Sequential vs. Non Sequential
02-20-22, 01:05 PM
#27
To put things in perspective, I overlay my 10 year old sequential dyno chart with his NS chart since we are both running similar boost, and by no mean mine is 100% as I can't get the primary up to 14psi so my boost pattern is only 12-9-14, but even that sequential is the clear winner here.
MS Print is definitely not the right tool to use here but I don't have the dyno log, just a PDF, so I just try to line up the X and Y with the best of my ability.
Thought this should settle things a bit, and if I did anything wrong please let me know
02-20-22, 05:29 PM
#28
Noise, response, adrenaline, smoothness….as much as Sequential is a PITA when it’s not right, it’s brilliant when it is. I’ve now got 50-60 miles and a 3-4 hours run time on my small street port 7670 setup and I’ve begun boosting it up to 55-6000rpms and while it’s responsive, it’s just not the same lunge down low as the sequential twins. Weather is starting to get better and I’ll try to get more miles on it soon to crank boost up to 16-17psi but I still believe it won’t replicate the sequential experience, matter of fact, I know it won’t.
02-20-22, 05:33 PM
#29
That's so little compare to what you lose out down low, and that is in the ideal world when everything is in tip top condition too right?
To put things in perspective, I overlay my 10 year old sequential dyno chart with his NS chart since we are both running similar boost, and by no mean mine is 100% as I can't get the primary up to 14psi so my boost pattern is only 12-9-14, but even that sequential is the clear winner here.
MS Print is definitely not the right tool to use here but I don't have the dyno log, just a PDF, so I just try to line up the X and Y with the best of my ability.
Thought this should settle things a bit, and if I did anything wrong please let me know
To put things in perspective, I overlay my 10 year old sequential dyno chart with his NS chart since we are both running similar boost, and by no mean mine is 100% as I can't get the primary up to 14psi so my boost pattern is only 12-9-14, but even that sequential is the clear winner here.
MS Print is definitely not the right tool to use here but I don't have the dyno log, just a PDF, so I just try to line up the X and Y with the best of my ability.
Thought this should settle things a bit, and if I did anything wrong please let me know
For OP, look at the 150 ftlbs of torque advantage down low for the sequential car….no way to argue it. Mazda got it right 30 years ago, we have all chased replicating the experience but with double the power. Not possible to date on a 2 rotor. I’d still love to see a stock port 3 rotor run high boost on an 8374.
The following users liked this post:
ZE Power MX6 (02-20-22)
02-21-22, 12:49 PM
#30
Having owned a single turbo T-78 RX-7 (in early 2000s, so EFR didn't exist), non sequential RX-7, and sequential turbo RX-7s... the sequential wins hands down for everyday use and abuse. No lag. Instant torque. Plenty of power.
I think going single turbo is good for someone looking to simplify the setup when they are either 1) done fixing the twins, or 2) looking for insane power. This car doesn't need insane power. And other than being able to say, my car makes X RWHP, it doesn't matter because nowhere can you use X RWHP on the roads legally. In the end, it becomes a talking point and show piece. Just my 2 cents. I just don't see why anyone would do non-sequential when there are cheaper single turbo options out there nowadays.
I think going single turbo is good for someone looking to simplify the setup when they are either 1) done fixing the twins, or 2) looking for insane power. This car doesn't need insane power. And other than being able to say, my car makes X RWHP, it doesn't matter because nowhere can you use X RWHP on the roads legally. In the end, it becomes a talking point and show piece. Just my 2 cents. I just don't see why anyone would do non-sequential when there are cheaper single turbo options out there nowadays.
02-21-22, 02:45 PM
#31
RX-7 Bad Ass
iTrader: (55)
Non-sequential had its place in time. Back when there were no good single turbo options and you were looking to find more power.
Those days are gone. RIP.
If you want power and/or simplicity, go Borg Warner. If your twins don't work right, there are PAGES of how-to's and advice on troubleshooting and getting them working right.
The only thing you get with non-sequential is you can point to the empty space under the upper intake manifold and say "I cleaned all that up!". Good for you, your car is now slower.
