'17 V6 Build - I bought a Mustang?!?!?!

[ctandc72]

I'm not too worried about the long tubes being loud. I'm running a MBRP Cat back exhaust (meant for the GT). It sounded great when the car was stock. Once I installed the shorty headers, it got raspy only towards WOT. I installed (2) Vibrant Ultra Quiet resonators and it sounds great now. Actually could go a bit louder and it would probably sound even better with the long tubes and cats being gone. Worse case? It's too loud and I add some small cats or resonators to the mid pipe....which I was thinking of doing anyway. $220 difference between catted and off road pipe and I can get two small stainless cats for less than $100 and my exhaust guy would charge me $50 to weld 'em on.

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[USMCtoARMY]

I'm not too worried about the long tubes being loud. I'm running a MBRP Cat back exhaust (meant for the GT). It sounded great when the car was stock. Once I installed the shorty headers, it got raspy only towards WOT. I installed (2) Vibrant Ultra Quiet resonators and it sounds great now. Actually could go a bit louder and it would probably sound even better with the long tubes and cats being gone. Worse case? It's too loud and I add some small cats or resonators to the mid pipe....which I was thinking of doing anyway. $220 difference between catted and off road pipe and I can get two small stainless cats for less than $100 and my exhaust guy would charge me $50 to weld 'em on.

I think you will love them, but I think you will end up putting an extra set of resonators on them. Cant wait to some pics of them installed. You have ported intakes too?

 

[ctandc72]

I think you will love them, but I think you will end up putting an extra set of resonators on them. Cant wait to some pics of them installed. You have ported intakes too?

Yes.

 

[ctandc72]

Just finished installing the long tubes and off road h pipe. Waiting on the revised / updated MPT tune file to load to the car, currently at 27%.

No surprises on install really since I already did the shorty headers. I'm literally amazed how well the long tubes fit. I did drop the starter (2 bolts takes no time) as I did last time - better access to headers bolts on lower passenger side. I also took off the 10mm bolt that holds the metal coolant pipe on the pass side - easy and gives more room - I have big hands.

The mid pipe took some persuasion to fit snug into the oem exhaust clamps to my MBRP cat back. Dead blow hammer took care of that. Installed collectors studs / nuts loosely, installed header bolts loosely - everything JUST on until the exhaust was lined up. Then tightened down everything.

I used extenders / defoulers for the downstream sensors. Did NOT end up needing the BBK extensions for these rear sensors. Took the factory loom off the mount on the side of my 6 speed and they were perfect in length. You do need the upstream extensions - and they look OEM quality. You will need to order the 15-17 extensions - the ones that come with the headers are for the 11-14.

Did a start before tuning to check for leaks - all good so far. Yes a bit louder - but deeper and not raspy at all. YMMV - I have a GT MBRP street catback with (2) Vibrant ultra quiet resonators installed. WOT sounds nasty - as in good.

Waiting on the tune finish now

 

[ctandc72]

Well the new tune loaded - but the SCT tuner stuck on "clearing DTC codes". Unplugged it - car started fine, but the the tuner wouldn't pull the vehicle info so I could verify the tune loaded correctly. Got an error code. So now I'm flashing back to stock, then I can finish updating the tune, load the tune file then tune again.

Pain in the ass. Glad I thought to plug up the battery tender while I was doing all this.

Will post again after I've got the tune loaded and gone for a test drive.

 

[ctandc72]

Almost done updating the SCT tuner. 751 update files. Jeez.

 

[ctandc72]

Tune loaded. Test drive to get gas completed.
Yup - it's loud. But only from about 4K and on. Not raspy. Just loud. Cruising mildly through the gears, sounds GOOD. No rasp. No drone. WOT sings.

I'm sure there are people who would leave it be. But I beat on the car daily - so a little less volume is good for me.

Looking for two 2.5" bullet cats right now. Get them welded in next week.

Just ordered two of these:
https://www.amazon.com/gp/product/B01N41NJIP/ref=ppx_od_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

And it gained power - down low up through WOT.

 

[ctandc72]

 

[USMCtoARMY]

Very nice.

 

[ctandc72]

Figured I do a little write up on installing headers on the V6. Haven't really seen any decent ones for the S550. Most of this will apply whether you are installing shorty headers or long tubes.

While I have done plenty of work on all types of cars on hoists / lifts (and I actually plan on installing a lift hopefully by end of Summer) this job is very doable with jack stands and a floor jack. I'm well over 40 years old and I did it.

Time frame: If you've done headers before, you are ahead of the curve. For this install, I had the car in my shop with the heater running (it was cold) and I took multiple breaks to eat, etc etc. Honest estimate, if I had to make good time, I could install these in a 3-4 hours.

Tools : Make your life easier. Get some stubby ratcheting wrenches and some ratcheting wrenches with the angled head. Get a swivel and plenty of extensions for your ratchet.

