Generation III External Engine LS1 | LS6 | Bolt-Ons | Intakes | Exhaust | Ignition | Accessories
Sponsored by:
Sponsored by:

1 3/4ths or 1 7/8th headers for my setup

Thread Tools
 
Search this Thread
 
Old 03-15-2016 | 02:55 AM
  #1  
nascardude56's Avatar
Thread Starter
On The Tree
iTrader: (6)
 
Joined: Oct 2011
Posts: 178
Likes: 0
From: Orange County, CA
Default 1 3/4ths or 1 7/8th headers for my setup

I wanted to gauge if anyone has had experience with both 1 3/4ths and 1 7/8ths headers with a similar setup to mine.

Ported 241 heads
212/218 .555/.555 115 lsa cam
underdrive pulley
going to get true duals
ls6 intake

Which one would make more power? Will I sacrifice low end power withe the 1 7/8ths?
Old 03-15-2016 | 04:56 AM
  #2  
Riddle0288's Avatar
On The Tree
 
Joined: Jan 2014
Posts: 107
Likes: 0
From: Richmond, Mi
Default

(I have 1 7\8s) Buddy of mine has a bigger cam then me with ls6 intake and tune an he has 1 3\4 and from 5k+ I make almost 10 to 19+ on top end on a dyno sheet (same dyno a week a part)but I also have slp map an Ported throttle body. Not saying that's y I made more then him but that might b a good reason 2 over the headers But every car is different.
Old 03-15-2016 | 08:55 AM
  #3  
SlasherVRGR's Avatar
TECH Apprentice
iTrader: (1)
 
Joined: May 2013
Posts: 363
Likes: 1
From: NEPA
Default

It's been proven that 1 7/8 make more power even on bolt-on cars. I just picked a set of 1 7/8 SE headers for my bolt-on car. They're affordable, pretty easy to install and best of all give you more power and room to grow!
Old 03-15-2016 | 09:49 AM
  #4  
big hammer's Avatar
10 Second Club
15 Year Member
 
Joined: May 2009
Posts: 3,427
Likes: 191
From: over dere
Default

1-7/8 for all. Even 2"
Old 03-15-2016 | 11:24 AM
  #5  
nascardude56's Avatar
Thread Starter
On The Tree
iTrader: (6)
 
Joined: Oct 2011
Posts: 178
Likes: 0
From: Orange County, CA
Default

Originally Posted by SlasherVRGR
It's been proven that 1 7/8 make more power even on bolt-on cars. I just picked a set of 1 7/8 SE headers for my bolt-on car. They're affordable, pretty easy to install and best of all give you more power and room to grow!

Cool, I was thinking of getting the Speed Engineering headers too, its good to hear they are easy to install.
Old 03-15-2016 | 11:25 AM
  #6  
nascardude56's Avatar
Thread Starter
On The Tree
iTrader: (6)
 
Joined: Oct 2011
Posts: 178
Likes: 0
From: Orange County, CA
Default

I know for sure that 2" is too large for my setup, my buddy with a hci c5z picked up a lot of low end and power everywhere by stepping down to a 1 3/4.
Old 03-15-2016 | 12:22 PM
  #7  
brobinson216's Avatar
TECH Apprentice
iTrader: (11)
 
Joined: Aug 2015
Posts: 388
Likes: 1
From: Charlotte NC
Default

Originally Posted by nascardude56
I know for sure that 2" is too large for my setup, my buddy with a hci c5z picked up a lot of low end and power everywhere by stepping down to a 1 3/4.
Absolutely correct and I've experienced the same results way back in 2004 and then again in 2005.

While there are some gains in power up top, you will loose torque grunt down low on a mild setup. My real world dynojet experiences have shown 346 cube motors mimic my above statement.

Now If we are talking about max effort high compression build, the 1.875" header will shine throughout.

I always suggest 1.750" for < 12:1 N/A and even nitrous stock cube builds, and would even consider this size for 383's.

Power improvements come from collector length and design, NOT from tube size.
Old 03-15-2016 | 12:48 PM
  #8  
Chris Paveglio's Avatar
TECH Enthusiast
iTrader: (2)
 
Joined: Jan 2004
Posts: 724
Likes: 40
From: State College, PA
Default

What kind of difference do you see? I just put 1-7/8 Kooks on a stock LS1 (2001 with LS6 intake) but now I'm thinking I could have picked a better set.
Old 03-15-2016 | 04:31 PM
  #9  
nascardude56's Avatar
Thread Starter
On The Tree
iTrader: (6)
 
Joined: Oct 2011
Posts: 178
Likes: 0
From: Orange County, CA
Default

Seems like this isn't a straightforward decision haha, I've been told both opinions by reputable tuners.
Old 03-15-2016 | 04:55 PM
  #10  
brobinson216's Avatar
TECH Apprentice
iTrader: (11)
 
Joined: Aug 2015
Posts: 388
Likes: 1
From: Charlotte NC
Default

Originally Posted by Chris Paveglio
What kind of difference do you see? I just put 1-7/8 Kooks on a stock LS1 (2001 with LS6 intake) but now I'm thinking I could have picked a better set.
Kooks has/had the best collector design on the market from testing we did years ago. That title still may rein true to this day.

On a tuned bone stock 04 z06 switching from 1.875" to 1.750" both kooks with the merge spike in both. If recollection serves me best we gained ~10wt below 3100 and 6wt up 4800 and was down 2wt at 6400.

