HSM MSP Axle-Back Exhaust Review

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OK, OK, OK HERE YA GO (or "Here youse go", as they say here in Jersey...) the FIRST non-AGR#7 review of the HSM axle-back exhaust.

These results are based on an installation, one-block midnight test drive and a 12 mile commute to work, and may not be representative but are my first impressions:

Summary statement: scale 1-10, 10 being good:


9: Highly recommended if you don't mind it being a little louder than stock

1) Installation: A complete non-event. 27 minutes from when I began opening the box the install was completely done, including ALL prep, getting the tools (14mm and 9/16" sockets, monkey wrench, "never sieze" compound), ramping the car, and clean-up. If you can pick your nose and not get hurt, you can do this.

- get ramps out, back MSP onto ramps
- take MSP off of ramps because they slid on the damn garage floor
- brace ramp against tractor, put rubber mat under other ramp, retry, succeed
- silicone spray both exhaust hangers, undo 2 flange bolts and slip hangers off stock exhaust, remove (retain the gasket)
- "installation is the reverse of removal", use never-sieze on the new bolts Corey supplies (thanks Corey!)
- completely clean up, including put ramps away, wash hands (never-sieze is a bear to remove), and put stock exhaust into the box that Corey sent, hide on shelf so Wonderful Wife (WW) doesn't find out
- Drive around block at midnight, stay out of throttle so I don't wake the neighbors
- check clock when I return

Exhaust is louder than stock, deeper and throatier. I wouldn't say it's NON-intrusive, nor is it ricey (too deep a sound and no rasp). It has a bit of a resonance on deceleration around 2400 RPM, just happens to be one long downhill stretch that hits that RPM on my commute. Mellows out at 60MPH but is not as quiet as stock there either. No highway on my commute but I'll be on the highway later today and will report. Sounds VERY much like a Neon SRT4, only not *quite* as loud and has NO rasp to it. I have not heard it from outside. Sounds GREAT when you're in the throttle!

If you live in a quiet neighborhood or have neighbors with (ahem) good ears, this may not be for you. It's not bad, really, but it's not super quiet either (the stock exhaust is for that). Personally, I really LIKE the sound, but I'm fairly conservative when it comes to "sharing" my car habit.

Performance wise I haven't put a clock to it (may do that this weekend), but it really does seem to get into the boost more quickly and certainly feels faster. I tried several times with windows up and down to remove the extra noise from my "sensation of speed" and either way it really does feel a bit faster, more responsive (not night and day, but there if you're attuned to your car).

Workmanship: Looks good to my admittedly untrained eye. The tip looks EXACTLY like stock once installed (which is good - the stock tip looks great). The brackets are welded to the pipe itself and those welds look good. The chromed, rolled, slash cut tip is welded to the pipe with a decent sturdy bead - some spatter, but it's not visible from outside the car so who cares. The pipe is not mandrel bent, but the bends are fairly gradual so I expect minimal flow disruption. Pipe fit on the car perfectly, no modifications needed at all, and it even cleared my now-famous Hidden hitch trailer (bicycle rack, really) hitch. The pipes are aluminized steel - which will (given salty roads, etc) eventually rot out - but I'm putting the stocker on for winter so this is not a concern for me. I may remove the exhaust and high-temp-black paint it to help rotproof the thing.

Too early to tell on my long-term view. I'll probably keep it and reinstall the stocker if I need to visit someone on business or go to a job interview or something. If I tire of it, it's 27 minutes (can probably get it to 15 if I'm careful) to revert to stock. The HSM exhaust is good, makes better performance, and sounds good - a little louder than I'd think appropriate for taking a client out to lunch, but OK for taking a colleague on a spin! WW hasn't heard it yet and her opinion will count as well, so stay "tuned"!

ON a scale of 1-10 (10 being good), I give HSM:

Service/communication: 10 (nice job, Corey!)
Fit and Ease of installation: 10 (couldn't be easier or better)
Construction: 8 (would be a 10 if: cleaner tip weld, mandrel bent tubing)
Materials: 7-8 (would be 10 if stainless tubing, hardware - but that'd be costlier too)
Performance (dynamic): 8-9
Performance (sonic): (hear ya) 6-7 (this WILL vary by ear - many of the younger set or boy-racer crowd would give this a 10 or even complain it's not aggressive ENOUGH! I'm 41 and a father of 2 middle-schoolers - my ears are attuned to a different set of frequencies than most!)

VALUE: 10++ Corey's really put a quality piece together here for very little jing. WELL DONE!

Summary: 9 Highly recommended if you don't mind it being a little louder than stock

THANKS COREY! GREAT MOD, GREAT PRICE, GREAT SERVICE! (yippy) (2thumbs)
 
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Nice Review!

Now; have someone drive it, and listen from outside. Very nice! My wife thinks it sounds pretty cool.
 
In a neighborhood,,,,,,

...like mine where the speed limit is 20 mph; the sound is no issue at all. :D
 
Vicocola said:
so does it annoy u if u r on a road-trip that requires at least 1 hr drive?

Not at all, Vic! At least; I don't mind it. Today was the first day all year it was soooo hot that I drove with the Air on coming to work. It sounds good inside. It's present; but, I don't think annoying. You can still hear your stereo fine!
 
My question is this, I like hearing my turbo spool up & sometimes on the highway or anywhere for that matter, the stock exhaust note makes it hard to hear the turbo.
So with an even louder exhaust, Im thinking its going to make it even harder to hear my turbo. Is this the case?
 
RuggedMazda said:
My question is this, I like hearing my turbo spool up & sometimes on the highway or anywhere for that matter, the stock exhaust note makes it hard to hear the turbo.
So with an even louder exhaust, Im thinking its going to make it even harder to hear my turbo. Is this the case?

Hell no!! The turbo sounds sweet when it spools. My wife commented on it when I passed her on the highway yesterday. As sound goes, there are no negatives with this Axle-Back system. And yeah! the spooling is there. (thumb)

I do however have a K&N cone filter, and no stock air box.
 
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I think mine's a little louder than AGR#7's, or he's deafer.... don't get me wrong, it sounds good but is definitely "there", mellows out at highway speeds for sure but never is as mellow as stock.

If anything you can hear the turbo more. If you like hearing what's going on you'll like the HSM.

I like the sound, but you'd better not mind a little attention. Actualy the sound reminds me of an old Healey with the big 4... but more modern, techy, with the turbo when you get on it. A mellow 4 cylinder cound, not ricey but definitely not mistakable for a stock anything save for an SRT4... which sounds cool...

That said, I'll probably take mine off and save it for "fun" occasions, a *little* loud for making a professional entrance at the parking structure at work (bear in mind I manage a fairly large department at a German-owned Fortune 100 company - I'm "supposed" to drive something respectable... most of my colleagues drive big SUV's (pig-yuck) or Audis/Acuras and the like. I'm an oddball - and darned proud of it)
 
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