HomemadeTurbo - DIY Turbo Forum

HomemadeTurbo - DIY Turbo Forum (https://www.homemadeturbo.com/)
-   Forced Induction (https://www.homemadeturbo.com/forced-induction-7/)
-   -   sequential turbo (https://www.homemadeturbo.com/forced-induction-7/sequential-turbo-14670/)

Reddy 01-29-2004 05:42 PM

Re:sequential turbo
 
Alright, this is the way I would do it. I would have a custom manifold with 8 runners. 4 would be going into the one turbo. The other 4 would be going into the other turbo. An actuator would block the exhaust flow from the 2nd one. At a certain psi and rpm I would have the actuator open up and allow both turbos to spin at the same time. I think its a bad idea to have a turbo on the downpipe of another.

Honda16hb 01-29-2004 06:45 PM

Re:sequential turbo
 
I hadn't thought about that idea. Why are you so against turbo on dp action? I don't think you ever told me.

dewme5 01-29-2004 08:27 PM

Re:sequential turbo
 
you can make more power then your engine can handle, using the normal single turbo. Why complicate things, make things more expensive, and get more headaches? Just to say you did it?

VATN technology was being used to do this simpler, but still is a worthless pain in the ass unless you want to be the guy with more money then brains.

Maybe you can run some NOS on it too. Toss in a side of propane injection, and maybe an air to water intercooler while you are at it.

Reddy 01-29-2004 09:32 PM

Re:sequential turbo
 
I'm so against putting a turbo on a downpipe becuase that can't be good for performance. You have to be losing exhaust velocity by running it through the turbine wheel than to a turbo. I mean think about it.

Honda16hb 01-30-2004 10:58 AM

Re:sequential turbo
 
ok, I didn't think about the lost velocity before, but witht the bypass I gain that velocity back once the 14b is cut out. With your 8 runner manifold design the exhaust flow is split between 2 sources, so the 14b won't have such great response.

just to say I did it is exactly why I will complicate things, you only live once, might as well enjoy it.

Jakal 01-30-2004 02:15 PM

Re:sequential turbo
 
could u not just run in in sort of a twin layout where u have the smaller turbo off 2 exhast ports and the larger off the other two? i mean the little one would spool a hell of a lot faster the the big one on only two that way the larger one kicks in when the smaller one is already making full boost...

Jakal 01-30-2004 02:18 PM

Re:sequential turbo
 
or u could run them both off of all four with a y pipe off of the stock mani.. the exhasut will take the path of less resistance which is obvious so will it spin the wheel thats allready spinning to capacity or try and spin the slower, larger wheel? would that not still be sequential if one turbo spools after the other?

Honda16hb 01-30-2004 11:22 PM

Re:sequential turbo
 
2 cylinders will never spool a t4, at least not in the rpm range I'm looking at. your second idea will just over spool the 14b, unless I put in a wastegate then all the exhaust will just get thrown away. I'm glad that you shared your ideas, I just didn't think they were very well thought up, keep reading and you will learn more.


that 8 runners idea sounded good to me again today when I remembered that I can put a valve in to shut off exhaust flow in front of the 14b, I'll think about that one more. Does anyone have specs on the size of the supra and rx-7 bypass valves? I didn't find much in my google searches, mostly just non-sequential conversions, what haters. If anyone sees some sequential setups on ebay for cheap post a link here please. and by cheap I mean $50 or so.

scarecrowX 01-31-2004 04:49 PM

Re:sequential turbo
 

Originally Posted by Whitey
I'm so against putting a turbo on a downpipe becuase that can't be good for performance. You have to be losing exhaust velocity by running it through the turbine wheel than to a turbo. I mean think about it.

it's not only the lost velocity affecting the second turbo that's going to hurt your performance. the second turbo is also a restriction in the exhaust path of the first turbo. turbo's spool efficiently based on the pressure differential before and after the turbo. with the second turbo on the dp of the first, there will be less pressure differential between the manifold and the turbine outlet (high pressure on both sides of the turbine), increasing the lag on the first turbo as well.

keep in mind too that temperature is a very important aspect of velocity in a pipe. the temperature differential between the manifold and the dp post-turbo is pretty big. that's where you're losing a lot of your velocity.

personally, i'd look into anti-lag. but i understand why you want to do it this way, and i say more power to ya.

i like the diverter valve idea. supply exhaust to both turbos, then pinch off or restrict the smaller one when the big one catches up. my guess is that wastegate actuators would be able to effecitvly control butterfly/diverter valves.

