1 3/4 vs 1 7/8 Headers Upgrade - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

naws · 02-24-2018, 03:38 PM

I currently have an LS3 with 1 3/4 headers and I'm going to be pulling it out to build the engine. 416 stroker and built for a small amount of boost as well with ultimate goals around 700rwhp. However, I'll be keeping it NA for a year or so before I add boost so I'd like to be close to 500rwhp then.

Since my car currently has 1 3/4" headers is it worth upgrading to 1 7/8" or would the gain be so little that it just isn't worth it. Yes I realize it would help even more with the boost in a year and a bit but hitting those numbers with a stroker and boost shouldn't be hard anyways.. Curious on opinions though as if I'm going to i may as well do it when the engine is out.

Thanks

WHAMMO · 02-24-2018, 04:29 PM

upgrade to 2'', worth it on a 416, hell it is on a boltons 376 LS3. You wont be asking yourself after if you should have gone bigger. Cant find the thread, there was a 2'' vs 1 7/8 and the 2'' was better. the difference was minimal though, I'd guess its even better on a cammed 416ci with ported heads. Plus there is some cheap 2'' LTs. I have the Stainless Works. Fit perfect,(some very light hammering on the heat shield), I am very satisfied, did the install myself.

You will find that most shop, (very good LS shop!), will still recommend 1 7/8 or stepped headers and they think its a better setup for a LS3, for fitment and hp under 6-700. Some other guys say 2''. Janetty did a legit test and the 2'' did better everywhere. Unless another shop is doing a new test, showing otherwise, I leaning towards 2'', for a LS3 5th gen Camaro.

-Heres some good reading on both sides http://www.camaro5.com/forums/showth...=174982&page=3

Honestly if i had a Vette, I would consider 1 7/8, even LG 1 3/4 because the Vette is limited in space VS the Camaro design.

And if you really wanna get confused watch this haha...they dented primaries pretty badly to see if it hurts the hp on the dyno, it doesn!! ..OMG!

Heres the thread;
http://www.camaro5.com/forums/showthread.php?t=63640

Our Test Car is none other than, Bigdogs LS3 Camaro used in our CAI test.
This Car is 100% Stock other than the Headers installed for the Testing.

Stock Peak Numbers 373 RWHP 378 RWTQ
Stock Average Numbers I will post tomorow Forgot to print them.

1.75 long tube headers w high flow cats Peak 401.1 HP 403.8 TQ
1.75 long tube headers w high flow cats Average 281.2 HP 363.9 TQ

1.875 long tube headers w high flow cats Peak 406.8 HP 407.5 TQ
1.875 long tube headers w high flow cats Average 283.7 HP 366.6 TQ

2.0 long tube headers w high flow cats Peak 411.7 HP 408.9 TQ
2.0 long tube headers w high flow cats Average 288.1 HP 368.1 TQ

The 1 3/4 Headers did Surprisingly well.
The 1 7/8 Headers IMO are the best all around header.
The 2.0 Headers are neck and neck with the 1 7/8 but Slightly stronger from 5000 to 6300

naws · 02-24-2018, 05:03 PM

Nice chart comparison. It's in a 1969 Camaro so I'm not sure if they make a 2" primary header. Will have to look into that

naws · 03-04-2018, 10:48 PM

No other comments? Trying to decide if that 1/8" increase will be worth it..

Pro-tuned · 03-05-2018, 03:05 AM

I wouldn’t go beyond 1 7/8 for up to 700WHP as it’s not worth the return on HP under 5500RPM. Some spacers may be required depending on mfg, cats and exhaust.

I just completed a 2 X 3 full system but that’s relative to my setup. Headers and Cats fit without modifications (other than wide band). I installed it in a vert which mfg said don’t fit. I just had to make all braces and minor adjustment to rear housing.

You can check the build;
http://www.camaro5.com/forums/showthread.php?t=522306

Good luck in your informed decision!

xc_SS/RS · 03-05-2018, 08:15 AM

go as large as you are comfortable with. you'll have plenty of torque so i wouldn't be too worried about running the larger headers. i would imagine its just a matter of if they fit in the car

GONIF · 03-05-2018, 11:21 AM

416 , go 2 inch

eLeSthree · 03-05-2018, 11:49 AM

I went straight to 2inch header from stock. Zero negatives on the NA setup, and now they are ideal for the supercharger going in.

But, that being said, my buddy runs a 1 7/8 and you would never know the difference if you drove both cars.

