Twins for dumbies

[jngreen]

Brian Jellich is running a 66 over a 103-ish primary..

I believe he is running a S475 for his secondary, not a 66mm.




And you guys can't really compare compound setups built for a 7.3 to those built for a 6.0 or 6.4 or a cummins for that matter. You can use them for a point of reference or a starting point, but thats about it. I see a lot of 6.0 or 6.4 guys talk about running S480's as primary chargers in a big compound setup, when there are 7.3's running them as a single. Just my 2 cents.

 

[Dzchey21]

I believe he is running a S475 for his secondary, not a 66mm.




And you guys can't really compare compound setups built for a 7.3 to those built for a 6.0 or 6.4 or a cummins for that matter. You can use them for a point of reference or a starting point, but thats about it. I see a lot of 6.0 or 6.4 guys talk about running S480's as primary chargers in a big compound setup, when there are 7.3's running them as a single. Just my 2 cents.

To a point i would agree but i still think its ok to use them as a reference to know what works and what doesnt.

 

[Tree Trimmer]

junior, i believe charles said when he went to the 55, that he lost alot of low end response, but when it lit, hold on to your a$$.

is your goal big numbers, or streetability?

 

[Cat_rebel]

And you guys can't really compare compound setups built for a 7.3 to those built for a 6.0 or 6.4 or a cummins for that matter.

I agree with that statement, take a look at a 5.9L compound setup. The most common is a HX35 with a HT3b or a S475 as the big charger.

 

[juniort444e]

TT, i would honestly like both. I mean right now with my setup and current tunes. this 4202 dont light until 2500ish. And from jason's build which will be very close to what i do, hit 706, with relatively the same turbo and injectors. I know that there are differences in both of those and every truck is different. But my guess would be with better tuning and forged rods i would be somewhere around 600ish.

So in all reality i would be happy with 600-700 with the truck thats responsive around 1800-1900 and cleaning up smoke the whole way. If the 38r is going to get me there and last me a long time i would be happy with that and whatever else gets to my goals. I just dont want to have to rebuild these turbos every few years, but if need be ill get jb's for a cheaper easier rebuild.

 

[juniort444e]

Could we start a list of who used what and was successful in doing so. Maybe get a list of specs on the turbos with different injectors that proved to work with that setup.

 

[Derek@Vision Diesel]

Could we start a list of who used what and was successful in doing so. Maybe get a list of specs on the turbos with different injectors that proved to work with that setup.

That would be nice, but some guys dont like sharing haha. The ones that TRUELY are working great never speak haa

 

[juniort444e]

I know thats the hard part.

So far all i got is the 38r/47 works.

Im still wanting to be different and go a little bigger with both but still have good nice crisp spooling from a slightly bigger turbo than a 38r.

 

[V-Ref]

Which turbo is the Primary vs. the Secondary again? I see both terms getting thrown referring to both turbos in this thread.....

I'm under the impression (given the 38R/GT47 referred to throughout the thread):

Small turbo/High Pressure Turbo/Manifold Turbo/Secondary stage of compression=38R
Big Turbo/Low Pressure Turbo/Atmosphere Turbo/Primary stage of compression=GT47

Garret turbo tech references all of the above minus the Primary/Secondary deal....

Sounds like a nitpicky thing....but to encourage participation from those guys (not me) that are running successful well thought out compound setups...probably need to square that up I imagine.
opcorn:

 

[907DAVE]

You got it right, Tim.

That is something that has always bothered me, all this different terminology used confuses many people.

 

[TARM]

That is for sure the truth. I hate the different lingo as some of it can cut either way and would be correct. I always label them by their location manifold and atmosphere. No way to confuse that no matter what your level of knowledge.

 

[silverpsd_06]

Junior im in process of using the 4094r as my manifold turbo its all fitted up and ready to go and im waiting on my atmosphere to get here so i can start getting all that together i should have it running by hopefully the end of next week or a little after... Mine has a .84 housing :lookaround: what that will cause for bp i dont know but i have a feeling it will be bad and im running a 46mm gate right at the entrance to the flange.

Atmosphere is a pt106 just like brians only non-clipped and i think he has the bigger exhaust side than mine does, ill keep you posted

 

[juniort444e]

That sounds good silverpsd. Im really looking into a secondary turbo bigger then a 38r, and just want to know what spools close to it but has more cfm, that will get all my goals satisfied. Could you post up pics of your setup if you dont mind.

TT.. My current turbo is kind of like that. It wont spool til 2500 because of tuning and big exhaust housing. But once it lights and if the trans holds good enough to plant the power its freaking awesome. Absolutely love that feeling.

Also was wondering about piping the chargers together. Which one has to enter the motor first, can the secondary push psi through the primary or will that defeat the purpose.

 

[TyCorr]

That sounds good silverpsd. Im really looking into a secondary turbo bigger then a 38r, and just want to know what spools close to it but has more cfm,

TT.. My current turbo is kind of like that. It wont spool til 2500 because of tuning and big exhaust housing. But once it lights and if the trans holds good enough to plant the power its freaking awesome. Absolutely love that feeling.

