LS1TECH - Camaro and Firebird Forum Discussion - Generation III Internal Engine

Help between two cams

V1_hitbox — Tue, 19 May 2026 15:22:16 GMT

Here is my simple daily driver build 2004 CTSV 4000lbs pig, 6 speed manual w/ 3:73 gear
SBE LS6, LS6 intake, 1 3/4 LT headers, 25% Under drive pulley
243�s CNC ported, milled .030 w/pac 1219�s and stock valves

I was about to order and reconfirming PTV clearance on the Cam Motion Titan 4 227/232 113+4 which was recommended by them when he said he would choose the Titan 3 224/228 113+4. He said it would help move the heavy car and pull harder under the curv. He also stated the PTV was better. I�ve been searching dyno graphs but the ls1 titan3 seems to have limited info and I was under the impression the titan4 out preformed the titan3.

More confused I reached out to a well trusted cam guru for a custom cam but he had retired and recommended the BTR Red Hot, he said PTV would clear without fly cutting. 221/24x 113. Is the exhaust PTV to close on the BTR? Funds are tight right now, so buying multiple cams is not feasible.

please, I need some help getting this completed and bolted back together.

LQ4 Van vs LQ4 Suburban/Silverado

D-n-Tyke — Sun, 17 May 2026 00:51:41 GMT

So I am diving into my 2nd LS swap project. First one I used a 2004 2500 Suburban (LQ4/4L80) as the donor. For this project I am using a 2006 3500 Van (LQ4/4L80) as the donor. What I am trying to figure out is are there any major differences between the two? I think the accessory brackets are slightly different (Van being closer to the motor). Anything else I need to worry about?

Also, since I already have the tune for the Suburban figured out (VAT removed, O2s removed, etc) can I just load the Suburban tune onto the Van ECU. Will that tune work on the Van ECU? Or do I have to rework the Van tune?

Anything else I need to know about that is different that might be a show stopper from the Van donor that I will encounter and have to rework, replace etc (ofcourse the dipstick tubes have to be swapped).

Mystery Cam - 2001 WS6

Kcole — Sat, 16 May 2026 16:40:16 GMT

Recently purchased an 2001 WS6. I was replacing the rear main seal and noticed I was not informed on the aftermarket Cam that is installed. Anyone have any idea on how to identify the Cam using the image below? Tried scanning what appears to be a QR code but no luck.

Mystery Cam

LS1 Head rebuild

jomi747 — Fri, 15 May 2026 01:29:12 GMT

Hi all. Just about to commence my head build for my cv8z Monaro (Essentially a 5.7L Pontiac GTO) and just after some advice from those who have had their heads done.
My parts list:
JHP VCM Over The Radiator Intake
Camshaft - VCM710
Crow Dual Valve Spring Kit (Seals + Retainers inc.)
Crow Super Duty 7.400" pushrods
Rollmaster Timing Chain set
ARP Balancer Bolt
ARP Cam Bolts
LS7 Lifters & Buckets
Crow cams Trunion Kit
Ramjet 1-3/4" Headers
Melling Oil Pump M10296 - High Volume

Need some input on compatibility of the listed parts, as well as a knowledgeable guide in deciding on a suitable head choice. The power goal is north of 300kw which I'd assume is possible on the 241 heads, however I've just finished my apprenticeship and got a nice bonus so I have an extra bit of cash to splash.

The two heads I've been looking at are
1. https://malexmotorsports.com/product...8424425a&_ss=r
Engine Pro Racing 243 LS1 Cathedral Port head - with a 235 CC intake runner they are bigger than the 211cc port in a 243 head and 200cc in a 241 head. They also have a 63cc combustion chamber to help bump up the comp for those naturally aspirated engines.

or

2. https://www.totalperformance.net.au/...i0jkuk-2nW9nvT
Detroit Racing Products 243 LS1 Cathedral Port heads. These have a 212 CC intake runner which is still a nice bump up from the 241 heads.

Is the extra 20 or so cc worth spending the extra $600 on? or will it not make a noticeable difference in HP/Torque numbers.

Also need some advice on what head bolts/studs are recommended to pair with the build as im overwhelmed by the variants available and would like some real world advice from those who have done the job.

Thanks in advance!

Compression check

LS1 TJ — Wed, 13 May 2026 01:17:57 GMT

So my 98 Wrangler with a LS6 swap has bit of a miss. I let it run for a bit and using my infrared temp gun the left rear header tube is about 90 degrees cooler than the other cylinders. No knocks or other bad noises. I have a scan tool and no codes detected. Engine was rebuilt about 17 years ago. New forged rods and pistons. About 20-25K miles on it.
So I replaced the coil pack on that cylinder. Had all the fuel injectors cleaned and flowed. They checked out just fine. Replaced the plug wire. Pulled the spark plug and it looked fine. Still a bit of a miss and lower temp on that cylinder.
So I'm thinking compression test on that cylinder.? Do I have to pull all of the spark plugs to get an accurate reading? Or can I just pull one of the other plugs and compare PSI wise?
How much is typical compression PSI wise? Never did a compression test on a LS engine.
Many many moons ago we were taught on carbed SBC engines you pulled all the plugs and held the throttle blade open as you crank the engine..

