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Kook's Header & Exhaust - Gain 35HP; 40TQ

Just completed the install of an entire Kook's exhaust system - from the long tube headers, Boss 302 specific H-pipe, and mufflers. Took this LS and an identical LS with a stock exhaust system and put them both on the dyno back to back. Here are the results from the Kook's. Very, very impressive that there is a very consistent gain across the ENTIRE rpm range. A very worthwhile modification in our opinion.

I'd post the graph if an admin tells/allows me to.
 
Kendall, go ahead and post the graph buy you'll need to use an external hosting site or use the link for the image from the other site. ;)

Is the system with the CATS smog legal in CA? And what if any difference in HP do you expect from the H vs. X mid pipe? Is the difference mostly the sound?
 
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nota4re said:
Just completed the install of an entire Kook's exhaust system - from the long tube headers, Boss 302 specific H-pipe, and mufflers. Took this LS and an identical LS with a stock exhaust system and put them both on the dyno back to back. Here are the results from the Kook's. Very, very impressive that there is a very consistent gain across the ENTIRE rpm range. A very worthwhile modification in our opinion.

I'd post the graph if an admin tells/allows me to.

- Are you running the Kook's setup with the track key?
My dealer made a big deal that any modifications after the track key implementation would void warranty...

(I'd like to see the dyno chart.)
Thanks!
 
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5 DOT 0 said:
Here's the chart.

188-cool-tech-kooks-vs-stock-dyno-results-lswkooks.jpg

...On the other hand and since I am not interested in forced induction, Hennessy has a stage 1 kit here:

http://www.hennesseyperformance.com/hpe490-boss-302.html

It seems the Kooks kit with a good aftermarket air box might be a (much) better buy.
But my concern is for the tune, and especially the track key.
Does anyone have experience with getting an aftermarket tune & warranty situation?
It seems to me that the Hennessy tune would wipe out the track key flash.
Has anyone dealt with this scenario?
Thanks.
 
It seems the Kooks kit with a good aftermarket air box might be a (much) better buy.
But my concern is for the tune, and especially the track key.
Does anyone have experience with getting an aftermarket tune & warranty situation?
It seems to me that the Hennessy tune would wipe out the track key flash.
Has anyone dealt with this scenario?
Thanks.

We did dyno pulls with and without the track key. Note that all of our track key pulls were with the car started, warmed and in "Track Key Engine Enabled Mode". We did the pulls first with the stock-exhaust LS (mine) so that we could capture very precise A/F values across the RPM range. We repeated the same careful procedure with the Black Key - noting precise A/F trends. The reason that we were so careful in testing the stock car first was that we knew we would *try* doing the header-equipped car with no tuning modifications - and traditionally, this might result in a lean condition. As such, we were ready to abandon the pull if we didn't like the A/F's. We were VERY PLEASANTLY SURPRISED that the wide-band equipped Boss ECU more than adjusted for the Headers!!! A/F's were pretty equivalent if not slightly richer than the OEM car in BOTH Track Key and Black Key modes. I will post some detailed A/F graphs a little later - we're using the daylight to get the same header set-up on my car - albeit this time with the CATs. Our conclusion is that you DO NOT need a tune for the headers as the A/F's are right on the money - and the HP/TQ is really there as indicated in the chart. Again, I hope the forum members can appreciate how significant this is. We're NOT talking about a peak HP/TQ benefit , yet a benefit across the ENTIRE RPM range!
 
Is the system with the CATS smog legal in CA? And what if any difference in HP do you expect from the H vs. X mid pipe? Is the difference mostly the sound?

A few points to make here. First, you don't have to smog a car in California for the first 6 years of ownership. Second, it is VERY EASY with the Kook's system to swap the CAT in and out. Third, yes, I believe the new (just released) "green" CAT from Kook's will pass California emissions. Last point, in a complete catastrophe, it would be an easy job to adapt the OEM cats to work with the Kook's system - and we might offer this as a service.... in 2019.

H-Pipe vs X-Pipe would admittedly be interesting but I wouldn't expect a performance difference to be measureable either way. We opted for the unique Boss 302 H-pipe so that we could retain the side pipes and the owner can tailor the sound with different discs. The most weight conscious owners (it IS that time of year - lol) can even choose to cap the side exhausts and remove them from the car.
 
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nota4re said:
It seems the Kooks kit with a good aftermarket air box might be a (much) better buy.
But my concern is for the tune, and especially the track key.
Does anyone have experience with getting an aftermarket tune & warranty situation?
It seems to me that the Hennessy tune would wipe out the track key flash.
Has anyone dealt with this scenario?
Thanks.

