18" Fi SP4 setup help

[CplCuddles]

Newbie here, I'm getting a Fi SP4 18 soon, I planned on powering it with a Crescendo BC3500. I'm putting it into my 05' Monte Carlo, But I don't know how big the box should be since I'm overpowering it. Fi recommends 6-8cuft for a ported. I have approx 36(Width)/36(Depth)/19(Height)in worth of space in my trunk to work with. I'm also wanting to tune to about 25Hz, Just wanting general opinions on whether i'm making a bad decision on what I'm wanting. I am set on the SP4 though, I like its Fs. Any help is appreciated!

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[NASTY08IMPALA 5,000+ posts]

Newbie here, I'm getting a Fi SP4 18 soon, I planned on powering it with a Crescendo BC3500. I'm putting it into my 05' Monte Carlo, But I don't know how big the box should be since I'm overpowering it. Fi recommends 6-8cuft for a ported. I have approx 36(Width)/36(Depth)/19(Height)in worth of space in my trunk to work with. I'm also wanting to tune to about 25Hz, Just wanting general opinions on whether i'm making a bad decision on what I'm wanting. I am set on the SP4 though, I like its Fs. Any help is appreciated!

Unless u build in the trunk u dont have space .u do have 36 wide and 36 deep but only 16" tall..and thats the whole trunk ..not including amp racks and batts ..u should consider a 15 or a pair of 12s.i run. Pair of hdc4 12s in my impala and my box is 1" from the top and 5" from the trunk with a amp rack behind the box and 2 batts in the spare tire well

 

[NASTY08IMPALA 5,000+ posts]

And a daily tune of 25htz is too low and not needed ..my last box was tuned at 32 and played down to 24 with authority

 

[CplCuddles]

It's 19" tall not 16.

 

[CplCuddles]

So, what do you think for tuning then? 28-30Hz?

 

[NASTY08IMPALA 5,000+ posts]

It's 19" tall not 16.

No **** but u cant slide a 19" tall box in there especially that deep 16 was as tall as i could go and my box is only 28 deep and u wana go 36

 

---------- Post added at 01:01 PM ---------- Previous post was at 01:01 PM ----------

 

So, what do you think for tuning then? 28-30Hz?

30 is as low as id ever go

 

[CplCuddles]

Honestly, I want it to hit the BEST at around 30Hz.

 

[NASTY08IMPALA 5,000+ posts]

Do you have a ho alt and batteries picked out yet?

 

---------- Post added at 01:02 PM ---------- Previous post was at 01:02 PM ----------

 

Honestly, I want it to hit the BEST at around 30Hz.

Well then tune at 30

 

[CplCuddles]

There HAS to be a way to fit an 18 in a trunk, because people do it. I wasn't saying I want my box that big, I was just saying that's the kinda space I got to work with.

 

[CplCuddles]

Not really, on the battery I was thinking XS/Stinger. The local shop around here only has Kinetik, I don't know how good they are though. I don't know much about HO alts.

 

[NASTY08IMPALA 5,000+ posts]

There HAS to be a way to fit an 18 in a trunk, because people do it. I wasn't saying I want my box that big, I was just saying that's the kinda space I got to work with.

Thats the problem ppl are cramming 18s in to inefficient spaces ..u do t have room for a drop in box for a 18 ...if u build the box in the trunk u have a chance

 

[CplCuddles]

Do you have a ho alt and batteries picked out yet? 

---------- Post added at 01:02 PM ---------- Previous post was at 01:02 PM ----------

 

Well then tune at 30

About the tuning though, I have 2 12s tuned at about 32Hz but, they dont hit 32 as good as they hit 37, so I thought that maybe if I tuned lower than 30 that it would make 30 my "peak" point

 

[NASTY08IMPALA 5,000+ posts]

Not really, on the battery I was thinking XS/Stinger. The local shop around here only has Kinetik, I don't know how good they are though. I don't know much about HO alts.

Go with mechman or singer and kinetic is pretty good..xs/ stinger is overpriced..u will need a new batt under the hood and a g31 in the back to support that amp..so ur looking at a grand just in electrical

 

[CplCuddles]

Thats the problem ppl are cramming 18s in to inefficient spaces ..u do t have room for a drop in box for a 18 ...if u build the box in the trunk u have a chance

I think that could be done, with 2 SP4 15s I would have to spend ALOT more money with upgrades than I would the single 18, and honestly I want an 18. Simply because I have never had one before.

 

[NASTY08IMPALA 5,000+ posts]

About the tuning though, I have 2 12s tuned at about 32Hz but, they dont hit 32 as good as they hit 37, so I thought that maybe if I tuned lower than 30 that it would make 30 my "peak" point

Then u have a crappy box lol ur box should peak at tuning .is it a prefab or custom made box