Need help arp studs now crank won't spin

Thillroman — Sun, 10 May 2026 22:07:33 GMT

Hi I'm putting together my first motor and I got all new bearings standard size and replaced the main studs with arp and after I tighten it down the crank won't spin my buddy says it might be becuase he lubes the crap out of the bearings before I set the crank down with sticky lube but he said to ask a form before slapping it all together and hoping the starter spins it any help would be great

LS6 cam question

JDMCRX — Thu, 07 May 2026 18:46:13 GMT

Hey guys my buddy inheritated this cam

Comp Cam

.581 intake
.612 exhaust
220 intake
244 exhaust
116 LSA 0 0

Just curious how this would do in a LS6 the exhaust duration and wide lsa makes me scratch my head !

lq9 for turbo

Eric Calhoun — Thu, 07 May 2026 10:19:04 GMT

im new to building a turbo engine but i wanna try and build one myself . i have a lq9 short block that ran great . What all do i have to buy and do to build a daily driver boost engine . Its going in a 96 impala. Just need the recip�?

LS6 Hollow & Sodium Valves With Stiffer Valve Springs

SLP IROC-Z — Mon, 04 May 2026 01:00:20 GMT

I have a pair of actual LS6 heads with the hollow & sodium valves that i want to use on my new motor but im curious if these valves are up to the task of handing stiffer valve springs. This will be a sub 7000rpm build, stock 02+ LS6 cam, Johnson 2110r lifters, Yella Terra 1.85 roller rockers and PAC 1276X springs.

PTV Clearance

Anthony_Spartan76 — Sun, 03 May 2026 02:00:47 GMT

Hey guys im new to the forum and building my first engine. I have a stock LS1 in a c5 corvette and currently doing a Cam and Heads build. Im running to an issue with i think clearance. I have in a 232/248 .621/.607 lift and 116+5 LSA cam from Cam Motion (which was recommended bu them) then I installed PRC 225cc Big Chamber Heads from Texas Speed. I chose 7.475� pushrods but I�m currently having issues with resistance when turning the engine and the driver side head installed with pushrods and rockers. When I remove the rockers it spins freely. Could it be that the pushrods are too long for the LS7 lifters or the cam is too big for the stock bottom end? Im sorry for being very misinformed, like i stated this is my very first build. Thank you so much for the advice!

6.0 lq9

Eric Calhoun — Sat, 02 May 2026 07:18:47 GMT

i have a short block 6.0 im doing the cam bearings and i have stock crank n pistons. what cam n heads should i run to get more power out of this engine with stock bottom. i want the cam real choppy..im doing a swap in a 96 impala ss and im tired of that lt1?

How screwed am I?

Richyrich78 — Fri, 01 May 2026 04:32:18 GMT

Ok, so today I pulled my stock 98 Z28 heads off and replaced them with nice ported and polished 243�s. Now here my dilema, after getting the new heads all bolted and specked on I noticed one of the steam ports had a plug in it, upon trying to get it out the little plug fell into the cooling system!!! How screwed am I if I just leave it?? Will it cause any major damage?? Please help and calm my nerves.

ati balancer issue

jonvia1234 — Wed, 29 Apr 2026 11:49:57 GMT

long story short, got a ls swapped 240sx in a trade (6.0 iron block). Had an issue with the car throwing belts. Pulled the ati pulley off, and whenever I removed the crank bolt, the pulley came right off. It was not a press fit... I sent pulley to be rebuilt and also bought a new hub for it, and same thing. Not a press fit. My question is, has anyone ran into an issue like this? I measured the crank snout and it is alot smaller compared to a stock crank. I got close to 1.4675-1.4680 with a digital caliper. Has anyone had to have a custom hub made in order to deal with the clearance issue? I realy dont want to pull the crank to replace it... looking for opinions or options. Thanks

Mixed Info About Pushrod Clearance - am I too close?

OtakuFather — Tue, 28 Apr 2026 17:05:17 GMT

Hey all -

So I have perused this forum and others online and I want to be sure, before I button this engine up and install here in the next few months that I am not making a mistake. I bought and installed thicker pushrods, but the clearance is very tight. Below are some details and images to help with opinions.

Info:

Full engine rebuild, bottom-end just back from machine shop, I put together top-end - fully upgraded rockers (better trunnions), new single springs, valve stems, valves etc.
Mild cam installed - duration @0.050 I/E 220/222 | Intake center line 110 | Lobe separation angle | Rocker ratio 1.7 | Valve lift (in.) 0.570 / 0.570

I elected to go with a sturdier pushrod, but fear I may have gone 1 step too large. Pushrods are 3/8 diameter w/0.080 wall. The motor is on a stand now, so if I have to swap out with a thinner pushrod, I have time, but want to be sure before I gear up to install the motor. Let me know thoughts, thanks in advance all!

See pics below, let me know what you think.

Basically touching

Gap on far side

Basically touching

BTR Stage 1 Cam

Pulse Red — Tue, 28 Apr 2026 10:14:10 GMT

This is for my own curiosity. I've noticed that all of a sudden quite a few 5.7 LS1 owners here in Australia are running the below BTR cam with 241 ported heads and LS6 manifolds.

217/23x .615/.636 113

Why I find that interesting is that years ago I was interested in running a sort of similar spec (more mild with much less -overlap) cam from EPS as shown below.

214/232 .605/.598 117

In the end availability to Australia stopped me considering it, but also many on USA 5.7 owners warned off running a cam like this. Reason was because it had a big split with so much exhaust duration. Not suitable for a street 5.7 with CNC 241 heads, LS6 manifold and short headers. It was a bad combination and would hurt low to mid range I was told. Stick to a small split or single pattern cams unless running Nitrous.

However, it had seemed that in the old days using something like the LPE cam below was a good thing. Very popular back then.

215/247 .629/.656 121

What's the current consensus towards cams like these for a basic 5.7 nowadays? Is a big split/ lots of exhaust duration a big no no? How about more lift on the exhaust like the BTR?