Which header for LS2
Thread Starter
Safety Car
Joined: Apr 2017
Posts: 3,708
Likes: 344
From: Texas By God
Which header for LS2
I have a 05 Z51 6 speed LS2 street cruiser weekend toy. I had a BTR stage two cam kit installed B&B axle back and now am ready for headers. The cam definitely improved performance and has a sexy lope too.
However to me and my seat of the pants dyno it seem the cam cost me some low end torque below 3500.
I plan to get Kook ceramic coated headers but not sure which size. Currently have a mild tune at 388 RWT and 406 HP on mustang dyno.
I want as much torque down low as I can get. Make me a suggestion please.
However to me and my seat of the pants dyno it seem the cam cost me some low end torque below 3500.
I plan to get Kook ceramic coated headers but not sure which size. Currently have a mild tune at 388 RWT and 406 HP on mustang dyno.
I want as much torque down low as I can get. Make me a suggestion please.
Last edited by Texan79423; Mar 31, 2018 at 07:57 AM.
Safety Car
Joined: May 2011
Posts: 3,807
Likes: 508
From: Oshawa, Ontario
I have a 05 Z51 6 speed LS2 street cruiser weekend toy. I had a BTR stage two cam kit installed B&B axle back and now am ready for headers. The cam definitely improved performance and has a sexy lope too.
However to me and my seat of the pants dyno it seem the cam cost me some low end torque below 3500.
I plan to get Kook ceramic coated headers but not sure which size. Currently have a mild tune at 388 RWT and 406 HP on mustang dyno.
I want as much torque down low as I can get. Make me a suggestion please.
However to me and my seat of the pants dyno it seem the cam cost me some low end torque below 3500.
I plan to get Kook ceramic coated headers but not sure which size. Currently have a mild tune at 388 RWT and 406 HP on mustang dyno.
I want as much torque down low as I can get. Make me a suggestion please.
exhaust manifold gaskets and with the money you save you will be able to buy a new ported Fast 102 intake manifold
Le Mans Master
Joined: Oct 2014
Posts: 8,672
Likes: 2,726
From: Atlanta GA
If you are staying NA and its low end torque you are looking for go with 1 7/8 or 1 3/4 tubes . I would stay away from the cheap brands as they use mild steel or cheap stainless, may threads about fit also . Can't go wrong with Kooks or LG. I went with LG and the fit was fantastic ,easy to install , they tucked up in the tunnel nicely and plenty of clearance around the plugs
Dave
Dave
Melting Slicks
Joined: Jun 2006
Posts: 2,483
Likes: 261
From: Miami Florida
Kooks are a great choice cause they go rite in without dropping the cradle or removing the starter like with the ARH as for size 1 7/8 for sure.
Definitely get a 3 inch Kooks X pipe as well even if you keep your 2 1/2 oem axle back it will make a big difference however 3 inch all the way across is best.
Reason you feel like you lost some power down low is exhaust restriction that will go away with the headers and will pick up your top end too.
Definitely get a 3 inch Kooks X pipe as well even if you keep your 2 1/2 oem axle back it will make a big difference however 3 inch all the way across is best.
Reason you feel like you lost some power down low is exhaust restriction that will go away with the headers and will pick up your top end too.
Drifting
Joined: Dec 2016
Posts: 1,373
Likes: 217
It was a little ugly on the head flanges but overall a great cost/performance piece. I'd do it again and I am fairly critical of things I put on the car. O2 clearances were fine and I got everything in with no issues. it hangs a little low but not as bad as some of the other headers ive seen pics of.
Melting Slicks
Joined: Jun 2006
Posts: 2,483
Likes: 261
From: Miami Florida
after i tried to go american and they left me hanging (waited over 6 weeks with no shipment), I gave up and I picked up a set of OBX. Got it in 3 days!
It was a little ugly on the head flanges but overall a great cost/performance piece. I'd do it again and I am fairly critical of things I put on the car. O2 clearances were fine and I got everything in with no issues. it hangs a little low but not as bad as some of the other headers ive seen pics of.
It was a little ugly on the head flanges but overall a great cost/performance piece. I'd do it again and I am fairly critical of things I put on the car. O2 clearances were fine and I got everything in with no issues. it hangs a little low but not as bad as some of the other headers ive seen pics of.
I like to make the car easy to work on.
Drifting
Joined: Dec 2016
Posts: 1,373
Likes: 217
I bought the ARH and both leaked from all four fixed it myself but installing and removing them is a pita sold them and got kooks these too hang a little low but installation and removal is a piece of cake if you let em go will drop all the way to the floor.
I like to make the car easy to work on.
I like to make the car easy to work on.
