64.5 vs 66 SXE spool difference?

chad256

chad256

Lurkin
Joined
Oct 27, 2011
Messages
103
I'm getting ready to up-size my secondary on my 12v, and am considering an s364.5sxe. But I'm wondering if an s366sxe may be a good choice with a little room to grow with in the future. both would be the 74mm turbine wheels. Currently have a 480 as the primary.

My main question is if you guys think there will be a noticeable difference in how quick each will light, considering that the turbine wheel and exhaust side will be the same size, and the only difference is the compressor wheel.

The truck doesn't tow and quick spooling isn't really a requirement, but i don't want to make it a complete dog either.
Thanks.
 
64.5sxe vs 66 is a big exducer difference so for sake of power 66sxe. 80lbs per min vs. 95lbs.
 
I think it's a mistake to run that bigger slower spooling turbine unless you plan to run a non-gated setup. I went for a quick spooling HE351CW/S480 to a slower spooling S363/68 turbine and picked up ZERO horsepower on our chassis dyno. I lost about 100 ft lbs of torque, increased cruising and towing egt, and the only positive gain was 2400+ RPM performance... truck doesn't lay over as quickly on the top end. Now granted I'm only fueling it to about 600 HP but.... we have other test vehicles with similar results, monster high pressure turbos do not generally increase HP.
 
Currently running a 62/65/14 that I was told was a 62/71. I just feel like I may be pushing this secondary hard in regards to drive pressure, (but I don't have a dp gauge), especially when I spray, although I do have an external gate that vents to atmosphere.
 
So why not go down to the parts store and buy a cheap oil pressure gauge and check drive pressure?
 
Will hit the nail on the head. Generally, a snappy quick spooling truck is more enjoyable to drive all around. The mechanical street trucks need all of the help they can get in this department. The 65 and 68 turbines are a good fit for most applications. If drive pressure on the secondary is of concern then do as Jacob said and test it. If drive pressure is high start pursuing other means of relieving pressure. I much prefer an external gate dumping into the hot pipe around the secondary over making the high pressure charger larger.

Remember, people want compounds for power AND quick spool up. Going from the smallest S300 frame turbine wheel to the largest is going to make a big difference.
 
You may be unhappy with the 366. Way more turbo than you need for the power level you are at. A larger turbine with a 62 or 64 compressor would work well and be able to handle your air needs well into the mid 800's on fuel only(with S480 primary).
 
Big Blue24 said:
I think it's a mistake to run that bigger slower spooling turbine unless you plan to run a non-gated setup. I went for a quick spooling HE351CW/S480 to a slower spooling S363/68 turbine and picked up ZERO horsepower on our chassis dyno. I lost about 100 ft lbs of torque, increased cruising and towing egt, and the only positive gain was 2400+ RPM performance... truck doesn't lay over as quickly on the top end. Now granted I'm only fueling it to about 600 HP but.... we have other test vehicles with similar results, monster high pressure turbos do not generally increase HP.
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Can you post up graphs? I want to see how much further out it could carry the hp vs making more.
 
I am mainly only concerned with my drive pressure when spraying nitrous. My current external gate opens once drive pressure exceeds boost pressure. I am leery to dump the e gate into the hot pipe in fear of over-spinning the 480.

I just feel like the truck could benefit from going to a little bigger secondary, Maybe the 64.5/68 would be a good option? I may also upgrade to a 483 or larger and some point in the future.

The truck is fun the way it spools and drives currently, but at this point i'm looking for more on the top end
 
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Without measuring primary boost and drive pressure you are just taking shots in the dark. If you feel these may be out of hand then measure them and make a calculated decision from there. Taking shots in the dark based on a feeling is an expensive way to R&D your trucks setup.
 
zfaylor said:
Without measuring primary boost and drive pressure you are just taking shots in the dark. If you feel these may be out of hand then measure them and make a calculated decision from there. Taking shots in the dark based on a feeling is an expensive way to R&D your trucks setup.
Click to expand...

I measure both primary boost and overall boost.

Essentially all I'm saying is that I feel there has to be a better turbo option for my secondary than this 62/65, especially with the upgraded technology in the SXE. So what would you guys run if it was your setup.
 
