TPI Tuned Port Injection discussion and questions. LB9 and L98 tech, porting, tuning, and bolt-on aftermarket products.
Sponsored by:
Sponsored by:

Roller Rocker Arms and HP Gains?

Thread Tools
 
Search this Thread
 
Old Jan 29, 2008 | 12:59 PM
  #1  
BC GTA's Avatar
Thread Starter
Member
 
Joined: Nov 2003
Posts: 388
Likes: 0
From: Victoria, British Columbia
Car: 1989 GTA
Engine: 5.0 TPI
Transmission: T-5 WC
Axle/Gears: Yukon 3.73
Roller Rocker Arms and HP Gains?

I did a search on this topic and did not find an answer to this question except for a stock engine.

I have a 5.0 liter TPI engine with a Comp Cam cam, headers, etc. The cam raises gross valve lift to about .480" on both the intake and exhaust. I currently have stock 1.50 rocker arms. If I went to 1.50 full roller rockers would I gain much HP. Comp Cam advised that I can not to 1.60 due to the pressed in studs and problems with springs.
Reply
Old Jan 29, 2008 | 01:04 PM
  #2  
mnorton's Avatar
Senior Member
20 Year Member
 
Joined: May 2002
Posts: 845
Likes: 0
From: Northern California, Redding
Car: Red 1987 IROC Convertible
Engine: 305 LB9 TPI
Transmission: T5 5-Speed
Axle/Gears: 9-Bolt 3.45
Re: Roller Rocker Arms and HP Gains?

About a 5 HP gain.
Reply
Old Jan 29, 2008 | 01:04 PM
  #3  
Apeiron's Avatar
Moderator
 
Joined: Jan 2000
Posts: 20,981
Likes: 11
From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Re: Roller Rocker Arms and HP Gains?

You'd see almost no HP increase.
Reply
Old Jan 29, 2008 | 01:37 PM
  #4  
8T9 BANDIT's Avatar
Banned
 
Joined: Jan 2007
Posts: 1,088
Likes: 0
From: NYTHIRDGEN
Car: 1989 T/A
Engine: PROCHARGED LB9
Transmission: FB BUILT 700r4 2200 stall
Axle/Gears: 10 BOLT EATON 3:73 POSI
Re: Roller Rocker Arms and HP Gains?

get a good set of 1.6rr's, new springs and a shim kit. then u should see some gains.
Reply
Old Jan 29, 2008 | 03:29 PM
  #5  
TPeye's Avatar
Member
20 Year Member
 
Joined: May 2004
Posts: 197
Likes: 0
From: New York
Car: 1992 Camaro Z28
Engine: 350ci
Re: Roller Rocker Arms and HP Gains?

With 1.6 rockers you may have to open up the push rod holes in the heads to avoid clearance problems. You might consider using 1.6 on the intake side and 1.5 on the exhaust, because the higher exhaust lift doesn't really make a difference.
Reply
Old Jan 29, 2008 | 05:12 PM
  #6  
Dale's Avatar
TGO Supporter
iTrader: (12)
 
Joined: Jun 2002
Posts: 6,819
Likes: 3
From: AR
Car: 1991 Camaro RS Vert
Engine: 350 S-TPI
Transmission: T5
Axle/Gears: GU5/G80/J65
Re: Roller Rocker Arms and HP Gains?

On another chat board I attend they dyno there cars every year. In the past year a guy had installed roller rockers and something else. It netted him nothing. However, you should beable to rev the engine a bit faster.
Reply
Old Jan 30, 2008 | 01:11 PM
  #7  
BC GTA's Avatar
Thread Starter
Member
 
Joined: Nov 2003
Posts: 388
Likes: 0
From: Victoria, British Columbia
Car: 1989 GTA
Engine: 5.0 TPI
Transmission: T-5 WC
Axle/Gears: Yukon 3.73
Re: Roller Rocker Arms and HP Gains?

Thank you everyone for your input. A consensus has emerged that this would provide negligible to no HP increases.
Reply
Old Jan 30, 2008 | 06:10 PM
  #8  
SDTransAM's Avatar
Senior Member
iTrader: (5)
 
Joined: Nov 2007
Posts: 529
Likes: 0
From: Rapid City, SD
Car: '83 z/28
Engine: 305
Transmission: T5
Axle/Gears: Stock?
Re: Roller Rocker Arms and HP Gains?

So let me see, I beg to differ, You go from stock 1.5's to 1.6 roller rockers, and your not gonna see any difference? You are gaining lift, plus taking away friction, How are you not going to gain anything? If you have .480 lift with a 1.5 rocker, you are going to have .512 lift with a 1.6 plus it is a roller rocker, hm that should be enough to see some gain right?
----------
Oh, I see, you guys are just comparing a stamped 1.5 rocker to a 1.5 roller rocker? If that's the case, you wouldnt gain much, but you are decreasing friction, and the parts will last longer, and yes maybe rev a little higher a little faster.

Last edited by SDTransAM; Jan 30, 2008 at 06:12 PM. Reason: Automerged Doublepost
Reply
Old Jan 30, 2008 | 06:19 PM
  #9  
Orr89RocZ's Avatar
Supreme Member
20 Year Member
Liked
Loved
Community Favorite
iTrader: (20)
 
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: Roller Rocker Arms and HP Gains?

the only way i can see power gains is if a high rpm motor is experiencing alittle valve float with heavier steel (even tho stock stamped isnt heavy) rocker and goes to a lightweight aluminum rocker arm which enables the springs to control inertia better.

Full roller thing i dont think you'll see much, maybe a few ponies at HIGH rpms but its not worth the upgrade. Just alittle easier on parts i guess.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Hotrodboba400
Firebirds for Sale
3
Dec 10, 2019 07:07 PM
TX-SleeperC5
Firebirds for Sale
25
Feb 24, 2016 01:34 PM
New2Chevy
Engine/Drivetrain/Suspension Parts for Sale
2
Sep 28, 2015 12:35 AM
ericjon262
Engine Swap
7
Sep 11, 2015 06:07 PM
Hotrodboba400
Firebirds for Sale
0
Sep 2, 2015 07:28 PM




All times are GMT -5. The time now is 04:56 PM.