gta3uzi

Are they amazing? Or should I go with 1 7/8ths?

How difficult are the set from Kooks to install? (If anyone knows, that is...)

Avaric3

iTrader: (3)

wuts your engine setup look like? if you have stock cubes youre not gonna really need 2" primaries

99SSJarhead

iTrader: (2)

Yeah, unless you are fixing to drop several grand into your engine and bump it up into the 500+ HP range really quick, 2" primaries aren't really going to do much. They will flow nicely, but more than likely your intake and heads will become a limiting factor and you won't see the full amount of gains you could with 2".

At stock to lightly modified, a set of 1 3/4 tends to be all you need. If you know you are gonna be pushing over time for around 450, then 1 7/8 would be good.

gta3uzi

Has anyone done a dyno test on a stock cube motor between 1 7/8ths and 2"?

The only reason I'm wondering is because many said there would be no gain between 1 3/4 and 1 7/8 on stock cubes and that you would lose low-end torque, but we have found these claims to be unsubstantiated.

There's also the issue of spark plugs and installation. Oh, so many questions! But if I'm spending $1500 on headers and a Y, I'm intent on getting all of the answers

Beaflag VonRathburg

iTrader: (176)

I bought a set of 2'' headers a while ago from the classifieds for $600 shipped. I am in the process of installing an L92 short block with TFS 225 heads, a ported FAST 90mm intake, 100mm TB, and a solid roller cam. I was originally looking for a 1-7/8ths header, but stumbled upon the 2''s. I did some research and based buying them on:
http://www.camaro5.com/forums/showthread.php?t=63640
Keep in mind that is on an oem LS3 engine, but the results kind of suprised me.

Engine_HP

iTrader: (1)

nice thread, thanks for sharing.

RS_SS69

iTrader: (31)

Ive installed 2 sets of Kooks 2" headers and they are in everyway amazing. Plug access is easy, fitment couldnt be better, there is clearence everywhere. Best fitting header I have installed. If you figure most 1 and 7/8 headers that are good cost around the 7-900 range, Kooks 2" are right there so why not spend the extra cash. You can also get y pipes that can be either to a stock catback, 3", 3.5" or 4". Those fit really well also. If your already spending the money get the 2"

dgcustomz

iTrader: (127)

Here is the reason on why to use the 1-7/8's over the 2". This is from the link that was provided above..

A few Reasons, the additional cost does not justify the gains.
They are a Tighter fit.
They are Heavier
Most manufacturers offer a 1 7/8 headers so they are easier to get.
The biggest gains from headers are in the middle of the curve where you drive most and you can't tell the difference between 1 7/8 and 2 inch, on the dyno graph or in the car.

Unless your Racing you won't miss the 5 HP at 6300 RPM, your not there enough to use it on the street.

I have Kooks 1-7/8 headers and I love them. Great fitment and good floor clearance.
I also have some for sale if interested.

turbo

iTrader: (10)

Heavier? this point is mute because the same argument can be said for going from 1 3/4 to 1 7/8..

5 HP is 5 HP....People spend stupid money to gain 5 HP. Take for example an underdrive pulley or swap out an h-pipe for an x-pipe or even a new style air lid...list goes on.

If you can get 2" headers for nearly the same cost or within couple hundred dollars? why not? Significant difference in price....probably not.

gta3uzi

I do plan on replacing the rod bolts (yay stretch gauges) and springs so I may safely increase the red line and shift points to 6500rpm.

The difference between either 1 3/4" or 1 7/8" and 2" is one Ulysses S. Grant. $10/hp is a pretty good price.

The only things I would be worried about at this point would be the fit. I'll be putting on solid motor mounts at the same time, so hopefully there won't be any clearance issues.

I was considering another manufacturer, but after reading about their horrible customer service I've decided to go with the more expensive stainless manufacturer. Any word on Kook's CS department?

RS_SS69

iTrader: (31)

Ive never had an issue with getting ahold of Kooks CS.

As for weight on the 2" could not believe they were that light, I felt like I was gonna break the damn things, compared to a set of american racing 1 7/8s I just installed they were at least half the weight and fit 20x better.

Beaflag VonRathburg

iTrader: (176)

^ The first time I picked them up I was suprised at how light my 2'' kooks were. They're way lighter than stock manifolds.