LS4 Performance - Potential 3" Exhaust Group Buy

Disclaimer::: this is just a feeler not an actual group buy...and I am not associated with the company at all just trying to make this happen for everyone:::

So Alabamaguy found a great deal on a full 2.5" or 3" mandrel bent, aluminumized or stainless setup on http://www.overkillengineeringmotorsports.com/wbody-exhaust1.html problem is it was for the older (91-98) W body cars.

I followed up with a few e-mails and pictures to the company president asking about fitment on the LS4 he said without "extensive modding" that system will not work. He went on to say that they will have something available in the next few months at similar prices and that if enough people are interested he can make it happen sooner...

So here I am looking for people who would possibly be interested in a 2.5" or 3" setup IF and only IF the price point at or below below those prices shown on the website. I believe it's $289.99 for the stainless with 3" and free shipping, and like $60 bucks less for aluminumized. I think it would have to drop below $250 for 3" to generate any interest especially since it's minus a resonator, mufflers and tips.

As of right now there are 3 people interested including myself, the owner said he was shooting for 10 or more. I asked specifically about price points and explained to him that if it wasn't competitive with the off-the-shelf Magnaflow system in terms of total cost people probably wouldn't be interested. It could be a while though before they establish a solid price.

So for now I'm just looking for names of those who may be interested if the price is right. Not sure what the rules on group buy stuff are so if a moderator wants to fill me in on that it would be appreciated. I'm just relaying info here.

If you are potentially interested add your name and 2.5"/3" and aluminumized vs. stainless preference so I can relay preference. I'll update as I get more information.

I'm in for the 3" stainless.

INITIAL TALLY

3"
Redlightrampage
Alabamaguy
20SS06
xdynasty725x
1Fast7
LS4:20
Hawkins04
Deimos
WhiteGXP313
1CL3ANSUP3RSPORT
GXP25
Mpgeagle
Supercatxr7

FM1R sold his car I believe but I will follow up.

06REDROCKET are you interested if he can only do full 3" or possibly full 2.5"?

TheJPGXP he may be able to do the single exit I'll find out soon.

If I missed anyone or someone on the list is no longer interested just shoot me a PM or just add a post and I'll update it.

3" to 2.5" Y split for use with mufflers that have a 2.5" offset input.

Im down for the group buy,"ifs it under $300".
Dom
3" into 2-1/2"

Single 3" exiting on the pass' side and I'm in.

I'm in for the 3" stainless!!

I didn't realize that these people are in Longwood, FL.

I'll take a drive tomorrow to see if they can take measurements off of my car.

EDIT: Aluminum versus Stainless Steel. Can anyone elaborate on the pros versus cons?

I know aluminum is cheaper, doesn't last as long because of it's rusty tendencies depending on your environment and would probably weigh less I would guess, heat would dissipate much quicker I think. Stainless has some different thermal properties, generally runs hotter and needs better design because of the heat issues, more durable and stronger though.

Aluminized just means regular steel is dipped in aluminum. This gives it better anti-corrosion properties. Stainless is the way to go. Especially at these prices. I am in BTW if it is the described price or lower.

-Mike

3" stainless, and if there good sounded exhausts

I may be interested in a 3" Stainless kit..

I'm in for 3" stainless.

Still waiting to hear back from them, nothing new to report. It could be a while esp since they don't have anything developed yet. Not sure how peculiar he is going to want to get with preferences, they may just say X amount for 3" or X amount for 2.5", don't know if they will want to make a bunch of peculiar systems if the group buy materializes, which I can understand right the point is to produce the same system in bulk to save everyone some money.

If I hear anything I'll throw it up here.

Ok so less than a minute after I posted I got this in my inbox:

"Looking good. I will let you know soon on a estimate price. Should be around the ball park you mentioned. As far as time frame goes, I think 2-3 months to get a system done is what we are looking at. If this is to long of a time frame let me know and I will see what I can do.

Mark"

Sounds hopeful! Hope we can make this happen!

I saw Mark today at around 4:30pm. Great guy.

He's going to wait on the guy who's doing the mandrel bending for him; the guy's in Miami. Once it's here, he'll test fit it on my car, make sure everything's perfect.