Dale
Those days are gone. RIP.
If you want power and/or simplicity, go Borg Warner. If your twins don't work right, there are PAGES of how-to's and advice on troubleshooting and getting them working right.
The only thing you get with non-sequential is you can point to the empty space under the upper intake manifold and say "I cleaned all that up!". Good for you, your car is now slower.
Dale
The following 8 users liked this post by DaleClark:
Akagis_white_comet (02-22-22),
c0rbin9 (02-21-22),
HiWire (02-21-22),
Jatt (02-21-22),
rotaryextreme (02-22-22),
and 3 others liked this post.
The following users liked this post:
mr2peak (03-09-22)
I swear, I almost spit out my coffee when I read that lol...
The following users liked this post:
estevan62274 (02-23-22)
02-23-22, 01:58 PM
#37
Here are my .02c:
This could just be the STEM & business side of me talking, but from the start the video seemed like it already had an inherent bias which negates the purpose of the video. The cars also didn't have much of an established baseline: We obviously known they had a stock car, a sequential, and a non sequential. Modifications varied, and compression on all of them were unknown. My main point of argument here is that there were far too many unknowns to form data with any real credibility to it.
I'm not trying to discount the attempt to do this comparison, but I think it could have been done differently.
This could just be the STEM & business side of me talking, but from the start the video seemed like it already had an inherent bias which negates the purpose of the video. The cars also didn't have much of an established baseline: We obviously known they had a stock car, a sequential, and a non sequential. Modifications varied, and compression on all of them were unknown. My main point of argument here is that there were far too many unknowns to form data with any real credibility to it.
I'm not trying to discount the attempt to do this comparison, but I think it could have been done differently.
Last edited by SwappedNA; 02-23-22 at 02:27 PM.
02-23-22, 02:20 PM
#38
Eats, Sleeps, Dreams Rotary
iTrader: (2)
sequential to non sequential
meat to impossible meat
it's not worth it trying to convert things that are supposed to be a certain way... lol
non-seq is just a low budget single
i don't know why we still compare these 2 when we should really be comparing non-seq to single turbo - right?
meat to impossible meat
it's not worth it trying to convert things that are supposed to be a certain way... lol
non-seq is just a low budget single
i don't know why we still compare these 2 when we should really be comparing non-seq to single turbo - right?
The following 4 users liked this post by rotaryextreme:
03-02-22, 04:15 PM
#39
Eye In The Sky
iTrader: (2)
Join Date: Feb 2001
Location: In A Disfunctional World
Posts: 7,896
Likes: 0
Received 114 Likes
on
66 Posts
As I always stated, it depends on your driving style. Do drive like your car has a V8 and auto trans or do you like to use the gears and keep the rpms higher.
The prior for seq and the later for non-seq.
The prior for seq and the later for non-seq.
03-04-22, 05:10 PM
#41
Eye In The Sky
iTrader: (2)
Join Date: Feb 2001
Location: In A Disfunctional World
Posts: 7,896
Likes: 0
Received 114 Likes
on
66 Posts
Otherwise it’s just an awesome rationalization for intentionally being lazy and not fully enjoying what the car can do when driven correctly more intensively.
The knife cuts both ways.
The knife cuts both ways.
03-04-22, 07:44 PM
#42
You are going to feel the missing low rpm torque on non-sequential every time you accelerate from a stop.
Unless your "driving style" is to hold the revs at 5,000rpm and slip the clutch at every stop.
For racing it might be an acceptable simplification at the expense of driveability like locking the timing on a car with a distributor.
Unless your "driving style" is to hold the revs at 5,000rpm and slip the clutch at every stop.
For racing it might be an acceptable simplification at the expense of driveability like locking the timing on a car with a distributor.
03-05-22, 08:45 AM
#43
Being lazy is removing parts and welding up others from the sequential system…usually when something goes wrong. That’s also always intentional. The rationalization, since it’s ‘as you always stated’, is telling yourself and others that it’s an improvement for a streeted car while insinuating the rest of us are just keeping it because we would prefer a V8 auto. You’re not the enlightened one and repeating it won’t make it so.
