9 Sec Turbo Setup?

[Digital]

Nice explanation of what somebody was trying to say early on in this thread, although didn't know the techno-speak to state it formally. Hmmm... now who was that? :shrug:

No one was ever questioning this. No one said that you can add a 600hp rated turbo and get 600hp.

All that was said was spool time on turbos that we know will get you X hp on a setup at different sizes.
We know just like with eaton pulley sizes certain turbos will net certain hp gains. It's not rocket science.


Seems like some people can't read I guess and try to make points where there was none to be made.

 

[2bscrewed]

Lets say the terminator engine makes 300rwhp stock. The eaton increases that by 75rwhp. Now you put a modest pulley on it and increase that by almost double, 125rwhp. You're making 425rwhp now. That's 425 hp pushing on your exhaust.
Now lets say you have a 76mm turbo, nothing fancy just a regular ol 76. The "peak operating" level of this turbo will give you 600rwhp ADDED hp. and would spool at 3500rpm. So with our setup if we fully utilised this turbo we would have 425+600 for 1025rwhp. Now are we going to be making that? no. We want to make 750. So we have 275 WASTED hp potential.... So why go 76? Lets try another size..
Lets say we use a 67.. Lets say the 67 makes 425 PEAK hp potential and spools at 2500rpm. Now we 425+425 = 850. Now that's much closer to the number we want to be at. And we have dropped 1000 rpm spool time.
Hopefuly that logic makes sense. Now obviously these numbers arent all 100% but they are fairly close, and this is all based upon a compound setup. You would INCREASE the spool time GREATLY the less hp you have to start out with obviously.
As an example the 67 spooling at 2500 would probably change to atleast 4000-4500, but you'd make the same power more or less because of the PEAK potential.

.

No one was ever questioning this. No one said that you can add a 600hp rated turbo and get 600hp.

All that was said was spool time on turbos that we know will get you X hp on a setup at different sizes.
We know just like with eaton pulley sizes certain turbos will net certain hp gains. It's not rocket science.


Seems like some people can't read I guess and try to make points where there was none to be made.

It looks like you were saying you could just add the seperate estimated power of the two power adders here, which is what people are disagreeing with.

 

[Digital]

You can. It's not scientific and doesnt go through loss of pressure or intake of the eaton. It's just a basic estimate that you can use so you don't have to spend an hour explaining to people EXACTLY what's happening.

 

[4sdvenom]

If a basic 76mm turbo supports 850 HP, and you put it to use in a compound set-up with a Terminator motor pullied and making 425 HP on it's own, then the first 425 HP the 76mm turbo can support will be ate up just feeding the 425 HP blower motor, that leaves 425 HP worth of supportable airflow on the table to increase (not accounting for VE losses or parasitic loss from anything). If you use a 67 that can support 600 HP you will still lose the first 425 HP just to feed the 425 HP blower motor, leaving you 175 HP worth of supportable airflow from the turbo. After that you will push the turbo out of its efficiency range and IATs will skyrocket.

Keep in mind, the 425 HP blower only motor still needs 425 HP worth of airflow. With the turbo in the intake tract it is responsible to supply it, which subtracts from it's overall supportable airflow potential.

Ken :beer:

 

[spyder1337]

I'll try to keep this as simple as I can and only in regards to compound set-ups.

The peak horsepower will be completly dependant on the size of the turbo and the amount of CFM it is capable of flowing. This is because the air has to flow through the turbo before it ever gets to the blower. The turbo does not force air through the blower, in actuality the blower is reducing the backpressure at the discharge of the turbo because the blower moves the air from point A (turbo discharge) to point B blower discharge faster than would normally occure without the blower. This in turn makes the turbo more efficient, and is why you see people mention only 5 psi from the turbo, but it's actually moving the same CFM of air through it as it would at a much higher psi without the blower. The compound set-up also makes the blower more efficient because it is grabbing a fixed volume (PD blowers are constant VOLUME machines) of a higher pressure air than if it was drawing it's own air at whatever elevation your at. Think of it like this.....a PD blower only car at sea level is more efficient with the same pulley ratio than the same car at 6000' elevation in Colorado. Why? because there is a higher pressure air available at the inlet of the blower. The compound set-up works in the same manner, just far more exagerated because you can increase the air pressure at the inlet of the blower in measurements of psi verses measurements of hg. The formula (which I'll add later once I find it again) has you figure the PR for the turbo, and the PR for the blower, multiply those together, and convert back to a PSI for the total psi the motor is seeing.

With all that said, I would not put a small single into a compound set-up. Even though the blower makes the turbo more effecient, the turbo still has to spin fast enough to supply the required CFM to make X amount of horsepower, and you will end up pushing the small turbo way past it's efficiency range. They can only spin so fast before the impeller blades lose "traction" with the air and will do nothing but cavitate and heat the air up! For a single turbo in a compound set-up I wouldn't consider anything smaller than a 76mm with a good sized A/R exhaust housing. Personally I would look closer at an 88 or a 91mm turbo for a single compound set-up!

Ken:beer:

Also just to add!

