Underdrive Pulleys

[The Unforgiven]

The manufacturers don't recommend them for the power levels most modded T's are making. There isnt really much point chasing 10 to 15 rwkw for a car that's so easy to get big hp out of...

←

Why don't they recommend them? Do they think the oil pump gear are suspect at higer power levels? Or do they think it will affect the internal engine balance? I would have thought that the latter would have been detrimental to all engines.

[falconutebeast]

Hey NOSXR, im having trouble finding a autoshop that stocks the new belt.

I've rung up autobahn and repco and they done have it on their system, then I tried peterwarren and they dont have it either.

where did you get yours from?

[Guest]

I got my belt from,

A1 Autos

24 Carter Rd

Brookvale NSW 2100

Call them on (02) 99072980

These guys got me the belt I needed at 2/3's of Fords price and got it for me with in hours of me ordering it.

Nice guys tell them I gave you their details.

[falconutebeast]

Thanks mate, ill give them a ring tomo morning

[falconutebeast]

alrighty, I called up some other shops that were local to where I live and same deal, "no we done have it or stock it, not on our system"

so I gave the number you gave me, which was a mechanic?:o , but he gave me the shop's phone number I was after.

Phone again, and this time it was the right place.He could get it all in by monday, I then asked if I could get it posted cos I live so far away freom the store( at least 1.5 hour drive each way), they dont post, but the storeman was nice enough to tell me that there is a granville store.

So I gave the granville store a call, was able to order in the belt and have a timing case seal ready for me to pick it up on monday afternoon.

[Guest]

Very good to hear mate.

Do post us the detail of the grandville store, how much did they charge for the belt?

Happy our happy and do post up all your results.

[falconutebeast]

Graville store

Address: Cnr Bold & Cowper Streets, Granville, NSW 2142

Phone: 02 9682 7900

Fax: 02 9682 7944

I don't know how much its going to cost me, ill find out on monday afternoon. I did order the 6PK2180 belt (cheaper one).

[MoreHPformyXR6]

Hi there

Just popped on to say thanks the Greg aka NOSXR as ive just purchased the 20% under drives through him as part of a group buy on AFF atm. Thanks again. Well I better hope back to AFF otherwise they will wonder where ive been.

[falconutebeast]

I got my underdrive Pulley installed yesterday at AutoTech.

Here is my dyno read out when I had my last tune.

You can see the power climbs then flat lines the climbs again, while the torque curve drops off dramitically mid way through.

Now here is the new print out, other mods I put on since last time are, I put in Jmm spark plugs in (autolite plugs) gaped them to 0.9mm. 3inch intake tube, BF XR8 headlight snorkle, I gutted all the fins out of the airbox, and a 160F thermo stat.

The main upgrade was the underive pulley.

Here you can see my torque curve is way up and doesnt plummet as servely as before.

Also the power curve is smooth all the way through, no flat lines.

And now it makes more and longer at the end of the rpm.

I'm very happy with the results, and I can feel the difference it drives now, very bloody toruqey now. And it pulls very hard now to 6k rpm

I Would highly reconmend this mod to anyone out there Team N/A or Team T

Thank you to the Autotech crew for doing your craftman ship work on my ute.

And a thankyou to Spiro for working his magic on the dyno.

And last thanks goes out the Greg (NOSXR), this mod has been an awesome buy, thankyou for organising it and your dedication to Team N/A

[Lawsy]

Turning an alternator under load at 1rpm is hardwork... The load has an electromagnetic and mechanical advantage on you.

If you want to make the same power using as little torque as possible, all frictional and heat losses aside, you would want to turn the thing at at a much larger speed, since torque required will be reduced... This is similar with all accessory functions. They require a certain power to opperate, not a certain torque. If you balance the equation, it simply means that for the same power, as RPM increases torque decreases.

In practical terms, it requires more torque to turn the alternator at idle (probably 25Nm's or so) than at 6000rpm (probably like 10Nm's. It would be less if the ignition (spark) load wasn't greater at higher RPM).

This is why there is a much greater increase in torque at lower RPMs.

Its good stuff, I love these sort of simple, practical and just so usefull modifications... The physics is nice and simple, the gains are real and do not require 6000 rpm to be felt. Infact, the largest gain is at the lowest possible load point, tappering off as RPM rises. Most usefull increase you can get!

Awesome stuff :D

Edited 07/03/07 03:14 AM by Lawsy