RALLIART UNDERDRIVE PULLEY INFOR PAGE
PERFORMANCE improvement of around 6-7whp and around 9ft/lbs of torque
FAQ Page
What is it?
A lightweight crank pulley that is under-driven to release more power in unsprung
weight from the engine. It results in an under-drive of around 25%, which
frees up power.
What does it fit?
It will fit 2004-2006 US Ralliarts with the 2.4 MIVEC engine. It will also
work on 2006 Eclipse GS models and the 2004+ Outlander with the 2.4 MIVEC
engine. It will work on auto or manual transmission vehicles. Other applications
are unknown although if you find that it works on something else then please
let me know!
What are they made from?
The pullies are produced from high quaility T6061 spun aluminium. It has a
very good tensile stength, will not rust, warp, and will always look great.
What is the weight differences?
The underdriven/lighter pulley is .58lbs and the stock unit is 3.911lbs. This
is nearly 85% lighter. This weight was done on a calibrated grams scale used
at the Backwoods Racing engine shop.
Is it safe?
Yes, the RA has a stock harmonic pulley, which acts as a dampener against
vibration on the crank. The stock crank is semi balanced although the balance
shafts in the RA engine do the primary job of dampening true vibration amd
balance of the whole engine. The stock pulley is meant to smooth idle out
and keep vibrations inside the cab happy. On a stock car or after a few thousand
miles your RA develops worse vibrations/rattles then you would ever be able
to feel with this pulley.
What are the long-term effects?
There are several cars of various different makes that have run lighter/under-driven
pulleys for years without any problems with the engine, transmission, etc.
In my short term testing on the RA I have seen no adverse effects, no check
engine lights and I have more than made sure I was hard on the car to bring
out any effects there could be. I feel 100% safe selling this pulley to any
RA owner.
Where will I feel power?
On a stock car or modified RA you will feel gains. This pulley improves low-end
torque and also makes the accelerator pedal easier to apply it makes the engine
rev quicker to redline.
How will such a pulley affect my awesome sound system?
I had AutoZone hook-up a charging system tester and it showed readings the
same as stock. There was no loss in AMPS /VOLTS. This car has the stock battery
and no other power related modifications. You can keep banging and rolling
with this pulley!
Will this affect your warranty?
As with any modification there is always a possibility that there could be
unseen effects where problems could be caused. It is up to you to do the bait
and switch method when going in for service although I doubt this would really
matter. These pulleys are balanced and should cause no engine damage or warranty
concerns when at service. As always any damages resulting from modifications
are the responsibility of the owner of the car and I will reserve no rights
to any liability from damage this pulley could cause on your vehicle.
How long does it take to install?
If you do this yourself you will want to set aside around one hour of time.
At a shop this should take about an hour of time for them to do. Do not let
them over charge you. It does not require any special or complicated tools.
Do I need a harmonic dampener?
The main purpose of a harmonic dampener is to reduce vibration inside the
cab and to make the engine run smoother. I felt no difference in this with
the better pulley although it is a question that was asked so I wanted to
answer it.
What about this pulley and the SC Kit?
A supercharger is belt driven. Changing the stock pulley to a lighter/under-driven
pulley will directly affect the rotation of the belt and will require a different
calibration of the pulley used in the SC system. The two parts can work together
although you will need probably a smaller pulley on the SC to produce more
boost as now with the under-driven pulley now turns everything less. IT WORKS
GREAT ON TURBOCHARGED RALLIART!
Will this affect timing?
Timing is calculated from many different factors of engine RPM and multiple
sensors. This is a mechanical belt driven pulley, which does not require changing
timing and will not affect your timing in any way. Your timing belt and your
serpentine belt are two different belts.
Install Instructions:
Tools Needed:
* 1ž2” Drive Ratchet wrench with 3” extension
* 3/8” Drive Ratchet wrench
* 3/8” Drive 12mm long extension
* 3/8” Drive 10mm long extension needed to remove splashguards
* Allen wrench of medium size to hold pensioner
* Jack and Jack stand to hold up car
* 4 way to remove lug nuts
* Various screw drivers Phillips & straight to remove plastic splashguards
* Your new Pulley
* Your new Belt
* About One Hour of TimeDirections:
1. Park your car in a level safe work area, let your car cool for a little
while if needed.
2. Loosen the lug nuts a few turns on your passenger right front wheel
3. Jack the car up and support it securely on a jack stand
4. Remove the wheel/lugnuts from the car
5. Remove the splash guards behind the strut and under the oil filter area.
This step is difficult, not technically although will take some patience.
6. At this point you will pop the hood if you have not done so already. You
will now want to observe the belt routing. Take notes if you need to.
7. Next step is too loosen although do not remove the 4 bolts on the stock
pulley
8. You will now want to observe the tensioner. You will see the part on the
tensioner where the 1/2" drive rachet goes. At the bottom left corner
of the tensioner you will see a small round hole where the Allen wrench goes
into. You do not want the allen wrench any farther than 1/2" into this
hole.
9. Next you want to take the 1/2" drive and pull it towards the front
of the car which will take the tensioner towards the rear of the car. This
will begin to remove tension from the belt.
10. At the point which you cannot pull the tensioner any more you will now
see that your Allen wrench can be pushed through to hold the tensioner back.
