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Husky

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VXII L67 Berlina Wagon and VEIISSV M6 Sportswagon
At the moment I'm in the process of planning an L67 upgrade for my VX, but i keep running into the term "Boost" now someone correct me if I'm wrong, but does boost simply mean the amount of air the supercharger is force feeding the engine? and what about upping boost? Is it simply a matter off changing to a smaller pulley on the SC, in order to increase it's speed in comparison to the speed of the belt?

And what is a good boost upgrade for a stock L67? what do they come out of the factory with?
 

kiwicon

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yes, yes, yes, talk to Raptor - have a look in the sponsors section
 

AirStrike

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Get out of the process of planning a L67 upgrade, waste of money.
Turbo or raptor the standard engine, when/if it dies build one.
 

Decicrate

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With a L67, boost or manifold pressure is a sign of restriction. With the term boost we are talking about how much pressure is in the manifold.
From factory the L67 averages about 6PSI of boost at full noise. Some have a bit more, some a bit less.
When dealing with a Positive displacement blower, spinning it faster by putting a smaller pulley on it will generate you more boost, BUT it will also generate more heat and heat is something you don't want.

You can run a 85mm (10PSI) pulley with no problems on a stock engine with a stock tune. This will give you a little more power and torque.
But from there you have to start making other changes if you want to start to make more power, eg cam, exhaust, intercooler and the list goes on.

If you want something that is a rocket off the line and has great low down torque then a L67 is a great choice.
If you want some thing that doesn't start to make power/torque until about 2800RPM onwards then a Raptor or turbo maybe down your path.

If you are interested in 1/4 mile times, then a L67 or Turbo is the way to go.
 

AirStrike

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If you want something that is a rocket off the line and has great low down torque then a L67 is a great choice.
If you want some thing that doesn't start to make power/torque until about 2800RPM onwards then a Raptor or turbo maybe down your path.
By the same token if you want something to make power without having to sell your first born and left nut don't go a L67.
As for the power delivery, depends on turbo selection as to when it makes power..............you can't make a blanket from 2800rpm onwards claim.
 

Decicrate

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By the same token if you want something to make power without having to sell your first born and left nut don't go a L67.
As for the power delivery, depends on turbo selection as to when it makes power..............you can't make a blanket from 2800rpm onwards claim.
By the same token you can not make a broad statement about a L67 being highly expensive to modify, it comes down to how fast you want to go, the faster you want to go the more $$$ it will cost you.
There are more and more L67's in the 12 second bracket these days just running bolt ons.


As for spooling a turbo, again it comes back to set up, turbo size, cam type, fuel type and tune. Some come on a bit quicker some a lot later, i used 2800 as a bit of an average, hence the use of "about".
 

Husky

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By the same token if you want something to make power without having to sell your first born and left nut don't go a L67.
As for the power delivery, depends on turbo selection as to when it makes power..............you can't make a blanket from 2800rpm onwards claim.
I can have an L67 fitted for under 4 grand, a raptor is 5 grand just for part.
 

drippy

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I have just finished my conversion to a l67 in my vy, I did it for $1000 bucks give or take a few dollars, I used my existing wiring and extended about 10 wires,

Not that hard to do if your handy with tools, old engine out new one in took one Saturday then the Sunday I fiddled with wiring,

I went from a raptor charged setup to the l67, not as much top end power but I'm looking at bolting the raptor on as well.. :driving:

Just keep an eye out for a cheap setup or whole car so you have all the bits you would need
 

Pollushon

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There are more and more L67's in the 12 second bracket these days just running bolt ons.
Care to show us some? That's a misleading statement. There are L67's here with 10psi upgrades, CAI, extractors/exhaust and 1.91 rockers still making less than 200rwkw and running low 14's.

I can have an L67 fitted for under 4 grand, a raptor is 5 grand just for part.
The Raptor will put out up to 50 more rwkw than a stock L67. It can be fitted by a blindfolded monkey too :)
 
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