New turbo has arrived

[turboshad]

Please add a scattershield to your to do list

That was done last year and I do feel a bit safer now. I would like to find the real world limit of Chris' purple clutch. I know there is a 650whp "dyno queen" out there but I'm curious how far it will go at the strip. So far not a single sign of slipping so I'm feeling good.

[Vigo]

That is a REALLY nice turbo combo for your motor and goals! It's clear you've done your homework there.. can't wait to hear what it does on the car.

I hope you are right about it spooling better than Lengel's combo..

[Shadow]

I think I can get full spool in the 4500-5000 range but we'll see if I'm dreaming. Time will tell but if I can do that then it will still in my opinion be quite fun on the street. I'd also like to bump up the shift points to 8500 next year.

IF you could get it to spool that quick, it would be outstanding! Still a fun driver IMO. I would be impressed to say the least!

If not, you still have 1000 more rpm of PB than I do, so spooling 1000rpm later won't be the end of the world. Did you ever dyno to see where your peak power is?

[turboshad]

IF you could get it to spool that quick, it would be outstanding!

I guess I'll just take that as a challenge.

[turbovanman²]

.82 T4 housing, dang,

Can't wait to see how fast your car will be, do I hear 8's?

Why plug the water holes if you don't use the, just leave them open.

[Shadow]

I guess I'll just take that as a challenge.

That's what I would do.

LFI This turbo will typically spool between 5600-6000 rpm on a 4 cyl. (P-trim size turbine in a housing that big) You have the larger than usual exhaust outlet which I think will help with spool. One must remember this is a divided housing, so it's closer to a .68 open. (volume wise) which will also help spool more than the equivilent open .84 A/R. + whatever benefit from the "Comp turbo" mod.

What I'm most interested in is What valve your going to use, seeing that your making a twin scroll divided mani? All the quick spool valves I've seen either use an open mani (have to or you'd cut off one side of the mtr) Or they have it right in the turbine housing.

Something new? I think 5000rpm is doable, less than that and your Rock'in it!

I was originally thinking you will have too much TQ with a set-up like this for drag racing, but then I realized you Don't Have to run the quick spool All the time! Either way, should be interesting and deff looking forward to seeing it worked out!

[turboshad]

Correct me if I'm wrong, but I always assumed a .84 divided would have the same flow area as a .84 open. It's cross sectional area over radius so the division isn't counted.

Something new?

This ^^^^ Guessing spool is a bit of a crap shoot so we'll just have to see when it is done. I'll be sure to go out and log a 3rd gear 2000RPM pull with the current setup to see how it compares to the new setup.

Why plug the water holes if you don't use the, just leave them open.

To keep crap out of there and there is something hacker to me about seeing open water ports.

[Shadow]

Correct me if I'm wrong, but I always assumed a .84 divided would have the same flow area as a .84 open. It's cross sectional area over radius so the division isn't counted.

My understanding is that the divided "wall" material is what you loose in volume vs open scroll.

This ^^^^ Guessing spool is a bit of a crap shoot so we'll just have to see when it is done. I'll be sure to go out and log a 3rd gear 2000RPM pull with the current setup to see how it compares to the new setup.

Deff compile some data from the Holset for comparo. I'll be watching this Very closely as it's deff something I've been curious about. Make sure you have pr taps in that new mani!!!!!!

[Shadow]

That was done last year and I do feel a bit safer now. I would like to find the real world limit of Chris' purple clutch. I know there is a 650whp "dyno queen" out there but I'm curious how far it will go at the strip. So far not a single sign of slipping so I'm feeling good.

Glad your going to do this as I'm also curious. As far as I can tell, you Should be at the limit of what I thought it would take right now. FAMOF I wouldn't be surprised If it's slipping a bit Right now.

First thing that will go on a ceramic puc clutch is your 60'. Remember, No smell or any other idication until you over-power it enough that it completly lets go.

Until then it will just slip enough that you will loose time in the lower gears until you run on a track that hooks you hard enough to slip it enough (heat) that it will only recover with cooling.

Unless you can datalog your engine rpm vs axel rpm you would never know. Been there, done that!

This was exactly what I was trying to get across years ago when I was looking for a clutch for the Charger. Unfortunatly (like most of what I post) it was lost on most.

[turboshad]

My understanding is that the divided "wall" material is what you loose in volume vs open scroll.

I just can't see that being the case. It would negate the whole ratio and make the two styles completely non-comparable.

