Hey Per, just saw your last two updates. Regarding the meet that you went to, did you guys get to drive the 142? How is the new suspension??? How's the new sound deadening? That looks like something that i'll need to look into... Also, about the dyno: Personally i think those wheels are extremely ugly, no offense, and they look very heavy. Although being steel, the stock rims were skinny, these wheels are not as skinny, (15x6 right?), and don't really have a light "spoke" pattern(not really spokes...). Also, the added width of the tires will also add weight. So what i'm thinking, but this doesn't necessarily make sense, is that the extra weight of the wheels accounts for your drop in power. But i don't see how that makes sense when you're doing faster runs to 60 mph. Maybe on the dyno the car goes through the rev range faster and this increases the effect of increases wheel/tire weight. Just an idea... Keep up the great work! Let us know how it is working out! Peace,
Kyle

http://www.classicmotorsports.net/142page2.html

Those wheels are 17 lbs...which is about the same as the more common Turbo wheel.

Per

Weight of wheels only affects the power output under hard acceleration.
(because you have to accelerate the weight of the wheel also and that takes
power. It doesn't take added power to keep it rotating once you spin it up.)
At constant speed weight of wheels or flyweel has no effect on measured
power. So for a normal dynamometer run, rotating weight is of no consequence.
--
George Downs, Bartlesville, Oklahoma, Central US

But on a Dynomometer you are accelerating as hard as you possibly can in fourth gear usually. Depending on how quickly the engine revs up in a dyno "pull", the quicker the "spool up", the greater detraction the heavier wheels and tires will make.
Kyle

Sound deadening works well...lighter and much cheaper than dynamat. I'm also experimenting with www.koolmat.com over the transmission tunnel.

Suspension works well, but the Bilstein TC shocks aren't stout enough to handle the VPD springs, so I'm getting HD Bilsteins.

As for the dyno results...I'm not sure why the results were lower...the numbers were significant (8-10hp, same for torque) Which is way more than I'd expect from a lightened flywheel for example. Found a similiar issue with our 122 project...dyno numbers much lower after a OD install. I wonder if its the oil pump that builds pressure? Car is running well otherwise...just "pokey" after installing the M41.


Oh, and I've located a set of Panasports...so the "ugly" wheels are for sale with new tires

Per
grmper@aol.com

I presume the Panasports are 14" rims ... otherwise, you'd just swap the tires over, right?

Alas, handling will suffer with a taller sidewall, so there's a tradeoff.



-- Kane ... 195/70/14's on mine's ... and they sure are squirmy!
--
Blossom II - '91 745Ti/M46 ... Bubbles - '74 144GL/BW35 ... Buttercup - '86 245GL/AW70 ... The Wayback Machine - '64 P220/M40

Makes sense that even a disengaged OD would offer some parasitic drag, although I've never seen it quantified before.

You're just gonna have to build 8-10 more HP into the motor then, right?

8^)