TSP's price on the 2inch was the same as the 1 7/8, so why not?

02-24-2018, 03:38 PM	#1
naws Drives: 1969 Camaro SS Join Date: Feb 2018 Location: Vancouver Posts: 15	1 3/4 vs 1 7/8 Headers Upgrade I currently have an LS3 with 1 3/4 headers and I'm going to be pulling it out to build the engine. 416 stroker and built for a small amount of boost as well with ultimate goals around 700rwhp. However, I'll be keeping it NA for a year or so before I add boost so I'd like to be close to 500rwhp then. Since my car currently has 1 3/4" headers is it worth upgrading to 1 7/8" or would the gain be so little that it just isn't worth it. Yes I realize it would help even more with the boost in a year and a bit but hitting those numbers with a stroker and boost shouldn't be hard anyways.. Curious on opinions though as if I'm going to i may as well do it when the engine is out. Thanks

03-05-2018, 03:05 AM	#5
Pro-tuned Angewendet Ingenieur Drives: 14 Camaro ZL1 Join Date: Apr 2015 Location: USA Posts: 401	I wouldn’t go beyond 1 7/8 for up to 700WHP as it’s not worth the return on HP under 5500RPM. Some spacers may be required depending on mfg, cats and exhaust. I just completed a 2 X 3 full system but that’s relative to my setup. Headers and Cats fit without modifications (other than wide band). I installed it in a vert which mfg said don’t fit. I just had to make all braces and minor adjustment to rear housing. You can check the build; http://www.camaro5.com/forums/showthread.php?t=522306 Good luck in your informed decision! __________________ ———— LQ9, Iron Block, Forged internals, 408CI, Jannetty custom cam, TS short block, Whipple, Hardened Jackshaft, PRC 260, 2X3 Dynatech Full Competition, HF Cats, CAI, NW 103, Chee, ID 1300, COPO Breather, MSD, Fore Dual Pump, ultratorque, E85, dual Meth, True Trac, 3:45, 1500hp axle-shafts, DSS CF, BMR, custom Pearl/Candy paint by Jaidah. Last edited by Pro-tuned; 03-05-2018 at 03:21 AM.

03-05-2018, 08:15 AM	#6
xc_SS/RS Drives: 2010 Camaro SS/RS Join Date: Mar 2014 Location: somewhere in MD Posts: 4,883	go as large as you are comfortable with. you'll have plenty of torque so i wouldn't be too worried about running the larger headers. i would imagine its just a matter of if they fit in the car __________________ 2010 2SS/RS Z/28 intake, NW, FAST 102, speed engineering LT's, some exhaust, ATI -10% pulley, GM flex fuel injectors, DSX flex fuel sensor, MGW shifter, HP Tuners, some suspension work, stickers and a little weight loss. 12.63 @113.53

03-05-2018, 11:21 AM	#7
GONIF Drives: 73 VETTE ,, 05 2500hd diesel,14 1LE Join Date: Feb 2014 Location: The Left lane PHOENIX AZ Posts: 2,626	416 , go 2 inch __________________ OLD GUY FLYING FAST AND LOW

03-05-2018, 11:49 AM	#8
eLeSthree Drives: 2011 Camaro SS 6sp Join Date: Nov 2016 Location: Drivers Seat Posts: 1,904	I went straight to 2inch header from stock. Zero negatives on the NA setup, and now they are ideal for the supercharger going in. But, that being said, my buddy runs a 1 7/8 and you would never know the difference if you drove both cars. TSP's price on the 2inch was the same as the 1 7/8, so why not? __________________ 2011 Camaro SS---SOLD TMS Dart 427 FED M311s, ESS Tuning G4 Blower, DSX Triple FP Assembly, DSX FF, FIC1300, Mcleod RXT 1200HD, Edlebrock Pro Flo XT 1158whp 1017wtq. 2010 CTS-V A6 - "Stock" SOLD 630whp 658wtq 2024 F-150 RCSB 5.0 4x4 waiting for tunes...

02-24-2018, 05:03 PM	#3
naws Drives: 1969 Camaro SS Join Date: Feb 2018 Location: Vancouver Posts: 15	Nice chart comparison. It's in a 1969 Camaro so I'm not sure if they make a 2" primary header. Will have to look into that

03-04-2018, 10:48 PM	#4
naws Drives: 1969 Camaro SS Join Date: Feb 2018 Location: Vancouver Posts: 15	No other comments? Trying to decide if that 1/8" increase will be worth it..