Reddy 01-31-2004 05:41 PM

Re:sequential turbo
 
Very good advice, Anti-lag is ------- awesome but apparently it kills your turbos. There is an antilag program on the EMS but I'm afraid to try it and you also have to run a 5th injector for the true antilag setup

Honda16hb 02-01-2004 03:30 PM

Re:sequential turbo
 
the thing to remember with butterfly valves is that exhaust is hot, so they will expand, and exhaust is dirty, so they might get locked open or shut.

I'm officially putting this idea on hold for the time being. I lack the fabrication skills and money to git r done, I'm just going to focus on getting my LS/VTEC single turbo done right now.

hotrex 02-01-2004 03:49 PM

Re:sequential turbo
 
its about time you came to your senses fool....

Honda16hb 02-01-2004 09:18 PM

Re:sequential turbo
 
you shouldn't be jumping to conclusions, I'm going to try this later, once I have more experience with turbo and everything, I'm still crazy.

Krystian Anarkist 01-26-2017 10:39 PM


Originally Posted by stretch-d (Post 128612)
Check into the reed valves that two stroke motocross bikes use.

Might be adaptable in some way.

Edit: May be rob some of the parts off some one's RX7 system that they took off.


Originally Posted by Reddy (Post 128576)
Dear god it will NEVER work. Sequential is IMPOSSIBLE to get it to function correctly. simply impossible. Also you can't connect a turbo to a downpipe.


if you seriousely dont believe that you cant connect a turbo to a downpipe than you should not even be giving advice on turbo chargomg what so ever. obviousely you dont have a clue what your talking about and have very little experience with turbo set ups and engines in general for that matter. anyone with a basic understanding of how a turbo set up works would knw 100% that it can be done with very little effort. anybody with that same basic knowledge and the ability to weld would be able to attach a turbo to a downpipe in under an hour. if you already know you dont know what your talking about then dont advice. also i wouldnt recomend that you do any work to any cars you arnt prepared to scrap because not only do you not have a clue but the fact that you think you know enough to start giving advice to people on forums is evidence that everything you think you know about engines and turbocharging could not be farther from reality.

Krystian Anarkist 01-26-2017 10:46 PM


Originally Posted by Reddy (Post 132378)
A Yamaha Banshee is a 4-wheeler. 350cc 2stroke twin cylinder. (107mph top speed) Hotrex is right, don't go crazy with dumping lots of money into this thing. I mean I spent under $350 on mine and it was only going on a d-series. You have to be prepared that it might not work and you have to throw it in the trash.


chances are you dont even own a yamaha banshee lmao. Because if you did you would probably know that they are not all 350cc. Learn how to use google and you wont have to throw your turbo setups in the trash anymore. How much have you really soent on your setup? You have been caught talkin out your ass 3 times already in the ten minutes ive been reading so im willing to bet you soent more than 350 just paying a mechanic to bolt the turbo on for you.

saablord 02-06-2017 07:22 PM

1 Attachment(s)
Looks like this Krystian only signed up to roast this guy. lmfao.

Anyways, I do have something to contribute here. I've been doing it safe with my turbo setup on my saab, but now it's time to make some HP.

At first my plan was to just get two small turbos and run one per cylinder pair (1/4 and 2/3 in the B235's case). It'd be cheaper than a bigger twinscroll garrett and just fun to do.

But.... what if I put a valve after one turbo's exhaust to disable it and link the two manifolds together at first to spool one turbo quickly and then separate them again in the upper range. aka parallel sequential just like the Supra/RX7/Subaru boxer twin except id keep the turbos on their own cylinder pairs.

I drew it out in the attached image.

As for controlling the valves...
-bypass would be normally open
-high end turbo shut off would be normally closed
-check valve on pressure side of high end turbo takes care of it self.
-Once the low end turbo reaches 75% of its max boost, the shut off valve would open. This creates a blending region.
-close the bypass shortly there after.


Thoughts?
Is it worth it to keep the turbos separate? I could just throw all the cylinders together, have two turbo mounts and have a shut off after one turbo.


All times are GMT -5. The time now is 06:49 PM.


© 2024 MH Sub I, LLC dba Internet Brands