When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I am the new owner of a '99 Firehawk. As it stands now, the car has speed engineering headers into a "custom" x-pipe with turn downs on it. I like my hearing so I am trying to remedy this situation.
What I have:
Speed engineering headers
OEM SLP dual/dual muffler
I do not have the OEM intermediate pipe since someone thought it was easier to cut it out rather than disassemble.
What I am trying to accomplish is keeping the SLP dual/duals with the headers. It doesn't seem like this would be difficult but everywhere I look I am getting different answers. I know I need a Y pipe. Either the Texas Speed or Speed Engineering part should get me that far.
Is there an intermediate pipe anywhere on the planet that will get me from the Y to the muffler? Even finding an OEM SLP unit seems to be impossible.
Any help is much appreciated.
...and as a bonus, I can't spell. FireHAWK. Not hack. 1 of those days.
Last edited by Botch316; Oct 18, 2017 at 04:30 PM.
Dyno max used to make a 3 inch I pipe for over the axle to the catback, not sure if they still do.
I took my 91 RS to the local muffler shop and had them custom make a 3 inch I pipe over the axle for the SLP Dual / Dual. It matched up perfectly. A good muffler shop should also be able to make a good Y pipe with a 3 inch flow master collector. I think that's your best bet.
My old Mufflex Y-pipe 3 inch to 4 inch sound good with the SLP Dual /Dual. The bad part is the Mufflex doesn't fit very well.
Thanks. I saw the 3" intermediates out there. Custom at a shop is where I figured I'd land in the end. Was hoping there was an easy option out there somewhere.
what about buying the Hooker Blackheart true dual kit and adapting it to your headers, not a big job.
Getting a full aftermarket setup on it wouldn't be too difficult at all. There are quite a few out there that could bolt right up. I was trying to get the original SLP dual/dual on it simply out of principle.
The guy at SLP that I spoke with was about as useful as a football bat.
You can buy mandrel bends almost anywhere. Look under the car and eyeball roughly what degree bends your going to need to go up and over the axle order them then go to a exhaust shop and have them run the straight section and build it. If they grind the welds it'll be hard to tell it was pieced together. I built my own 4" system that way.
I don't think that Dynomax setup will easily work for this situation. I am fairly certain that the dual/dual I took off my car was 2.75" instead of 3" so it would have to be necked down some at the muffler. Most end up cutting these off because its damn near impossible to get the intermediate pipe out of the muffler. That's what I had to do on my car earlier this year when I swapped to my TSP catback.
The best thing to do is to look around online and find a complete catback and use what you need. They typically go for around $150 or less and maybe you can find one that was taken apart the right way. There's also a facebook group for Firehawk owners and is where I ended up selling mine at. They might be able to track you down what you need as well.
I am the new owner of a '99 Firehawk. As it stands now, the car has speed engineering headers into a "custom" x-pipe with turn downs on it. I like my hearing so I am trying to remedy this situation.
What I have:
Speed engineering headers
OEM SLP dual/dual muffler
I do not have the OEM intermediate pipe since someone thought it was easier to cut it out rather than disassemble.
What I am trying to accomplish is keeping the SLP dual/duals with the headers. It doesn't seem like this would be difficult but everywhere I look I am getting different answers. I know I need a Y pipe. Either the Texas Speed or Speed Engineering part should get me that far.
Is there an intermediate pipe anywhere on the planet that will get me from the Y to the muffler? Even finding an OEM SLP unit seems to be impossible.
Any help is much appreciated.
...and as a bonus, I can't spell. FireHAWK. Not hack. 1 of those days.
Do you care if the I pipe and the pipe over the axle is stainless? If not, then a walker 53061 and 54064 with the speed engineering Y pipe is all you need. I have that setup with my SLP center mount exhaust but I don't have an OEM muffler, but the 2nd most quiet option which is a Dynomax #17227. I got the walker stuff from summit.
Speed engineering headers and Y pipe. I have a magnaflow 14419 resonator in the I pipe also. Even with all this, it's no where near as quiet as a stock exhaust. I suggest putting an electric cutout just after the Y merge. This is what I plan to do. I tried dual cutouts in the speed engineering Y pipe but not enough ground clearance.
Ditch the clamps that come with the Y and use Walker 33272 exhaust clamps.
