Long Tube Headers and MidPipe

[SN69SH]

Hi- I looked through the site and really could not locate the answer I am needing. It has been 3 hours and I really am supposed to be working. lol

2015 ZL1 Auto. (only have a race tune, CAI and E2 catch can, oh a fuse pull)

Want to do long tube headers and off road x-pipe and pulleys. Do I further need injectors? Will I loose too much boost without upgrading the injectors?

If injectors are needed do I go to just the next level say 60 or 80?

I want a little more power, yet do not want to blow my car up. I am NOT doing a cam at this point. Just the headers, x-pipe and pulleys (like to do pulleys but don't have to). I would like to stay out of the boost-a-pump realm at this time however, if needed I can do it.

Any help would be appreciated.

[Kelly@PCMofNC]

Originally Posted by SN69SH

Hi- I looked through the site and really could not locate the answer I am needing. It has been 3 hours and I really am supposed to be working. lol

2015 ZL1 Auto. (only have a race tune, CAI and E2 catch can, oh a fuse pull)

Want to do long tube headers and off road x-pipe and pulleys. Do I further need injectors? Will I loose too much boost without upgrading the injectors?

If injectors are needed do I go to just the next level say 60 or 80?

You don't lose boost because of the injectors, you lose boost on account of the headers (engine breathing better via cam or heads or headers = less boost).

The short answer, yes, if you are doing headers and pulley(s) then you need injectors as well. Personally I would do a set of 850cc or 1000cc FIC's and be done with it - it'll support you now and then in the future as well when you turn up the boost further or if you add a cam.

Depending on how much boost you are adding you should also add a boost a pump at this point.

[SN69SH]

Thank you

[Can'tHave2MuchHP]

Definitely get a set of injectors, I and most others here will recommend ID850s or ID1050s. More than likely 850s will serve you just fine if you're never shooting for 800+ RWHP.

What pulleys are you doing? Without a cam, you're going to want to stick to 18% or 22.5% overdrive at most, otherwise you're really just wasting it and sending it out the exhaust (But you will find people running 30%+ over drive on stock cam and recommending, those who know what they're doing like Ted Jannetty know that you're really gaining nothing but heat). If you step over 18% overdrive, you'll need some kind of cooling upgrade or 2, especially in Texas. Ron Davis or AFCO heat exchanger will serve you well.

I'd recommend:
ID850s
Kooks or ARH headers if you can afford them, cat-less mid pipe
Lingenfelter 9.17" or 9.55" lower pulley, ATI Damper, and ARP bolt (Crank bolts are throwaways) (You'll also need either a idler relocation bracket or smaller idlers)
Tune by a good shop, of which you have lots of access to in Texas.

In the future if you want more, then I'd look at porting the supercharger and snout, as well as a throttle body upgrade. After that, you'll need to go with a cam/heads and stuff. Meth and E85 too.

[ZL1 FOR ME]

SN69SH that is a real good looking car.

[SN69SH]

Thank you

[SN69SH]

Thanks this helps. I have been doing a ton of research and I already need a heat exchanger regardless of what else I do. I live in Texas and I'm heatsoaked after maybe two runs. Winter not so bad. On a long road course no issues just drag strip. (Except for brakes lol learned the hard way GM skimped there.)

In addition to the heat exchanger the injectors and pulleys it seems I need belts etc as well.

Way back...lol I heard an idea of just adding fuel injectors instead or replacing the stock units. It may be more costly as I haven't checked if there is a kit. Has anyone done this? I'm assuming although cannot confirm the stock injectors are 42?

I will need the BAP or the like an inline or something. I'm not sure I want to go all out fuel cell at this point. Lol

[SN69SH]

I apologize I wrote it wrong in my original post. I do understand I lose boost with the headers along with torque. I just misspoke in the email.

Have you heard of just adding fuel injectors instead of replacing?

[JB'sZL1]

Originally Posted by SN69SH

I apologize I wrote it wrong in my original post. I do understand I lose boost with the headers along with torque. I just misspoke in the email.

Have you heard of just adding fuel injectors instead of replacing?

???

[ZMEnow]

Only if you are adding cylinders..

[RLHMARINES]

Originally Posted by SN69SH

I apologize I wrote it wrong in my original post. I do understand I lose boost with the headers along with torque. I just misspoke in the email.

Have you heard of just adding fuel injectors instead of replacing?

Loosing boost because you've upgraded to headers, ported heads, ported intake, ported blower, and or cams is not a bad thing. Boost for the most part is just a measurement (psi) of air restriction in our forced induction cars.

We think of increasing power easily (cheapest route) by increasing boost from spinning the blower faster with pulley upgrades but this will also generate more heat which is not a good thing. You will have to counteract the heat by upgrading your heat exchanger and maybe also a chiller system if your into drag racing to keep the temps in check between runs.

Headers and free flowing exhaust along with some engine porting work and maybe a cam (more expensive route) also if you like will lower some of the air restrictions (psi) but your hp and torque will see a great improvement.

You will need to upgrade and replace your injectors and maybe additional pump flow for the appropriate hp level to keep the injector duty cycle in a safe percentage so as you keep from leaning out you fuel which as we know if you lean it out to too much it will burn a piston or worst.

I hope I've said it correctly in my post and lf not l hope others with more technical knowledge can step in and correct anything l may have gotten wrong. I hope this helps and not further confuse you.

[RLHMARINES]

Originally Posted by SN69SH

I apologize I wrote it wrong in my original post. I do understand I lose boost with the headers along with torque. I just misspoke in the email.

Have you heard of just adding fuel injectors instead of replacing?

You're thinking more along the line of a naturally aspirated engine loosing torque down low if you increase the exhaust size too much especially in something heavy like a Tahoe with a 5.3 V8 going from a single muffler exhaust to a true dual muffler setup. Back pressure is what is at play here and a single 3" exhaust is best for that given na engine and weight setup.

[SN69SH]

Thank you so very much.

[Misterleeman]

I'd recommend the 1050's. If in the future you decide to go with E85, then the 850's will be too small. The in-line pump is the way to go - it will also support E85 demands.