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Is there a direct relation between a stock engine without any other mods and the amount of boost?

I am wondering why I am seeing different HP values at the same boost level?
Is it only the IAT that explains the great difference of HP beetween cars?

I am pushing 15psi of boost with the TVS with stock pulley and EVO tune.
How much power should I be making?

:thinkerg:
 

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Is there a direct relation between a stock engine without any other mods and the amount of boost?

I am wondering why I am seeing different HP values at the same boost level?
Is it only the IAT that explains the great difference of HP beetween cars?

I am pushing 15psi of boost with the TVS with stock pulley and EVO tune.
How much power should I be making?

:thinkerg:
So the rough relationship between boost and HP is that for every 14 lbs of boost(14 lbs is 1 atmosphere) the power in the engine doubles from a stock engine. However when you have boost there is inefficiency due to heat and parasitic loss. So becuase of the differences in heat levels and parasitic loss from blowers with different characteristics or turbos which eliminate most parasitic loss by using exhaust you see different levels of HP at different levels of boost.
 

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Damn Ricardo I'm jealous of that 15 PSI. All I can manage in So. Nevada is 12 with a custom tune. I talked to several tuners and the most they've seen is 13 from a TVS stock pulley set-up, with the average 11-12. I guess the air in Montreal is better than the surface-of-the-moon thin air down here.
 

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Damn Ricardo I'm jealous of that 15 PSI. All I can manage in So. Nevada is 12 with a custom tune. I talked to several tuners and the most they've seen is 13 from a TVS stock pulley set-up, with the average 11-12. I guess the air in Montreal is better than the surface-of-the-moon thin air down here.
I'm don't quite understand why I get 15psi from the stock pulley but I am happy. What's funny is I was getting the usual 8.5-9psi with the stock supercharger. The cold air is doing some magic!
 

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I'm don't quite understand why I get 15psi from the stock pulley but I am happy. What's funny is I was getting the usual 8.5-9psi with the stock supercharger. The cold air is doing some magic!
I also got 15 with my setup from Lightning Force in SE Georgia, and VERY pleased with it!
 

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15 is not bad at all for your setup...i was at once pushing 18, but since recent mods, dialed it down to 15psi. what size "stock" pulley are you referring to on your tvs? 3"? see my sig...those numbers are on a mustangdyno which is lower results than a dynojet
 

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15 is not bad at all for your setup...i was at once pushing 18, but since recent mods, dialed it down to 15psi. what size "stock" pulley are you referring to on your tvs? 3"? see my sig...those numbers are on a mustangdyno which is lower results than a dynojet
I believe the stock pulley is 3 inch.

I have been logging a few PIDs : Load, MAF and Spark

What I noticed is that the MAF seems to never go higher than 934.078. Is it possible that it is pegging at this level and not at 1024?

Also the Load is at 1.957. It looks very high to me for 15psi of boost.

The tune is removing 3-4 spark advance (from 20-21 to 16-17) when the IAT is getting around 106F. Do you think this is safe?
 
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