I'm thinking two different things here: One standard 3" from the catalytic converter two a 2.5" Y-pipe and one 3" from the catalytic converter to a 3" Y-pipe.

He wanted to know around how many people were interested. I told him twenty (20) or so.

So everyone who's in, "own" up so that redlightrampage can update the first post with a tally. :judge:

EDIT: Thanks to all of you who answered my question.

Another question: Would one exhaust fit all the LS4 vehicles or are there differences in the Y-pipes between the models? JP?

dual tips on grand prixs rather than the singles?

I saw Mark today at around 4:30pm. Great guy.

He's going to wait on the guy who's doing the mandrel bending for him; the guy's in Miami. Once it's here, he'll test fit it on my car, make sure everything's perfect.

I'm thinking two different things here: One standard 3" from the catalytic converter two a 2.5" Y-pipe and one 3" from the catalytic converter to a 3" Y-pipe.

He wanted to know around how many people were interested. I told him twenty (20) or so.

So everyone who's in, "own" up so that redlightrampage can update the first post with a tally. :judge:

EDIT: Thanks to all of you who answered my question.

Another question: Would one exhaust fit all the LS4 vehicles or are there differences in the Y-pipes between the models? JP?

Im down,but do we have a price yet?

I saw Mark today at around 4:30pm. Great guy.

He's going to wait on the guy who's doing the mandrel bending for him; the guy's in Miami. Once it's here, he'll test fit it on my car, make sure everything's perfect.

I'm thinking two different things here: One standard 3" from the catalytic converter two a 2.5" Y-pipe and one 3" from the catalytic converter to a 3" Y-pipe.

He wanted to know around how many people were interested. I told him twenty (20) or so.

So everyone who's in, "own" up so that redlightrampage can update the first post with a tally. :judge:

EDIT: Thanks to all of you who answered my question.

Another question: Would one exhaust fit all the LS4 vehicles or are there differences in the Y-pipes between the models? JP?

Well this is lining up way better than expected isn't it, lol. Frankly I was expecting it to kind of fall flat but shit we are off to the races on this thing.

Just comparing the 16727, 16726 Magnaflow systems everything is identical dimension wise except the Impala SS has dual split rear exists where the GXP has a quad split rear exist which isn't relevant here anyways. Sounds like the majority of people want 3" and a few want 3" to 2.5", but between those two groups I would say we cover the majority of people so I don't see anything wrong with that approach. Question is some people wanted aluminumized to save cost but if the stainless is cheap on the GB I don't see why they wouldn't switch? I'm guessing once development is done metal choice doesn't make a whole lot of difference so maybe they will accommodate.

Awesome that you stopped in there and lent them your car for demo, couldn't imagine a better situation to unfold on this, took all of the guess work right out of it, this could really pick up pace quick now...

Cool seeing the community coming together to make this happen.

Im down,but do we have a price yet?

No sir, still waiting. He said in the last e-mail that prices "should be around the ballpark you mentioned..", that was the 240-290 range shipped so I would expect it to fall in that area, hopefully on the low end of that because of all of the interest the thread is generating.

Might have to be a bit patient on this he's probably going to do some number crunching on the development costs to get a solid price point. I just hope it's cheaper than expected!

I'm 100% in for this, 3" stainless all the way back! Especially if that price is solid! Now.. Can someone find out if they ship to Canada?

I just went and priced myself a custom 3" stainless exhaust with aluminum flanges and was quoted well over $500 to build/install it, plus the cost of materials.. :(

Please make this happen and PLEASE SHIP TO CANADA!!!

dual tips on grand prixs rather than the singles?

No. This is from the catalytic converter to the mufflers.

So basically, a provide your own mufflers and tips affair.

Just comparing the 16727, 16726 Magnaflow systems everything is identical dimension wise except the Impala SS has dual split rear exists where the GXP has a quad split rear exist which isn't relevant here anyways.

So they are the same then? Even the Y section?

I don't think you can compare the Magnaflow kit because in the GXP kit, I believe that by changing everything out, they have altered the factory offset in/offset out muffler to a center in/center out.