Yup, never really heard much bad things about kooks.If money was no object I'd def go jet-hot coated kooks. with my current situation, i needed to go budget
. dont regret it at all though - and normally being penny wise pound foolish makes me 
.
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Pro
Joined: Oct 2016
Posts: 613
Likes: 103
From: Farmington Arkansas
If you are staying NA and its low end torque you are looking for go with 1 7/8 or 1 3/4 tubes . I would stay away from the cheap brands as they use mild steel or cheap stainless, may threads about fit also . Can't go wrong with Kooks or LG. I went with LG and the fit was fantastic ,easy to install , they tucked up in the tunnel nicely and plenty of clearance around the plugs
Dave
Dave
I went with LG also. Sound great, fit great. High quality product.
Le Mans Master
Joined: Jan 2008
Posts: 6,457
Likes: 297
From: corpus christi Texas
I bought the ARH and both leaked from all four fixed it myself but installing and removing them is a pita sold them and got kooks these too hang a little low but installation and removal is a piece of cake if you let em go will drop all the way to the floor.
I like to make the car easy to work on.
I like to make the car easy to work on.
Drifting
Joined: Dec 2016
Posts: 1,373
Likes: 217
If its not MLS you should redo it yourself. Its not that difficult to remove/replace just the gasket. Start from the middle outwards. finger tight, from middle->out, then 11 ft lbs, then 15 ft lbs.
so that would be a pattern like 3,4,2,5,1,6 (doesnt matter which side you count from.)
You should really fix that leak - the only "tight" seal thats really necessary is the flange since O2s are reading post flange. Everything past the primary O2s dont need to be truly "leak free" - it will sound better and you'll get a bit more power but your car will be running fine.
Le Mans Master
Joined: Jan 2008
Posts: 6,457
Likes: 297
From: corpus christi Texas
Wow, that sucks. Do you know if its MLS or paper gaskets?
If its not MLS you should redo it yourself. Its not that difficult to remove/replace just the gasket. Start from the middle outwards. finger tight, from middle->out, then 11 ft lbs, then 15 ft lbs.
so that would be a pattern like 3,4,2,5,1,6 (doesnt matter which side you count from.)
You should really fix that leak - the only "tight" seal thats really necessary is the flange since O2s are reading post flange. Everything past the primary O2s dont need to be truly "leak free" - it will sound better and you'll get a bit more power but your car will be running fine.
If its not MLS you should redo it yourself. Its not that difficult to remove/replace just the gasket. Start from the middle outwards. finger tight, from middle->out, then 11 ft lbs, then 15 ft lbs.
so that would be a pattern like 3,4,2,5,1,6 (doesnt matter which side you count from.)
You should really fix that leak - the only "tight" seal thats really necessary is the flange since O2s are reading post flange. Everything past the primary O2s dont need to be truly "leak free" - it will sound better and you'll get a bit more power but your car will be running fine.
..NOTE: One photo below #15
Last edited by Cherokee Nation; Apr 4, 2018 at 11:43 PM. Reason: add
Drifting
Joined: Dec 2016
Posts: 1,373
Likes: 217
Ohh. They probably did too much inner porting after they welded the tube. If its a really thin break in the weld the carbon might seal up the holes enough so they arent leaking anymore. Or, if they only leak at WOT it might not matter since the car goes into open loop anyway and ignores the O2s.
That is prtty terrible that ARH won't honor it though. I can understand a defect since i believe the porting is done by hand after its welded, but they should stand by their products.
That is prtty terrible that ARH won't honor it though. I can understand a defect since i believe the porting is done by hand after its welded, but they should stand by their products.
Le Mans Master
Joined: Jan 2008
Posts: 6,457
Likes: 297
From: corpus christi Texas
Ohh. They probably did too much inner porting after they welded the tube. If its a really thin break in the weld the carbon might seal up the holes enough so they arent leaking anymore. Or, if they only leak at WOT it might not matter since the car goes into open loop anyway and ignores the O2s.
That is prtty terrible that ARH won't honor it though. I can understand a defect since i believe the porting is done by hand after its welded, but they should stand by their products.
That is prtty terrible that ARH won't honor it though. I can understand a defect since i believe the porting is done by hand after its welded, but they should stand by their products.
Drifting
Joined: Dec 2016
Posts: 1,373
Likes: 217
They say lifetime warranty,but that is BS...I went back and forth with them and the shop and they keep saying that they are making a new set for me and that was two years ago...I gave up and filed a suit against them...Question: Do you mean the primary 02s? because that is the only two that is on my vette the other two was deleted.
Yup, the primary O2s are the important ones. The 2ndary is only there to check catalytic convertor performance. However, in open loop (WOT), fueling is not affected by O2 readings.
