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      08-28-2008, 12:36 PM   #64
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Drives: LPCs
Join Date: Dec 2006
Location: Tide Water Region

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1990 325i  [0.00]
I dont think the issue is that can it stand up to boost....I think the main issue is cracking the code on double vanos and second generation valvetronic. I believe the reason the offer the N52B30 based on the older block is because of dollars not boost.

Installing a cam is kind of silly as the car already has variable valve timing....lift and duration are both adjustable capable of infinite combinations.

This snippet from Road & Track best describes double vanos

Although with more elements, BMW's Valvetronic qualifies as state of the art in continuous cam-shifting. Teamed with cam-phasing of its VANOS (or, for both intake and exhaust valves, double-VANOS), the two systems offer continuously variable — and independently configured — timing and lift.

Valvetronic interposes a second intermediate rocker arm between each camshaft lobe and its intake valve. Lift is continuously variable by shifting the orientation of this intermediate element through its contact with an eccentric shaft.

In fact, so effective is this in defining the engine's breathing that BMW can dispense with the traditional butterfly throttle. This in turn offers the advantage of reduced pumping losses (those incurred on intake stroke with a closed butterfly). BMW says Valve-tronic is worth a 10-percent reduction in fuel consumption. Introduced on the 316ti 4-cylinder, the system is gradually finding its way into many of BMW's engines. (Even the new Mini has Valvetronic!)

Complication — its several rocking elements and necessarily strong springs — limits efficiency at high rpm. Valvetronic M isn't likely. But, at the moment, it's variable-valve timing's state of the art.

From a marketing perspective BMW is right on ....dont show your full hand early in the game....this creates a demand give consumers a taste of the balance & feel of the car...then relase the "good stuff"

...think how many people jumped from the 330i to the 335.

Last edited by smellthebeans; 09-21-2008 at 11:30 PM.