Is too much boost bad?
- Thread starter TURBOV6
- Start date
BLACK6PACK
1 sec reaction King
- Joined
- May 24, 2001
Its not so much boost as detonation. There are guys down here running 35-40 lbs of boost, but they tune for 0 detonation/KR. You also have to take into consideration the turbo's efficiency range. For example, the stock turbo is out of its range at around 22 lbs.
It's not so much as boost that does it, it's cylinder pressure. Remember that boost is air that did not get into the cylinders. If you have ported heads, bigger cam, etc, then 19psi of registered boost could be equivalent to 28psi of registered boost if you only had stock heads, stock cam, etc..
Doug J runs 25+ with ported heads, 206 cam, etc, and plans to turn the wick up a bit..
It doesn't look like you have a differnet cam or ported heads so I doubt that 26psi is going to hurt anything with your combo.
Detonation creates WAY MORE cylinder pressure than just adding boost.
ks
Doug J runs 25+ with ported heads, 206 cam, etc, and plans to turn the wick up a bit..
It doesn't look like you have a differnet cam or ported heads so I doubt that 26psi is going to hurt anything with your combo.
Detonation creates WAY MORE cylinder pressure than just adding boost.
ks
Right on kevin, cylinder pressure will do it every time. Had a buddy blow 2 gaskets in one week on nos and only 18 psi, he kept wondering why he was blowing gaskets on only 18 psi. NOT THE PROBLEM.
But black 6 pack, what cars are you talking about running 35 to 40 psi?
Are you refering to buicks? Good lord, that is one strong crank for that boost spankin if it is a buick. I know duttweiler has two set ups on his stage 2 but I never heard what happened to his 40 psi set up.
On the stock block and head gaskets you can actually crank out alot of boost due to the factories ability to torque down the heads at once more equally than one person can. But I o ringed mine due to having the stock block and heads. Should take around 28 if well tuned and more if you have guts, time, and money to see what will happen.
But black 6 pack, what cars are you talking about running 35 to 40 psi?
Are you refering to buicks? Good lord, that is one strong crank for that boost spankin if it is a buick. I know duttweiler has two set ups on his stage 2 but I never heard what happened to his 40 psi set up.
On the stock block and head gaskets you can actually crank out alot of boost due to the factories ability to torque down the heads at once more equally than one person can. But I o ringed mine due to having the stock block and heads. Should take around 28 if well tuned and more if you have guts, time, and money to see what will happen.
BLACK6PACK
1 sec reaction King
- Joined
- May 24, 2001
www.harpersracing.com
Look about 1/2 way down the page, and you will see the buildup of Orlandos car and the times he was running with a certain amount of boost. Orlando starts at 35lbs and works his way up.
Look about 1/2 way down the page, and you will see the buildup of Orlandos car and the times he was running with a certain amount of boost. Orlando starts at 35lbs and works his way up.
Now thats a guy with time, knowledge, and guts!!
Only lunched a rocker, while running lean on 009's and a 7th injector. Am I missing something here, I thought that the 7th injector was worth no more than 3 tenths regardless of injector size due to unequal distribution in the intake? So he should of been maxed out at high 10's with that fuel system?
But he's only doing low 10's on 38 psi. He should definetly be crankin out 9's, but regardless, he has a stock block doing low 10's on 38 psi, he's the man.
So looks like the factory head gaskets can take a beating huh?
He proved it!
Only lunched a rocker, while running lean on 009's and a 7th injector. Am I missing something here, I thought that the 7th injector was worth no more than 3 tenths regardless of injector size due to unequal distribution in the intake? So he should of been maxed out at high 10's with that fuel system?
But he's only doing low 10's on 38 psi. He should definetly be crankin out 9's, but regardless, he has a stock block doing low 10's on 38 psi, he's the man.
So looks like the factory head gaskets can take a beating huh?
He proved it!
