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Seq to nonseq to Seq: review

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Old Jun 3, 2007 | 12:35 AM
  #1  
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Seq to nonseq to Seq: review

A while back my Sequential system failed and I could not find the line causing leak because I didnt have time to pull the UIM off so I did a poor man non-seq. While the non-seq did feel pretty fast when all the boost dumped on, there was so much lag it killed me *sequential spoiled me rotten*. I recently tore it down found the lines, and reverted to sequential.. Goddamn I love sequential! To anyone who is wanting to go poor man non-seq over your current sequential.. dont do it! I used new silicone lines and used some loctite on the nipples.. Those suckers are not going anywhere. Anyways thats it for me, just thought Id post this for future reference when somone wants to go non-seq.

~Cosmo
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Old Jun 3, 2007 | 06:50 AM
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From what I'm told, non-sequential has some required supporting mods to be effective. Without them you will experiance what you just described, much lag.
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Old Jun 3, 2007 | 07:15 AM
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Think of it people... you would prefer POWER! than HANG THE F*** ON!(seq) or No power, than HANG THE F*** ON! (non seq) Seq all the way!
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Old Jun 3, 2007 | 12:23 PM
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im definately keeping my sequential system. that is until i go single in the distant future
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Old Jun 3, 2007 | 12:35 PM
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i love the seq system.. never will i go non seq.. i dont think i will go single unless i get another 7... which wont be anytime soooon.. i love that power right there
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Old Jun 3, 2007 | 01:16 PM
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sequential is much better on a street driven car for the most part.Working out all the kinks and doing silicone hoses is well worth the time.
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Old Jun 3, 2007 | 05:31 PM
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Just go out and see for yourself how much time you spend under the 3000rpm line using all the power... You'll see it will be worthless.

People who want the seq system is because they are sopligt racers or just want to let the girls hear the dump valve wissle when cruising through the city.

Non seq simplifies the system, with supporting mods (DP, CB) it will reduce lag to the 3500-4500 rpm range which will get you in thesame spot as most single turbo's .

I would be more than glad to stay out of boost under 4000rpm, alowing me to downtune the fuelmap in that range for economical highway cruising, and a rich upper rpmband tune when boost hits.
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Old Jun 3, 2007 | 05:37 PM
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i got a sill question but when your on the highway and crusing your not bosting right its on vacume untill you acually press the pedal?... so why would you say you want to stay out of boost under 4k rpm? when your not really in boost... am i right or wrong?
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Old Jun 3, 2007 | 08:58 PM
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The rich mans non seq is way better than the poor mans non seq .Try it you will like it .The good combo is the BNR stage three set with the rich mans non seq .I am running the BNR third stage super sized with the rich mans non seq .and I have no desire to go single .
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Old Jun 3, 2007 | 10:20 PM
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The seq system is outdated, unnecessary, overcomplicated technology. While the best path is pure single turbo, non-seq done correctly is plenty decent.

Also, why do the seq-lovers continually ignore the 1->2 drop as if the power band is constant? It isn't. Either you get initial quick spool of 1st + delayed spool of 2nd with stock seq or you get overall initial slower spool of both. The latter is much more linear and predictable and hence superior in practice. It's also a non-issue once the turbos are already spooled.

The stock sequential system is a pure hack - a necessary one (at the time) borne mainly out of the fact that BB turbo technology was not as widely available or economically feasible.
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Old Jun 3, 2007 | 10:53 PM
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Attempt to rationalize it anyway you guys want, but the truth is that it is a matter of preference.

My preference is for quick spooling power and torque as I spend a lot of time under 3000 RPM.

I'd hardly call it a hack but I agree that there are other options out there now.
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Old Jun 3, 2007 | 11:07 PM
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You know how to downshift right? Flooring it @ 2000 rpm isn't the best method for performance, seq or non-seq.
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Old Jun 3, 2007 | 11:50 PM
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Again, its a matter of preference.

I don't want to be *forced* to downshift so that I have enough power for a quick overtaking or lane change driving in traffic. With the sequential, I just stretch my right foot and the power is there now. Rather than downshift, accelerate, decelerate, upshift.

Welcome back Clayne. Haven't read any posts from you in ages.
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Old Jun 4, 2007 | 12:10 AM
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Originally Posted by clayne
You know how to downshift right? Flooring it @ 2000 rpm isn't the best method for performance, seq or non-seq.
If you autox, you'll be lucky if you get above 2nd gear. Single isn't always the way for everyone. If you autox and have a single kit that doesn't see full boost until 4k-4.5k, then you might as well not have one at all. Not to mention that the kit itself puts you in a different running category.
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Old Jun 4, 2007 | 12:55 AM
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I think it really depends what the car is being used for.