- Start loosening headers bolts BEFORE jacking it up. I'm well over 6' and even I did this. I was taking shorty headers off for long tubes here - but I also installed the shorty headers - so it all pretty much applies. If you are shorter you're going to need a stool etc to get to these header bolts once you'v jacked the car up.

- Go ahead and remove the negative battery cable. Takes 2 minutes and worth it for when you drop the starter.

- Remove all the header bolts you can from the top. Don't freak out if the entire stud comes out when removing the nuts. It's not a deal breaker. Granted I plan on eventually replacing all the studs with bolts (more room clearances) and I want to replace the factory bolts with grade 8 stainless

- On the passenger side it was greatly beneficial to me (I have large hands) to remove the 10mm bolt holding the metal coolant pipe in place above the passenger side exhaust manifold / header. You can then pop off the plastic mount that holds the coolant pipe towards the front of the engine. It gives you a lot more wiggle room to be able to move that pipe around and it takes no time at all.

- Unplugging the factory 02 sensor plugs. Driver's side is right there at the back of the engine. Find the tab you can push on. Keep pushing until you feel it click, it'll come right out after that. Same for the passenger side but it was easier for me to get this loose when I was underneath the car, YMMV.

- Now get it up in the air. Jacking rails greatly help here because they allow you to jack up the car on the rail, and still have room to use the factory jacking points for placing the jack stands. Normally I'll jack up the front, get it on jack stands, then jack up the rear (using the rear end pumpkin) in one go - placing the rear jack stands under the factory rear jacking points. Once the car is up and STABLE (make sure every jack stand is at the same height in the front and in the rear) I normally use the jacking rails again and go up higher in the front. The more room the better.

- Get your extensions, socket and swivel and remove the two nuts on each manifold / shorty header where the mid pipe bolts up. Let it hang loose from the OEM clamps going to the cat back.

- Now disconnect the rear 02 sensor harnesses. TIP: If you are doing shorty headers that bolt up to stock mid pipe you don't even need to remove the mid pipe if you don't want. It's tight, but the shorty headers will drop in from the top. You'll just need to loosen the OEM clamps where the mid pipe slips into the cat back. That means you can leave these 02 sensors plugged up.

If you are doing long tubes / removing the mid pipe - the rear 02 harnesses are held in by a plastic stud / clip that mounts onto the side of the transmission (this is for a 6 speed manual - you auto guys have to see what you're working with) you can push this stud out of the mount, which gives you slack in the harness - they are held in place by the same clip arrangement as the front. If you are having trouble getting them loose DO NOT break out the screwdriver. Just push on the tab as close to the outside end as you can until you hear / feel the click of the tab releasing and pull the connector out.

- Now use a 15mm deep well and loosen the two bolts on each exhaust clamp that holds the mid pipe to the cat back.

- Remove the mid pipe and put it out of your way

- Get underneath. Start on the passenger side. Remove the two 13/14mm bolts holding the starter in. Literally takes 2 minutes. The way the factory starter wiring harness is run, you can let the starter hang, it will not damage the smaller wires the main harness is mounted and will hold it without issues.

- Remove the header / exhaust nuts you weren't able to reach from the top. The short / angled ratchet wrenches earn their pay check here. Once it's off, remove the header. It'll come out easy from the bottom with the starter gone.

- Move to the driver's side. Same deal. Pretty sure I removed this header / manifold from the top both times.

- If you are keeping the stock mid pipe skip this: Otherwise, use a 22mm wrench, 02 sensor socket or crescent wrench (be careful not to round the wrench flats on the 02 sensor) remove the 02 sensors from the mid pipe. Keep track of the upstream (front) and downstream (rear - after cat) sensors. FYI: 6 pin connector is front, 4 pin is rear.

- Now pick a side and either drop the header in (Shorty) or place the long tube in from the bottom. If you have an aftermarket bottom brace (like the 2 point Steeda I have) you'll need to remove this to get the long tubes in.

GASKETS - I left the OEM metal gaskets in place during my both my header installs with no leaks or issues.

- Hang the new header from the studs. If you had a few come out when you removed the headers, still no worries. Just screw those back in like a bolt. If the nut was frozen on the stud enough to pull the stud out - they will work fine for installing.

TIP: Personally I don't fully tighten the headers at this point. I didn't have this issue with the long tubes, but the shorty headers needed some "juggling around" to mate up to the stock mid pipe and having these installed loosely allowed some more wiggle room to make sure everything without binding up.

SHORTY HEADERS: Slip the stock mid pipe into the OEM exhaust clamps where it goes to to the cat back. A dead blow hammer can help if you have an aftermarket cat back or just need more clearance to get the header collectors to mate up to the mid pipe. Don't fully tighten the clamps yet - and just LOOSELY install the nuts holding the stock mid pipe to the collectors. Once everything is lined up and loosely bolted up, tighten the headers bolts all the way down on both sides, tighten the collector to mid pipe connections then tighten the clamp to cat back connections. Don't forget to reconnect all your 02 sensor harnesses and put them back where they came from.

