Modest Power for my Gen 4 WS6
Thread Starter
Registered User
Joined: Jan 2025
Posts: 1
Likes: 0
Modest Power for my Gen 4 WS6 Hi all, I live in Australia and Ive owned beautiful 99/00 WS6 for 20 yrs, however its engine needs a little work, i.e leaking Hydraulic lifters, rattling Cats and a few oil leaks etc.
Ive decided to use these issues as an opportunity to also boost power conservatively and Im thinking Heads, intake manifold and cam. Ive set a budget of US$2.5-3k
Ive read many sources (incl LS1Tech) that recommend LS6 heads, manifold and cam to be a quick and easy solution to a modest and reliable power increase, however when I go to look (to buy) there are so many options it addles my brain😵💫.
Im therefore looking for suggestions (based on personal experience) not only to the approach but to specific brands/suppliers.
Any help will be gratefully appreciated🙏🏼
Ive decided to use these issues as an opportunity to also boost power conservatively and Im thinking Heads, intake manifold and cam. Ive set a budget of US$2.5-3k
Ive read many sources (incl LS1Tech) that recommend LS6 heads, manifold and cam to be a quick and easy solution to a modest and reliable power increase, however when I go to look (to buy) there are so many options it addles my brain😵💫.
Im therefore looking for suggestions (based on personal experience) not only to the approach but to specific brands/suppliers.
Any help will be gratefully appreciated🙏🏼
TECH Apprentice
Joined: Jun 2004
Posts: 317
Likes: 52
From: Charleston, SC
How firm is your budget? I’d stick with stock 243 heads (with new springs that compliment the cam), a stock LS6 intake, and a mild cam. There are alot of costs associated with a tune, gaskets, bolts, fluids, tools that just add up. You can take a look at the cam and spring packages that Texas Speed and Performance offers to get a feel for cost to just do a cam.
TECH Fanatic
Joined: Sep 2008
Posts: 1,641
Likes: 526
Would a 99 have 243 heads or 241 heads? Same with intake 99 would have a LS1 intake not an LS6 intake?
I would go with a small cam. New push rods and springs. Headers. Good tune. You can still find stock 243 heads and LS6 intakes. I believe Dorman makes a LS6 repo intake. On Engine Masters they tested "econ" LS heads. I think the entry level AFR's was top dog.
I would go with a small cam. New push rods and springs. Headers. Good tune. You can still find stock 243 heads and LS6 intakes. I believe Dorman makes a LS6 repo intake. On Engine Masters they tested "econ" LS heads. I think the entry level AFR's was top dog.
Trending Topics
TECH Regular
Joined: May 2023
Posts: 417
Likes: 138
From: Franconia, PA
I found this by our buddy Eric Weingartner. He says they flow 272 at .500 I think, but at some point around .530 lift it hit 280 and then came back down. It peaked pretty early and then fell some.
243s on the other hand only flow in the 250s.
Exhaust flow is similar to 243s.
@Rich-L79 knows though that afr doesnt want you using stock rockers with these because they have bronze guides. He got 1.8 ratio rockers and then it rendered the included springs in the heads kinda useless even though his cam was smaller and his calculated lift was under the .600 lift threshold of the springs. He was getting valve float over 6k I think until he changed springs.
That kinda made me not want to mess with these heads. Plus they are over $1300 and you can get TSP ls6 brawler heads or TSP as cast 220s on sale for $1700-1750.
243s on the other hand only flow in the 250s.
Exhaust flow is similar to 243s.
@Rich-L79 knows though that afr doesnt want you using stock rockers with these because they have bronze guides. He got 1.8 ratio rockers and then it rendered the included springs in the heads kinda useless even though his cam was smaller and his calculated lift was under the .600 lift threshold of the springs. He was getting valve float over 6k I think until he changed springs.
