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Discussion Starter #1
I went to the track this past weekend.It was in 80's with high humidity.The intake air temps were reaching 185*.
My question is,,,,at what IAT will the power be effected and start falling off??
AFR was 13 @ wot.I have a 1071 BDS roots and after a few passes I increased the boost from 6 to 8 to 10 and the MPH only increased 3 MPH:confused:
I have been 9.3 @ 146 with 6 lbs through the 4 inch exhaust and it was choking with reversion.This weekend I uncapped the dumpers and hoped the crack the 8's but couldn't get faster than 9.6 with 10 lbs of boost. That was 28* timing and 13 @ wot.
Engine is a 545 2nd gen hemi with fueler aluminum heads.

I was rather disappointed!:smt093
 

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3-4 tenths vs. a cool low humidity good weather day pretty easy if it
will take the extra power.
 

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May be just a combination of parts not working well together. You didn't say which fuel heads, but suspect ports are pretty good size for what your doing. Just my thoughts.
 

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Discussion Starter #10
about 20* short on both, can't imagine it's going to do well.
Car is street driven over 1000 miles a season. If I can get to the track 4 or 5 times a year I'm happy. Have the valve covers off to leak it & do a compression test.
If I had that 20* would it still survive through the tailpipes?
 

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about 20* short on both, can't imagine it's going to do well.
With the Fuel heads it's already hurting for street use. Motors just not gonna be happy.
 

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Discussion Starter #12
With the Fuel heads it's already hurting for street use. Motors just not gonna be happy.
I am quite happy with the street manors,I was disappointed with my last trip to the track.The heat and humidity was high,the N/A guys were of 3 tenths and I couldn't get over 140 MPH when I should have cracked 150.
I'm going over to the garage and leak it down and do a compression test. Imight even take the springs off and see if they are going soft on me.........
I just have to think it was the weather as it has gone 146 MPH throught the tail pipes.

https://www.facebook.com/dan.tomchik/videos/10212759128164427/
 

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Why is your total timing at WOT only 13 degrees? Seems very low to me. Afr would be quite a bit richer too if it was mine.
 

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Cool Car sir......thanks for the vid.

I would not overthink it until you get to run on a decent weather day.
I have seen air temp and humidity kill some substantial power
on my boosted cars.......more so than NA applications IMO.
 

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I am quite happy with the street manors,I was disappointed with my last trip to the track.The heat and humidity was high,the N/A guys were of 3 tenths and I couldn't get over 140 MPH when I should have cracked 150.
I'm going over to the garage and leak it down and do a compression test. Imight even take the springs off and see if they are going soft on me.........
I just have to think it was the weather as it has gone 146 MPH throught the tail pipes.

https://www.facebook.com/dan.tomchik/videos/10212759128164427/
Didn't mean to sound disrespectful, should have choose some different words. Those heads were designed for wide open throttle with 60 psi boost going through them. Glad there working for you have fun.
 

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Discussion Starter #18
Didn't mean to sound disrespectful, should have choose some different words. Those heads were designed for wide open throttle with 60 psi boost going through them. Glad there working for you have fun.
No problem Ron,I respect all that you say. The way I read your statement at the boost levels I am working with I'm not producing the velocity to benefit from the large ports.
These heads were sitting in my garage for over 20 years before I was urged to "bring them over".I had not used then due to the raised port thinking I would need new headers fabbed up. Joe was able to port the roof of the exhaust flange to match the top of the head port so we used them.They might not be the best but they are better than the stock virgin iron heads I had been using!
 

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The math says that air density changes about 2% for every 10 degree F.
This^^
Whether or not your time slips reflect your engine performance perfectly, higher intake air temps always lowers engine power, all else being held equal. You added 67% more boost but jacked up intake temps somewhere around +30F over the 6psi level at the same time which reduced the net power gain.



Hpwizard.com/engine-horsepower-calculator.html
 

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Discussion Starter #20
This^^
Whether or not your time slips reflect your engine performance perfectly, higher intake air temps always lowers engine power, all else being held equal. You added 67% more boost but jacked up intake temps somewhere around +30F over the 6psi level at the same time which reduced the net power gain.



Hpwizard.com/engine-horsepower-calculator.html
Thanks guys for your input.Started pulling the engine out,,,SUM-TING-WONG:-damnit
 
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