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

Adding guide plates to use non self aligning rockers on a 91 TPI???

Thread Tools
 
Search this Thread
 
Old 09-07-2016, 09:17 AM
  #1  
Senior Member

Thread Starter
 
raptere's Avatar
 
Join Date: Oct 2002
Location: Northwest Chicago Suburbs
Posts: 522
Received 40 Likes on 34 Posts
Car: 1991 Camaro Z-28, Durango R/T
Engine: 5.7L TPI
Transmission: 700R4
Axle/Gears: 3.23
Adding guide plates to use non self aligning rockers on a 91 TPI???

Hey all, first post in probably 10 years on here, LOL!

So back when I was in high school I bought some really nice roller rockers, comp cams pro magnum full roller chromo 1.6 ratio rockers. I got push rods at the same time. I had grand plans for the car, such as new heads so I specifically bought the non self aligning rockers for them, but the new heads never happened. Question is, can I just add guide plates to the factory L98 heads to use the non self aligning rockers, or would I be best off trying to sell the rockers here or on ebay and just buy the correct self aligning ones for my heads? If I were to get the guide plates would I also have to get new studs? Would there be any downsides to doing this? Benefits? This is no longer my daily driver, I basically drive it about 50 miles once or twice a week in the summer to and from work and around town. I don't need crazy power but 10 or 15 hp would be way nicer to have than a box of parts taking up space in my garage! Hopefully my sig still has all my engine info, if you need anything else to accurately answer, just ask.

Thanks!
Eli
Old 09-07-2016, 10:41 AM
  #2  
Senior Member
iTrader: (1)
 
greenyone's Avatar
 
Join Date: May 2014
Location: Pittsburgh
Posts: 550
Likes: 0
Received 5 Likes on 5 Posts
Car: 91 G92 Z28
Engine: 305 TPI
Transmission: T5
Axle/Gears: 342
Re: Adding guide plates to use non self aligning rockers on a 91 TPI???

I'd sell them and use that money for something else....like better flowing heads. Roller rockers, even going from 1.5 to 1.6 are probably not going to translate into anything near 10-15 hp to your rear wheels.
Old 09-07-2016, 02:37 PM
  #3  
Senior Member

 
Vanilla Ice's Avatar
 
Join Date: Aug 2002
Location: ARIZONA
Posts: 948
Likes: 0
Received 4 Likes on 4 Posts
Car: 92 Trans Am Conv
Engine: LB9
Transmission: T5
Axle/Gears: 3.08
Re: Adding guide plates to use non self aligning rockers on a 91 TPI???

NSA rockers are too much "trouble" for a TPI. You'll have to invest in guide plates and ideally hardened pushrods. NSA are better for higher RPM which TPI doesn't see.

I say sell them and get some SA rockers, and there is more they do for you than just 10-15whp at peak. They add power across the entire powerband and increase mpg.

Last edited by Vanilla Ice; 09-07-2016 at 02:40 PM.
Old 09-08-2016, 08:42 AM
  #4  
Member

 
topless87's Avatar
 
Join Date: Feb 2009
Location: Independence, Kansas
Posts: 186
Received 3 Likes on 3 Posts
Car: 1987 IROC-Z Convertable
Engine: 305 TPI
Transmission: 5 Speed BW T-5
Axle/Gears: 3.08 Posi
Re: Adding guide plates to use non self aligning rockers on a 91 TPI???

For guide plates you have to mill the old rocker towers down, have them tapped for screw in studs in order to hold the guide plates on. Also, with 1.6 ratio, if you don't have your pushrod geometry correct you end up with "Z" shaped pushrods at some point, ask me how I know...I agree with the others, sell them and put the money to a better performance use unless you are willing to tear the heads off for all of the work needed. MTC
Old 09-08-2016, 10:48 AM
  #5  
Member

iTrader: (5)
 
Steve Mack's Avatar
 
Join Date: Aug 2006
Location: Stafford, Connecticut
Posts: 311
Likes: 0
Received 1 Like on 1 Post
Car: 87 Iroc
Engine: modified 350
Transmission: high performance built 700R4
Axle/Gears: Strange S60 3:73
Re: Adding guide plates to use non self aligning rockers on a 91 TPI???

Look up Professional products They sell a set made by Jomar.They are they are thin and very adaptable.They are not like any other guide plates out there.You will have to use hardened push rods with them.
Old 09-08-2016, 03:06 PM
  #6  
Supreme Member

iTrader: (7)
 
Dyno Don's Avatar
 
Join Date: Mar 2000
Location: Orange, CA
Posts: 5,674
Likes: 0
Received 106 Likes on 65 Posts
Car: '90 Trans Am-12.45@110.71
Engine: 355 w/AFR 195's Elem. 400/430 HP/TQ
Transmission: Tremec T-56
Axle/Gears: 12 Bolt 3.73
Re: Adding guide plates to use non self aligning rockers on a 91 TPI???

First, take off a valve cover and look at the push rod holes.
Some heads came with round holes, some came with oval holes.
If you have oval holes you can use non-SA rockers.
Old 09-10-2016, 03:35 PM
  #7  
Senior Member

Thread Starter
 
raptere's Avatar
 
Join Date: Oct 2002
Location: Northwest Chicago Suburbs
Posts: 522
Received 40 Likes on 34 Posts
Car: 1991 Camaro Z-28, Durango R/T
Engine: 5.7L TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: Adding guide plates to use non self aligning rockers on a 91 TPI???

So getting new heads to accomodate the rockerss would not be an ideal solution any more financially. Even though that was my intention back when I got them.

So am I understanding it right that the factory heads have pressed in studs instead of threaded ones that are generally required for guide plates? I found those jomar guide plates. Are you saying I could use those with my existing heads and studs? I do have hardened rods I ordered at the same time as the rockers, sitting in the same box as the rockers.

I can pull a valve cover and look at my heads. Are you saying heads intended for self aligning rockers had the round holes, or that even though there are no guide plates I could still use the non self alligning rockers with a head with oval holes, even it it was originally installed with self aligning rockers?
Old 04-12-2017, 02:40 PM
  #8  
Senior Member

Thread Starter
 
raptere's Avatar
 
Join Date: Oct 2002
Location: Northwest Chicago Suburbs
Posts: 522
Received 40 Likes on 34 Posts
Car: 1991 Camaro Z-28, Durango R/T
Engine: 5.7L TPI
Transmission: 700R4
Axle/Gears: 3.23
Re: Adding guide plates to use non self aligning rockers on a 91 TPI???

Well, some time has gone by and I've decided to just sell off these rockers and buy some replacement S/A ones.

If anyone is interested there posted here on TGO: https://www.thirdgen.org/forums/engi...-cams-pro.html
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
slow305
Engine/Drivetrain/Suspension Parts for Sale
4
11-12-2017 03:25 PM
MantyZ28
Exterior Parts for Sale
22
04-10-2017 07:07 PM
thewizard
Engine/Drivetrain/Suspension Parts for Sale
14
03-22-2017 02:54 PM
MantyZ28
Interior Parts for Sale
18
11-04-2016 05:13 PM
Finally Got one
Tech / General Engine
3
08-08-2016 01:59 PM



Quick Reply: Adding guide plates to use non self aligning rockers on a 91 TPI???



All times are GMT -5. The time now is 11:51 PM.