I would expect to be able to see any clutch slip as an inconsistency in RPM climb which I haven't seen yet. The new display I will be putting in will be able to log anything on the MS plus some extra pressures (oil, fuel, exhaust), temps (tire and EGT), the VSS sensor and GPS speed. It should make for some interesting logs. The sucky part about a divided header is you now need two of everything.

[BadAssPerformance]

The sucky part about a divided header is you now need two of everything.

Jeeze, not everything.. only need one twin scroll turbo

[Shadow]

I just can't see that being the case. It would negate the whole ratio and make the two styles completely non-comparable.

I'm sure your aware of how "iffy" that ratio is right? You've seen how it's calculated? I've looked at divided scroll housings and to the naked eye, it certainly looks like the divider robs volume from the housing. Side wall thickness is the same, as is the opening to the manifold.

[shayne]

you do loose volume with a divided housing, but you are right still because the ratio itself isnt changed, the simple proof of statement is the divided t4 inlet still needs to fit in standard t4 inlet size, so the inlet area is less off the bat, and as a result to keep the ratio in check the discharge area also is smaller than a non divided .82 housing. the ratio itself is not inclusive with actual volume of the scroll.

[turboshad]

I'm sure your aware of how "iffy" that ratio is right? You've seen how it's calculated? I've looked at divided scroll housings and to the naked eye, it certainly looks like the divider robs volume from the housing. Side wall thickness is the same, as is the opening to the manifold.

No, I can't say I've actually "seen" how it was calculated. Have you? It's not a rocket science number especially when everything is designed on computer. I'd be curious to see the exact same A/R both divided and open beside each other. Sure the flange will look smaller with the divided b/c it has to fit a standard but what does it look like at the point where it hits the "turbine circle" so to speak? This is about where I would expect the true A/R to start which poses some fun when trying to measure it.

[Shadow]

Well that's the million $ Q! No one seems to know, or I haven't found definitive info on Exactly Where the area measurement is taken. I do know that the two housings I was holding (I think they were .82 or .96?) Looked physically the same size. (outside casting)

Anyway, thought it was a Good thing that the dual scroll would be more responsive, but I guess by your response you were hoping it would be Full A/R?

You must have come across this before? I remember reading on the Supra forums (? Maybe Subaru?) + others where they were having the Great dual vs open spool vs power debate. It was common knowlege that, when going dual scroll, to UP it one A/R size for same volume flow. (at least that's what they were selling you on at the time)

[BadAssPerformance]

From the A/R ratio definition, it is not "where the measurement is taken" but instead "how the equation defines the cross sectional area in relation to the radius from the center" so by design, the singal and dual will have the same x-sectional area, if they have the same A/R...

...however, if the manufacturers cheat and put the "dual" wall in the middle of the same (casting) core, then no wonder they spool faster, LOL!

[turboshad]

No, I haven't come across that one. If this were true it washes out all claims of a divided housing getting better spool for the same A/R since it would be the area decrease and subsequent velocity increase that caused it and not the division. Either way I think I'm sitting pretty good. Anyone know the phone number to an engineer that designs turbine manifolds?

Edit, JT beat me to the same punchline.

[BadAssPerformance]

Anyone know the phone number to an engineer that designs turbine manifolds?

Edit, JT beat me to the same punchline.

That pesky JT and the reaction time, LOL

If you mean "engineer that designs tubrines and housings?" Yes, I know a couple... and this thread makes me want to call them, BUT you didnt buy yoru turbo from either of the companies I know folks at, so maybe call the manuf you got your turbo from and ask them for some single/dual housing dimentions?

[Force Fed Mopar]

My theory would be that it is flowing the same volume, but through 2 small holes instead of one large one, which will give the same flow but w/ higher velocity. Same idea as using 2 small valves instead of 1 large one Maybe I'm crazy or over-simplifying it though.

[lengel]

I think I can get full spool in the 4500-5000 range but we'll see if I'm dreaming. Time will tell but if I can do that then it will still in my opinion be quite fun on the street. I'd also like to bump up the shift points to 8500 next year.

WoW nice turbo! DJ when you say full spool in the 4500-5000 range. How much boost are you refering to? I think you have a good chance at spooling that turbo in that rpm range. I think I remeber reading somewhere that ball bearing turbos spool around 10% faster then journal bearing turbos. Anyway looking forward to how this works out for you.


Adam