Power loss with a ported intake manifold
Power loss with a ported intake manifold I put on a ported intake manifold and 58mm throttle body, and I decided to dyno again to see if it helped. Well to make it short, I lost 9rwhp. 
I'm thinking it might be just the 2 different dyno's reading different, and me having 18psi in my dr's vs 30 on street tires might make a difference, but I wouldn't think I would loose power. On one bank, the ports are matched with the gaskets perfectly, but on the other side, they are all 1/8-1/4" lower than the gaskets/head ports. So I'm thinking that ridge that the air is hitting going from the manifold to the head port might be causing turbulance and a power loss. How much power would that cost me, if any? 
Or should I just not worry about it?
Before
http://www.lifeinwidescreen.com/siihp/gm846 tuned.jpg
After
http://www.lifeinwidescreen.com/siihp/dyno_spray.jpg
I'm thinking it might be just the 2 different dyno's reading different, and me having 18psi in my dr's vs 30 on street tires might make a difference, but I wouldn't think I would loose power. On one bank, the ports are matched with the gaskets perfectly, but on the other side, they are all 1/8-1/4" lower than the gaskets/head ports. So I'm thinking that ridge that the air is hitting going from the manifold to the head port might be causing turbulance and a power loss. How much power would that cost me, if any? Or should I just not worry about it? Before
http://www.lifeinwidescreen.com/siihp/gm846 tuned.jpg
After
http://www.lifeinwidescreen.com/siihp/dyno_spray.jpg
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From: king of prussia, pa (home) and williamsport, pa (school)
where did you get your ported intake manifold?
i see these on ebay and wondering if i should do this with a stock ported TB ... hopefully pick up a few horsepower. .. take a look
http://cgi.ebay.com/ebaymotors/Fully...spagenameZWDVW
i see these on ebay and wondering if i should do this with a stock ported TB ... hopefully pick up a few horsepower. .. take a look
http://cgi.ebay.com/ebaymotors/Fully...spagenameZWDVW
how do you know the ports aren't lined up with the gaskets????? Cuz you can't see in there once the thing is bolted up....
But if you are sure that's the case YES that will cost you power..... air velocity slowed down, turbulence in the port..... that bank will probably run richer as well since it's getting less air (in a combustion cycle due to turbulence) and the same amount of fuel...
But if you are sure that's the case YES that will cost you power..... air velocity slowed down, turbulence in the port..... that bank will probably run richer as well since it's getting less air (in a combustion cycle due to turbulence) and the same amount of fuel...
Originally Posted by speed_demon24
I put on a ported intake manifold and 58mm throttle body, and I decided to dyno again to see if it helped. Well to make it short, I lost 9rwhp. I'm thinking it might be just the 2 different dyno's reading different, and me having 18psi in my dr's vs 30 on street tires might make a difference, but I wouldn't think I would loose power. On one bank, the ports are matched with the gaskets perfectly, but on the other side, they are all 1/8-1/4" lower than the gaskets/head ports. So I'm thinking that ridge that the air is hitting going from the manifold to the head port might be causing turbulance and a power loss. How much power would that cost me, if any? Or should I just not worry about it?
Before
http://www.lifeinwidescreen.com/siihp/gm846 tuned.jpg
After
http://www.lifeinwidescreen.com/siihp/dyno_spray.jpg
I'm thinking it might be just the 2 different dyno's reading different, and me having 18psi in my dr's vs 30 on street tires might make a difference, but I wouldn't think I would loose power. On one bank, the ports are matched with the gaskets perfectly, but on the other side, they are all 1/8-1/4" lower than the gaskets/head ports. So I'm thinking that ridge that the air is hitting going from the manifold to the head port might be causing turbulance and a power loss. How much power would that cost me, if any? Or should I just not worry about it? Before
http://www.lifeinwidescreen.com/siihp/gm846 tuned.jpg
After
http://www.lifeinwidescreen.com/siihp/dyno_spray.jpg
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Originally Posted by NoMoreLS1
Different days... different temps, different humidity, different wheels, different dynos (shouldn't be much of a difference, but no two dynos will be exactly the same). Add all of those differences and your loss is possible. Was the car tuned after these upgrades? If you knew about the gaskets not lining up... why did you install it?
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Originally Posted by emerica4601
where did you get your ported intake manifold?
i see these on ebay and wondering if i should do this with a stock ported TB ... hopefully pick up a few horsepower. .. take a look
http://cgi.ebay.com/ebaymotors/Fully...spagenameZWDVW
i see these on ebay and wondering if i should do this with a stock ported TB ... hopefully pick up a few horsepower. .. take a look
http://cgi.ebay.com/ebaymotors/Fully...spagenameZWDVW
air is very finicky within a port, hence the reason you can gain considerable amount's by just "cleaning" up the port's and what not.. I'd def. have that issue resolved.. As far as how much power you lost.. 9rwhp on a diff dyno is not uncommon.. If your going to dyno your car i'd suggest using the same dyno so you can keep track of your result's a lil more accurately...
