Hypothetical Small Turbo VS Larger

[Mike T]

My book sounds like a smart ass and that wasn't what I meant for it to sound like

 

[turbo89]

I have always found your advise to be solid and consider you one of my top 5 sources of info on here.

The way my question was worded it completely eliminated spool up, charge temp and drive pressures in order to compare apples to oranges for lack of a better way to put it. Eliminating those factors 20 pounds is 20 pounds in my book so how would the motor perform any better.

the larger turbo will be quicker and faster to the finish line .. Period

This is applying what you outlined as the points in your scenario

is 20 Psi in a bike tire equal to 20 psi in a tractor tire ?

 

[Mike T]

the larger turbo will be quicker and faster to the finish line .. Period

This is applying what you outlined as the points in your scenario

is 20 Psi in a bike tire equal to 20 psi in a tractor tire ?

Obviously volume and PSI are two different measurements was just trying to keep it simple.

 

[turbo89]

Obviously volume and PSI are two different measurements was just trying to keep it simple.

you said 20 psi across the board from start to finish ...60 vs 70 .. volume plays into it

 

[Mike T]

Honestly I was considering a 6766 since a lot of guys say they are tried and true performers. After running the car at the track I started to question how much difference could there really be between the two if leaving at similar boost pressure. Maybe a little quicker spool for 100 feet?

 

[Mike T]

you said 20 psi across the board from start to finish ...60 vs 70 .. volume plays into it

Since boost is restriction would we need to see RPM increase for volume to increase?

 

[turbo89]

Honestly I was considering a 6766 since a lot of guys say they are tried and true performers. After running the car at the track I started to question how much difference could there really be between the two if leaving at similar boost pressure. Maybe a little quicker spool for 100 feet?

in your scenario .. 60 vs 70 both @ 20 psi = huge

 

[Mike T]

Before we carry on.....Thank you guys for engaging in this unusual discussion. It's been boring as heck around here

 

[turbo89]

Before we carry on.....Thank you guys for engaging in this unusual discussion. It's been boring as heck around here

I can give you an example ... H3 compressor @ 17 psi and a 68-1 @ 17 psi was 17 mph difference

 

[Mike T]

in your scenario .. 60 vs 70 both @ 20 psi = huge

I'm not good with formulas but I believe that two compressors blowing into the atmosphere would have different volumes but blowing through a restriction at the same psi would yield the same volume.

 

[turbo89]

I'm not good with formulas but I believe that two compressors blowing into the atmosphere would have different volumes but blowing through a restriction at the same psi would yield the same volume.

leave the formulas for scientists .. try it on a car and then report back

 

[Mike T]

I can give you an example ... H3 compressor @ 17 psi and a 68-1 @ 17 psi was 17 mph difference

I may come away with a whole new understanding of things but in your example do you think this difference is because of the 3 basic things that we have said makes the newer turbos better.

 

[salvageV6]

Yep.

Stock motor car, my PTE51 at 24 psi. was within 20HP of my DBB70 p-trim same boost, 155K miles on it 425RWHP with the 70 working on the wrong side of the curve.

Similar weather different days, actually different year, but everything else on the car was the same pump gas and alky. 23* timing in 3rd, locked 3200 stall Protorque converter.

You have much fancier parts, maybe that makes a difference.

Keep your turbo until Bison tells you it's maxed out.

I liked the DBB70 more because it cost 3X as much and sounded like a 747 taking off when spooling, oh and the purple annodized side cover, maybe you should get a new turbo....

Not a gooroo though but I do drive around a lot in a 31 year old car and stayed at a Holiday Inn Express once.

 

[Mr.Spool]

My book sounds like a smart ass and that wasn't what I meant for it to sound like

i like a good smart ass

 

[Mr.Spool]

I have always found your advise to be solid and consider you one of my top 5 sources of info on here.

thanks,but i get where your coming from mow just reread that question again.20psi is 20psi you are correct in your fantasy question

 

[Mr.Spool]

two compressors blowing into the atmosphere would have different volumes but blowing through a restriction at the same psi would yield the same volume.

i have seen that multiple times.all the combos i have seen only run faster with lower boost if they have better air pumps.if not they only go faster if they increase the boost number.

 

[TurboTnZ06]

If you don't do anything else, if the small turbo combo was correct for the combo, the bigger turbo will be slower because it'll need more converter/tuning to spool up. Take a stock GN/T and put a TE44 on it, it'll be a dog on the street compared to the stocker.

 

[Mike T]

thanks,but i get where your coming from mow just reread that question again.20psi is 20psi you are correct in your fantasy question

For the most part it is unrealistic. For a long time now I've been reading post that aren't technically correct if we look deep into the basics.

 

[Mr.Spool]

For the most part it is unrealistic. For a long time now I've been reading post that aren't technically correct if we look deep into the basics.

its also the way it was posed,your question mimics a nitrous car which has a much higher power average throughout a run.

 

[Mike T]

This is the 70Q a few weeks ago. The wastegate solenoid was set to cycle @ 15 psi on launch. The ptc converter is stalling to 4200 @15 psi. This is the 5th pass on this motor and I was just looking to get into the 11's that night.
It went 10.88 @ 125