Kooks 1 5/8 headers before and after

[Jumpmaster2015]

Don't recall hearing any quality or performance complaints from people who have installed Kooks. The same cannot be said for too many others. I know my BBK's were and absolute PIA to install, but the results made it worth while. But,...if I were to do it all over again....well, nevermind.
I think you made a good decision. Be sure and post up your impressions good or bad.

Beefcake is a standup dude. He found out Kooks was slowing things down, and got me a tracking number today! He wound up getting them shipped right now, when Kooks wanted them to wait on a bulk shipment to a Nevada warehouse for another week or so. It was probably just a breakdown in the system somewhere. Happy to be on track again.

 

[Turbo06gt33]

I did a before and after when I installed headers on my CJ auto car. Car had CJ, 65mm throttle body, jlt, upr off road x-pipe, driveshaft e85. Made 427whp and 370wtrq. Only change was installing the kooks 1 7/8th headers and their off road x-pipe same tune. Made 443whp and 390wtrq. Same dyno different day so take that into consideration.

 

[Jumpmaster2015]

So today was the day. Baselined at 433 on the mustang dyno. The shop installed the headers, no obvious leaks, ran the file, and I lost 13 horsepower down to 420. It was the end of the day so decided to call it quits for now. Any idea of wtf I should do?

 

[Jumpmaster2015]

Thinking about running the previous tune file

 

[Coz]

Did your torque curve improve at any point?

 

[Jumpmaster2015]

Did your torque curve improve at any point?

Yes, at some point I gained 3-5 it looks like. I do not have graphs yet hopefully tomorrow I will

 

[Coz]

Certainly not enough of a trade-off to warrant losing 13hp.

 

[Jumpmaster2015]

Certainly not enough of a trade-off to warrant losing 13hp.

Well the car drove like a slug from the shop to dinner. I switched back to the original tune file in the park lot and its quicker than before. Im going to a dyno jet after maybe getting another revision.

 

[Jumpmaster2015]

Quicker as in faster than it was in 433 hp mode, she freaking halls ass. I have hope now

 

[sur_real1]

Was it re-tuned with the new headers? Does the hp run out longer up top or does it fall off at the same spot before the headers? I know that there is a lot of discussion back and forth on the 1 5/8" as being enough for these motors, but these heads, even in stock form for its displacement, flow enough air that 1 5/8" seems a bit small. Of course, this is just an opinion based on as much research I can get my hands on.

Of note, I ran 1 5/8" on my N/A 99 Cobra 4.6 valve, and they seemed perfect. But of course that was a 281 with much lower flowing heads and no ti-vct.

Can you post the before and after dyno numbers? Maybe it is just a fluke, as long as the car is running right and not having any issues.

 

[Jumpmaster2015]

I am waiting on the graphs. Also, shaun brought up an excellent point of false knock. I wish I had thought of this, but I was pretty bummed lol. I am currently working with the shop to hopefully have the install work looked at again, this time by the tuner who was out of the shop yesterday.

 

[sur_real1]

Oh yea, false knock could definitely cause issues too. That was a huge problem on the new edge four valves as well. And of course, understandably, disabling knock sensors is a touchy subject.

 

[Jumpmaster2015]

Oh yea, false knock could definitely cause issues too. That was a huge problem on the new edge four valves as well. And of course, understandably, disabling knock sensors is a touchy subject.

Yeah im not doing that lol. I am going to pull a wot data log later to see what those knock sensors are up to. If they are fine then I will visit a dyno jet on the new tuning file. I feel a ton of down low power now that I switched the file

 

[Jumpmaster2015]

baseline, 433 corrected

 

[Jumpmaster2015]

I have the final 420 in a video, but I was so pissed at that point I didnt bother taking a picture

 

[corepwn]

Brutal. Hope it gets sorted.

 

[Jumpmaster2015]

Brutal. Hope it gets sorted.

Going to an exhaust shop to fix any obvious mistakes, and then ill pull a datalog. I hope its clean!

 

[Riddick]

The locking style faster kooks use will rattle. When I did my install Shaun recommended to loosen the bolt with the locking fastener so it's tight against the header flange and then install the locking clip. This will stop it from moving around and possible pulling timing. The clips will still rattle, I'm tempted to remove the fastener all together.

Sent from my XT1097 using Tapatalk

 

[Jumpmaster2015]

The locking style faster kooks use will rattle. When I did my install Shaun recommended to loosen the bolt with the locking fastener so it's tight against the header flange and then install the locking clip. This will stop it from moving around and possible pulling timing. The clips will still rattle, I'm tempted to remove the fastener all together.

Sent from my XT1097 using Tapatalk

Just had the car up on a lift. No leaks, no rattling, no metal on metal contact. Everything looks good.

 

[Jumpmaster2015]

So here is a datalog that I just pulled. There is a little bit of positive knock at the beginning when I stomped on the pedal, but the engine stalled at that point as well.