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Ok.

I recently posted http://www.mazda3forums.com/index.php?topic=71663.0

[quote author=c0ldFuzion link=topic=71663.msg1260851#msg1260851 date=1173592622]
Got my Race Pipe in and installed it today. However, I have a question.

On launching the car, I noticed that when I shift from 1st to 2nd that I hear a loud flex at the bottom of the car. If I dont shift super fast, I dont hear anything, but when I shift aggressive I definitely hear a loud flex at the bottom of the car. :shock:

I checked underneath, everything is still bolted correctly and everything.

The only mods I have are the MS CAI and this race pipe. I know its nothing to do with the CAI (since I had it for a week and never had this).

My guess, is that when I shift hard from 1st to 2nd the engine torques hard and flexes with the race pipe in (since the 2nd cat stock had the spring bolts - it allowed it to flex more and with the rubber mount). But with the race pipe, since it just bolts on to the downpipe and the intermediate pipe, it has no room to flex. So it makes a loud flex noise.

Has anyone else noticed this? This cant be a good thing to do right?

Now, dont get me wrong, with the MS CAI, my car went from wow to WOW. With this race pipe it just went to WOOW! :shock: But with that flexing noise, it makes me kinda worried to push it.

Do most of you that have the race pipe have the Rear mount installed. If so, and you don't hear that noise, that makes sense, since your engine isnt going to be allowed to flex as much as mine, it wont put a strain on your race pipe bolts.
[/quote]

Here are my findings. I went to my Brothers-N-Laws automotive shop and we went for a spirited driving and I let them hear what I was talking about. You have to really shift it perfect to get the most amount of torque to hit (I am getting really well at speed shifting this car). When I shift it perfect b/n shifts the middle part of the car can hear a LOUD knocking noise. If its an ok shift, you don't hear anything.

We put the car up on the lift and notice 2 rub marks on the exhaust and race pipe and the bottom plates (that go below the exhaust). They made me get into my car and lifted it up again and had me rev the engine (dumping the clutch) to see how much the engine moves. It moved about 3 inches - and that is just with a dump clutch, a good shift with the weight of the car on the ground would make the thing move even more! Just dumping the clutch the whole exhaust system would come about less than an inch from hitting the bottom frame.

We put back on the stock 2nd cat and did the same test. What we noticed is the rubber mounts from the hangers keep it from doing that but it still is applying the same pressure against the exhaust from the engine torquing so hard in the bay. So before I put the lift down, I put back on my race pipe.

What does all of this mean to you, you may be asking.

Its simple, the exhaust torques so much, that by restricting the exhaust from moving (with the stock Rubber Mount with the hangers) puts even more pressure on the manifold and the turbo than the race pipe, since the race pipe allows it to flex more and put less pressure on the exhaust/manifold/turbo (because it doesn't connect to the rubber hangers). What I am saying is this - Mazda did not put alot of thought into the design of the motor mount and the exhaust. The engine moves too much! And if you try to keep the exhaust from moving too much, you are putting more pressure somewhere else. I do believe that the CAI/Race pipe added more power, hence why my car's exhaust is hitting the bottom frame. With a good shift - it literally bounces off the bottom frame about 3-4 times - like someone is hitting a hammer to it at the bottom. Thats alot of force.

Lesson of the day for me - EVERYONE NEEDS A REAR MOTOR MOUNT!

You can probably get away without having one if you don't have any mods, but even then, I do not think it is wise to not have one.

If you damage your turbo/manifold from it constantly flexing like this, I can guarantee you that most dealers will blame it on you incorrectly launching the car, and will weasel out of it (notice I said most, not all).
 

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Discussion Starter #2
Re: Mazdaspeed Owners Read! Some information that may help

Street Unit - COME OUT WITH YOUR Motor mount! I need speed dammit!
 

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Re: Mazdaspeed Owners Read! Some information that may help

Thanks for taking the time to share. Good advice for all.
 