Meh, maybe that other guy in Orlando with the SS could meet me up there one day.

No sir, still waiting. He said in the last e-mail that prices "should be around the ballpark you mentioned..", that was the 240-290 range shipped so I would expect it to fall in that area, hopefully on the low end of that because of all of the interest the thread is generating.

Might have to be a bit patient on this he's probably going to do some number crunching on the development costs to get a solid price point. I just hope it's cheaper than expected!

Well count me in then and put me on the list,3" stainless no res either 2-1/2" or 3" y pipe...

Stupid question, i know.. but are these a knock of magnaflows? they sound the same?

This be 3".

Put me down for full 3''

I'm 100% in for this, 3" stainless all the way back! Especially if that price is solid! Now.. Can someone find out if they ship to Canada?

I just went and priced myself a custom 3" stainless exhaust with aluminum flanges and was quoted well over $500 to build/install it, plus the cost of materials.. :(

Please make this happen and PLEASE SHIP TO CANADA!!!

Depending where you are in Canada, I would help you out if they can't ship there. I live in MI, and I am always on your side of the pond...

Stupid question, i know.. but are these a knock of magnaflows? they sound the same?

I wouldn't expect them to be a magnaflow knock off per say. No resonator is included or mufflers which has more impact on the sound anyways, so I would say sound preference would be ours to manipulate. I referred him to the magnaflow system for fitment and a cost comparison, not sure if he's going to mock them up similar or not, wouldn't have to reinvent the wheel if he did so I wouldn't be disappointed!

I can ask for a sound bite post development and maybe when GXP25 gets his car in there for fitment he will hang a whole system and give us something to listen to. If not I wouldn't be terribly disappointed.

Ehh first tally looks like 2 for 3" to 2.5", 9 for full 3", those of you who didn't give a preference just got thrown into 3" for now until I hear differently. Doesn't matter yet anyways as long as you are one or the other you are fine. Any special requests are tbd and didn't get counted, I can ask but doubtful he's going to want to make peculiar systems.

No. This is from the catalytic converter to the mufflers.

So basically, a provide your own mufflers and tips affair.



So they are the same then? Even the Y section?

I don't think you can compare the Magnaflow kit because in the GXP kit, I believe that by changing everything out, they have altered the factory offset in/offset out muffler to a center in/center out.

Meh, maybe that other guy in Orlando with the SS could meet me up there one day.

Yeah I'm not confident enough to really know, I've heard in the past that the only different was the tips. By looking at the systems side by side I seen no noticeable differences even in the Y pipe, same bend angles, lengths etc. Would be in their best interest to find an Impala SS to be sure, I wouldn't want to see assumptions being made here and have people unhappy.

Update:

1. "...Canada is $85 for shipping"

2. "I am working with my exhaust guy on this. He sees it being around 2-3 months for a system to be made. Is this acceptable?"

2-3 months lead time for this system to be developed, me personally I don't really mind as long as the prices are decent. He's looking for 10 "committed" people, what the committed means exactly he didn't clarify. Kind of hard to "guarantee" 10 people 3 months down the road when a firm price hasn't been established, although he's said it will "likely be in the ballpark you mentioned" which was under $300 shipped for 3" stainless, we should be getting a solid price soon. As it is now we have about 13 conditionally.


3. "We would make both 3 and 2.5".

You folks who wanted the 3" to 2.5" systems may have to choose between one or the other or nothing at all...I asked if he would accommodate a split system, I haven't heard anything definitive back yet.


So big question is here can you guys wait 2-3 months for a system if he gets a solid price within a reasonable timeframe? Personally I'm still in.

Yes, I could wait!!

BTW, why is everyone so gung-ho on getting 3" all the way back? It is just going to make your car louder but not really provide any better breathing than a 3" to 2.5" split. Hell, that arrangement would support 500+ horsepower, way more than most any MC, Impala, or GP that I know of....at least those cars with wrong wheel drive.

Yes, I could wait!!

BTW, why is everyone so gung-ho on getting 3" all the way back? It is just going to make your car louder but not really provide any better breathing than a 3" to 2.5" split. Hell, that arrangement would support 500+ horsepower, way more than most any MC, Impala, or GP that I know of....at least those cars with wrong wheel drive.

