2.5 Vs 2.8 Stock for stock...

[BobRocket]

I hope there is no limit to dumb questions, because I'm sure I'll ask quite a few!!!

Please do not think that I have not done my research on the subject. I know the 2.8 was only rated 1 HP more but also 20+FT LBS Torque higher... I did get to test drive a 2.8 but have not driven the 2.5. The 2.8 Was pretty impressive for such a low HP rating. I am used to american V8's and turbo V6's (Buick GN, Turbo TA's) and still found the 2.8 to be quick. Probably a 14 second car....

How big of a difference do you all see in the two engines, from having driven both? Is it really that signifigant?? Would you avoid the 2.5L ? (1994 model year I am looking at)

Thanks!


Bob

 

[frolf]

they are both incredibly strong engines. I have never driven a 325, but one thing to note is that when they bumped it up to 2.8 they managed to square out the engine. 84mm bore x 84mm stroke (perfectly square). This makes for more even power curve (large bore promotes high rev power, long stroke promotes bottom end). Another thing to note is that in 1996 when they went to the 2.8l, they introduced VANOS.

another thing: i'm not sure if they had this on the 325's or not, but on my 328iS my exhaust system has a backpressure valve. When the engine is at low RPM's the valve stays closed providing additional backpressure which means additional low-end torque, as the RPMs increase the valve opens up which gives you that high flow you need for high rev horsepower.

 

[jcblaschke]

I have a 93' 325is, which has VANOS, and for me it's enough power, throughout the band. If you're power hungry then i would go for the 328, both are good engines, and if you take care of them they will last a lifetime.

 

[ra328i]

it's pretty simple really. here ya go.
http://www.internetautoguide.com/reviews/1996/1996_BMW_328i.html

in this review they speak of the differences in power. hp isn't that impressive at all, but the torque difference is huge!!! do some thinking..

 

[frolf]

haha, stupid me. i was thinking about the climate control (don't ask me why) that got changed in 96. you are correct, single vanos is there.