Thanks for all of the advice. It is much appreciated. I have the 2 Dynomax/Walker intermediate pipes in the garage now. They do fit the OEM muffler inlet (both are 3"). I am waiting on a Texas Speed catted Y to be delivered. Speed Engineering says that their Y works with TS headers so logic (scary) would tell me that the TS Y would in turn work with the Speed Engineering headers. I guess we'll see. I decided to go with the TS because they offer cats to try to cut down on the smell a bit (aftermarket cam as well). If everything does what the manufacturers claim it will do, I should be pretty close. If not, I'll either fab something myself if it is just some bending or cry uncle and have someone else do it if it is more complicated than that.
Originally Posted by 1bdbrd
I don't think that Dynomax setup will easily work for this situation. I am fairly certain that the dual/dual I took off my car was 2.75" instead of 3" so it would have to be necked down some at the muffler. Most end up cutting these off because its damn near impossible to get the intermediate pipe out of the muffler. That's what I had to do on my car earlier this year when I swapped to my TSP catback.
The best thing to do is to look around online and find a complete catback and use what you need. They typically go for around $150 or less and maybe you can find one that was taken apart the right way. There's also a facebook group for Firehawk owners and is where I ended up selling mine at. They might be able to track you down what you need as well.
The Dual/Dual that came off of mine is definitely a 3". I've heard that they varied from year to year. Of course that was something I read on a forum so take it for what it's worth.
Thanks for the heads up on the FB group. I don't use the bookface but I may sign up simply to join that one. If I can find an OEM intermediate I would like to do it, even if it is only to keep on hand to bring it back to OEM if I decide to do that some day.
I've been out of the F-body world since about 2000. Good to be back!
Last edited by Botch316; Oct 21, 2017 at 10:57 AM.
An update for anybody who may try this in the future. Walker/Dynomax has what must be the dumbest designers on the planet. The 54064 is necked down on the engine side so it is a line to line fit with the Y pipe. Not a huge deal, put it on an expander and it becomes the slip fit that it should be. However, the tail end is even worse. These idiots actually have it expanded to be an OD slip fit. The engine side of the 53061 that it is supposed to connect to? Yep, it's expanded to be an OD slip just like the pipe it is supposed to connect to. I checked a couple of other reviews and apparently this isn't just a 1 time oops. They are all like that. Idiots.
In short, they don't actually fit together the way they should.
I ended up using the 53061 (minus about an inch off of the discharge end because it was too long and offset the muffler to the driver's side) and then making a 3" mid pipe to connect the rest of the way forward. I did have to slightly "clearance" a couple of spots to get the Texas-Speed Y away from the bottom of the car which I wasn't too happy about. Maybe I'm spoiled with my previous Corsa/Corvette systems but it really doesn't seem like it should be all that difficult to make an exhaust that doesn't need a f'n hammer to be installed.
I was stubborn and got it done... despite the stupidity of Walker.
Final setup:
Speed Engineering longtubes
Texas-Speed catted Y pipe
"Custom" 3" mid-pipe
Walker 53061
OEM SLP Dual/Dual
Sounds pretty damn mean without being obnoxious.
On a related note, I'd still like to find an original SLP dual/dual setup with the intermediate pipe still in 1 piece. If anybody has one, I'd be interested in it.
Glad it worked out. These things never go together right out of the box. What kind of ground clearance do you have with the TSP Y? Can you measure the lowest point of the exhaust on the Y pipe to the ground, then measure from the ground to the top of the wheel well (typical this measurement is 27-28.5 inches) to get an idea of how ride height variance will impact ground clearance with that setup.
Thanks for the follow up. I happy you got the exhaust sorted out.
Sorry to hear the Walker had issues.
I'm glad it wasn't as bad as the Mufflex Y-pipe my 99TA used to have. It had to be cut apart, repositioned and welded back together to get it to fit. Likewise, the Mufflex set up for early C3 Vette's on my 72 Vette Nad to be cut, repositioned and welded back together to get it to fit.
After those two experiences, the white RS went to the local muffler shop and they built a custom 3 inch I pipe and over the axle for the SLP Dual /Dual on the RS. It fits very well no issues and saved a lot of head ache.
3.75" clearance with a front wheel well height of 26.25" I have the car down pretty low at the moment but not "slammed"
That is tucked up absolutely as far as possible. The lowest part are the individual Y sections before the merge. In the picture you can see that there should be room to raise it farther at the low point but any farther and it hits farther upstream (unless you get out the BFH and bend some metal).
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.
HELP! Firehak Exhaust w/headers 