I'm down for 3".

Remember just because it can support "up to" doesn't mean it will do so efficiently. Like a restrictor plate will support up to xxx hp but if you take it off the motor will make much more. A larger exhaust is helpful with nitrous and turbo cars and even with a cam swap it will be helpful for those 6900-7000rpm pulls. Most major tuners recommend a full 3" system with these cars, especially after a cam swap. Will it loose a little on an otherwise stock car over a 2.5" system? Yes. The thermodynamics won't be "right" but you won't have the room to upgrade like you would with a 3" kit.

This is just IMO.

Its official like a referee whistle, full 3" stainless for me!

I'm still in!

So ya'll know the system is in development, there may not be any updates for a while but Mark has told me he is working on it daily. So keep it in the back of your brain for a while and if I hear anything new I will pass it along!

Bump for anyone else interested. Mark says he's still pushing development. Going to bump every 3 weeks so new ppl have an opportunity to get on board and to see if anyone drops off.

Selling the car I think, so I maybe out.. Found a clean used G8 GXP that has my name on it.

Nice choice love those cars! For everyone else Mark said to expect "something" by the end of the week when asked about prices and ETA on the systems. So expect to hear more soon.

Nice choice love those cars! For everyone else Mark said to expect "something" by the end of the week when asked about prices and ETA on the systems. So expect to hear more soon.

Yeah, if I don't end up getting that car then I will probably just keep the GXP I have now. I need the 4 door or else I would have a vette or F body..

Cts-v?

Update from Mark this morning:

"Just talked to my exhaust guy. He is finishing up two big projects in the next few weeks. Once he is done he can start the process of getting me a quote and a test system out to a customer. So we should be seeing something soon"

GXP25: You still going to do the testing?

Full 3", stainless.

Yeah whenever he emails me.

im down lfor stainless 3 inch let me know

im in for a 3" stainless....anyway i would be able to keep the stock tips?

It doesn't come with mufflers so yeah if you wanted to make it work you could. I'd imagine you lose quite a bit of inner diameter on those on the way out though? Not sure I'd want that tappered at the end like that but thats just me.

It doesn't come with mufflers so yeah if you wanted to make it work you could. I'd imagine you lose quite a bit of inner diameter on those on the way out though? Not sure I'd want that tappered at the end like that but thats just me.

Slap a 3" cutout on it before the mufflers and call it a day. That way you keep the "stock" look, but have all the sound and performance of 3" exhaust.

Anymore updates on this?

Nope. I send him emails every 2 weeks. I sent one 3 days ago and he said he doesn't have anything new to report.

Good news on this front, got an e-mail last night from Mark and it looks like he is about 2 weeks away from having a test system ready! Cost of the system still hasn't been divulged but like he said before it should be under $300 shipped.

For now I'd like to know if anyone who already put their name up here isn't interested anymore??? I need to get him a solid tally tomorrow so if you changed your mind let me know, also if you want to jump on board now is the time. PLEASE re-read all of my posts before you make assumptions about what you are getting out of this.

Edit your first post with the list of names with numbers next to them. Also stipulate that it'll be 3" all the way.

"We would make both 3 and 2.5" . I will ask again just to be sure but it sounds like the split sized system people would have to choose one or the other. I'll update the first post though.

I updated the tally on the first post. Looks like most people moved to the 3" anyways so I guess it's all good. I need to hear back from FM1R and 06REDROCKET. I believe FM1R sold his car and 06REDROCKET needs to pick an exhaust size. Until I hear otherwise it's full 3" or full 2.5", no split systems.

For now I'd like to know if anyone who already put their name up here isn't interested anymore??? I need to get him a solid tally tomorrow so if you changed your mind let me know, also if you want to jump on board now is the time. PLEASE re-read all of my posts before you make assumptions about what you are getting out of this.

I'm interested in how the project goes--especially the dyno results--but I will not be making a purchase at this time.

Wes

I'm interested in how the project goes--especially the dyno results--but I will not be making a purchase at this time.

Ok, you aren't on the tally... unless you have another user name.

Ok, you aren't on the tally... unless you have another user name.

Yeah, no, I'm not on the tally, but I have been following the thread since it started.

I have a huge amount of respect and appreciation for folks like you guys who are innovating and coming up with new, improved parts for our cars.

So, I just want to say thank you to you and AlabamaGuy for your involvement with this.

Wes

So here is the deal, they want to do development and testing using Aluminized, 2.5", systems before they start producing "true" 3" stainless systems. Most of you want stainless steel, 3" but that isn't going to happen until they can work through any issues without wasting expensive material, understandable.

Here is the catch, they need a few people to test systems, read below, ignore the Grand Prix years, they are generalizing LS4s to all 3rd gen W-body exhausts not sure if that is even the right thing to do but I really don't care how they handle those other cars as long as we can get LS4s to hang systems on for fitment.

"We are looking for these people:

1. A Grand Prix owner from 04-08 (LS4 preferred) to test fit a 2.5 inch tubing kit.
2. A Monte Carlo owner from 06-07 (LS4 preferred) to test fit a 2.5 inch tubing kit.


We can offer an Aluminized System for $140 shipped to these owners. They would be pay $195.00 up front and receive a $55.00 refund once we receive feedback and pictures of the install."

Not sure why they didn't contact GXP25 to test fit or measure the GXP, that still could be an option instead of selling 2.5" to people who are in on a 3", stainless GB.

I'm assuming he is still willing to do the testing for the GXP, so we would probably need an LS4 Monte owner who either lives in the Orlando area or would be interested in buying a 2.5", Aluminized kit and helping with development.

If anyone for that matter is interested in the $140 2.5" Aluminized systems and can help with development please shoot me a PM with your contact info and I can relay it on to Mark.

I did ask about potentially paying for the $140 Aluminized system to return it after fitment is verified for credit toward a 3" stainless, haven't heard back yet as to that approach.

Not really what I was expecting to hear but it looks like we are still moving forward on this at least.

So there has been a bit of a change, apparently they resolved the fitment issues and won't be needing to test 2.5", Aluminized systems first. Mark said the 3" systems should be rolling out the door in 2-3 weeks...below is the verbatim e-mail.

"For the payments, We will go ahead and set-up a GXP section on the website. From there I will include all the details. We dont take orders over the phone at all. People will be able to use CC or Paypal.

I am shooting for 2-3 weeks to start shipping, if everything goes as planned.

For the single exit guy I am still waiting to hear back

For the price, I will let you know very soon."

Lot of thanks go out to GXP25 for stopping by and helping Mark work through fitment issues. We would probably be weeks behind if he didn't happen to be in the area and willing to spend some time there.

If you haven't checked the 1st post please do so now and make sure that I did the tally right.

If you have particular questions please let me know and I can relay them on to Mark.

So there has been a bit of a change, apparently they resolved the fitment issues and won't be needing to test 2.5", Aluminized systems first. Mark said the 3" systems should be rolling out the door in 2-3 weeks...below is the verbatim e-mail.

"For the payments, We will go ahead and set-up a GXP section on the website. From there I will include all the details. We dont take orders over the phone at all. People will be able to use CC or Paypal.

I am shooting for 2-3 weeks to start shipping, if everything goes as planned.

For the single exit guy I am still waiting to hear back

For the price, I will let you know very soon."

Lot of thanks go out to GXP25 for stopping by and helping Mark work through fitment issues. We would probably be weeks behind if he didn't happen to be in the area and willing to spend some time there.

If you haven't checked the 1st post please do so now and make sure that I did the tally right.

If you have particular questions please let me know and I can relay them on to Mark.

Lol really? I didn't do a thing. I've only been to his shop once, heh.

I was offered the chance to get the kit and test it out due to our schedules not working out (I'm not free weekends).

LOL I know but he said he was going to get ahold of you so maybe it was just a premoniton...thanks in advance?

Updates:

"Test system is shipping to me (Mark) today. Once fitted, it will take a few days to get systems pumped out.

We are looking at $525 for a Stainless Steel 3" dual system, $450 for a Aluminized 3" dual system. Thats complete muffs and all.

If you wanted just piping it would be much cheaper. "

For JPGXP wanting the single exit:

"It will be $35 more because of a jig change."

To get a GB discount:

"For that pricing I would need 10 Orders, does not matter options. I will get you a piping kit price soon. "

Hard to tell if we have 10 solid when a 3" tubing setup hasn't been quoted shipped. If anyone doesn't forsee having the money available for the assumed price range in the next 3 weeks please let me know.

Shipping:

"Also Shipping is $45 US, $100 Canada"

This was full system shipping. I am still waiting on just the 3" stainless tubing kit price and the shipping for just that which is what we all were on this for.

I'm also waiting on whether or not a resonator will be included in the full-system if people wanted to go that route.

Still not sure about the total cost of the system that everyone has been expecting: 3" stainless, NO reso and NO mufflers. in case you missed it somehow. I had no idea he was going to do full-systems but that is a decent price for full, true 3" SS systems, no idea how they are going to sound I'm sure some people would want to hear that.

Double check the list in the first post...let me know if there are any changes to your plans.

More to follow..

Good work on getting a 3" kit going. I paid 1000 for my custom setup.

is it on yet!?!?!?! sorry cant wait to hear it

whats the size of the magnaflow kit?

^^2.5" IIRC.


What kind of mufflers are they putting on these?

Not sure about when a sound byte will be available, I'm not doing the testing and I guess he's having some issues lining up schedules with the guy in the area. Should hear more early next week I would guess.

If this kit does not come with mufflers wouldn't we be better off just buying a magnaflow system? What real benefits would we get between a 2.5" or 3" system?

If this kit does not come with mufflers wouldn't we be better off just buying a magnaflow system? What real benefits would we get between a 2.5" or 3" system?

Not if you want a 3" setup,if you want 2-1/2" yes it would be better to by the magnaflow kit

Not if you want a 3" setup,if you want 2-1/2" yes it would be better to by the magnaflow kit

right but is there any real benefit to get the 3"? Im only asking this because this 3" kit will end up costing around $750 with 2 new mufflers and new tips

right but is there any real benefit to get the 3"? Im only asking this because this 3" kit will end up costing around $750 with 2 new mufflers and new tips

Someone touched on this already I believe.

The group buy is under the assumption the system would be piping only, no reso, no mufflers, SOUTH of $300 shipped. Unless you plan on spending $450 on mufflers and tips you can get out with a custom exhaust for far less than that. Which those on the GB want something they can DIY so that is the benefit.

From my understanding he also developed or is developing an entire system that he will continue to sell off-the-shelf, to include mufflers:

"We are looking at $525 for a SS 3" dual system, $450 for a ALU 3" dual system. Thats complete muffs and all. [B]If you wanted just piping it would be much cheaper. "

I had no idea he was developing an entire system based on the GB interest, which is great for the LS4 community. There are enough headers + magnaflow combos out there.



================================================== ===
I asked what "Muffs and all" means and I haven't heard back.

I also asked about the kind of mufflers or sound of the system and I haven't heard back.

This is being daisy chained from the forum to me, to Mark to his "exhaust" guy and back and it hasn't been the quickest process.

So be patient I'm sure we will here more this coming week.

I really hate to say this especially after all of the effort that went into trying to make this work for everyone..this GB is currently DEAD in the water and I don't really expect any of it to pan out at this point. This guy has been giving me/us the run-around now since August and I'm done playing the liaison role here. None of this is materializing and has in the end been a complete waste of time.

This Mark fellow has been very unwilling to use his time/money/energy to make any part of this work and from the complete lack of e-mail communication and actual follow through lately, I do not expect anything to come of this. He actually won't spend ANY time or money of his own to hang/fit a system himself. All 3 hours worth right...

In-fact he won't even cover the return shipping to send it to me so I can fit it myself, do a sound byte and even dyno it and return it...all which I have been volunteering for free if he can just cover the return shipping or let me keep the test system with a discount.

Really disappointed I couldn't bring this to the forum. I'm sure we can find an actual shop not the middle man who can make something happen for everyone.

If he does end up producing stuff I sure as shit won't be buying it just based on my opinion of him.

Sorry this didnt work out the way we wanted it.