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Re: Mazdaspeed Owners Read! Some information that may help

Kudos to you dude. Thats good information. I had my doubts on mounts previously, but that is something that add a check to the pro list.
 

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Re: Mazdaspeed Owners Read! Some information that may help

88 durometer mount ftw!
 

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Re: Mazdaspeed Owners Read! Some information that may help

[quote author=CosmicBlueMS3 link=topic=71761.msg1262780#msg1262780 date=1173715787]
88 durometer mount ftw!
[/quote]

How much power loss do you think you lose by going 70/62 as opposed to 88? I know you lose a crap ton of torque with the stock motor mount.
 

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Re: Mazdaspeed Owners Read! Some information that may help

hard to say how much power loss there, im not sure if its a matter of losing power vs a lack of ability to use the available power with a softer mount.
Im sure the 62 or 70 will be way way better than stock since the stock is so soft you can easily flex the bushing with 1 finger tip, its scary soft.
with the 88 you can hammer it and the only limitation becomes the available traction of your tires
 

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Re: Mazdaspeed Owners Read! Some information that may help

[quote author=c0ldFuzion link=topic=71761.msg1262583#msg1262583 date=1173708158]


What does all of this mean to you, you may be asking.

Its simple, the exhaust torques so much, that by restricting the exhaust from moving (with the stock Rubber Mount with the hangers) puts even more pressure on the manifold and the turbo than the race pipe, since the race pipe allows it to flex more and put less pressure on the exhaust/manifold/turbo (because it doesn't connect to the rubber hangers). What I am saying is this - Mazda did not put alot of thought into the design of the motor mount and the exhaust. The engine moves too much! [/quote]

I'm not so sure about that.

The second cat (that gets replaced by the race pipe) has spring loaded fittings with cones on both ends which will allow some movement to relieve stress. The race pipe isn't attached to the hangers but it also doesn't allow for any stress relief on either end. My guess is that the race pipe will actually put more stress on the other exhaust system components.

That being said, I do agree that firmer motor mounts are a must.
 

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Re: Mazdaspeed Owners Read! Some information that may help

i have the same setup as this and no issues. Now i don't drive like a moron, so I might not notice this flexing. engines always move a ton during torque though. the key is to keep everything clear of its path.. and/or stiffen the mounts to restrict movement. i would say that this issue if probably more isolated than common, but I am getting a new mount anyways.. actually mounts. I would like to see a full set.

good investigation... I will keep this thread in mind if I hear anything.
 

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Discussion Starter #10
Re: Mazdaspeed Owners Read! Some information that may help

[quote author=diablospeed link=topic=71761.msg1263267#msg1263267 date=1173729329]
i have the same setup as this and no issues. Now i don't drive like a moron, so I might not notice this flexing. engines always move a ton during torque though. the key is to keep everything clear of its path.. and/or stiffen the mounts to restrict movement. i would say that this issue if probably more isolated than common, but I am getting a new mount anyways.. actually mounts. I would like to see a full set.

good investigation... I will keep this thread in mind if I hear anything.
[/quote]

I dont see how my issue can be an Isolated case and not common. I test it with just the MS CAI / Race Pipe on / off. So its a pretty common setup. I doubt the CAI would make the exhaust jump that much extra to where it is banging on my bottom plate.

Like I said, you really need to shift it perfect to get the engine to really go. A sloppy shift or too long a clutch hold will not make it do it. And I am not driving like a moron. I am just shifting really quickly. Perhaps you are not shifting quick enough, or you are conservative in your shifts. Or, my Rear Motor Mount is softer than yours. I do not know.

I am not trying to make a doomsday announcement - simply trying to let people know my findings. I know each car will be different, but not different enough to justify THIS MUCH engine movement. If you dont believe me, have a person dump clutch your car and look at the bottom, I guarantee you will see that exhaust come REAL close to hitting the bottom plate if you have a race pipe.

