What HP at what PSI?
#22
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I am going to dissent here a little bit.
If the question is - "for the most part, what approximate horsepower have people seen on a dyno at 7psi using a t28 turbo?" I think that question can be answered, especially if you give exactly what variation of a T28 turbo you are talking about and some other variables.
It is my understanding that T28 can be anything from a GT2554 to a 2560, and 7psi on those two turbos is a bit different, or am I mistaken?
Here is the thing though, the culture of MT.net is not to ask questions that can be found with a little digging. Also, if you are running a megasquirt, Doing a 1:1 pull (4th gear on a 5 speed, 5th gear on a 6 speed) over a relatively flat piece of road will give you a better ballpark than we can on the net.
If the question is - "for the most part, what approximate horsepower have people seen on a dyno at 7psi using a t28 turbo?" I think that question can be answered, especially if you give exactly what variation of a T28 turbo you are talking about and some other variables.
It is my understanding that T28 can be anything from a GT2554 to a 2560, and 7psi on those two turbos is a bit different, or am I mistaken?
Here is the thing though, the culture of MT.net is not to ask questions that can be found with a little digging. Also, if you are running a megasquirt, Doing a 1:1 pull (4th gear on a 5 speed, 5th gear on a 6 speed) over a relatively flat piece of road will give you a better ballpark than we can on the net.
That is my question.
Good shout on the turbo. It's a gt2560r from an s15.
Thanks for that. I know I could dig, I did a bit, I thought it might be nice to have a good few hp and specs in the one post. Also, I am at work and just wanted some quick answers.
Apparently that's an awful idea.
Thanks tho. Appreciate it.
#26
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I got way to guess WHP at any boost level is Pressure Ratio multiplied by Stock WHP.
Assuming 110 whp stock 1.8.
7 psi = ((7 +14.6)/14.6) * 110 whp = 1.48 * 110 whp = 165 WHP
10 psi = ((10 +14.6)/14.6) * 110 whp = 1.68 * 110 whp =185 WHP
14.6 psi = ((14.6+14.6)/14.6) * 110 whp = 2.00 * 110 whp =220 WHP
This assume no temperature change in IAT vs Turbocharged so it will be more accurate with better intercooling. This formula would also be a good estimate for other size engine with different NA HP
This also proves the 7whp per psi estimate (but with a 200whp base engine it would be a different whp gaine per psi)
1 psi = ((1 /14.6) * 110 whp = 0.07 * 110 whp = 7.7 WHP Gain per PSI
Assuming 110 whp stock 1.8.
7 psi = ((7 +14.6)/14.6) * 110 whp = 1.48 * 110 whp = 165 WHP
10 psi = ((10 +14.6)/14.6) * 110 whp = 1.68 * 110 whp =185 WHP
14.6 psi = ((14.6+14.6)/14.6) * 110 whp = 2.00 * 110 whp =220 WHP
This assume no temperature change in IAT vs Turbocharged so it will be more accurate with better intercooling. This formula would also be a good estimate for other size engine with different NA HP
This also proves the 7whp per psi estimate (but with a 200whp base engine it would be a different whp gaine per psi)
1 psi = ((1 /14.6) * 110 whp = 0.07 * 110 whp = 7.7 WHP Gain per PSI
Last edited by cyotani; 06-29-2016 at 11:52 AM.
#31
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I got way to guess WHP at any boost level is Pressure Ratio multiplied by Stock WHP.
Assuming 110 whp stock 1.8.
7 psi = ((7 +14.6)/14.6) * 110 whp = 1.48 * 110 whp = 165 WHP
10 psi = ((10 +14.6)/14.6) * 110 whp = 1.68 * 110 whp =185 WHP
14.6 psi = ((14.6+14.6)/14.6) * 110 whp = 2.00 * 110 whp =220 WHP
This assume no temperature change in IAT vs Turbocharged so it will be more accurate with better intercooling. This formula would also be a good estimate for other size engine with different NA HP
This also proves the 7whp per psi estimate (but with a 200whp base engine it would be a different whp gaine per psi)
1 psi = ((1 /14.6) * 110 whp = 0.07 * 110 whp = 7.7 WHP Gain per PSI
Assuming 110 whp stock 1.8.
7 psi = ((7 +14.6)/14.6) * 110 whp = 1.48 * 110 whp = 165 WHP
10 psi = ((10 +14.6)/14.6) * 110 whp = 1.68 * 110 whp =185 WHP
14.6 psi = ((14.6+14.6)/14.6) * 110 whp = 2.00 * 110 whp =220 WHP
This assume no temperature change in IAT vs Turbocharged so it will be more accurate with better intercooling. This formula would also be a good estimate for other size engine with different NA HP
This also proves the 7whp per psi estimate (but with a 200whp base engine it would be a different whp gaine per psi)
1 psi = ((1 /14.6) * 110 whp = 0.07 * 110 whp = 7.7 WHP Gain per PSI
On sunday I went to the dyno with Ed. He has a gt2871. I have a td04-15g. I made like 160ft/lbs at 8psi. He made like 200 something.
You can look at compressor maps. Calculate the pressure ratio and see what the compressor flows at that ratio. It isn't exact but it gives you an idea.