Frequently Street driven, auto-x.. seq system all the way, Quick spool in lower rpm really helps in these.

Track driven, cayon driven = non seq all the way, Linear power band really helps in these, as it is more predicatable.

Just my 2 cents.
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Old Jun 4, 2007 | 01:02 AM
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I own two FD's. A completely stock one and a single turbo(Apex'i RX6) with full exhaust.
I much prefer the stock sequential twin setup for street driving.
RX6 turbo is relatively small and has BB center section for quick spool, but there is really no comparison to the stock sequential setup.
I see benefits of both setups as discussed in countless threads on the board.
A healthy stock sequential setup is a thing of beauty, but the truth is not many are so healthy... I'll bet most people complaining about the sequential setup probably has never driven one in good condition.
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Old Jun 5, 2007 | 09:38 AM
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You Americans are way too much used/spoiled driving auto cars, being too lazy to downshift.
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Old Jun 5, 2007 | 11:07 AM
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It has nothing to do with being lazy to downshift....the problem is you guys always jump into these threads saying downshift to race.... WE ARE NOT TALKING ABOUT RACING. It's a simple matter of pleasurable throttle response when just tooling around or cruising on the highway. It's called low-end torque (well...sort of). I really don't understand why this concept is hard to understand.

I no longer daily drive my FD, so the low-end throttle response and seq isn't as important to me as it once was, but in that type of situation seq is FAR superior to non-seq or single turbo.
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Old Jun 5, 2007 | 12:23 PM
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Originally Posted by Speedworks
Just go out and see for yourself how much time you spend under the 3000rpm line using all the power... You'll see it will be worthless.

People who want the seq system is because they are sopligt racers or just want to let the girls hear the dump valve wissle when cruising through the city.

Non seq simplifies the system, with supporting mods (DP, CB) it will reduce lag to the 3500-4500 rpm range which will get you in thesame spot as most single turbo's .

I would be more than glad to stay out of boost under 4000rpm, alowing me to downtune the fuelmap in that range for economical highway cruising, and a rich upper rpmband tune when boost hits.

Originally Posted by Speedworks
You Americans are way too much used/spoiled driving auto cars, being too lazy to downshift.


Ok. I have read enough of your bullshit. Get off your damn soapbox and post something useful. I have continually read posts of yours that are pointlessly degrading and pose no informational basis at all. Stop looking down on anyone who does things differently than you. YOU are not the god of cars. YOU are not the genius that knows RX7's perfectly. You are an egotistical-holier-than-thou, stuck-up, gotta-be-my-way-or-it-sucks dick-head.



As for your statements. in regards to your first of this thread. have you ever done anything besides freeway runs and street driving? For some reason, I can tell you have never auto-crossed. I can also tell you are unfamiliar with the aspect of application of power-band. just because it makes a more "linear" power-band doesn't mean it makes the best power-band for a given driver or application.

Learn. Then Speak.

And as for your racist comment: (and yes, I consider Americans a melting pot race, and your statement is assuming the same) Where the heck did laziness and automatics come into this. Try not letting your ADD show through so much. Instead of posting useless banter, get with the program. Just because you are not American.. does not give you the right to bring comments like that into play. Take your bigotry elsewhere.

And here's an IDEA for you. if you want to start correcting everyone else and then being a dick and assuming ALL Americans are automatic-loving lazy-asses... then you should perhaps clean up your own posts first. USE THE SPELL-CHECK. And don't you dare pull the "English is a second language to me and I am using a translator" excuse. That is all it is. You don't like it? Get off an English based forum. Or perhaps learn the language better before ridiculing Americans as a whole.
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Old Jun 5, 2007 | 12:31 PM
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Originally Posted by rynberg
It has nothing to do with being lazy to downshift....the problem is you guys always jump into these threads saying downshift to race.... WE ARE NOT TALKING ABOUT RACING. It's a simple matter of pleasurable throttle response when just tooling around or cruising on the highway. It's called low-end torque (well...sort of). I really don't understand why this concept is hard to understand.

I no longer daily drive my FD, so the low-end throttle response and seq isn't as important to me as it once was, but in that type of situation seq is FAR superior to non-seq or single turbo.
Tyler has an excellent point. If it were in a racing situation an fd with any turbo set up will be able to put down good hp due to the higher rpms. On the street though I mainly cruise around doing 2500 rpm's or so. I want a turbo that will allow me to peg it in lower gears and be able to pull itself out with little or no problems or hesitations, and maybe a downshift if im cruising on the freeway.

