 403's Avatar
 
Join Date: Dec 2006
Location: Melville, Saskatchewan
Posts: 4,863
Get the LF2321 6cc dish forged pistons or even better the 10cc Mahle forged pistons in the 4.065" oversize, if the block will clean up with a hone at the machine shop. If it needs an overbore, then get the 4.100" oversize. They will also be less in the hole than the Sealed Power/Speedpro forged pistons, much lighter and a way more modern ring pack.
olds 307 and 403 is offline  
Old April 7th, 2019, 01:03 PM
  #20  
Chevy budget Olds powered
 
coppercutlass's Avatar
 
Join Date: Jul 2011
Location: Elgin, Illinois
Posts: 7,566
I belive price and availability was the reason he was doing the speed pro flat tops.
coppercutlass is offline  
Old April 7th, 2019, 04:01 PM
  #21  
Registered User
Thread Starter
 
Join Date: Nov 2011
Location: Ste Rose Manitoba Canada
Posts: 405
The car is for my son, his last year in high school.
So nothing too special. Found sealed power pistons 30 over for cheap. I have a set of 7a's, will do a mild port on them. Thinking of an edlebrock intake. Lunati cam set, nothing nuts. Want to keep vacuum.
Block will be punched 30 over, align hone,true the deck and block.
Kyle's77cutlass is offline  
Old April 7th, 2019, 04:03 PM
  #22  
Registered User
Thread Starter
 
Join Date: Nov 2011
Location: Ste Rose Manitoba Canada
Posts: 405
My build will be different, that's the motor I will put money into
Kyle's77cutlass is offline  
Old April 8th, 2019, 10:38 AM
  #23  
Registered User
Thread Starter
 
Join Date: Nov 2011
Location: Ste Rose Manitoba Canada
Posts: 405
Dumping this thread, making a new 1
Kyle's77cutlass is offline  
Old April 8th, 2019, 10:55 AM
  #24  
Registered User
Thread Starter
 
Join Date: Nov 2011
Location: Ste Rose Manitoba Canada
Posts: 405
Started new thread in small blocks
Kyle's77cutlass is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Stevec
Big Blocks
4
April 11th, 2012 01:04 PM
bosch 68 442
Big Blocks
3
June 29th, 2011 05:02 PM
70OLDS442
Big Blocks
0
November 21st, 2007 05:00 PM


Thread Tools
Search this Thread
Quick Reply: Sealed power/ Harland Sharp Rockers


Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.