That kinda made me not want to mess with these heads. Plus they are over $1300 and you can get TSP ls6 brawler heads or TSP as cast 220s on sale for $1700-1750.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
TECH Resident
Joined: Jun 2013
Posts: 809
Likes: 230
From: Nebraska, The Good Life
I found this by our buddy Eric Weingartner. He says they flow 272 at .500 I think, but at some point around .530 lift it hit 280 and then came back down. It peaked pretty early and then fell some.
243s on the other hand only flow in the 250s.
Exhaust flow is similar to 243s.
https://youtu.be/jQFu72DzLbk?si=3dczh6-6OFRQ74SR
@Rich-L79 knows though that afr doesnt want you using stock rockers with these because they have bronze guides. He got 1.8 ratio rockers and then it rendered the included springs in the heads kinda useless even though his cam was smaller and his calculated lift was under the .600 lift threshold of the springs. He was getting valve float over 6k I think until he changed springs.
That kinda made me not want to mess with these heads. Plus they are over $1300 and you can get TSP ls6 brawler heads or TSP as cast 220s on sale for $1700-1750.
243s on the other hand only flow in the 250s.
Exhaust flow is similar to 243s.
https://youtu.be/jQFu72DzLbk?si=3dczh6-6OFRQ74SR
@Rich-L79 knows though that afr doesnt want you using stock rockers with these because they have bronze guides. He got 1.8 ratio rockers and then it rendered the included springs in the heads kinda useless even though his cam was smaller and his calculated lift was under the .600 lift threshold of the springs. He was getting valve float over 6k I think until he changed springs.
That kinda made me not want to mess with these heads. Plus they are over $1300 and you can get TSP ls6 brawler heads or TSP as cast 220s on sale for $1700-1750.
TECH Regular
Joined: May 2023
Posts: 417
Likes: 138
From: Franconia, PA
The problem with the springs had more to do with the cam than the heads. You can buy the AFR heads with upgraded springs which is what I would have done if I'd known ahead of time that I would have needed them. AFR says you can use stock rockers but insist you have to at least do a trunion upgrade on them. Bronze guides do not like any side loading on the guides so whatever you use you need to make sure the wipe pattern on the valve stems is well centered.
Your cam was pretty low lift with non aggressive lobes. Why would that affect the springs when they were duals and good to .600 lift? I thought maybe the 1.8 rockers amplified something and pushed it over the limit, but it never really made sense to me.
interesting. I could have sworn the rocker thing was because of the guides and I don't think a trunion upgrade changes anything with respect to side loading. Maybe it does help?
Your cam was pretty low lift with non aggressive lobes. Why would that affect the springs when they were duals and good to .600 lift? I thought maybe the 1.8 rockers amplified something and pushed it over the limit, but it never really made sense to me.
Your cam was pretty low lift with non aggressive lobes. Why would that affect the springs when they were duals and good to .600 lift? I thought maybe the 1.8 rockers amplified something and pushed it over the limit, but it never really made sense to me.
TECH Regular
Joined: May 2023
Posts: 417
Likes: 138
From: Franconia, PA
Summit Racing SUM-8720-2-BHV Summit Racing Pro LS Camshaft & Spring Kits | Summit Racing
I was considering the following cam kit. The cam has .600 lift on intake and exhaust and the springs are basically PAC 1218s. 130lb seat pressure and 313lb open pressure. Think these would be sufficient with stock rockers (likely with a trunion upgrade)?
Summit Racing SUM-8720-2-BHV Summit Racing Pro LS Camshaft & Spring Kits | Summit Racing
Summit Racing SUM-8720-2-BHV Summit Racing Pro LS Camshaft & Spring Kits | Summit Racing
TECH Regular
Joined: May 2023
Posts: 417
Likes: 138
From: Franconia, PA
Valvetrain harmonics have too many variables for me to give an opinion unless the parts are just obviously mismatched. That being said, I have only seen one thread on this forum that had a specific complaint about one of Summit's cam/spring combos not being properly matched. It is a long read, but worth the time to search and read it just for the insight into how the issue was handled, if nothing else.
I guess I had a similar concern with this cam since it also has a .600 lift. I didn't want to run into similar issues or experience valve float above say 6k rpms.