Also was wondering about piping the chargers together. Which one has to enter the motor first, can the secondary push psi through the primary or will that defeat the purpose.

s366 is slightly more efficient than a 38r on paper. In a set of compounds though Im not sure that effect. As for using a 42r or 40r as a high pressure, I dont see how thats gonna help? Seems like you're assuming you need MORE than that. Im interested in what you discover but I dont see a 38r as a limitation as it'll make 40psi on its own.

The hp turbo will not be pushing anything but drive pressure through the lp turbo in response to the last sentence in your post. With the exception of you dumping the wastegate into piping to help spool your big charger.

 

[Big Bore]

That sounds good silverpsd. Im really looking into a secondary turbo bigger then a 38r, and just want to know what spools close to it but has more cfm, that will get all my goals satisfied. Could you post up pics of your setup if you dont mind.

TT.. My current turbo is kind of like that. It wont spool til 2500 because of tuning and big exhaust housing. But once it lights and if the trans holds good enough to plant the power its freaking awesome. Absolutely love that feeling.

Also was wondering about piping the chargers together. Which one has to enter the motor first, can the secondary push psi through the primary or will that defeat the purpose.

The atmo (larger charger) feeds the manifold charger on the compressor side, the manifold charger (smaller charger) feeds the atmo on the exhaust side.

 

[silverpsd_06]

There is only one charger entering the motor at any time the manifold, now some people route their plumbing a little differently.. Follow, air enters atmosphere charger, compressed now can either go to the intake side of the manifold charger or dump directly into the intercooler reversing the flow that it has now, then to the manifold charger then directly to the motor.. Now going to the compressor inlet on the manifold works just like what you have routed in with the current charger, either you cool one stage or cool two its your choice.

What i look at it is usually if any one given turbo is gonna let go it will most likely be the manifold turbo because of back pressure issues 99% of the time. Hence why most intercool both stages to save their motor from being trashed in the event of a catastrophic failure, but if for some reason your atmosphere lets go you trash both turbos.

I don't know about where you are at but complete 7.3's can be had for a lot less than replacing two turbochargers hence why i will only cool the atmosphere.

And in response to the 38r or 40r it doesn't really matter which the flow in lbs/min is not what you are after, you could literally take a 35mm inducer turbo as your high pressure as long as it had a huge exhaust side to move the drive away from itself, or a monster ass gate. The 40r is a little stouter turbo bigger all around on the exhaust, compressor, shaft.. Its your pick i just happened to be able to pick up a 40r for 1200 brand new that's why i went that route...

And yes i will be more than happy to post up pics of it all going together and exactly how i did everything for anyone that wants to know.. When i get that far LOL

 

[juniort444e]

Thank you both. Im curious as to why it wont work reversed, like how i discribed. It would make piping soooo much easier. If not im not worried, as im still determined to make this happen.

TY...I understand im not really gaining anything using a bigger charger, i just have a bone in me thats always screaming to be different. If it comes down to it i will go with a 38r. But for some reason i just want something that will move more cfm that will spool close, not exact, but close to a 38r.

 

[TyCorr]

There is only one charger entering the motor at any time the manifold, now some people route their plumbing a little differently.. Follow, air enters atmosphere charger, compressed now can either go to the intake side of the manifold charger or dump directly into the intercooler reversing the flow that it has now, then to the manifold charger then directly to the motor.. Now going to the compressor inlet on the manifold works just like what you have routed in with the current charger, either you cool one stage or cool two its your choice.

What i look at it is usually if any one given turbo is gonna let go it will most likely be the manifold turbo because of backpressure issues 99% of the time. Hence why most intercool both stages to save their motor from being trashed in the event of a catastrophic failure, but if for some reason your atmosphere lets go you trash both turbos.

I don't know about where you are at but complete 7.3's can be had for alot less than replacing two turbochargers hence why i will only cool the atmosphere.

And yes i will be more than happy to post up pics of it all going together and exactly how i did everything for anyone that wants to know.. When i get that far LOL

You've brought up some great points! Id much rather trash an ic or maybe jam up a cylinder head than gut two bb chargers. Hell even ruining a 38r would be worse than what a used motor can be had for.

 

[silverpsd_06]

Run me through how you would do it junior, just out of curiosity

Speaking my language now tycorr lol big chargers and bb's alike are mighty damn expensive, the cooler air had by both stages ic i will make up for with water when the time comes that it gets that hot..

 

[juniort444e]

The right way that everyone else does it is, exhaust flows into secondary first then into primary (big t), air side of things go...Air filter on primary as thats where it enters the first stage of compression then routed through the intercooler into the secondary into manifold.

Im thinkng of keeping the ehaust the same, prob wrong on this whole second paragraph but its worth a shot as im just brain storming here. Air side i would use the secondary turbo as a stock setup does, filter on intake part compress the air then flow through the intercooler as normal into the intake side of the atmosphere turbo then into manifolds. Im not sure how that would work with exhaust being the same but piping it that way would be a breeze to say the least. Let me know if im even close here.