Non Sequential (Should I)

[allstaruk]

Cool, hassle free power thats what I am looking for, although now I need to find somwhere to get my wastgate milled out on the cheep.

A

[probedb]

Do you have any guides on converting to NS the proper way? I\'ll make my own choice but I may as well look into it while everything is off the car

[allstaruk]

I do i\'m in a rush at the mo, will post tomorrow.

A

[probedb]

I do i\'m in a rush at the mo, will post tomorrow.

A

Much appreciated

[RobbieRX-7]

This looks apropiate http://www.rx7club.com/showthread.php?t=576777 But if i were you i would think long and hard about this because by the sound of it after reading various posts, it aint as much fun as seqential mode especially under 3800rpm. Over that rpm range it is in non sequential mode anyway so you wont feel any difference. Im tempted to do this mod myself but just scared incase i hate it and want it changed back to sequential??

[probedb]

Yeah I\'ll be umming and ahhing over this...hopefully getting a large street port so don\'t know if that helps the turbos spool up time or not...I\'m still learning

[stylus350]

This looks apropiate http://www.rx7club.com/showthread.php?t=576777 But if i were you i would think long and hard about this because by the sound of it after reading various posts, it aint as much fun as seqential mode especially under 3800rpm. Over that rpm range it is in non sequential mode anyway so you wont feel any difference. Im tempted to do this mod myself but just scared incase i hate it and want it changed back to sequential??

Could you not do the poor mans way first? Im sure this is easily reversed. Then, if you like it do it the proper way?

[allstaruk]

I\'ve got two sets of turbo\'s so I\'m safe if i don\'t like it then it cam just go back to seqential.

a

[John Yorke]

Going non-seq. for me was a big mistake, it is nothing like running a propper single be it small, medium or large. As people have said before me the reason for Mazda developing this system [with all its faults] was to give low down turbo response, by dissableling that you end up with a 300bhp car that has nothing to write home about below 4.5k and this notion that by going non seq. will give you more power is cr#p can you please tell me how you expect to get more power from the same turbos flowing the same boost but are operating together rather than seq.
If you have the same sized compressors ect. how do you expect to flow more through the engine, by porting the wastegate you might improve the exhaust flow but not enough to see any significant gains.
Do the non seq. by all means because of boost problems but dont expect tons more power, dont be fooled by the big kick at 4.5k that is just both turbos spooling up together.
HTH

[RobbieRX-7]

This was taken from the us forum by a member on there....

So I went non sequential to see what the hype is all about. From what I read my set up was perfect for it since it would yield a quicker spool time (Mild Streetport, CAI, PFS SMIC, straight through exhaust. Many claim 10 psi @ 3000 RPMs I thought "great! Win win situation". The reality is that I don\'t get full boost till 3800 RPMs (like many others). Yes I did increase my powerband by 700 RPMs but there is lag. Oh the damn lag... Even at 4200 RPMs the boost is not anywhere instant like the stock system.

Forget all that though. Here are some real world results:

My best friend has an 05 porsche boxter S, not a bad little car actually. I think stock for stock the performance factor goes to the faggot porsche. 280 HP NA, mid engine car (which is great for handling, and launching. For those of you that don\'t know) and weighs about the same as an FD. My buddy and I have been racing each other since we were 16 (in our parent\'s car). Now that we are in our 30\'s **** still the same lol just the cars got faster and nicer. Ok now I\'m rambling...

When he first got his porsche. My mods were: sequential turbos, Mild Streetport, CAI, PFS SMIC, DP, MP, Stock catback, Stock ECU Boost held @ 10psi. We went from a first gear roll. I pulled on him instantly and just left him behind. It was like that with any gear any speed, except during a dig where he would jump ahead by 1/2 a car but by the end of first I was already next to him.

Now: on top of those mods I have non-sequential turbos, RB duals, TUNED power FC, and I\'m running 2 psi more (12 psi). The outcome is that he always jumps at least 1 - 1/2 cars ahead and I always have to play catch up. From a 1st gear roll he leaves me behind (by quite a bit actually), on the middle of second I catch up to him and leave him about a car behind on the top of second, on third he is way back. Even on +80 MPH rolls he gets the jump but I catch up rather quickly and yeah I could brake boost but that\'s not the point. BTW he is 100% stock.

The truth of the matter is that going non-sequential does simplify your setup thus making it easeir to trouble shoot, adds lag, and increases your powerband by 700 RPM\'s. But that 700 RPM increase is actually nothing to be proud of since it has two things working against it: One is the lag (of course) the other is that when you shift at redline your revs drop to what? 4600 RPM\'s. But that\'s exactly where the sequential turbo system is runing the turbos in parallel. So you aren\'t really utilizing those extra 700 RPMs anyway . So what are you left with then? lag and simplicity. That\'s all.