This step can be done with one person although it is difficult to hold the
tensioner back and then push the Allen wrench through.
11. You can now let go of the wrench and the belt tension should be free and
the tensioner should be held in place.
12. You will now remove the belt from the car taking careful note of how it
is routed.
13. Next you will remove the 4 bolts from the stock pulley and remove the
pulley from the car.
14. Next you will put the better pulley on making sure to line of the notch
on the crank to the proper hole on the pulley. This is easy to do and there
is only one way to go
15. Next you will put the 4 bolts on and tighten them down so the pulley is
no longer loose.
16. Now you will prepare your belt by removing the folds and trying to straighten
it out like the old belt
17. You will now put the belt on the car, make sure it is set in all the pullies
correctly
18. You will now remove the Allen wrench on the tensioner by turning the tensioner
towards the rear of the car by using the 1/2" ratchet.
19. Now that you have belt tension tighten the 4 crank bolts down as hard
as you can. I do not have torque specs for these.
20. After this do a final check of the belt and the pulley to make sure everything
is tight and the area is free of tools and anything that would hurt a test
start.
21. Test it by starting the car and observe the belt and pulley to make sure
everything is tight and spinning correctly. Make sure the belt is on all the
pullies and hasn't moved over.
22. After testing you will now be ok to put the splash shields back on, put
the wheel back on, hand tighten the lug nuts, raise the jack, remove the jack
stand, lower the jack, then double check the lug nuts to make sure they are
tight.
23. Go drive your car, be impressed with the results and tell your Ralliart
friends to buy one.
Click on pictures for larger ones, then click back to return to this page!
Testing & ResultsTesting:
Before actual development of the pulley I was using an EVO pulley in place
to test underdrive and driveability characteristics. After shredding a belt
I noted some revisions has to be made and I sent away the stock Ralliart pulley
to be CAD designed for the CNC process. The pulley I am selling is custom
made for the Ralliart. The EVO pulley will not work on the Ralliart! I have
repeated testing with the custom made Ralliart Pulley and have seen no negative
effects.
During testing I made sure everything was ok. I tested the charging system
at Autozone and it read normal. The AC blew just as cold and there was no
change in power steering effort or effect. The car is so much more fun to
drive. There is added torque down low and then a happier revving engine up
top. I did my best to test cold start, driveability, and hard stops to look
for issues and returned with none. I was not easy on the car during testing
and I had no problems. This is a bolt and play part.Results:
I first want to thank everyone for the wait involved in this process. I will
assure you it was worth the trouble. The test was done at Backwoods Racing
in Midland, MI. They feature a Mustang Dynamometer with inertia rollers. Their
Dyno is 2 months old and the customer service was excellent although the Dyno
as explained by the shop was not setup for a tuner car and their software
was more suited for AFR and certain speed tuning. I had a total of 12 runs
in, 8 were HP pulls and 4 were 1ž4 mile pulls. Their software has the luxury
of performing a 1ž4 mile on the dyno, which is very cool although I feel the
results are a bit high, although the difference shown below is what is important.
The Mustang Dyno showed very low HP for this car, which is unlike the Dynojet’s
that I have seen almost everyone else post. What is important though is the
differences between the stock and the under-driven/lightened pulley.
The test conditions here in Michigan were horrible to any real high HP pulls.
If none of you know how humid, and hot things are then take my word for it.
I am not using this as an excuse although if the conditions were better like
less humidity, higher barometric pressure and lower temperatures then results
would have been better. Furthermore the dyno had a fan that was very poor
and probably put out as much pressure as a standard box fan. Conditions were
as follows:Temperature: 90 F
Barometric Pressure: 29.05 milli-bar
Humidity: 85-90%
The HP (horsepower) pulls were started by shifting through the gears and getting
to 4th gear on the dyno and then going from 60mph to 95/100mph. So the charts
you will see only show from around 3500rpm to redline around 6500rpm in 4th
gear. Under the hood you could feel the intake piping and everything else
heat up quite a bit. A couple of runs I iced the intake and it made no real
difference. It was not until the last 4-5 runs that I am actually showing
the data on which you will see the differences. I first ran the stock pulley
and the power was similar between all runs with the stock pulley. After then
I got this bright idea to reset the ECU, put the better pulley on and then
try again. The ECU was unable to compensate the difference and then pulled
timing, which lost power. I could feel this happening on the dyno and knew
there was a problem. The shop recommended I try the stock pulley again and
at this point I was able to get the same results again as I got in the very
first test. At this point I pulled a quarter-mile run on the dyno for later
comparison. Then right on the dyno I switched back to the better pulley. On
first run you could tell the dyno was a bit quicker and with the lighter pulley
and improvements were made. The last runs showed improvement of around
6-7whp and around 9ft/lbs of torque . Sweet we have been waiting for this!
This is very, very good. On a Mustang Dyno that simulates real world horsepower
this shows very useable power. On any other dyno you should show gains somewhere
around 10whp. The quarter mile times also dropped too. With the stock pulley
I ran a 15.890. With the better pulley I ran a 15.730. These times as explained
earlier were on the dyno. What an interesting way to go 90mph standing still!
This is good for a tenth+ off the quarter. Very cool!
THANKS JOE!