My Z
- Thread starter v8z4
- Start date
dmo said:Havent seen a v12 on a z4 before..haha. Very nice example, what sound system / speakers you got that amp hooked up to?
Hehe, I've had that amp for near 15 years. I bought it brand new for my first car when I turned 16, then moved it to my camaro, then into my truck. It's a bit big/heavy compared to the "modern" amps out there, but to this day it still makes plenty of power and sounds clean, so I just can't justify spending money for something new. At this rate my grand-kids will be using it.
The system is made up of a Kenwood Excelon KDC-X996 headunit, RCAs down the console, the V12 amp, and the factory "10 speaker system" speakers.
The factory amp has a channel output for each individual speaker (10 channels with my 10 speaker system). Because my amp is a 5 channel model (4 + sub), I went about doing some strategic (and actually very effective outcome) hooking up of speakers:
- The door mids and tweets are on amp channels 1 and 2, being fed the headunit "front" RCA signal. I used a 2-way crossover to connect the mids and tweets, basically turning them into a 4" component set. I set the amp's 1&2 crossover to high-pass at 200Hz (highest setting on the amp), with no crossover on the headunit front channel.
- The kick pannel midbass speakers are on amp channels 3 and 4 and are driven by the headunit's "rear" RCA output. The amp is set to a low-pass crossover at 200Hz and the headunit "rear" is set to a high-pass of 80Hz.
- The two factory 6" subs are 2ohm and thus are wired in series to make a 4ohm load (the subs are the only 2ohm speakers in the car). They are on channel 5 (the sub channel) and are set to low-pass of 80Hz.
- The "rear" speakers (the little ones over the subs) are removed.
This setup has made it possible for me to adjust each "set" of channels to provide a very close to ideal consistency across the frequency ranges. In particular, the "midbass" speakers in the kicks really help bring the bass forward and allow me to push the subs harder. Even the factory subs manage to give some decent thumping on tech/rap/etc. Eventually I'd like to upgrade the mids/tweets but that's WAY WAY WAY down the road. I'll probably just wait till a speaker gets old then replace.
ben g said:
Yeah I pulled the roll hoop covers very soon after I bought the car because I never liked them (they were the #1 thing I DIDN'T like about the Z4). With the covers on, the roll hoops look more like headrests to me. To me, roll hoops should look like roll hoops. Could just be a personal thing (though a number of people here have said they like it), but to me they now look like they are there to serve a purpose and thus give the car a bit more of a "race" look.
Typical AZ sunset. 8)
yg54sg said:wow very small! I thought it might be some kind of car audio capacitor
When I went M-style exhaust, I had to remove the battery compartment (the big bucket in the floor of the trunk). I then looked at mounting the factory battery where the Ms do, however it killed trunk space. So I ditched the 50lb battery for a 12lb Odyssey PC680. Besides not loosing any trunk space, it made quite a noticeable improvement in acceleration and handling.
I just have to be careful to remember I don't have a lot of reserve battery. I have become religious about not doing ANYTHING with the engine off. Crank engine, THEN put top/windows down. With care though it has never failed to crank reliably.
I imagine there is an improvement, will this upset weight distribution though? the battery on the Z4 is huge for a car, its even larger than the one on our old 4.5 tonne iveco van! I think I might be a due a new one soon, ignition on while coding the other week for about 30 minutes and it nearly didnt crank... the bettery is 8 years old mind...
yg54sg said:
It will change the weight distribution "some" for two reasons, however I'll explain why the net result is positive.
- First, simply moving the factory battery forward to the M location will move weight towards the center of the car. This however is a very good thing, as ideally all weight should be directly centered between the front and rear wheels (would provide a perfect 50/50 split). The further weight is moved to either end, the more the increase in polar moment that occurs. An increased polar moment decreases response time and makes the vehicle feel heavier in corners.
I don't remember if you ever did this experiment, but it's the old spinning chair model. http://www.youtube.com/watch?v=u7X2DYgubAE Note how when her arms/legs are in tight, she spins faster. Further out, she spins slower.
Here is a video of the calculation. http://www.youtube.com/watch?v=EQYo4krdT60
- Second, reducing the weight of the battery will reduce the overall vehicle mass. I find literature stating the Zs have a weight distribution anywhere from 49.2/50.8 to 50/50 split. For simplicity, lets say it is truly 50/50. My car weighs 2880lbs full of fuel, so 1440lbs front/rear. The swap to a light weight battery would have changed the weight split to 1440/1400 front/rear (2840 total). That still works out to 50.7/49.3 split. So in the end, while yes the weight split is a bit forward now, the vehicle is still basically a 50/50 split. However now the engine/tires/suspension/brakes all have 40lbs less to deal with during acceleration/deceleration/turning.
So.. in then end, getting a light weight battery mounted towards center of car is a good thing in all aspects!
I quite like the license plate!