For those that are thinking of going non-sequential: I recommend you try the simplified sequential instead. I believe it\'s only 20 hoses + solenoids so the simplicity is still there. I would go to simplified seq setup myself but my turbos are old and smoke quite bit so I just may go single instead.

The thread is here if you want more info http://www.rx7club.com/showthread.php?t=596489&page=1&pp=15&highlight=sequential

[allstaruk]

Hmmhh, interesting reading there, I am under no illusions that I will gain any power I\'m just fed up fixing boost problems, I think I\'d prefer a working seqential set up but I\'m just getting fed up fixing it.

[dj_dee99]

I\'m very happy with my non-sequential set up. Has the plus side of being able to drive off boost quite nicely. But if you want to boot it, then it\'s all just a gear-change away!

[TRex]

Allstar, you\'re on the right track bud!

 Forget the rubbish people talk about lag and power difference etc, their experience of Turbo charged cars are obviously limited to a Twin turbo system running seq.

 
 If it\'s less hassel, trouble free car and less confusion and mess in the engine room, then yes you want to run the Turbo\'s parallel. (non seq)

[John Yorke]

Allstar, you\'re on the right track bud!

 Forget the rubbish people talk about lag and power difference etc, their experience of Turbo charged cars are obviously limited to a Twin turbo system running seq.

 
 If it\'s less hassel, trouble free car and less confusion and mess in the engine room, then yes you want to run the Turbo\'s parallel. (non seq)

Rubish smubish, I can only tell you how I found it, if you want to run non seq. good luck, you now have a much less responsive car than before, yet to see one fly past me in what ever guise be it twins or single, simplified twins fine but dont delude yourself running non will give you a better car it dont [imho]

[John Yorke]

This was taken from the us forum by a member on there....

So I went non sequential to see what the hype is all about. From what I read ... Even at 4200 RPMs the boost is not anywhere instant like the stock system.

Enough said

Forget all that though. Here are some real world results:

My best friend has an 05 porsche boxter S, not a bad little car actually. I think stock for stock the performance factor goes to the faggot porsche. 280 HP NA, mid engine car (which is great for handling, and launching. For those of you that don\'t know) and weighs about the same as an FD. My buddy and I have been racing each other since we were 16 (in our parent\'s car). Now that we are in our 30\'s **** still the same lol just the cars got faster and nicer. Ok now I\'m rambling...

When he first got his porsche. My mods were: sequential turbos, Mild Streetport, CAI, PFS SMIC, DP, MP, Stock catback, Stock ECU Boost held @ 10psi. We went from a first gear roll. I pulled on him instantly and just left him behind. It was like that with any gear any speed, except during a dig where he would jump ahead by 1/2 a car but by the end of first I was already next to him.

Now: on top of those mods I have non-sequential turbos, RB duals, TUNED power FC, and I\'m running 2 psi more (12 psi). The outcome is that he always jumps at least 1 - 1/2 cars ahead and I always have to play catch up. From a 1st gear roll he leaves me behind (by quite a bit actually), on the middle of second I catch up to him and leave him about a car behind on the top of second, on third he is way back. Even on +80 MPH rolls he gets the jump but I catch up rather quickly and yeah I could brake boost but that\'s not the point. BTW he is 100% stock.

Only reason he has the extra umph is the .2 bar increase in boost

The truth of the matter is that going non-sequential does simplify your setup thus making it easeir to trouble shoot, adds lag, and increases your powerband by 700 RPM\'s. But that 700 RPM increase is actually nothing to be proud of since it has two things working against it: One is the lag (of course) the other is that when you shift at redline your revs drop to what? 4600 RPM\'s. But that\'s exactly where the sequential turbo system is runing the turbos in parallel. So you aren\'t really utilizing those extra 700 RPMs anyway . So what are you left with then? lag and simplicity. That\'s all.

For those that are thinking of going non-sequential: I recommend you try the simplified sequential instead. I believe it\'s only 20 hoses + solenoids so the simplicity is still there. I would go to simplified seq setup myself but my turbos are old and smoke quite bit so I just may go single instead.

The thread is here if you want more info http://www.rx7club.com/showthread.php?t=596489&page=1&pp=15&highlght=sequential

Think that says it all
Anyone want to disprove my answers? it is quite easy - put your car on the rollers [with the twins running as they should] and compare once you have done the conversion like I did and you will come to a similar conclusion.
I am not talking about comparing an engine with non boosting turbos against a conversion but when everything is working OK.