Why wouldn't this work? Turbos in series
 

I am trying to find a good reason not to try this:

http://www.geocities.com/cheaptrixra...equentials.jpg

I have been running a few of the IHI's on ew4/d15a3s for a while now and i know they are spooled by 2.5k and push great up to about 12psi (after that they just overheat the air).

I am running a t3/t4 now and it isnt spooled until a little after 4k but it could make 20+psi all day long.

I'm thinking the boost from the little turbo would create more exhaust to spin the big turbo so that both are on good boost by 3k. This seems like it would work well for 11-13psi of boost and eliminate my need for expensive nitrous oxide to spool the turbo.

I think it would start to cause problems if I turned the boost up past 14psi or so because the little turbo would be overworked and make the air so hot it would not be efficient. I will address that problem later unless someone tells me this is stupid now (with a good reason).

Any advice or comments or questions would be appreciated.

-Tony

Re: Why wouldn't this work? Turbos in series
 

only problem I'd see is the oil lines for the IHI turbo. It would be really low.

Re: Why wouldn't this work? Turbos in series
 

i meant to add a note to ignore the physical positioning in the picture. the drawing is only to illustrate the routing of the exhaust and intake pipes... the turbos would actually be mounted almost side by side (no oil drainage problems).

-tony

Re: Why wouldn't this work? Turbos in series
 

What's going to prevent reversion of the intake pressure when the larger turbo isn't spinning fast enough to keep the pressure in the intake?

Air, water, and electricity will flow towards the path of least resistance. I'd fear that the larger turbo will be leaking out boost prior to it's spooling up to speed.

This can also cause the smaller turbo to overspin during these conditions as well.


Just a thought,


Wink

Re: Why wouldn't this work? Turbos in series
 

that smaller turbo would just be a bottleneck. Real Sequential twins usually have some kind of air doors to isolate each turbos exhaust flow and charge air

Re: Why wouldn't this work? Turbos in series
 

I know they do stuff like this on pulling trucks/tractors.

Re: Why wouldn't this work? Turbos in series
 

I think once the T3/T4 gets spooled it will overspool the lil IHI.

Re: Why wouldn't this work? Turbos in series
 

cause i made the chart wrong

http://memimage.cardomain.net/member...7_359_full.jpg

Re: Why wouldn't this work? Turbos in series
 

The second drawing is more of what I had in mind. The intercooler would have to kick ass because the charge temps would be quite high.

Re: Why wouldn't this work? Turbos in series
 

When the smaller turbo spools, the air will be forced into you intake mani and probably back out through the bigger turbo. When the larger turbo finally spools the higher boost will probably put a decent amount of back pressure on the smaller turbo and maybe even cause it to flutter or over spool. You need some kind of proportioning valve as someone said ealier. Maybe some way to redirect air flow depending on what rpm or boost your seeing. Just a like a turbo/supercharger application.