LONG TUBES: Once you have the header hanging on the studs, loosely install all the bolts. Do the other side. Then using a bit of anti-seize on the threads (don't get it on the sensor tip itself) install the front 02 sensors onto the collectors of the headers. You'll need the 15-17 6 pin front sensor BBK extensions. You can also use any brand of 15-17 GT 5.0 front sensor extensions - the connectors are identical. I personally plugged the extensions into the factory connections for the front sensors, then routed them behind existing harnesses on each side that kept the wires running against the transmission / bellhousing and kept it well away from the exhaust. I used a few cable ties as needed to keep in cleanly mounted - but still leaving SOME slack as the entire thing does move around a bit.

Mount the defoulers / extensions for the rear 02 sensors in the mid pipe. I used these and haven't thrown a code, even before I flashed my updated MPT tune. Then install the rear sensors (again a bit of anti-seize NOT a lot).

- Test fit the mid pipe. The BBK off road pipe I used fit REALLY snug in the OEM exhaust clamps going to my MBRP GT catback. I totally removed the nuts from the clamps - slid the clamps on the cat back as far as they'd go, then I used a dead blow hammer to seat the mid pipe in the clamps.

- Now install the studs / nuts that hold the collectors of the headers to the mid pipe. The BBK provided studs have both sides of the studs threaded. The shorter side (threads) goes through the hold in the collector on the pipe and THREADS into the header collector itself. Flush to the other side was fine. Loosely install the washer / locknut / nut and do it on both sides, making sure everything lines up.

- Plug up the rear 02 sensors :I personally did NOT use the rear extender harnesses. I just used a couple of cable ties and didn't put the factory connectors back into the mounts on the transmission. I ran them with the extensions but they were way too long and would have required even more cable ties. Again YMMV

Tighten everything down.

Install the starter.

Drop the car down off the stands, tighten the bolts up top on the headers as needed.

Reinstall the coolant pipe bolt and clip. Install the negative battery cable.

Fire it up.

Hopes this helps.

 

[ctandc72]

So I had already ordered the universal cats I listed above when I decided to go out and measure the BBK off road pipe. Ended up ordering these:

https://www.amazon.com/gp/product/B009UODJI2/ref=ppx_yo_dt_b_asin_title_o00__o00_s00?ie=UTF8&psc=1

Got them put on this morning. The car sounds ridiculously good right now. My exhaust guy couldn't believe how good it sounded and he's been doing everything from imports to high HP cars for years. I'll try and talk my GF into using her phone so I can get a good drive by video. No drone, no rasp. Very little noises inside the cabin at cruise speed. Sounds flat wicked on WOT.

As far as power differences. I am running the 91 Octane MPT tune they updated for long tubes. I have a 93 version too - just decided to load the 91 and see how it compares. After using the Track mode since the Sync 3 upgrade - when I still had shorty headers - I can tell you there is a good bit of difference when it comes to throttle response after the long tubes - especially when running track mode around town.

 

[ctandc72]

I'm running the 91 MPT tune - revised for the long tubes. Trying to find an opening to get with the guy who tuned it before for an update. The long tubes DEFINITELY added power. Conventional wisdom has the long tubes giving up some low end torque to the shorty headers - I don't see it. I definitely could be wrong and we'll see what the dyno says. The car pulls like a freight train from 3.5K to redline.

 

[zackmd1]

I'm running the 91 MPT tune - revised for the long tubes. Trying to find an opening to get with the guy who tuned it before for an update. The long tubes DEFINITELY added power. Conventional wisdom has the long tubes giving up some low end torque to the shorty headers - I don't see it. I definitely could be wrong and we'll see what the dyno says. The car pulls like a freight train from 3.5K to redline.

I can agree. When I went from LTs back to shorty headers on my 15 I most certainly noticed a performance difference in the top end with not much change in the low end. When I had the LTs they had not sorted out the tune yet so there was a lean spike under partial throttle in the 2.5-3k range. Is that present in your tune? Easiest way to tell is going up a slight hill in that rpm range and give it just a bit of gas to accelerate over the hill. For what it is worth, my track apps recorded 0-60 went up from a best of 4.9 with the LTs to a best of 5.4 with the shorty headers.

 

[ctandc72]

Well, I've been debating it for a while now - buying a lift for my shop that is. Problem is that my shop only has 9 foot ceilings and I really didn't want a permanent lift that I can't easily take down / move out of the way as needed. I've been reading reviews / installs on the Maxjax and the other night I hit up their website and they are having a sale on the standard package with a free rolling stool for $300 off the normal price. Just pulled the trigger.

https://www.maxjaxusa.com/dannmar-maxjax-standard-package.html

Even scored 12 months same as cash. It'll be here late next week. I'm really looking forward to not having to lay on my back anymore when working on the cars and trucks.

 

[ctandc72]

Picked this up today. Busy with other stuff but hope to start install next week.

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