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Topic: Underdrive Pullies (Read 2611 times) previous topic - next topic

Underdrive Pullies

Reply #15 –
Quote from: danzajax;218236
The spare engine I have has just the crank UD on it.

The Crank pulley is probably 80% of the benefit... In fact my set came with a same size diameter water pump pulley and a slightly larger alt pulley, which I never used... Seen some alts with a factory pulley same as was included with mine... No I don't remember what brand my set is, bought 'em back in '94 for a 5.0 Stang...

Underdrive Pullies

Reply #16 –
Thats what I wanted to hear!! I got a killer deal from a local member on the pulley, and I only got it cause I used logic, and figured that would be the biggest part of it.
RIP 1988 and 1990 Lincoln Mark VII LSC
I welcomed the dark side and currently am driving a 2000 Dodge Durango SLT plus, with a 5.9, Code named project "Night Runner"
Shes black on black, fully loaded, with headers, 180 tstat, e fan, straight exhaust into a cherry bomb vortex ler, full tune up, ported intake and T/B, MSD coil, and round aircleaner.
Mods to come: Fully rebuilt and heavily modded 46RE, and a richmond rachet locker.
my $300 beater ;)
R.I.P Kayleigh Raposa 12/18/90 - 2/24/07

Underdrive Pullies

Reply #17 –
so what brand is everybody getting? march? aluminum or
steel? had a set on my gt mustang and 93 f150 years
ago. both were march.--irv

Underdrive Pullies

Reply #18 –
Dogcharmer, I believe your problem is your stereo not your pulleys.
Someone back me up here but didn’t the 93 cobras come stock w/the U/D crank pulley but not the alt or the waterpump.

Underdrive Pullies

Reply #19 –
mines aluminum no idea the brand, bought it used
RIP 1988 and 1990 Lincoln Mark VII LSC
I welcomed the dark side and currently am driving a 2000 Dodge Durango SLT plus, with a 5.9, Code named project "Night Runner"
Shes black on black, fully loaded, with headers, 180 tstat, e fan, straight exhaust into a cherry bomb vortex ler, full tune up, ported intake and T/B, MSD coil, and round aircleaner.
Mods to come: Fully rebuilt and heavily modded 46RE, and a richmond rachet locker.
my $300 beater ;)
R.I.P Kayleigh Raposa 12/18/90 - 2/24/07

Underdrive Pullies

Reply #20 –
Ive been selling underdrive pullies for 85 and up 5.0
Mustangs since well they first came out in the mid 80s.
Kaufman Products made the original design back then.
We put them on a boatload of Stangs back then...
But most people just ran the Crank and Waterpump pullies
and tossed the alternator pulley in the trash.
The smaller crank pulley would enable the crank to spin
faster, while the larger water pump (and alternator if you
chose to install it) would slow down the accessories a bit.
This would release whats known as Parastatic Energy.
Either way, its a good idea to a point, but if you slow the
accessories too much, you can run into a cooling probelm or
a charging problem from your alternator/battery.
The overall gain was maybe 3-5 hp on a good day, but they
seemed to help and in theory they do work.
Move on to the late 80s..we had a customer come in with an 87
5.0 Cougar who wanted more hp. We installed the 2 pcs only
pulley kit (crank and w/p pulley only) didnt want any charging
problems, on the guys Cougar.
He came back a few weeks later and it was weird, he came back to our
shop and demanded to know what all we did to his car. At first I
thought he was mad, but once I convinced him all we did where the
pullies, he proceeded to tell me his gas mileage went up 5-7 mpg
in town !! The Hp gain was fair, but couldnt get over how much his
gas mileage went up.
And since then every Bird or Cougar and Lincoln we put the 2 pcs pulleys on, always had the same or very similar results.
Funny thing is, the results where never the same on the Mustangs.

Underdrive Pullies

Reply #21 –
The only difference I can think of is that the Mustang has an 9 blade fan and our cars have 7 :confused:
Fox-less at the moment
 

Underdrive Pullies

Reply #22 –
visually that may be the only diff
could have to do with gearing, weight,
ecu maps that have to do with timing curves,
hard to say ..
the end results where always the same

Underdrive Pullies

Reply #23 –
Quote from: motorsport007;334367
visually that may be the only diff
could have to do with gearing, weight,
ecu maps that have to do with timing curves,
hard to say ..
the end results where always the same


Very interesting .
Fox-less at the moment

Underdrive Pullies

Reply #24 –
Quote from: hypostang;334331
The only difference I can think of is that the Mustang has an 9 blade fan and our cars have 7 :confused:


Mine now has a 9 blade with no difference in fuel economy.
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

Underdrive Pullies

Reply #25 –
Quote from: thunderjet302;334451
Mine now has a 9 blade with no difference in fuel economy.


Only driving 400 miles a year  how can ya tell? :rollin:
Fox-less at the moment

Underdrive Pullies

Reply #26 –
I haven't had to fill it up more than last year;)
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.