My fd now has an RX-6 kit on it, but I used to own a sequential one before. The low end pull is definitly noticible, but to me the overall increase in power and the best part of having linear power dilivery makes it worth the split second difference in quick spool. In the end its about personal preference, which is based a lot upon how each car is driven and for what puspose.
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Old Jun 6, 2007 | 09:16 AM
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Originally Posted by Monkman33
Ok. I have read enough of your bullshit. Get off your damn soapbox and post something useful. I have continually read posts of yours that are pointlessly degrading and pose no informational basis at all. Stop looking down on anyone who does things differently than you. YOU are not the god of cars. YOU are not the genius that knows RX7's perfectly. You are an egotistical-holier-than-thou, stuck-up, gotta-be-my-way-or-it-sucks dick-head.



As for your statements. in regards to your first of this thread. have you ever done anything besides freeway runs and street driving? For some reason, I can tell you have never auto-crossed. I can also tell you are unfamiliar with the aspect of application of power-band. just because it makes a more "linear" power-band doesn't mean it makes the best power-band for a given driver or application.

Learn. Then Speak.

And as for your racist comment: (and yes, I consider Americans a melting pot race, and your statement is assuming the same) Where the heck did laziness and automatics come into this. Try not letting your ADD show through so much. Instead of posting useless banter, get with the program. Just because you are not American.. does not give you the right to bring comments like that into play. Take your bigotry elsewhere.

And here's an IDEA for you. if you want to start correcting everyone else and then being a dick and assuming ALL Americans are automatic-loving lazy-asses... then you should perhaps clean up your own posts first. USE THE SPELL-CHECK. And don't you dare pull the "English is a second language to me and I am using a translator" excuse. That is all it is. You don't like it? Get off an English based forum. Or perhaps learn the language better before ridiculing Americans as a whole.


Make my day Monkeyman... I've owned 2 FD's in the past 4 years and spent more time on the net trying to learn than I spend on anything else.

I'm not a racist 'friend', I'm just itred of people posting thesame question over and over again. Do a search and this thread wouldn't even have been necessary.

Oh, and which of my posts are you refering to? There are no stupid questions... only stupid answers... like yours.
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Old Jun 6, 2007 | 07:05 PM
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Originally Posted by SportCoupe2
From what I'm told, non-sequential has some required supporting mods to be effective. Without them you will experiance what you just described, much lag.


True but the difference is very minimal. Though you will see some slight improvement when going full non-seq, the fact is you don't get enough exhaust energy from the little 13b to spool both turbos (with the crappy factory manifold) fast enough in the low range to make up for the lost of the sequential set-up. Whomever told you that needs to sit down and compare two dyno charts of both seq and non-seq. It's a total night and day difference below 4k.
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Old Jun 6, 2007 | 07:16 PM
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With no other changes made I can really see how a non-seq couldn't compare to stock sequential turbs. What are some things that can be done during a full non-sequential conversion to lessen the differance from sequential twin turbos?

I would say #1 would be a full exhaust. Any other mods that will improve the spool-up of a full non-seq conversion keeping the stock twins? Lets pretent cost isn't a factor first.
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Old Jun 6, 2007 | 09:28 PM
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From: next to the polishing wheel!!!
The rich mans non seq helps the spool up.With money to spend I think making an exhaust manifold from start to finish will help alot . I have plans to do this when I get time ,After the K1 BMW is painted .The main thing for me is the angles and thickness must be the same as my modifed manifold and the spacer for the super sized BNRs .I have all hard pipes with no desire to remake any of them . Beside open exhast a good design cold air intake will help as well . Simple air piping without alot of bends will help . With a front mount innercooler designed and piped as rotorbrains , the flow is better than one with a bunch of snakes running all over the place . Getting the double throttle plates and that webbing out of the upper intake will help as well . How we do go on ,we all know this stuff . Good night .
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Old Jun 6, 2007 | 09:30 PM
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Cost isn't a factor? Any other mods that will improve a full non-seq conversion? Okay: GT-35R.

Cost is always a factor in these types of things. That being said I would not recommend non-seq to someone without flow mods. Actually I just wouldn't recommend anything involving the stock turbos. It's like trying to sell you on a 27" Sharp TV from 1988 when Sony WEGAs are available.
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