Last edited by Sgtblue; 03-05-22 at 09:10 AM.
03-07-22, 08:22 AM
#44
Rotary Enthusiast
I have to agree with sequential or go with a Borg..... the instant boost I get with the sequential is awesome. I am running the "SP"s at a solid 14psi now and I am very pleased. I've been in a few singles so far and on the street I don't see how they can compare to be honest. Even on the highway I will get a jump, but I am sure many would reel me in. I do like the building of boost experience. It feels awesome!!!, but it is like smoking tires. Very cool, but your not getting anywhere. Going non sequential would only be justified for a budget and do it your selfer..... nothing wrong with that, but it would make no sense to me at all. You can keep the 10 extra HP on the top. BTW, I don't drive mine like a V8. I drive it like I drove my non turbo FC 20 years ago.
Thanks for the thread though. I love seeing these!! I still need to get mine to a dyno. I am just being cheap at this stage I guess.
Thanks for the thread though. I love seeing these!! I still need to get mine to a dyno. I am just being cheap at this stage I guess.
03-07-22, 06:44 PM
#45
Eye In The Sky
iTrader: (2)
Join Date: Feb 2001
Location: In A Disfunctional World
Posts: 7,896
Likes: 0
Received 114 Likes
on
66 Posts
You are going to feel the missing low rpm torque on non-sequential every time you accelerate from a stop.
Unless your "driving style" is to hold the revs at 5,000rpm and slip the clutch at every stop.
For racing it might be an acceptable simplification at the expense of driveability like locking the timing on a car with a distributor.
Unless your "driving style" is to hold the revs at 5,000rpm and slip the clutch at every stop.
For racing it might be an acceptable simplification at the expense of driveability like locking the timing on a car with a distributor.
That will spin the wheels so easily in first that seq is then obsolete.
Having owned a TR3, Alfa Romeo GT1300JR stock and class D modified, and a 83 RX7 12A with 185 whp, my love and driving style is different.
03-08-22, 04:24 PM
#46
Rotary Freak
Originally Posted by Testrun
Going non sequential would only be justified for a budget and do it your selfer..... nothing wrong with that, but it would make no sense to me at all. You can keep the 10 extra HP on the top.
We were forced by a rule change to remove a single turbo and reinstall twins several years ago - thankfully reversed since. Rather than get another ecu and rewire the car, elected to run them non sequentially. Did find around 20kw extra over the last time the car ran seq......I assume the bloke in the vid has left all the flapper ***** in situ, a la poorman, in the manifold to only net 10hp.
Ideally you'd laser cut a flange to mate with the turbos and make a proper manifold rather than stuff around grinding and welding the cast iron lump, I'm sure there would be additional back pressure and power advantages over the less than straightforward gas path required, even in the modded stocker.
03-08-22, 10:58 PM
#47
tldr: nothing will change my mind 
had to take a small hiatus to handle some real life stuff but i would rather the conversation go without me anyway. are you wanting me to perpetuate the discussion lol the video seems somewhat adequate in saying whatever needs to be said... to me anyway. the nit picking at the data and how xyz wasnt provided i can do without though. i asked what information you guys wanted with the test and i provided that and more. as i said though, i'll be doing it again anyway. there was a small discrepancy with the dyno operator that skewed the data a bit. not enough to toss out the test but enough where i want to do it again.
also i mentioned in another thread, all of us here have the same capability to do things like this. theres nothing stopping anyone from doing this test themselves with whatever data points THEY want. im inviting literally anyone else to do this. if the way i did the test, presented the information and if the data points i logged are inadequate then do it yourself lol. there are no rules to what you choose to do with your free time but if youre going to FOX news the test then go get the information yourself and present it in a way that you deem sufficient.
regardless of the data and based on my own driving experience and doing the conversion for others, non sequential wins every time. on paper a lot of things look like a lot of things but in the real world the data doesnt always translate. in terms of driving experience and maintenance, non sequential is superior. this is my stance and it will not change. a stock fd with a properly working sequential system i fully stand on the side of leaving it be. im not so pro non-seq that i think every seq car should be converted BUT in a given set of circumstances, its much better choice than troubleshooting an improperly functioning seq system to an extent.
its also kind of confusing since there are so few single turbo set ups that produce a functional 10psi below 3k but no one is NOT going single for that reason. with so much hoo rah for the sequential system, whats the point in going single if the driving experience is so great as is? this dreadful, experience ruining lag is a fair trade for an increase in horsepower measured by the 100s though... it would seem the exchange has its limits in terms of acceptability in this circumstance.
my GRAND reason for being such an advocate for the non-seq is simplicity and predictability. 2 things that i simply can not get enough of in the automotive world. all of the things that come with getting the system to work as it did 30 years ago in exchange for 10psi below 3k...... no where on planet cr-rex is this exchange fair, reasonable or rationale. we all have different preferences in what we want from these cars that serve no purpose other than automotive enjoyment in all its categories. whatever you enjoy from your machine, go for it and enjoy but i will continue to be an advocate for the "laggy" non seq.
and for @djseven, of the 100+ cars youve converted how many came back and said they were unhappy with the conversion? and if its so bad, why did you do it so many times? did you not inform all these people that it would turn the car into a turd?
i think the most important thing to this whole comparison is what the owners of the non-seq cars have to say. if the overwhelming majority of the people that have done the conversion enjoy it more than the seq then nothing else matters. this discussion is more so for people who havent made a decision yet and hopefully its enough to scare them to NOT do it but go single and deal with the exact same lag but with a much greater power increase. the line seems to be fuzzy when it comes to defining lag, the fd and its turbo set up. in non-seq form, the lag seems to be absolutely unacceptable but if it were a true single with all the exact same benefits of a non-seq then the exact same lag isnt a problem at all? idk... there may be a hole in my logic here
anyway......... dead horse. i think the discussion has hit all the possible points for pro/anti, pluses and minuses, pros and cons and so on. i have one last push with this comparison in performing the test again and i will leave it alone. it will be some time before that happens but its coming.
i do love you guys though. this level of passion can only be brought to life by TRUE enthusiast and i appreciate it very much
had to take a small hiatus to handle some real life stuff but i would rather the conversation go without me anyway. are you wanting me to perpetuate the discussion lol the video seems somewhat adequate in saying whatever needs to be said... to me anyway. the nit picking at the data and how xyz wasnt provided i can do without though. i asked what information you guys wanted with the test and i provided that and more. as i said though, i'll be doing it again anyway. there was a small discrepancy with the dyno operator that skewed the data a bit. not enough to toss out the test but enough where i want to do it again.
also i mentioned in another thread, all of us here have the same capability to do things like this. theres nothing stopping anyone from doing this test themselves with whatever data points THEY want. im inviting literally anyone else to do this. if the way i did the test, presented the information and if the data points i logged are inadequate then do it yourself lol. there are no rules to what you choose to do with your free time but if youre going to FOX news the test then go get the information yourself and present it in a way that you deem sufficient.
regardless of the data and based on my own driving experience and doing the conversion for others, non sequential wins every time. on paper a lot of things look like a lot of things but in the real world the data doesnt always translate. in terms of driving experience and maintenance, non sequential is superior. this is my stance and it will not change. a stock fd with a properly working sequential system i fully stand on the side of leaving it be. im not so pro non-seq that i think every seq car should be converted BUT in a given set of circumstances, its much better choice than troubleshooting an improperly functioning seq system to an extent.
its also kind of confusing since there are so few single turbo set ups that produce a functional 10psi below 3k but no one is NOT going single for that reason. with so much hoo rah for the sequential system, whats the point in going single if the driving experience is so great as is? this dreadful, experience ruining lag is a fair trade for an increase in horsepower measured by the 100s though... it would seem the exchange has its limits in terms of acceptability in this circumstance.
