B&B "Shorty" Headers into a C5: How-To and Results [Archive] - SmokinVette.com Forums

: B&B "Shorty" Headers into a C5: How-To and Results


powerlabs
09-24-2009, 08:33 PM
I lent my neighbor a hand at installing his B&B Short Tube Headers. The install was *considerably* more involved than the "3 hours" the instructions manual (all one page of it :lol: ) claim, so I figured I'd do a quick write up to help out anyone else planning this mod.

Having done headers on my own car (a C6), I figured this would be as easy as that was; when I installed Kooks 1 3/4 long tube headers with a catted X-Pipe on my C6 (http://www.smokinvette.com/corvetteforum/showthread.php?p=292471#post292471), all I had to do was take a good look at how the factory headers bolted on, and then spend no more than 5 hours removing everything and assembling the complete Kooks system. I did a write up on that install which you can find on the C6 forum here:
That was not the case. I tried to work around certain items only to find out they absolutely did have to come out. I will do the write up the correct way.

Also, note that VetteWeb has a decent write up with pictures (http://www.vetteweb.com/tech/0501vet_b_and_b_performance_exhaust/index.html) that you can refer to as well.

Before we began, all exhaust bolts were sprayed with "PB Blaster"; exhaust bolts are notorious for seizing and this usually helps prevent that. Despite the PB blaster we still HAD to shear off one of the bottom flange bolts (luckily they are not reused on this install). I imagine we would have sheared more if we hadn't done that.
First and foremost, remove the following (they all have to come off before the headers will come out of the car, so you may as well do it now while the car is on the ground):
Engine covers (the pop right out)
All plug wires (they can be VERY hard to remove from the block. Be sure not to pull from the wire. On some I had to use a screwdriver as a prybar from underneath the car to pop them off. Others required careful use of pliers on the rubber boot).
Coil packs (4 bolts and a plug)
Alternator (1 wire, a plug, and 2 bolts. Have a friend use a prybar with a socket on the belt tensioner (which is at the passenger side end of the accesories belt) so you can get the belt off before you try to pull the 2 bolts that hold the alternator in place).
Dipstick (1 bolt)
Drivers side EGR (Exhaust Gas Recirculation) valve. Pull that whole sucker off. This requires you to unbolt the flange that holds it into the headers, then undo the hose clips at both ends of its hoses and pull the hoses off.
Also pop the vacuum hose off the brake vacuum reservoir and pull it out of the way.
NOW you can begin.
We started with the drivers side. Once everything is out of the way, you can use a 10mm wrench with an extension to get the bolts out of the way... Except for one:

http://www.powerlabs.org/images/c5/c5headers%20(1).JPG
(Look carefully at where the wrench is attached to).
We called that the "bitch bolt". It was UNREAL. That little sucker is holding the end of the drivers side header, closest to the firewall. No wrench would fit in there; it is against the firewall, underneath the windshield, next to the brake vacuum reservoir and the header itself. There is literally NO space for your hands to fit in there,and about 1/2" of wrench travel. It sucked.

Those bolts removed, you can now move on to the passenger side. That is considerably easier. The one thing to watch out for on both sides is that there is a bolt underneath the EGR flange that is hard to spot. You can see it here:
http://www.powerlabs.org/images/c5/c5headers%20(10).JPG
Make sure you remove that one too... Otherwise the headers won't come off ;)

Now that both headers are lose off the engine, jack the front of the car up and support it safely by two jackstands. The headers come out from the top, so the height you need here is whatever it takes for you to be comfortable underneath the car.
For this install we supported the front end of the car by two jackstands on the engine crossmember, and then left the 3 ton hydraulic jack on the center of the crossmember. You can never be too safe.
I will add here that I found it VERY uncomfortable to be working pushed up against the wheels, and eventually had to remove the passenger side wheel to get that side in. I would also recommend removing both front wheels to make the job easier.
Now you can crawl underneath the car and disconnect the O2 sensor from its harness. You should also remove the O2 sensors, but I found this impossible with the wrench I had. A different wrench might have done the trick, but I just pulled them out with the headers.
Once the O2s are disconnected, undo the 3 bolt flange that bolts the factory headers to the factory catalytic converter. The headers are now free. Carefully pull them out from the top of the car.

http://www.powerlabs.org/images/c5/c5headers%20(2).JPG

Now I removed the O2 sensor from the factory headers, carefully applied anti-seize to its threads (making SURE not to get any on the sensor itself; this will destroy the sensor), and torqued them both down to the new headers. The shorties slide right in to the car.
The factory gasket can be re-used. Make sure to carefully scrape off any residue from it and the heads beforehand though. Also, clean the header bolts and apply a dab of anti-seize to them. Now you can bolt the headers on.
The easiest way to do that is having someone hold the headers while you get the bolts started. Make sure to start every bolt by hand so no cross threading occurs. Don't tighten them in all the way before doing the bottom flange.
Once all header bolts have been started, go underneath the car again and re-connect the O2 sensor plug, then tighten the 3 flange bolts. I found that I could start the drivers side by hand, but getting the passenger side bolts in required me to carefully push the exhaust up with a car jack untill both side mated. I then torqued all flange bolts to 35 ft-lbs. Now the car can be lowered.