[quote author=GT1 link=topic=71761.msg1263257#msg1263257 date=1173729067]
The second cat (that gets replaced by the race pipe) has spring loaded fittings with cones on both ends which will allow some movement to relieve stress. The race pipe isn't attached to the hangers but it also doesn't allow for any stress relief on either end. My guess is that the race pipe will actually put more stress on the other exhaust system components.

That being said, I do agree that firmer motor mounts are a must.
[/quote]

Yes, I forgot that it was spring bolted on at both ends. This would alleviate the that pressure on the turbo/manifold to some extent. But, at the same time, My bolts were very tight stock, so I do not know how much flex it would allow.
 

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Re: Mazdaspeed Owners Read! Some information that may help

This is excellent info. The first time I dropped the clutch trying to mimic the magazine test launch, the car let out a hellatious BANG ! I looked all around the rear motor mount for signs of it hitting but couldn't see anything. Didn't think to look at the exhaust. Always good to be pointed in a different direction... :?

62 shore A hardness mount, where are you?
 

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Re: Mazdaspeed Owners Read! Some information that may help

[quote author=redSpeed3 link=topic=71761.msg1263411#msg1263411 date=1173734025]
This is excellent info. The first time I dropped the clutch trying to mimic the magazine test launch, the car let out a hellatious BANG ! I looked all around the rear motor mount for signs of it hitting but couldn't see anything. Didn't think to look at the exhaust. Always good to be pointed in a different direction... :?

62 shore A hardness mount, where are you?
[/quote]

that bang could have easily been wheel hop
 

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Re: Mazdaspeed Owners Read! Some information that may help

good thing to note....but I find it hard to believe that mazda did not engineer for this. every engine moves, and therefore everything attached to it moves. our engine may move more, but I have a feeling everything will be aeeit :)
 

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Re: Mazdaspeed Owners Read! Some information that may help

I cant imagine much R&D going into the rear mounts of this car....

An upgraded mount is a VERY good and almost REQUIRED upgrade if your motor is moving 3 inches with no load on it... shit.

Cosmic sounds VERY happy with his... I wonder if a 62 will prevent wheel hop almost as well as the 88 does...
 

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Re: Mazdaspeed Owners Read! Some information that may help

At least an upgraded rear mount is a must for a consistant hard launch i have found. The slam noise from wheel hop was just to much to think of in relation to driveline damage.
For me it also saved the hks bov actuator line from getting to close to the radiator mount on hard launches. Only change at this point in time is a little vibe with the aircon on at idle.
Cheers!
 

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Re: Mazdaspeed Owners Read! Some information that may help

[quote author=zzzoom3 link=topic=71761.msg1264016#msg1264016 date=1173752035]
At least an upgraded rear mount is a must for a consistant hard launch i have found. The slam noise from wheel hop was just to much to think of in relation to driveline damage.
For me it also saved the hks bov actuator line from getting to close to the radiator mount on hard launches. Only change at this point in time is a little vibe with the aircon on at idle.
Cheers!

[/quote]

whats your durometer? thanks
 

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Re: Mazdaspeed Owners Read! Some information that may help

[quote author=Boost Addict link=topic=71761.msg1264325#msg1264325 date=1173764659]
[quote author=zzzoom3 link=topic=71761.msg1264016#msg1264016 date=1173752035]
At least an upgraded rear mount is a must for a consistant hard launch i have found. The slam noise from wheel hop was just to much to think of in relation to driveline damage.
For me it also saved the hks bov actuator line from getting to close to the radiator mount on hard launches. Only change at this point in time is a little vibe with the aircon on at idle.
Cheers!
[/quote]
whats your durometer? thanks
[/quote]

Yes. Curious to see reports from similar set ups but with varient duros...
 

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Re: Mazdaspeed Owners Read! Some information that may help

So would having hangers installed on the race pipe be a good idea .... or?
 

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Re: Mazdaspeed Owners Read! Some information that may help

so does the cat that is replaced for the racepipe have any mounting system that is taken off when installed the race pipe?
 
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