C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

Dumb Roller Rocker Question

Thread Tools
 
Search this Thread
 
Old Jan 8, 2006 | 07:05 PM
  #1  
Hogan's Avatar
Hogan
Thread Starter
Race Director
15 Year Member
 
Joined: Nov 2002
Posts: 19,149
Likes: 2
From: First to Sign Grumpy's Hat Only 53 miles from Hell
St. Jude Donor '06-'09-'10-'11
Default Dumb Roller Rocker Question

Once I obtain steady employment I would like to get some roller rockers. I was thinking about getting 1.6's or the max I could go on my LT1 but I was thinking of staggering the ratio, as in 1.6 on the intake and 1.65's or 1.7's for the exhaust. A few years ago I remember a couple of Pontiac guys were running 1.6 on the intake and 1.7 on the exhaust to improve flow. I know the Pontiac heads did not flow as well as a SBC head but would this trick help??
Reply
Old Jan 8, 2006 | 07:17 PM
  #2  
Nathan Plemons's Avatar
Nathan Plemons
Race Director
15 Year Member
 
Joined: May 2001
Posts: 14,165
Likes: 9
Default

Personally I'd go with 1.7's on both if you're going to go with 1.7's at all. The LT1 heads should benefit by the added lift on both sides.
Reply
Old Jan 8, 2006 | 07:28 PM
  #3  
Hogan's Avatar
Hogan
Thread Starter
Race Director
15 Year Member
 
Joined: Nov 2002
Posts: 19,149
Likes: 2
From: First to Sign Grumpy's Hat Only 53 miles from Hell
St. Jude Donor '06-'09-'10-'11
Default

Originally Posted by Nathan Plemons
Personally I'd go with 1.7's on both if you're going to go with 1.7's at all. The LT1 heads should benefit by the added lift on both sides.
By going to 1.7's would I have to change out springs and pushrods?
Reply
Old Jan 8, 2006 | 11:51 PM
  #4  
MYCoupe's Avatar
MYCoupe
Melting Slicks
20 Year Member
Liked
Loved
Community Favorite
 
Joined: May 2003
Posts: 3,490
Likes: 68
From: Hewitt NJ
Default

If you're still using the stock springs, then yes you'll have to repace them.
Reply
Old Jan 9, 2006 | 11:07 AM
  #5  
Hogan's Avatar
Hogan
Thread Starter
Race Director
15 Year Member
 
Joined: Nov 2002
Posts: 19,149
Likes: 2
From: First to Sign Grumpy's Hat Only 53 miles from Hell
St. Jude Donor '06-'09-'10-'11
Default

Originally Posted by Admiral94
If you're still using the stock springs, then yes you'll have to repace them.
Ok, what about the push rods if I go with 1.7's?
Reply
Old Jan 9, 2006 | 12:04 PM
  #6  
Nathan Plemons's Avatar
Nathan Plemons
Race Director
15 Year Member
 
Joined: May 2001
Posts: 14,165
Likes: 9
Default

If you're really picky you'll get an adjustable length pushrod and do a bunch of measuring to figure out the exact length that you may need. Being said I've been running 1.7's on my car for over 19k miles without any troubles.
Reply
Old Jan 9, 2006 | 12:42 PM
  #7  
Hogan's Avatar
Hogan
Thread Starter
Race Director
15 Year Member
 
Joined: Nov 2002
Posts: 19,149
Likes: 2
From: First to Sign Grumpy's Hat Only 53 miles from Hell
St. Jude Donor '06-'09-'10-'11
Default

Originally Posted by Nathan Plemons
If you're really picky you'll get an adjustable length pushrod and do a bunch of measuring to figure out the exact length that you may need.

Doesn't CompCams or other companies sell the correct pushrod for such an application?

Bout how much hp do you think 1.7's would pick up? Should there be any tuning afterwards to optimize having the rockers?

Sorry for the dumb questions.
Reply
Old Jan 9, 2006 | 01:29 PM
  #8  
Nathan Plemons's Avatar
Nathan Plemons
Race Director
15 Year Member
 
Joined: May 2001
Posts: 14,165
Likes: 9
Default

Yes several companies sell pushrods of various different lengths, but exactly what you may need depends on your setup. On a rebuild say you had the heads milled and used a thinner head gasket. You might need a shorter pushrod than somebody who has stock heads and stock head gaskets. As such there is absolutely no way that comp cams could keep an accurate list of what exact pushrod you need for what exact configuration.

1.6 rockers on an otherwise stock LT1 are supposed to give you 10-15 RWHP. I don't know that anybody has ever tried 1.7's on a stock LT1 so I really can't quantify a gain for you. The numbers indicate that there should be a gain, but I've never seen data to give a number on it.

FYI it would be highly recommended to change your springs just by going with 1.6's and it will be absolutely required if you go with 1.7's.

Tuning will never hurt and should be considered especially if the car is speed density and doesn't have a MAF sensor.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

10 Ugly Corvettes That We Still Kinda Love

 Joe Kucinski
story-1

Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

 Brett Foote
story-2

10 Things Every Corvette Owner Needs (2026 Edition)

 Michael S. Palmer
story-3

8 Most "Only Corvette Owners Understand" Quirks and Problems

 Pouria Savadkouei
story-4

10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

 Joe Kucinski
story-5

How Much Horsepower Every Corvette Engine "LOST" in 1972

 Joe Kucinski
story-6

Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

 Michael S. Palmer
story-7

Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

 Joe Kucinski
story-8

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-9

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
Old Jan 9, 2006 | 01:44 PM
  #9  
Hogan's Avatar
Hogan
Thread Starter
Race Director
15 Year Member
 
Joined: Nov 2002
Posts: 19,149
Likes: 2
From: First to Sign Grumpy's Hat Only 53 miles from Hell
St. Jude Donor '06-'09-'10-'11
Default

Thanks Nathan for taking the time!!!
Reply
Old Jan 9, 2006 | 01:46 PM
  #10  
Nathan Plemons's Avatar
Nathan Plemons
Race Director
15 Year Member
 
Joined: May 2001
Posts: 14,165
Likes: 9
Default

Hey no problem, I work at a helpdesk. When the phone's not ringing, I'm cruising the forum. I'm either trying to help somebody or arguing

Have you seen my website? Might answer some questions, hell it might raise a few.

http://www.wku.edu/~nathan.plemons/h...rformance.html
Reply

Get notified of new replies

To Dumb Roller Rocker Question





All times are GMT -4. The time now is 04:25 AM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-8
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-9
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE