LOST BOOST!?

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spoc8hi

New Member

Feb 17, 2008

22

0

0

mobile alabama

Mar 17, 2008

#1

• Mar 17, 2008

• #1

hi guys, i just put a 5.1 stroker in my stang. before the swap, i made 10-12lbs of boost with my vortech v-1, but now the best i can get is 6-7. is this normal because of the increased cobustion area or do i have a boost leak?

 

jstreet0204

Active Member

Jun 26, 2003

939

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36

Winston Salem, NC

Mar 17, 2008

#2

• Mar 17, 2008

• #2

spoc8hi said:

hi guys, i just put a 5.1 stroker in my stang. before the swap, i made 10-12lbs of boost with my vortech v-1, but now the best i can get is 6-7. is this normal because of the increased cobustion area or do i have a boost leak?

Click to expand...

Losing some boost would be normal with more displacement. Boost is just a measure of restriction. Your engine is breathing more so boost goes down. I'm a little surprised it went down that much, but I guess it is possible. 10 down to 7 sounds reasonable. 12 down to 6 sounds like a little much, but I dunno

 

SaleenGT2001

Well-Known Member

Jul 18, 2005

2,811

4

58

Four Oaks NC

Mar 17, 2008

#3

• Mar 17, 2008

• #3

ported heads, cams and LTs will cuase boost drop b/c they allow the engine to flow better

 

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ceracer33

New Member

Aug 30, 2005

118

1

0

Mar 17, 2008

#4

• Mar 17, 2008

• #4

what they said. ur engine is requiring a lot more cfm to make the same boost as before now. if u did ported heads with the swap then i could see u losing a lot of boost like that. u need more cfm.

 

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speedytang

Founding Member

Jul 28, 1999

765

1

17

Marengo,Ohio,US

Mar 18, 2008

#5

• Mar 18, 2008

• #5

Now you need to spin the supercharger harder and yes this is normal that is why they sell Pulleys.

 

ADRENLN

Active Member

Apr 16, 2003

2,342

3

49

NJ

Mar 18, 2008

#6

• Mar 18, 2008

• #6

holy.....i didnt think you would lose that much with a stroker. i am getting a stroker myself and am not prepaired to lose that kind of boost. might have to pulley down.

 

ADRENLN

Active Member

Apr 16, 2003

2,342

3

49

NJ

Mar 18, 2008

#7

• Mar 18, 2008

• #7

honestly yours seems a bit excesive.

 

Green&GoldGT

Member

Aug 1, 2005

302

0

17

Virginia

Mar 18, 2008

#8

• Mar 18, 2008

• #8

I know that extra displacement will lower boost. But isn't extra stroke supposed to increase the speed of the blower?

 

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SilverBullet00

New Member

Jul 5, 2004

1,150

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Wichita, KS

Mar 18, 2008

#9

• Mar 18, 2008

• #9

Just because you loose boost doesnt mean you loose power.

 

jstreet0204

Active Member

Jun 26, 2003

939

0

36

Winston Salem, NC

Mar 18, 2008

#10

• Mar 18, 2008

• #10

SilverBullet00 said:

Just because you loose boost doesnt mean you loose power.

Click to expand...

Exactly! Like I stated earlier, boost is a measure of restriction. If you lose boost because you engine flows more air you have gained power because it isn't working as hard to flow the same cfm.

 

jstreet0204

Active Member

Jun 26, 2003

939

0

36

Winston Salem, NC

Mar 18, 2008

#11

• Mar 18, 2008

• #11

Green&GoldGT said:

I know that extra displacement will lower boost. But isn't extra stroke supposed to increase the speed of the blower?

Click to expand...

Changing the stroke does not change the rpm of the blower.

 

BennyBlown2v

New Member

Dec 9, 2004

1,233

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Carmel, INdiana

Mar 18, 2008

#12

• Mar 18, 2008

• #12

SilverBullet00 said:

Just because you loose boost doesnt mean you loose power.

Click to expand...

heh when I lost boost from my intercooler I lost 20rwhp ...all back now + some though hehe.

 

jstreet0204

Active Member

Jun 26, 2003

939

0

36

Winston Salem, NC

Mar 18, 2008

#13

• Mar 18, 2008

• #13

BennyBlown2v said:

heh when I lost boost from my intercooler I lost 20rwhp ...all back now + some though hehe.

Click to expand...

That's a little different though. Your intercooloer not only cooled the air charge causing a pressure drop, it also created a restriction. The opposite of what we are talking about here.

 

04YELLOWGT

Active Member

Jun 29, 2005

1,135

2

39

Indiana

Mar 18, 2008

#14

• Mar 18, 2008

• #14

I lost 1-2lbs with just headers so I could see that happening.

 

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spoc8hi

New Member

Feb 17, 2008

22

0

0

mobile alabama

Mar 18, 2008

#15

• Mar 18, 2008

• #15

thats a relief. i was afraid i had a serious boost leak somewhere. i guess ill just swap the pulley. thanks for all your help.

 

joshjwc9

Active Member

Jun 12, 2006

1,095

17

39

Palm Harbor, FL

Mar 18, 2008

#16

• Mar 18, 2008

• #16

Now has the car been dynoed? Going from a stock block and bottom end to stroked/forged would do that...

Sounds like the little V1 should be given to me and you should step up to a T or YSi trim