Building 6.0 N/A First Time
Thread Starter
Teching In
Joined: Mar 2024
Posts: 3
Likes: 0
From: Ohio
Building 6.0 N/A First Time Hey y’all new to the LS world mostly been an import guy but recently sold all that and moved on to the V8 world. I picked up a couple of Gen 3 LQ4 blocks and I’m looking to build a N/A high compression build something simple and modest. HP goals of around 450-550. I am finding a lot of information on cylinder heads but was wondering in y’all’s opinions what’s the best choice for a N/A 6.0 build for that power and range. I currently have a couple good sets of 317 Cathedral port heads but read those are better for boost and I should look at LS3 heads 823 or the 243. Appreciate all the information. Thank you.
It's been said that cathedral heads provide more torque down low than rectangular port heads. The rectangular heads L92 (823) or LS3 (821) are essentially the same head with the only difference being that the 821's come with hollow stem intake valves and a better set of valve springs with both having 2.165 int and 1.59 exh valves. The rectangular heads do generally make more horsepower than cathedral port heads but only when referring to non ported stock castings. There's different castings of cathedral port heads ranging from the small bore 862 and 706 (Basically the same head) which have smaller valves (1.89 Int and 1.55 exh) up to the 241, 243/799 and 317's which all came with 2.00 intake and 1.55 exhaust valves. There's no arguing that rectangular port heads make more horsepower which was the deciding factor for me.
Thread Starter
Teching In
Joined: Mar 2024
Posts: 3
Likes: 0
From: Ohio
Thread Starter
Teching In
Joined: Mar 2024
Posts: 3
Likes: 0
From: Ohio
It's been said that cathedral heads provide more torque down low than rectangular port heads. The rectangular heads L92 (823) or LS3 (821) are essentially the same head with the only difference being that the 821's come with hollow stem intake valves and a better set of valve springs with both having 2.165 int and 1.59 exh valves. The rectangular heads do generally make more horsepower than cathedral port heads but only when referring to non ported stock castings. There's different castings of cathedral port heads ranging from the small bore 862 and 706 (Basically the same head) which have smaller valves (1.89 Int and 1.55 exh) up to the 241, 243/799 and 317's which all came with 2.00 intake and 1.55 exhaust valves. There's no arguing that rectangular port heads make more horsepower which was the deciding factor for me.
Trending Topics
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 Senior Member
Joined: Jun 2016
Posts: 22,291
Likes: 3,616
From: Central Cal.
What got my attention was the nearly identical reply to well over half a dozen threads on this forum alone.
His vehicle is an 09 Prius.... Why he mentioned it here is curious....
I post a lot, but not to me being repetitious and within minutes of each other.
None taken, my friend, and your comment is well founded.
What got my attention was the nearly identical reply to well over half a dozen threads on this forum alone.
His vehicle is an 09 Prius.... Why he mentioned it here is curious....
I post a lot, but not to me being repetitious and within minutes of each other.
What got my attention was the nearly identical reply to well over half a dozen threads on this forum alone.
His vehicle is an 09 Prius.... Why he mentioned it here is curious....
I post a lot, but not to me being repetitious and within minutes of each other.
TECH Senior Member
Joined: Jun 2016
Posts: 22,291
Likes: 3,616
From: Central Cal.
I PM’d him yesterday some info for a guy local to me that deals in LS pullouts. He only sells quality, running units with a warranty. GarageBeers tried to PM me back and it wouldn’t let him due to low post count, so I imagine this is why all the 4-5 word posts by him today…to build post count. Yup Gary, you walked right into that one indeed. 😜
TECH Senior Member
Joined: Jun 2016
Posts: 22,291
Likes: 3,616
From: Central Cal.
Yup. Shore did, but it's all good, especially if you're able to help him out here and there with your usual good advice.
Until I saw his thread, I almost thought he was a troll. I'm glad that's not the case.
He'll get lots of help here.
Until I saw his thread, I almost thought he was a troll. I'm glad that's not the case.
He'll get lots of help here.
10 Second Club
Joined: Aug 2010
Posts: 4,465
Likes: 192
From: Harford Co. Maryland
I bought my LS3 heads straight from SDPC with the spring upgrade...figured by the time I bought heads (hoping they were good), had a machine shop go over them, add the .660 springs, I'd be close to the same price (got them cheap IMO)
Just another option.
Just another option.
Last edited by Doug G; Mar 19, 2024 at 05:42 PM.
12 Second Club
Joined: Dec 2017
Posts: 1,033
Likes: 221
From: San Antonio
The LQ4 gives you almost too many options. For a budget build, I would mill the 317 heads about.030”, swap to flat top pistons, and use a Summit cam in the 228/232 range Oh, and stock TBSS intake, if you can find one. If not, the stock truck intake is fine. This combo should make over 500hp at the crank.
If you want to go wild, get TFS 220 heads, FAST-102 intake, flat top pistons, and bigger cam (comp 54-459-11). That combo should make over 550hp at the crank.
If you want to go wild, get TFS 220 heads, FAST-102 intake, flat top pistons, and bigger cam (comp 54-459-11). That combo should make over 550hp at the crank.
11 Second Club
Joined: Jan 2003
Posts: 1,000
Likes: 134
TECH Veteran
Joined: Sep 2014
Posts: 4,893
Likes: 703
From: Mississippi
No need to spend money on aftermarket heads for 550 horse motor. Richard H... built a 5.3 with Katech cnc 706 castings with a summit racing cam. Cheap cnc program and cheaper than camshaft. Motor made 508 horses at the crank.