With the car back on the ground, carefully torque the top header bolts from the center, moving outwards, to 15 ft-lbs.
Then re-install the coil packs, alternator and EGR valve:

http://www.powerlabs.org/images/c5/c5headers%20(9).JPG

On the passenger side, you will find that the dipstick flange hits the header. Use a file or a dremel tool to shave the flange down by about 1/8". I used a dremel and it took a few seconds. It will now bolt right up:
http://www.powerlabs.org/images/c5/c5headers%20(12).JPG

Re-install the valve covers,
http://www.powerlabs.org/images/c5/c5headers%20(14).JPG

Now we re-installed the wheels, lowered the car (we didn't before so getting any bolts we dropped to the floor would be easier) and torqued the lug nuts to 100ft-lbs. Double checked everything and fired it up. You will notice a LOT of smoke as the PB blaster, anti seize and any other oils burn off.

powerlabs
09-24-2009, 08:34 PM
Short tube headers are a compromise dictated by Federal emissions laws which state that it is a federal offence to alter the location of the factory catalytic converters in any vehicle. Yes, they won't make as much power as long tubes, but these are CARB certified and will pass emissions everywhere... Unfortunately you definitely pay for that certification; these little guys were expensive! Lets see what we get for our money:

http://www.powerlabs.org/images/c5/c5headers%20(4).JPG
These headers are JetHot coated: I would never put uncoated headers in any of my vehicles; the thin wall tubing radiates way too much heat, making underhood temperatures soar and everything rubber and plastic dries up and embrittles around them. Plus by wasting heat you also lose exhaust gas velocity, which translates into power loss. The fact that they look stunning and will continue to do so for years to come is another plus ;)
Notice the nice smooth bends, and the fact that the leftmost runner has been lengthened in an attempt to make them as close to equal-length as possible. I like that a lot.!
Overall build quality is also very good.

http://www.powerlabs.org/images/c5/c5headers%20(5).JPG
Factory header port. Cast iron mass produced...

http://www.powerlabs.org/images/c5/c5headers%20(6).JPG
B&B header port... Larger, smoother, and carefully hand ported for smooth bends.

http://www.powerlabs.org/images/c5/c5headers%20(7).JPG
Factory collector, if you can call it that... Each runner merges in at a different spot.

http://www.powerlabs.org/images/c5/c5headers%20(8).JPG
4-into-1 B&B collector... Not quite as nice as Kooks, but MUCH better than factory.

Now my driving impressions:
The exhaust note didn't change as much as I expected. There is some more exhaust "Burble", and it sounds, perhaps, "throatier" but overall the sound is very subtle. On the other hand, there is also zero drone, which is very nice.
Power wise, I must say I was quite impressed!

powerlabs
09-24-2009, 08:36 PM
The 'Vette:
2003 50th Anniversary Edition A4 3.15 Axle

The Power mods:
Dual Cone Intake
Smooth Coupler (intake to TB)
B&B Short Tube Headers, JetHot Coated
Flowmasters Exhaust

The goal is daily driven, factory reliable horsepower on 91 octane; to that effect all mods are CARB legal. No long tubes, cams, headworks, etc, at least for now.

Initially, the car was "tuned" with a handheld programmer. This improved the throttle response and, particularly, the firmness of the shifts; namely the car would now "bark" the tires going from 1st to 2nd. It felt "fast". But, was there power left on the table?

Enter Charlie at RPM motors:
http://www.powerlabs.org/images/les1.JPG

With the mods above and the "canned tune" from the handheld programmer, the results were as follows:

302WHP / 328WTQ on a DynoMite eddy current brake dyno. This represents approximately a 17whp gain over what a factory C5 A4 baselines on that dyno with no mods or tune.
Disappointed with the results, the owner decided to have Charlie work some of his magic using HP tuners.

The results speak for themselves:
http://www.powerlabs.org/images/les's.JPG

outjPCc238g

It should be noted that Charlie doesn't claim credit for the entire 29whp gain; he is fairly confident that the car would have made MORE power without the handheld tuner being installed... But we won't go there on this forum ;)
P.S. This isn't my car ;) I'm just helping my good friend and neighbor Les (50th@50) make power. You can see our header install thread

Stop Light King
09-25-2009, 08:06 AM
To bad I don't own a C5, but saw the thread and had to make a comment :thumbsup: :thumbsup: :thumbsup:

powerlabs
09-25-2009, 09:34 AM
To bad I don't own a C5, but saw the thread and had to make a comment :thumbsup: :thumbsup: :thumbsup:

I have a write-up on C6 headers too... I own a C6 ;)

Dunkin
09-25-2009, 10:43 AM
I have a write-up on C6 headers too... I own a C6 ;)

Is it posted here? :thumbsup:

bigblock427
09-25-2009, 10:53 AM
Powerlabs, very nice post. Thanks for taking the time to share it with us.:thumbsup3:

powerlabs
09-25-2009, 11:15 AM
Is it posted here? :thumbsup:

Yes. Here you go:

http://www.smokinvette.com/corvetteforum/showthread.php?p=292471#post292471

Lethal Tendencies
09-27-2009, 06:42 AM
Excellent write-up.Thanks for the info.

madmatt9471
04-26-2011, 02:22 PM
It's been a while but very good write-up!

Thanks,Matt

Bucwheat
06-29-2011, 10:34 AM
Great writeup Powerlabs.:thumbsup3: