If you haven't bought it already then I'd buy it in a hurry. That's all out of production now.

Same goes for any long tube header for that matter. Buy it now before it's all obsolete. EPA is all over these exhaust companies.

 

Yeah, thats right. I remember now. I didn't want to drill on a new unit and I had long lost the original bolts. No big deal.

 

Everything critical shows in stock on Holley's website. I need the header back soon for mock up/fuel cell fab work, but headers were going to wait. If there is a non-zero risk I will buy the headers at the same time in a couple weeks. Along with the TQ arm and panhard.

As a side note, for a bagged car, why would it be important to lower the panhard bar? I plan to drive at or close to stock ride height. Does that make all these additional pieces being discussed non-critical?

 

Aftermarket parts are stronger with a lot less flex. Now does that matter to you? Meh, for cruising, probably not. ....then of course, the adjustability is important for significant ride height changes. ....but if you think you'll be driving at stock ride height, then.....yeah, probably not as important. ...and that of course is assuming the lengths and angles were right from the factory, which many were not, or at least not ideal.

 

Quick update. I decided to just get Founders TQ arm, Panhard rod and track bar. I like the lower prices, of course, but I also didn't want to spend a bunch on parts that I may be banging around and building around as I try to get this car as low as I can on bags. Some parts may be bumped and scraped.

As an annoying side note, the Blackheart stainless long tube headers that Holley made to go along with their true dual setup have been discontinued. They are nowhere to be found.
I contacted 3 different resellers to see if there was a mistake or if there is any in stock they could find. No dice.

Starting to plan out my plan B. The full stainless pipes are still available, and so is the double hump cross member. Just need to find a LT headers alternative.
Hawks sells some made for them by Stainless Works. Need to learn if the collectors exit near the Holley x-member humps and would bolt up to the Holley dual setup.
I will make a new thread in the exhaust section for that discussion.

 

Yeah, that was an abrupt end to that product line due to some new California EPA laws that trickled through their product line. Speed Engineer, Hawks, and Kooks makes a header for these cars and most should be close enough to the dual exhaust that any shop should easily be able to make them work with a little fab work. In fact, I believe I've read a thread where the eBay headers mounted up perfectly.

 

Nice to know someone else thinks there are other options that are close. I am in no rush so I am waiting to see if Hawks customer service will get back to me about their headers being able to line up with the Holley trans x-member.

If it was mild steel I could weld it with my little welder, but I can't do stainless with my baby flux core.
Even if I am rig it up to get it to a shop for a custom transition, then that is fine. Also a ways a way down the road.
I really just need to keep my eye on the prize and finish from the back seats back first, under and inside. Once I have those Founders parts, exhaust mocked up, and fuel cell cage fabricated, then I can get a strong hard look at the wheel tubs and decide on a tire/rim combo.

I'll keep looking for someone that had stock of the Holley header when it got discontinued.

 

Here's a list of exhaust options to get you started on the hunt, https://www.thirdgen.org/forums/ltx-...-ls-swaps.html

 

Thanks for the link to all that information.

Think the Hawks long tubes would line up with the Holley Blackheart duals and x-member?

 

Holley trans cross-member was made for their 2.5" exhaust pipes and is a bit of a tight squeeze at the tail of the trans. Hawks uses 3" Y-pipes and their trans cross-member is much more spacious for exhaust routing. I tried the Hawks 2" primaries header & exhaust kit (3" Y-pipes into 3.5" single) with Holley cross-member and it was a total no-go. That system is different from the others though so maybe not representative of the fitment with the other Hawks exhaust systems.

I have a memory that somebody has used Speed Engineering headers with Holley dual exhaust but I don't have the story to link and not even sure that's right information either. Honestly, a good single exhaust system will be fine and have less drone cruising. Dual exhaust kind of sucks to live with in our cars. Although you have much more space for larger mufflers since you raised the fuel tank, so maybe you could work out larger mufflers and better sound management than most people.

 

Me too. I've been trying to find it. At the end of the day none of these exhaust should be expected to "bolt right in". I'd buy some 409 or 304 (whichever metal you selected) tube from amazon and have it handy for your exhaust guy.

 

Honestly, that 3.5" Hawks system is one of the best sounding exhaust systems ever to grace an F-body. Owner of my local speed shop said it was in the top 2 favorite sounding exhaust of any car that's been through his shop. I know several people that changed over to Stainless Works mufflers after hearing my car.

I'm not going to lie though, it's loud. But it's pretty easy on the ears below 1800 rpm (especially below 1600 rpm) where a nice driving car can cruise. And compression is loud and I'm at 11.8 so I'd expect maybe an LS3 crate engine might not be as loud with that same exhaust. Actually, I think @TEDSgrad has that same exhaust with stock LS3 and can maybe comment on that.

 

You have the 4" version correct? What RWHP are you pushing through it with the LS7?

 

3.5" version. I think it was around 575 RWHP with tires spinning between 4K - 7K rpm. Never did get a good run/number off the dyno. I'm probably leaving a lot on the table but it's perfectly fine for a stock-ish LS3.

 

Ingnore. He beat me to the punch with an edit. Agree about a stock LS3.

 

More Duration, more RPM and there definitely more Power.

 

The engine itself can clear 600 RWHP any day of the week. As it sits in my car I don't think it can, not enough exhaust. But these are just guesses, I have no good data. Haven't even got a trap speed with this engine. What's really amazing though is how good it drives at that power level. Tony Mamo is one of the kings when it comes to porting heads for real street cars.

I've got an idea brewing that I haven't shared yet that involves PWM active exhaust valves..... But I haven't done anything yet and who knows if I ever will (like a lot of my ideas). I could explain it to somebody else if they have time & interest to take a crack at it. Some testing will be needed to figure out how to control the valves.

 

I'm an edit ninja, man!

 

You know it! It was only just a couple years ago that I even realized the importance of RPM's to going fast. And I think most people are in my camp, not understanding that concept. It's not a conversation that's well explained on the forums.

My results were kind of pathetic compared to what the Corvette guys are doing. Everything is harder with an F-body. And the "fixes" can push the car over that fine line that make it more miserable than fun on that drive to work in the morning.

 

Here's that thread about the Speed Engineering headers and Hooker Blackheart.
https://www.thirdgen.org/forums/ltx-...rs-hooker.html

 

 

With the new Clean Air laws that passed, is it legal to install an LS3, long tubes and no cats?
Where I live in RI, if your car is older than 25 years you don't have to pass smog anymore. My car is 32 years old now.
Aren't I fine?

I was about to buy the Hawks stainless headers and Blackheart stainless duals when I remembered the thread that talked about the Speed Engineering headers. Those are almost scary cheap. Like $300 vs the Hawks that are over a grand. Both claim 3" collectors and 304 SS constructions.

 

Yes you should be fine. Also, the speed engineering stuff is super cheap, but is actually decent. Real 304ss too.

 

In your opinion is it worth spending the extra $ on the Hawks units?
The polished stainless looks sorta tacky to me. But if fitment is spot on with a Holley x-member and duals, then I can look past that.

Does anyone know if the Blackheart system has 3" inlets? I believe it does. Just wanted to confirm.

 

Yes and no. True dual exhaust are super cool, help with power and all that. However, they are expensive, heavy and very loud. I can live with loud, it is the cruising drone that gets me. If I had to do it all over again, I would have probably gone with a 4" mufflex and called it a day. I have a unicorn for an exhaust, is amazingly built, leaves no power on the table but doesn't sound all that great and drones the bones right out of you. I am sure a different muffler will help me and I am not giving up on it yet. But I like QWK's idea of a single 3.5" system for your application.

 

Thanks for the input and your experience!

I have run a single 4" Mufflex back in the day with a 383 stroker and an F1 blower. That build was literally insane, haha. At least for me.
I want to specifically build the car this time to NOT be insane.

I am down with a single, I am not married to duals. I do NEED to have no muffler in the stock muffler location. That limits me to either full custom or duals (from what I can find).

My fuel cell will live almost exactly where the stock muffler is. The duals put the mufflers off to the sides. Exactly what I need for this build.
I hear the concern about the drone. Fingers crossed my stock LS3 will be tame and not drone too much.

 

Almost all exhaust systems place muffler in stock location. Its sounding like duals fit your needs better with the mufflers tucked off to the sides. 3" pipes are MUCH MORE LOUD than 2.5" pipe. The Holley Blackheart duals likely would be the quietest of the dual systems (and the only one tailor made to a 3rd gen chassis).

 

Went ahead and ordered everything today.
Hawks stainless LS swap 1-3/4" long tubes.
Blackheart 304 stainless duals, Holley trans x-member, motor mounts, etc...

Happy those decisions are behind me. I am sure I will get it to all work out.

 

You'll be happy. My nitpicking on my own setup is semantics.

 

x2 I think you will be very happy with that setup. I've used Stainless Works and Speed Engineering LS swap headers. I actually have a set of each hanging on my garage wall right now for use on future projects. The quality and fitment of the Stainless works headers is fantastic. Speed engineering quality of materials and construction is not as nice but fitment is just as good or better...hard to beat the value. One advantage of cheap headers, you don't cringe every time you hear something scrape the exhaust lol.

 

I definitely thought about the price and how I will most likely being messing most of these parts up at least a bit on a custom build like this.
Trial fitting, testing air bag range of motion, etc... Good chance parts will not stay mint for long, but that's OK.

I Just really want to start off with quality stuff. I have built this car up several times in my 20's with cheap as possible stuff. I want to put those days behind me.

 

I have just been overwhelmed these last 2 Years...
(I only then found out that exhaust Products were available that actually fit our Cars)
And now am so damn aggravated that I missed pretty much the entire Window of availability for all these exhaust products.

I was going "Pie Cut Crazy" for far too many years producing custom Exhaust for these Cars.
And Now it looks like I will have to do it again!


Hopefully I can scavenge some of these Parts (for my own Car) before everything disappears!

 

GDMFs!

 

In the future evening news will be reporting statistics on the number of long tube headers that cross the southern border every year.

 

Quick question: Here is the engine and trans package I plan to use for this build.
https://paceperformance.com/i-159087...n-package.html

I am guessing that since it is fairly mild a long tube with 1-3/4" primaries and 3" collectors will be fine. Going to be running the 2.5" Blackheart duals setup.
No need to just up on primary sizing correct? Figured I would ask, just to be safe.

 

Those headers will work okay but 1-7/8" primaries is more typical. Same story with the dual 2.5" exhaust, it will work okay but something larger would work better. But honestly, the decibels difference between 2.5" and 3" pipe is huge, and the few Hp difference probably isn't worth that tradeoff IMO. Loud and rowdy is fun at first but gets old after a few years.

And duals don't give the best ground clearance either so keep that in mind. One pipe has a place to tuck in the span behind trans to axle, the other pipe doesn't really tuck and eats up ground clearance. Keeping to smaller 2.5" pipe eases the packaging problems with duals.

 

Noted the ground clearance issue with duals.

My project is sorta unique in the sense that I shaved my fuel door, side markers, locks and antenna. Will soon be shaving my door handles.
Since I don't have a fuel door, I need to fill up thru the trunk floor, directly into a tank. This idea lended itself to a fuel cell in that location, so I modified the floor to accommodate one.
To that end a stock gas tank doesn't make sense and since cells are a big box I needed to replace the location of the muffler.

The only off the shelf stainless system that did that is the Holley Blackheart duals.

As for the 1-3/4" vs the 1-7/8" primaries, since I am not going for max power but more going for drivability and low end TQ, I figured the smaller pipes would be better. Especially since these are already LTs.

Does that logic check out?

 

Neither header will result in poor drivability. You really can't screw this up, the engine is going to drive nice either way.

Just as a side note though, low RPM torque is way over rated - that's what gears are for. Higher RPM torque is what makes a car fly. What makes an engine sucky to drive at low rpm is when the driving manners become poor - bucking & surging, lifeless throttle response. This is what kills the enjoyment of driving the car. It's due to a lack of port velocity in the heads. You're not at risk of that problem with your engine combo, unless you have the ASA cam (which you don't).

 

Thanks for the insight. I figured with all air lines and trying to tuck wires, fuel lines and brake lines I might as well go with a slightly smaller primary.
The LS3 will be either the Pace unit or a Blueprint unit already broken in on the dyno by them. Looking forward to this project slowly creeping forward.

My Moser 12 bolt has 4.11s in it and when I had a carb'ed 383 / T56 combo in it, it was fun to drive. Think that rear end will work out well here too.

And since I don't think this will ever be a super go fast car, I will be happy with the smaller pipes. Would rather have it be quieter. I can scare myself plenty with my C7 or motorcycle!

 

While I agree with you to a decent extent (Torque production in some instances, at certain Engine speeds, can be a bit over-rated) especially on the street where there is little to no traction anyway...

However, with Slicks on a prepared surface (absolute traction)... Torque production can not be even slightly over-rated.
Yes there will be Torque Multiplication from the Torque-Converter (for an instant), the Transmission Gearing, and the Differential Gearing...

BUT with some real/ serious Torque Production... CAN I SAY MASSIVE WHEEL-STAND! ...Nothing compares!!!

Top Fuel Dragsters and Funny-Cars are literally pulling just over Six G's under acceleration.
Believe it or not, the acceleration portion of the race is not the most violent part.

Its the release of the Parachute...
Now there is a Six G force in the opposite direction...

THAT'S A 12 G CHANGE IN 0.001 SECOND!

 

It does sound great! Neighbor 8 houses down said I nailed the exhaust note! Cool when a neighbor likes the sound!
Actually, I have a stock LS2 tuned. The Hawk's LS7/SW is a good system. Not the fit like a glove advertised system. Any "system' will require fitment - be forewarned. It is important to have realistic expectations. Mid-pipe required additional tweeks/expense. V-band clamps are the way to go.
Kooks is a good option. That pesky mid-pipe is going to need customization at this size no matter what the salesman/woman says - plan for it.
IMO, LS motors/heads respond well to exhaust side improvements. Don't be shy, buy well. Once past the pain, you will be satisfied/not have to repurchase.

It's all a work in progress!