TheSamba.com :: View topic - power pulley to use one or not to use one

Sat Apr 25, 2020 6:22 am

back in the 1970s I used a power pulley on all my vw motors but we had good gas back then high test was about 105 oct. what do you think good or bad to use a power pulley spencerfvee

Sat Apr 25, 2020 6:23 am

Not good if you go on long highway trips.

it turns the fan slower.

Sat Apr 25, 2020 7:13 am

They work great with e85.

Sun Apr 26, 2020 10:56 am

I am trying to go the other way and run a 36hp pulley that is about 3/8" bigger, I live in the desert and want better cooling.

eQ

Sun Apr 26, 2020 12:18 pm

earthquake wrote: I am trying to go the other way and run a 36hp pulley that is about 3/8" bigger, I live in the desert and want better cooling.

eQ
Here you go
http://vwparts.aircooled.net/Super-Cool-Pulley-and-Belt-Degreed-p/super-cool-pulley.htm

Sun Apr 26, 2020 12:52 pm

You could use a power pulley and Porsche generator pulley...a little less speed than stock, but more than just the power pulley

Sun Apr 26, 2020 7:46 pm

Saco makes a bigger top pulley. Can change it out if runs too hot. Also if you already had parts balanced.

Mon Apr 27, 2020 7:34 am

I think the power pulley is best suited to use in a combination street/strip car if you don’t want to remove the belt before every pass. It would also be suitable for a light weight rail buggy. I agree with the others on it not being well suited for highway driving. Ambient temperatures will play a role as well.

Mon Apr 27, 2020 8:14 am

earthquake wrote: I am trying to go the other way and run a 36hp pulley that is about 3/8" bigger, I live in the desert and want better cooling.

eQ

I wanted to run a 36hp pulley too so i could easily mount a small trigger wheel until i read that they will sit too far back and wont line up with the gen/alt pulley. :(

Maybe, just maybe... someone makes a shim?

Aircooled.net says, “ Pulley INCLUDES the belt! Pulley can NOT be used on full flow engines (the pulley hits the return fitting) or engines with filter-pumps.” This may be something to think about when running larger than stock pulleys. So, does someone who doesn’t want to spend big bucks for a 356 gen pulley have the option of buying a smaller aftermarket alternator pulley?

Mon Apr 27, 2020 8:00 pm

I am running a power pully on my 1776 street rod bug, 11-1 comp with E-85.
has 36 hp doghouse shroud, been thinking about changing out
the fan for 36 hp fan, less blades so will run a little hotter.

I also have a 356 upper pulley on my VW Thing, that I installed last
fall, scary fan noise, really winds up the fan …. I have not driven,
thinking about going back with the stock pully …. I really do not
like the fan noise sound :(

Tue Apr 28, 2020 6:00 am

txoval wrote: You could use a power pulley and Porsche generator pulley...a little less speed than stock, but more than just the power pulley

anyone knows whats the diameter of the Porsche generator pulley and stock VW pulley?

Tue Apr 28, 2020 7:04 am

I don’t have the exact measurements but it’s about 3/8” smaller in diameter, close to 10%

There are plenty of samba threads on this in the vintage speed and bus forums

Tue Apr 28, 2020 7:48 am

I always turned the crank pulley one full revolution and counted the amount of turns that the upper pulley would make.

Of course this does not account for slipping belts, but there are many different sizes of pulleys and belt sizes (riding higher or lower in a pulley will turn slower or faster) to get what you want.

Tue Apr 28, 2020 7:59 am

spencerfvee wrote: back in the 1970s I used a power pulley on all my vw motors but we had good gas back then high test was about 105 oct. what do you think good or bad to use a power pulley spencerfvee

For street driving, I offer no warranty to any customer that installs a power pulley on an engine I build.

Wed Apr 29, 2020 2:49 am

pupjoint wrote: txoval wrote: You could use a power pulley and Porsche generator pulley...a little less speed than stock, but more than just the power pulley

anyone knows whats the diameter of the Porsche generator pulley and stock VW pulley?

Keep in mind The 36hp generator pulley is the same size as the porsche 356 generator pulley ...you can buy them new for around 29bucks from Wolfsburg west. Or buy one in the classified adds here on the samba .shoot a 356 generator pulley you will pay much more just because it's for porsche ...but hey if you guys like to give your money away or brag that you have a porsche 356 generator pulley go on a head to all reach it's own ...

Wed Apr 29, 2020 12:23 pm

The equalizer crank pulley from CB is a nice compromise between a stock diameter pulley and a power pulley. I don't remember how much smaller it is than stock, but it's small enough that I have to use a smaller (and thicker) 10x900 fan belt (the stock belt is what, 9x905?), and it still rides high on the alternator pulley, which slows the fan down even more.

I don't notice any detrimental effects to cooling with this setup, but I also have a venturi ring in the shroud, and the engine is a bit more efficient than stock, so it generates less heat to begin with.

Just thought I'd throw that out there.