my GRAND reason for being such an advocate for the non-seq is simplicity and predictability. 2 things that i simply can not get enough of in the automotive world. all of the things that come with getting the system to work as it did 30 years ago in exchange for 10psi below 3k...... no where on planet cr-rex is this exchange fair, reasonable or rationale. we all have different preferences in what we want from these cars that serve no purpose other than automotive enjoyment in all its categories. whatever you enjoy from your machine, go for it and enjoy but i will continue to be an advocate for the "laggy" non seq.
and for @djseven, of the 100+ cars youve converted how many came back and said they were unhappy with the conversion? and if its so bad, why did you do it so many times? did you not inform all these people that it would turn the car into a turd?
i think the most important thing to this whole comparison is what the owners of the non-seq cars have to say. if the overwhelming majority of the people that have done the conversion enjoy it more than the seq then nothing else matters. this discussion is more so for people who havent made a decision yet and hopefully its enough to scare them to NOT do it but go single and deal with the exact same lag but with a much greater power increase. the line seems to be fuzzy when it comes to defining lag, the fd and its turbo set up. in non-seq form, the lag seems to be absolutely unacceptable but if it were a true single with all the exact same benefits of a non-seq then the exact same lag isnt a problem at all? idk... there may be a hole in my logic here
anyway......... dead horse. i think the discussion has hit all the possible points for pro/anti, pluses and minuses, pros and cons and so on. i have one last push with this comparison in performing the test again and i will leave it alone. it will be some time before that happens but its coming.
i do love you guys though. this level of passion can only be brought to life by TRUE enthusiast and i appreciate it very much
03-08-22, 11:40 PM
#48
regardless of the data and based on my own driving experience and doing the conversion for others, non sequential wins every time. on paper a lot of things look like a lot of things but in the real world the data doesnt always translate. in terms of driving experience and maintenance, non sequential is superior. this is my stance and it will not change. a stock fd with a properly working sequential system i fully stand on the side of leaving it be. im not so pro non-seq that i think every seq car should be converted BUT in a given set of circumstances, its much better choice than troubleshooting an improperly functioning seq system to an extent.
Test result that doesn't match real world data usually mean one thing, your test is flaw.As far as driving experience, how are the comparison done? Seq vs non-seq both on 10psi or you have folks driving a 14psi non-seq and comparing to their non-functional stock seq?
03-09-22, 01:27 PM
#49
Rotary Enthusiast
A proper single gives a hundred+ HP, gains that are impossible with the twins. That makes the lag "acceptable", because the power is otherwise unachievable. The lag from non-sequential is a choice, you can make the same power (within 3%) by maintaining what is already there.
What we really want, is the single gain with the sequential response, and that is why the EFRs are so popular. Because even with our hundred+ HP gain, we still aren't exactly happy with lag.
Small singles that make the same power as twins but with more lag, I will never understand. I think these setups are mostly racing rules requirements, or heat soak requirements. Could also be budget and time restrictions, which unfortunately dictate most of the things in this world, without making it a better world.
03-09-22, 04:08 PM
#50
Rotary Enthusiast
I am sorry to keep this going, but it brings up a question that I've had a hard time getting an answer I can understand. Awhile ago I was running on just the primary as I was having an issue with the sequential system (I had the damn pre controller plug reversed). I guess that would technically be a problem with myself and nothing to do with the system... anyway, the car made a solid 12 psi. It was holding it's own on the track, but I was wondering how much power I had lost without the secondary online. I had a couple "knowledgeable people" tell me not much power is lost as it is at 12psi. 12 psi is 12psi. I am guessing these people don't take into the account efficiency? Like the charge temp itself? 12psi with both turbos kicking should result in a much cooler charge resulting in a more cfm correct? Am I looking at this wrong? If I have that right then why would the non sequential make more power on the top end vs mid range? Is there more flow through the manifold the way it is modded? What am I missing? I would think maybe the non would pick up some mid then taper back off to equal the sequential. I need to go review cfm vs psi again I guess.