[Sephx1]

Finally getting around to some upgrades on my son’s 2016 SS. Installing some ceramic coated Kooks 1-7/8” long tubes with green cats to go with the Borla S-type NPP. Also installing a Cold Air Inductions intake and DSX flex fuel kit since it will be getting tuned.

Not pictured is the 1LE short throw shifter I have in my spare parts we will be installing while we have everything opened up. If I’m dropping the transmission down it looks like the headers will go in easier.

Already installed the starter heat blanket and will be insulating the chassis wiring harness before the headers go in.

Looking for opinions on spark plugs since I have the stock AC Delco plugs out.

Also I bought the ARP header bolts which are really nice, but Kooks supplies stainless bolts with a locking clip on it. Not sure which would be better.

Thinking about doing a 160 degree thermostat too since I have the coolant level down.

[Judy1le]

Originally Posted by Sephx1

Finally getting around to some upgrades on my son’s 2016 SS. Installing some ceramic coated Kooks 1-7/8” long tubes with green cats to go with the Borla S-type NPP. Also installing a Cold Air Inductions intake and DSX flex fuel kit since it will be getting tuned.

Not pictured is the 1LE short throw shifter I have in my spare parts we will be installing while we have everything opened up. If I’m dropping the transmission down it looks like the headers will go in easier.

Already installed the starter heat blanket and will be insulating the chassis wiring harness before the headers go in.

Looking for opinions on spark plugs since I have the stock AC Delco plugs out.

Also I bought the ARP header bolts which are really nice, but Kooks supplies stainless bolts with a locking clip on it. Not sure which would be better.

Thinking about doing a 160 degree thermostat too since I have the coolant level down.

If you can swing it, go hurst short throw shifter instead. The 1LE shifter is only at 8-10% difference in throw. The hurst is ~45% shorter. I got the hurst installed on my 1le and its one of my favorite things I did too the car.

[Joshinator99]

Make sure you do the Katech thermostat (160 or 174). It’s the only aftermarket LT tstat brand that isn’t complete garbage (unless you convert to LS3 style which is overkil for a mostly stock SS).

[Mark114]

Originally Posted by Joshinator99

Make sure you do the Katech thermostat (160 or 174). It’s the only aftermarket LT tstat brand that isn’t complete garbage (unless you convert to LS3 style which is overkil for a mostly stock SS).

Are there tuning changes required with a lower temp thermostat?

Do you recommend a metal thermostat housing at the same time, or is that overkill for NA engine?

[Joshinator99]

Originally Posted by Mark114

Are there tuning changes required with a lower temp thermostat?

Do you recommend a metal thermostat housing at the same time, or is that overkill for NA engine?

Katech designed the 174 so that it would not need a tune change. The 160 needs a change in the tune (very easy with HP Tuners).

No harm in doing the AMP thermostat housing on an LT1 if you race the vehicle (but probably not needed), but a definite no brainer on supercharged LT1/LT4 cars since a blower belt breaking is a guaranteed formula for breaking the nipple off the OEM tstat housing and spraying coolant everywhere.

[adamjwilson]

Originally Posted by Joshinator99

Katech designed the 174 so that it would not need a tune change. The 160 needs a change in the tune (very easy with HP Tuners).

No harm in doing the AMP thermostat housing on an LT1 if you race the vehicle (but probably not needed), but a definite no brainer on supercharged LT1/LT4 cars since a blower belt breaking is a guaranteed formula for breaking the nipple off the OEM tstat housing and spraying coolant everywhere.

That AMP thermostat housing and 160* t-stat is the way to go. Super easy to tune in and for cooling fan to come on early.

[Sephx1]

Got the shifter in and headers on today. I used the 1LE shifter I already had in my spare parts. After discussing with my son, we decided at least he knows he likes the one in my ZLE. Lots of work to change it if he doesn’t.

The gaskets that come with the Kooks headers are junk. Fought them for a couple hours trying to get all of the bolts started before giving up and using new GM gaskets. Went on super easy after that. Decided to use the ARP bolts as well.

When I was trying to figure out why I was struggling with getting the header bolts in, I pulled the old manifolds back out for reference. I noticed one of the exhaust ports is not black like the others. Might be time for a leak down test.

[Smokin19]

I will second the AMP thermostat housing using their 160 deg thermostat. It even re- positions the smaller hose for a cleaner look. Don't want a broken belt taking out the housing.

[Sillysspeed]

Did you order the headers from kooks like that? Ceramic coated

[s346k]

i would use ngk tr5ix-11 plugs. i wouldnt bother with a thermostat. especially on ethanol, the car will have no problem keeping cool.

[Sephx1]

Originally Posted by Sillysspeed

Did you order the headers from kooks like that? Ceramic coated

No, I got a quote from Jet-Hot for over $800 and decided to get them done locally for $220.

Finished tonight, very happy with how it turned out. I will probably re-do the exhaust to cat connections, the sleeve clamps aren’t up to my standards. The only part of the Kooks package that was high quality was the headers themselves. The instructions for the DSX flex fuel kit were not very good, I could have wired it much quicker if they had been more detailed about the wire going to the ECU.

Looking forward to getting it dyno tuned by Nic D at Cordes Performance.

[cjperformance]

Originally Posted by Sephx1

Got the shifter in and headers on today. I used the 1LE shifter I already had in my spare parts. After discussing with my son, we decided at least he knows he likes the one in my ZLE. Lots of work to change it if he doesn’t.

The gaskets that come with the Kooks headers are junk. Fought them for a couple hours trying to get all of the bolts started before giving up and using new GM gaskets. Went on super easy after that. Decided to use the ARP bolts as well.

When I was trying to figure out why I was struggling with getting the header bolts in, I pulled the old manifolds back out for reference. I noticed one of the exhaust ports is not black like the others. Might be time for a leak down test.

When i changed plugs recently, i noticed the plug from that same cyl on mine had a very different color to it too compared to all the others... more ashy if i recall. Also had some (im guessing) oil on the plug threads. I have a thread in forced induction that shows the plugs. I can link it if interested.

My assumption at the moment is that the factory pcv system has a tendency to direct the blowby oil towards that cyl. I didnt pull exhaust manifolds or anything, but thought that info might be helpful. I did compression and leakdown and all was normal. I havent rechecked the new plugs yet, but i have a MM catch can installed now. Ill be interested to see if the same plug is different then the others next time i check.

Im betting the color is due to ash/burned oil on yours too.

[Sephx1]

Originally Posted by cjperformance

When i changed plugs recently, i noticed the plug from that same cyl on mine had a very different color to it too compared to all the others... more ashy if i recall. Also had some (im guessing) oil on the plug threads. I have a thread in forced induction that shows the plugs. I can link it if interested.

My assumption at the moment is that the factory pcv system has a tendency to direct the blowby oil towards that cyl. I didnt pull exhaust manifolds or anything, but thought that info might be helpful. I did compression and leakdown and all was normal. I havent rechecked the new plugs yet, but i have a MM catch can installed now. Ill be interested to see if the same plug is different then the others next time i check.

Im betting the color is due to ash/burned oil on yours too.

I hope you’re right and it’s nothing serious. I noticed oil on the threads of several of the spark plugs on the drivers side. We installed a catch can about 8,000 miles ago, and the plugs were changed around that time.

[Sephx1]

Originally Posted by 6spdhyperblue

Is cylinder 8 firing?

No codes, stumble or rough idle. I’m going to put a temp gun on all the header tubes next time I cold start it and see what they read.

Forgot to post the photo of the chassis harness insulation. I saw that subject has come up again in another thread.