(and some of you can go ahead and flame all you want, but I've researched this far more than most)

You can not add the power output of the blower to the power output of a turbo and get a total power output. Just as you would not take a 500 hp N/A motor and add an 800 hp turbo and expect to get 1300 hp. Ultimately the turbo is the limiting factor in how much HP can be done in a compound set-up (or turbo only for that matter), since it has to flow the air required for XXX amount of horsepower. The blower is just moving that air from point A to point B which is why it is not a restriction. Some extra power will be gained through the efficiency at which the turbo will be at, but it has to flow X CFM to make XXX amount of HP, and the impeller will spin the same speed to move that CFM of air regardless of what the boost pressure at the discharge is.....it's just doing it alot easier with less back pressure in a compound set-up. The impeller speed of the turbo is a constant to the CFM it's moving, and not constant to the psi at it's discharge!

Ken

If a basic 76mm turbo supports 850 HP, and you put it to use in a compound set-up with a Terminator motor pullied and making 425 HP on it's own, then the first 425 HP the 76mm turbo can support will be ate up just feeding the 425 HP blower motor, that leaves 425 HP worth of supportable airflow on the table to increase (not accounting for VE losses or parasitic loss from anything). If you use a 67 that can support 600 HP you will still lose the first 425 HP just to feed the 425 HP blower motor, leaving you 175 HP worth of supportable airflow from the turbo. After that you will push the turbo out of its efficiency range and IATs will skyrocket.

Keep in mind, the 425 HP blower only motor still needs 425 HP worth of airflow. With the turbo in the intake tract it is responsible to supply it, which subtracts from it's overall supportable airflow potential.

Ken :beer:

This is the info people need to read and go by rather than the digital guys misinformation.

 

[YGETV8]

No one was ever questioning this. No one said that you can add a 600hp rated turbo and get 600hp.

All that was said was spool time on turbos that we know will get you X hp on a setup at different sizes.
We know just like with eaton pulley sizes certain turbos will net certain hp gains. It's not rocket science.


Seems like some people can't read I guess and try to make points where there was none to be made.

I'm gonna go out on a limb and say that if ALL us "second graders" that "can't read" didn't understand what you were trying to say, then you must not have done a very good job explaining it.

 

[Digital]

Ken as always good info.

Explain to me how what he said was different then what I said? Sept he took the time to spoon feed everything in extreme detail.

 

[2bscrewed]

Ken as always good info.

Explain to me how what he said was different then what I said? Sept he took the time to spoon feed everything in extreme detail.

So you don't see a difference from what he said here:

If a basic 76mm turbo supports 850 HP, and you put it to use in a compound set-up with a Terminator motor pullied and making 425 HP on it's own, then the first 425 HP the 76mm turbo can support will be ate up just feeding the 425 HP blower motor, that leaves 425 HP worth of supportable airflow on the table to increase (not accounting for VE losses or parasitic loss from anything). If you use a 67 that can support 600 HP you will still lose the first 425 HP just to feed the 425 HP blower motor, leaving you 175 HP worth of supportable airflow from the turbo. After that you will push the turbo out of its efficiency range and IATs will skyrocket.

Keep in mind, the 425 HP blower only motor still needs 425 HP worth of airflow. With the turbo in the intake tract it is responsible to supply it, which subtracts from it's overall supportable airflow potential.

Ken :beer:

To what you said here?

Lets say the terminator engine makes 300rwhp stock. The eaton increases that by 75rwhp. Now you put a modest pulley on it and increase that by almost double, 125rwhp. You're making 425rwhp now. That's 425 hp pushing on your exhaust.
Now lets say you have a 76mm turbo, nothing fancy just a regular ol 76. The "peak operating" level of this turbo will give you 600rwhp ADDED hp. and would spool at 3500rpm. So with our setup if we fully utilised this turbo we would have 425+600 for 1025rwhp. Now are we going to be making that? no. We want to make 750. So we have 275 WASTED hp potential.... So why go 76? Lets try another size..
Lets say we use a 67.. Lets say the 67 makes 425 PEAK hp potential and spools at 2500rpm. Now we 425+425 = 850. Now that's much closer to the number we want to be at. And we have dropped 1000 rpm spool time.
Hopefuly that logic makes sense. Now obviously these numbers arent all 100% but they are fairly close, and this is all based upon a compound setup. You would INCREASE the spool time GREATLY the less hp you have to start out with obviously.
As an example the 67 spooling at 2500 would probably change to atleast 4000-4500, but you'd make the same power more or less because of the PEAK potential.

.

 

[YGETV8]

Digital: You state right in the quote above "425+600 for 1025rwhp" and "425+425=850" referring to the turbo ratings added to the Eaton output. You say nothing about the max hp being limited to the turbo "peak operating level"... or can I still not read? Guess I better go back and tell the college that gave me my degree I want my money back.

 

[Digital]

I never said anything about the turbos rating. That's where you miss read. I already did the calculation for you in the post. I don't know any mid-60mm turbos that have a rating of 425hp. Do you?

 

[spyder1337]

From what I read in this thread the 6x mm is around 600 hp supportable, not 425. Also, the biggest flaw is assuming that a car making 425 on an eaton and then adding a turbo that is capable of supporting 800 will be 425 + 800 = max power, this is far from correct. It's already been explained in detail in this thread, you have yet to dyno your compound setup, correct? All this is speculation on your part, dyno your setup and post results. Not trying to be a dick but I don't know what you're reading or if you're just making this shit up off the top of your head, either way it's incorrect.

 

[Digital]

Mines rated at 800 and it isnt anything special.