Whp was up by 5 after 3000 and gained 7whp by 6100.
Old 03-15-2016 | 05:18 PM
  #11  
Chris25's Avatar
TECH Resident
iTrader: (1)
 
Joined: Sep 2013
Posts: 774
Likes: 114
From: Clearwater, FL
Default

I just swapped out my BBK 1 3/4 for 1 7/8 and the car didn't miss a beat. I wouldn't waste my time putting 1 3/4 on there you will regret it down the road when you want just a little more.
Old 03-15-2016 | 05:25 PM
  #12  
nascardude56's Avatar
Thread Starter
On The Tree
iTrader: (6)
 
Joined: Oct 2011
Posts: 178
Likes: 0
From: Orange County, CA
Default

Originally Posted by Chris25
I just swapped out my BBK 1 3/4 for 1 7/8 and the car didn't miss a beat. I wouldn't waste my time putting 1 3/4 on there you will regret it down the road when you want just a little more.
Do you have any dyno numbers?
Old 03-15-2016 | 06:30 PM
  #13  
Chris25's Avatar
TECH Resident
iTrader: (1)
 
Joined: Sep 2013
Posts: 774
Likes: 114
From: Clearwater, FL
Default

Originally Posted by nascardude56
Do you have any dyno numbers?
Unfortunately not yet just put the cam in and I'm in the process of getting my fast 90 ported so after that and a tune I will get it to the dyno.
Old 03-15-2016 | 07:48 PM
  #14  
Chris Paveglio's Avatar
TECH Enthusiast
iTrader: (2)
 
Joined: Jan 2004
Posts: 724
Likes: 40
From: State College, PA
Default

I plan on a dyno day and tune in about a month so I will see how it goes. I also have my dyno sheet from when I first got the car, so hopefully it will compare well. I'll post pix.
I also had heard both things - "get 1.75" and "any header will give you gains over stock". My car is likely not going to see heads/cams because for SCCA I want to stay in my class.
Old 03-15-2016 | 07:55 PM
  #15  
Chris25's Avatar
TECH Resident
iTrader: (1)
 
Joined: Sep 2013
Posts: 774
Likes: 114
From: Clearwater, FL
Default

Honestly for the price you cant go wrong with the 1 7/8 headers from TSP or SE.
Old 03-15-2016 | 08:14 PM
  #16  
Rise of the Phoenix's Avatar
TECH Senior Member
iTrader: (27)
 
Joined: Dec 2009
Posts: 9,728
Likes: 10
From: Jefferson City, MO
Default

I too agree 1 7/8" is the way to go. This is coming from a guy who has 1 3/4" headers.
Old 03-15-2016 | 08:26 PM
  #17  
ragtopz28's Avatar
TECH Addict
iTrader: (57)
 
Joined: Aug 2007
Posts: 2,014
Likes: 11
From: Ft. Myers, FL
Default

I went with the SE 1 7/8" for my "nitrous needs" and she rips up top. I will say I think she suffered a little bit down low (on motor). No intentions of starting an argument or rehashing the old, just my experience.
The SE headers are the easiest header install I have ever done and the price point is unreal (SS headers and Y-pipe to my door for under $400 ).
Old 03-15-2016 | 08:53 PM
  #18  
big hammer's Avatar
10 Second Club
15 Year Member
 
Joined: May 2009
Posts: 3,427
Likes: 191
From: over dere
Default

Originally Posted by nascardude56
I know for sure that 2" is too large for my setup, my buddy with a hci c5z picked up a lot of low end and power everywhere by stepping down to a 1 3/4.
Not really. 2" headers are even worth a few hp over 1-7/8 on a stock ls3. Who cares about a few ft\lbs of torque between idle and 1500 rpm.
Old 03-15-2016 | 09:06 PM
  #19  
redbird555's Avatar
TECH Veteran

iTrader: (14)
 
Joined: Mar 2009
Posts: 4,444
Likes: 9
From: Pompano Beach FL
Default

Originally Posted by nascardude56
I know for sure that 2" is too large for my setup, my buddy with a hci c5z picked up a lot of low end and power everywhere by stepping down to a 1 3/4.
He likely didnt at all 1-7/8 lose nothing down low on every dyno posted and from my own experience but gain power up top.
Originally Posted by brobinson216
Absolutely correct and I've experienced the same results way back in 2004 and then again in 2005.

While there are some gains in power up top, you will loose torque grunt down low on a mild setup. My real world dynojet experiences have shown 346 cube motors mimic my above statement.

Now If we are talking about max effort high compression build, the 1.875" header will shine throughout.

I always suggest 1.750" for < 12:1 N/A and even nitrous stock cube builds, and would even consider this size for 383's.

Power improvements come from collector length and design, NOT from tube size.
Do you have some dyno sheets to compare that too? There isnt one dyno on here that shows any loss of tq on an ls motor with larger headers. I have made the switch several times, each time 1-7/8 loses nothing down low and pulls away over 4500.

Op go 1-7/8 or get stepped headers if you can as they will bet better still. But they are very expensive so on a budget go 1-7/8
Old 03-15-2016 | 09:49 PM
  #20  
nascardude56's Avatar
Thread Starter
On The Tree
iTrader: (6)
 
Joined: Oct 2011
Posts: 178
Likes: 0
From: Orange County, CA
Default

Originally Posted by ragtopz28
I went with the SE 1 7/8" for my "nitrous needs" and she rips up top. I will say I think she suffered a little bit down low (on motor). No intentions of starting an argument or rehashing the old, just my experience.
The SE headers are the easiest header install I have ever done and the price point is unreal (SS headers and Y-pipe to my door for under $400 ).
Kind of off topic, but did the Y-pipe go in ok? These are the headers I am thinking of getting.


Quick Reply: 1 3/4ths or 1 7/8th headers for my setup



All times are GMT -5. The time now is 01:13 PM.