Carolinaturbot6
Pride. Freedom. America
- Joined
- May 24, 2001
TurboV6, how much fuel pressure are you running at 24-26psi? I was under the impression that the stock intercooler wouldn't cool the air charge enough at those boost levels. I thought detonation would occur because of this??
I know that the cure for detonation is having enough octane to go along with the amount of air flowing through the heads. If I'm confused please learn me something. I want to understand this a little more. Thanks.
I know that the cure for detonation is having enough octane to go along with the amount of air flowing through the heads. If I'm confused please learn me something. I want to understand this a little more. Thanks.
Carolinaturbot6,
According to the research that Red Armstrong did the stock IC starts losing it's efficiency at 21psi. However the concensous that I have found on the BB that 26 psi is the max where people start noticing a large difference in ET.
This info I have posted before and it may still be in the archives.
ks
According to the research that Red Armstrong did the stock IC starts losing it's efficiency at 21psi. However the concensous that I have found on the BB that 26 psi is the max where people start noticing a large difference in ET.
This info I have posted before and it may still be in the archives.
ks
Carolinaturbot6
Pride. Freedom. America
- Joined
- May 24, 2001
Thanks Kevin. I always figured a fellow Husker fan was smarter than most.
Giddy Up!
I found my notes!!
I received some info from Red Armstrong a while ago when I bought some chips from him. I hope that he doesn't mind but I though this would be great archive info.
This compares the Stock IC to his Stretched/large neck, stock IC. This info could be up to 10 years old.
Description:
100% of stock and 70% of another and big neck.
He says that it is worth approx. 5mph and 3/10's in the 1/4 mile.
Stock IC: Pressure drop across a stock IC at 20 psi at the intake manifold is approx. 4 1/2 psi. In other words the turbo has to make 24 1/2 psi of boost to get 20 psi at the manifold.
Stretched IC (big neck):
Pressure drop across stretched IC at 20 psi at the intake manifold is approx. 1 1/4 psi. In other words the turbo has to make 21 1/4 psi of boost to get 20 psi at the manifold.
quote: "I found that for each additional pound of boost the turbo charger had to make, the air temperature was incresed 12 to 15 degrees F. My intercooler has 70% more cooling cabability than a stock intercooler, this coupled with the fact that there is less pressure drop across it, means that the turbo doesn't have to make as much boost, reducing the air temperature from the turbocharger..."
Thanks Red Armstrong.
KS
I found my notes!!
I received some info from Red Armstrong a while ago when I bought some chips from him. I hope that he doesn't mind but I though this would be great archive info.
This compares the Stock IC to his Stretched/large neck, stock IC. This info could be up to 10 years old.
Description:
100% of stock and 70% of another and big neck.
He says that it is worth approx. 5mph and 3/10's in the 1/4 mile.
Stock IC: Pressure drop across a stock IC at 20 psi at the intake manifold is approx. 4 1/2 psi. In other words the turbo has to make 24 1/2 psi of boost to get 20 psi at the manifold.
Stretched IC (big neck):
Pressure drop across stretched IC at 20 psi at the intake manifold is approx. 1 1/4 psi. In other words the turbo has to make 21 1/4 psi of boost to get 20 psi at the manifold.
quote: "I found that for each additional pound of boost the turbo charger had to make, the air temperature was incresed 12 to 15 degrees F. My intercooler has 70% more cooling cabability than a stock intercooler, this coupled with the fact that there is less pressure drop across it, means that the turbo doesn't have to make as much boost, reducing the air temperature from the turbocharger..."
Thanks Red Armstrong.
KS
Originally posted by Carolinaturbot6
TurboV6, how much fuel pressure are you running at 24-26psi? I was under the impression that the stock intercooler wouldn't cool the air charge enough at those boost levels. I thought detonation would occur because of this??
I know that the cure for detonation is having enough octane to go along with the amount of air flowing through the heads. If I'm confused please learn me something. I want to understand this a little more. Thanks.
Fuel pressure is around 47lbs (line off) and with Unical 110 leaded, 0'2 is right around 790-800's.
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