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chad256 said:
I am mainly only concerned with my drive pressure when spraying nitrous. My current external gate opens once drive pressure exceeds boost pressure. I am leery to dump the e gate into the hot pipe in fear of over-spinning the 480.

I just feel like the truck could benefit from going to a little bigger secondary, Maybe the 64.5/68 would be a good option? I may also upgrade to a 483 or larger and some point in the future.

The truck is fun the way it spools and drives currently, but at this point i'm looking for more on the top end
Click to expand...



Run the 80 harder. The harder you drive a turbo the happier they are
 
chad256 said:
I measure both primary boost and overall boost.

Essentially all I'm saying is that I feel there has to be a better turbo option for my secondary than this 62/65, especially with the upgraded technology in the SXE. So what would you guys run if it was your setup.
Click to expand...

What is your primary boost, overall boost, and drive pressure at full tilt on fuel and what are those numbers when you spray? What is your goal with the truck? Power? Track times? Push the chargers to their limit?

The SX-E isn't the be all end all in turbochargers. They added a 360 thrust, made the wheels shiny, and made a change to one of the turbines. You'll notice the threads about how much of a game changer it is have died down.

I am sure there is a better option than what you are running but until you put some numbers to it you are only guessing.
 
zfaylor said:
The SX-E isn't the be all end all in turbochargers. They added a 360 thrust, made the wheels shiny, and made a change to one of the turbines. You'll notice the threads about how much of a game changer it is have died down.

I am sure there is a better option than what you are running but until you put some numbers to it you are only guessing.
Click to expand...

I just swapped my S366 cover and wheel for the new style. The FMW is 5 Grams heavier, but it is the exact same design. The cover design is decently a improvement, but the only advantage of getting the new SX-E is my option is for the unclipped turbine wheel.
 
What's your truck make for power now? What is primary boost and overall boost?

You really need to hook up a drive pressure gauge before you go changing anything if you want to make informed decisions.




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I appreciate all the responses!
So currently the truck is around 730 on fuel, and I've sprayed a small shot to get it to around 840.
It's been a while since I checked, but on fuel only, overall boost is approx 78psi , with a P.R. if 6.31
Primary is about 35 psi with a P.R. of 3.38
So my secondary is at a 1.87 P.R. Which puts it around 13psi. Which really isn't working it too hard.
I have no numbers while spraying, but I know my boost does creep a little into the 80s.

My goal is to keep progressing. If everything works as it should with no failures, it should break into the 10.9x range or atleast right there with my current setup, considering that my last full pass had a terrible 60ft but the 1/8th mph at 101 and 1/4 mph at 124.4 are in line with many other trucks in that E.T. range.

This setup has been on the truck for two years and I'm kinda looking to change it up a bit. Would also like to get to 800 fuel only.
 
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Tighten up that e-gate to start and make that secondary work a little more.

What housing and turbine does the 80 have?

Making both chargers work a little harder would get you to that 800 mark. If that means plumbing the e-gate to the hot pipe and tightening it up a bit to make the secondary work harder as well then you can always run a second gate to atmosphere gated on overall boost for when you spray.

Which gate are you running right now?

You will need some drive pressure readings to see if you can push that secondary as well. If all of the above is going to push it too hard then obviously it is time to up the secondary but if you are still in a safe zone then push them both more. Whatever you do make a baby step. Making far too large of a jump on the secondary won't necessarily help those 60 times you are after.
 
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666a4eb8e2cf3efa86fa8141a5c85a34.jpg


Sounds like our setups are close, except I'm 24v with a p7100. That was a week ago, you should have a 10 in it.

I would try to drive the 80 harder on fuel. My 80 is only make 25 psi, so I probably have more to gain when I get the 64 gated right but I'd say you should still see a gain in power as well if you get it making 40-45.


Sent from my iPhone using Tapatalk
 
mathews8pt said:
666a4eb8e2cf3efa86fa8141a5c85a34.jpg


Sounds like our setups are close, except I'm 24v with a p7100. That was a week ago, you should have a 10 in it.

I would try to drive the 80 harder on fuel. My 80 is only make 25 psi, so I probably have more to gain when I get the 64 gated right but I'd say you should still see a gain in power as well if you get it making 40-45.


Sent from my iPhone using Tapatalk
Click to expand...

My 480 might already be making 40 or so. I know it's right in that range somewhere. What are the specs on your 64?
 
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