We did dyno pulls with and without the track key. Note that all of our track key pulls were with the car started, warmed and in "Track Key Engine Enabled Mode". We did the pulls first with the stock-exhaust LS (mine) so that we could capture very precise A/F values across the RPM range. We repeated the same careful procedure with the Black Key - noting precise A/F trends. The reason that we were so careful in testing the stock car first was that we knew we would *try* doing the header-equipped car with no tuning modifications - and traditionally, this might result in a lean condition. As such, we were ready to abandon the pull if we didn't like the A/F's. We were VERY PLEASANTLY SURPRISED that the wide-band equipped Boss ECU more than adjusted for the Headers!!! A/F's were pretty equivalent if not slightly richer than the OEM car in BOTH Track Key and Black Key modes. I will post some detailed A/F graphs a little later - we're using the daylight to get the same header set-up on my car - albeit this time with the CATs. Our conclusion is that you DO NOT need a tune for the headers as the A/F's are right on the money - and the HP/TQ is really there as indicated in the chart. Again, I hope the forum members can appreciate how significant this is. We're NOT talking about a peak HP/TQ benefit , yet a benefit across the ENTIRE RPM range!

That's good news.
- Have you/will you try adding an aftermarket CAI (& which one).
Many thanks for sharing your information.
This forum is at least one of if not the best I have joined.
 
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Maui
nota4re said:
Just completed the install of an entire Kook's exhaust system - from the long tube headers, Boss 302 specific H-pipe, and mufflers. Took this LS and an identical LS with a stock exhaust system and put them both on the dyno back to back. Here are the results from the Kook's. Very, very impressive that there is a very consistent gain across the ENTIRE rpm range. A very worthwhile modification in our opinion.

I'd post the graph if an admin tells/allows me to.

Was the kook's exhaust system you tested with cats or without? Would there be any noticeable difference in horsepower/torque gains between the system with cats compared to the one without?
 
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I mentioned this once before, but I'd like to know if a header/pipe/free flow cat setup has been tried in conjunction with a CAI, such as the Airfraid (sp?) unit.

..Also whether track key setup can be run with such h/p/cat with CAI.

Hennessy has a kit but the price is over the top, although at 492 hp power is OK (not sure about their torque).
 
Kendall--how did you get the long tubes installed? Drop the K-Member, or ?

Easy. I said, "Ryan, put those damn headers on the LS." I came back about 10 hours later and he was done! (Ryan's my son and mechanic extraordinaire. He's flying on Friday to do a Whipple upgrade on a Ford GT. Ford GT owners have flown him to other states to work on their cars - his favorite of which was Hawaii.) OK, yeah, I'm a proud dad - but let me answer your question.

We (Ryan doing and me mostly watching and criticizing) have done the install now on two different Boss 302's. We elected NOT to drop the K-member mostly because we're working on a 4-post lift. Easier than it sounds, but you do need to support and lift the motor and remove BOTH motor mounts completely. You install the driver's side header first (easier), lower the motor slightly, then install the passenger side header. There's a "trick" in that you can start all of the bolts holding the passenger side header, but with the header still loose you will need to lay the motor mount AND the starter kind of up in your way before tightening any of the header bolts. If you tighten one or more bolts on this passenger side before positioning the starter and motor mount - then you'll never get them in. The directions from Kook's are pretty good but we're guys and thought that after we did the driver's side, we didn't need the damn directions anymore! Guess again!
 
Was the kook's exhaust system you tested with cats or without? Would there be any noticeable difference in horsepower/torque gains between the system with cats compared to the one without?

The graphs posted thus far are from two different LS's. One was stock (mine) and the other one we had just installed the Kook's headers and exhaust on - with NO CATs.

Now, since that time, we have completed the Kook's install on my LS - WITH CATs, and we have dyno'd again to show the results. (Perhaps a moderator can help me to post those graphs??) Even with CATs, we have VERY good gains across the whole RPM range.
 
I think the one he used had cats. He would have needed a tuner if he used the off road H.

95blitz - We would have thought that a tune would be needed too - but we have proven, more than once now, that the OEM wideband-equipped ECU is compensating for the exhaust - and doing so very well. Our A/F's are even richer than stock in the rpm range from 4500 up! Pretty cool!!
 
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nota4re said:
Was the kook's exhaust system you tested with cats or without? Would there be any noticeable difference in horsepower/torque gains between the system with cats compared to the one without?

The graphs posted thus far are from two different LS's. One was stock (mine) and the other one we had just installed the Kook's headers and exhaust on - with NO CATs.

Now, since that time, we have completed the Kook's install on my LS - WITH CATs, and we have dyno'd again to show the results. (Perhaps a moderator can help me to post those graphs??) Even with CATs, we have VERY good gains across the whole RPM range.

Do you know if Kooks offers a low restriction CAT kit? (or others that do)
Thx.
 

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