header questions ?

[kinpin]

I am running stock manifolds with cat delete pips and stock exhaust.
With my mods I am running 14.1 pound of boost at peak .

1, if I put on a pair of KOOKs headers and off road pips . Will that lower my boost ? if so how much ?

2. if I have the headers coated with a 2000+ degree coating will that keep the engine bay cooler then the stock manifolds ?

3. Will the headers make the exhaust sound loader in the cabin ? then the manifold ?

4 When running header and off road pips and stock exhaust is there a lot of droning sound ?

[WVracer]

1. Yes it should lower boost, I don't know exactly how much. Around 2 lbs I would say.
2. Don't know, but I would imagine so.
3. Yes, very much so. Headers make these cars extremely loud.
4. Yes there will be a good bit of drone once it hits the certain resonance RPM, thats why I went with Corsa, I don't have cats and I have absolutely no drone.

[Can'tHave2MuchHP]

1, if I put on a pair of KOOKs headers and off road pips . Will that lower my boost ? if so how much ?

2. if I have the headers coated with a 2000+ degree coating will that keep the engine bay cooler then the stock manifolds ?

3. Will the headers make the exhaust sound loader in the cabin ? then the manifold ?

4 When running header and off road pips and stock exhaust is there a lot of droning sound ?

1) It will lower the boost PRESSURE inside of the engine, however, you do not lose HP from that. In other words, say that 1 pound of boost is worth roughly 20 HP. Lets say you lose 2 pounds of boost. Well, you do NOT lose 40 HP. And if you only lose 1 pound then again you will not lose 20 HP. Headers only add power and make your engine more efficient. Period.

2) Probably not. But maybe.

3) Yes, the exhaust will be louder but you already have the cats deleted, so there's not much sound to be gained from changing the manifold to a Header style. It will sound good paired with the stock NPP exhaust and you'll have the ability to run the valves open or closed on the mufflers depending on what volume you're after.

4) There's likely some drone but I do not think they drone much, if they did then there's no way it would be the most popular ZL1 exhaust setup (Which it is, probably by a power of 4 to anything else).

I say do it and don't look back. You'll have to get her tuned though so if there's any other mods you want to bundle in like a Pulley or Intake/Throttle body etc. then do it at the same time.

[kinpin]

Originally Posted by WVracer

1. Yes it should lower boost, I don't know exactly how much. Around 2 lbs I would say.
2. Don't know, but I would imagine so.
3. Yes, very much so. Headers make these cars extremely loud.
4. Yes there will be a good bit of drone once it hits the certain resonance RPM, thats why I went with Corsa, I don't have cats and I have absolutely no drone.

what Corsa did you go with ?

[Can'tHave2MuchHP]

Originally Posted by kinpin

what Corsa did you go with ?

There's only one option for Corsa on the ZL1, the sport 3" system and it sounds awesome. However, Corsa's zero drone policy is based on stock headers/cats. If you have are running headers/no cats/high flow cats then it will drone a little bit, though probably less than stock. It will be WAYYYYYY louder than stock though I can tell you that. LSA + Headers + No cats + Corsa 3" is as loud as you're going to get an LS engine. You have no valves to close either. It's going to scream all the time unless you keep the RPM's under 3000. If you hammer on it, everyone for 2 miles+ is going to know.

[WVracer]

Originally Posted by Can'tHave2MuchHP

There's only one option for Corsa on the ZL1, the sport 3" system and it sounds awesome. However, Corsa's zero drone policy is based on stock headers/cats. If you have are running headers/no cats/high flow cats then it will drone a little bit, though probably less than stock. It will be WAYYYYYY louder than stock though I can tell you that. LSA + Headers + No cats + Corsa 3" is as loud as you're going to get an LS engine. You have no valves to close either. It's going to scream all the time unless you keep the RPM's under 3000. If you hammer on it, everyone for 2 miles+ is going to know.

Mine is pretty tame sounding, until you get on it. No drone at all in cabin, even with headers, and no cats. Now I agree, once you step on it, every cop in the tri-state area is gonna be looking for you. lol

[Can'tHave2MuchHP]

Originally Posted by WVracer

Mine is pretty tame sounding, until you get on it. No drone at all in cabin, even with headers, and no cats. Now I agree, once you step on it, every cop in the tri-state area is gonna be looking for you. lol

Yeah I rode in a Cammed ZL1 with Headers + no cats + Corsa and it sounded awesome and like typical Corsa it is an expertly tuned setup that is manageable if you keep the RPM's in "cruising" range. But yeah, WOT and she SCREAMS. Also had seat time in a ZR1 with the same setup (No cats, headers, corsa, cammed) and same thing, great cruising sound and idle, manageable levels. But WOT and the whole area code knows. When he left the party at my place, he jumped on it off a stop light about half a mile down the road from me and it was bordering on REALLY loud even from that far away (As in, sounded like the car could have been in my driveway).

[kinpin]

Thank you all for the info

[JBZL1]

I have headers, no cats and npp stock cat back with the fuse pulled and I love it ! If I'm just cruising around and easy on the throttle it's not bad for drone .... but at W.O.T it's barbaric !!!!!!!!! I love it

[winterboy8]

"Will there be drone" is a very subjective question. I loved mine with 2" ARH, catless and stock cat-back, no drone in my opinion. When I swapped the cat-back is when I was no longer happy. If I had to do over again, I'd do long tubes, catless or high flow cats and stock exhaust.

[Quicklsa]

Just threw on 2" texas speed headers with off road connection pipes and it's a very big difference probably more than just doing a cat back and no headers.i do have to say that's it sounds amazing, it gives the car a sound it deserves.