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-   -   non-sequential (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/non-sequential-614422/)

Rex7-93 Jan 17, 2007 01:38 PM

also with 3" all the way back

Authentikdit Jan 17, 2007 01:41 PM


Originally Posted by rynberg
The stockers spool a hair faster than the BNRs.

Then what makes the BNRs an upgrade?Are they just able to handle a lot more power?

NissanConvert Jan 17, 2007 01:46 PM


Originally Posted by Authentikdit
Then what makes the BNRs an upgrade?Are they just able to handle a lot more power?

that, durability, and new-ness.

So i was looking at the diagram and how the sequential system actually works

after ~4500 both turbos are spooled. wtf is the point of non sequentials if even on sequential turbos you're eventually spooling both turbos. :wallbash: it just makes no sense... you wait longer, you get little to no advantage except a cleaner engine bay. myself, running poor mans i don't even get that!

snub disphenoid Jan 17, 2007 01:50 PM

I dunno, I think sequential will give you a LOT more torque and a much more useable powerband. I wish Steve Kan had started my dyno runs earlier (like around 2000rpm) when he was tuning my car, because my turbos actually start spooling around 1300rpm (stock port motor). Around 2000rpm I start to feel a wave of torque build, and then from 2500rpm on, it's just a linear delivery of power all the way to redline.

But from what I see on my dyno graph (run began at 3000rpm), in third gear, I reach 250 lb.-ft. of torque from 3000rpm on, and that's with a peak torque figure of 280 lb.-ft. and a peak power of 302rwhp. The turbos take about 400rpm to go from vacuum to fully spooled.

I've never run these turbos non-sequential, but I get the feeling I wouldn't like it. I reminisce about driving my upgraded single turbo FC, and I remember how utterly torqueless that car could be. It seriously gets frustrating if you have to wait until 3000rpm to see any positive manifold pressure.

I'm taking a little extra effort to keep the twins sequential, because I like never needing to downshift, even if I'm going 55mph on the freeway. Just floor it and before you know it you're going 80.

P.S. I run Knightsports twins.

Mahjik Jan 17, 2007 01:54 PM


Originally Posted by NissanConvert
tafter ~4500 both turbos are spooled. wtf is the point of non sequentials if even on sequential turbos you're eventually spooling both turbos. it just makes no sense... you wait longer, you get little to no advantage except a cleaner engine bay. myself, running poor mans i don't even get that!

Yes, you get a little cleaner looking engine bay.

For some people (and track guys), the non-seq setup is predictable. As in, they don't have to worry about the transition causing a problem. You also have a little bit more power at that 4500 rpms range because the sequential system has the boost dips a bit at that point when the secondary turbo comes online. However, with a properly functioning system, the transition should be almost non-existent.

For me, those differences don't out way the loss but for quite a few it does.

Also, the stock sequential system can become problematic if you are shooting for numbers over 370-380rwhp. That's another reason some guys (gals) go non-seq as they are going more top end power. It's not for everyone, but it is for some. ;)

Rex7-93 Jan 17, 2007 01:56 PM

There is alot less things that can go wrong/break if your running non seq. you dont have to worry about all the solenoids, and old vaccum lines. All that rats next under the UIM is gone. Its just simplicity. That is the main reason im going non. seq. I have had too many problems with the seq. and i wont mind waiting a bit longer for the boost.

czseven Jan 17, 2007 02:14 PM

I am in the process right now of going non seq, I would half to agree tired of trouble shooting shit had to replace turbos anaway. so i think i will benifit from doing this in the future.

NissanConvert Jan 17, 2007 04:11 PM

Okedoke, so how hard is it to un-do poor-mans? I might shoot for big numbers but not on my stock turbos. That said i do sometimes kinda enjoy juking the backside sideways in first and second when the boost hits. But then sometimes i don't like getting squirrelly...

rx7will Jan 17, 2007 11:27 PM

Things i dont like about the poor mans way, i never tried the full non sequential:

Boost creep
Louder exhaust
Lag.

I thought i liked the poor mans nonsequential at first, but it was horrible. My car would have a major boost creep problem if I give the car partial throttle, especially on the freeway. It would go from 7psi to 15psi and never stop rising. I would have to lift each time. The exhaust was louder, i loved the way it sounded if i was at full throttle. At idle it was okay and light throttle was bearable. It did not bother me much untill i got on the freeway. If i'm going about 70mph, the car was really loud and would droan horribly. But if i would go about 85mph, the droanding would go away. Plus it makes fifth gear useless. You can step on it and it does nothing. I know fifth gear is for cruise but it would take forever for the boost to build. With the sequential system 5th gear is actually useable and boost is there instantly. So cruising on the freeway on a long trip was very bad experience, and it was after a long trip that i decided to go back to sequential.

My car has intake, down pipe, hi flow cat, pfs exhaust, pfs intercooler and pettit ecu. The exhaust tone was very reasonable before the switch to the poor mans version. My fd had the newer 99 and up twins and it worked perfect. But i just wanted to try the poor mans version. I was unhappy with it and was going to try the full version. But i decided to go back to the sequential system, but i did port the wastegate.

I later got a pfc for my car and played around with the boost settings and now the sequential system is even better. I am so glad that i went back to sequential, it makes the car a lot more enjoyable to drive.

Speed of light Jan 18, 2007 01:56 AM


Originally Posted by rynberg
Nissan, I am getting 15 psi from ~3k rpm to redline. This is in lower gears. Obviously on the freeway, going slow in 5th gear, it is quite possible to hit 15 psi below 2500 rpm. I still can't figure out why people go non-sequential for a street-driven car.

I can't figure it out either... I get boost almost instantly, even under 2000 rpm, and usually several psi at that. This makes a tremendous difference in the drivability of the car, period. And the transition to secondary boost happens so fast it's inconsequential.

The reality is that Time = HP and I hit the gas and GO. I'm well down the road while the other guy is spooling up. It'll take him a hell of a lot more HP to make up for the lost time and catch me. Just can't defy the laws of physics, regardless of how you rationalize it.


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