I need to know some info on under drive pulleys (correct info) I hear its not worth the risk because it messes with the engine harmonics, I also hear that when you do this upgrade it releases a lil more HP! Whats the deal about these underdrive pulleys (the pros and cons)?

 

Your engine will be fine.. I have 300k+ on this engine with one. We don't have harmonic balancers.

 

I would go with a lightweight stock sized pulley. An underdrive will give you 1 or 2 HP over a stock sized lightweight pulley, but at the cost of reduced A/C performance.

 

Underprivileged pullies are all good but it kills the output of ur alternator at idle once it heats up. I have a volt meter gauge and it clearly gets sucked down when at alight with lights and AC on. This won't be apparent if you just added it on cause it takes a few weeks for the battery to start not being able to really hold a charge.

When I got my new battery ittookall of 2 weeks for it to not really hold a charge.


I still ain't taking off the pulley tho

 

Ive never had a problem in all the years and miles (about 300k miles on this battery) ive had mine on

 

All you need is the crank pulley. It was the single biggest difference in RPM speed up on my car. The thing was SO quick to rev. Never had any issues. The option racing pulley was the one I had off ebay. Not sure if they still make one.
Hot humid south Florida....never had any AC issues. And it was on almost all year long.

 

Option racing is still around here is a link:

http://www.ebay.com/itm/98-02-HONDA-...234#vi-content

Thanks Fuzzy glad to hear that you have used this brand with no trouble, I get a little leery about some of the thing that you find on Ebay.

 

thanks for the link, i think i may make this purchase.

i was debating on purchasing the full pulley set from here;
http://www.2kracing.com/Product/56394.html

sounds like it may be best to replace only the crank pulley and not the p/s or alternator.

 

only $30 damn

 

50$ ebay UD pulley on for 3 years 100K with a 29$ homedepot lawn tractor battery of 290cca for is weight savings with zero issues and AC ran every day in florida

 

for those of you that have the option racing underdrive pulley, what belt would you need?

 

When I got the option ud pulley I made a thread here on azine if u dig around you'll find it for sure and it's got all the belt sizes.

I will say tho I have gone through 3 batteries in6 years and just had to buy an optima yellow top to cope with the constant charge and discharge.

The pulley is made well and is symmetrical but it is actually a fraction too small and because I have a volt gauge hooked up u can see at idle the volts just drop and drop. Most don't know this I'm guessing about the option pulley. If it is the same version I got then I'd reconsider just getting a different brand or get the lightweight stock sized one.

But if ur stubborn like I was, time will show you that I am likely right and am trying to help you in the long run.

Good luck

 

Is there a higher output alt available and if so do you think it would make a difference?
@dannysayaseng: I have the Gates belts that came with the UR pulley I bought from a member here but if we don't know the Options pulley is the same size that may not help.
I can measure the diameters of the pulley if you know the diameters of the Options pulley.

 

There is the odyssey alt but I doubt it puts out more at super low rpm. There is a threshold they need to operate at to make their baseline power.

The only thing you could do imho is find a smaller alternator pulley and that would increase the rotations. You only would need one 10% smaller I'd guess... But that would also chane the belt size slightly to a smaller one.

Personally I should do that. But I am so fet up with my car right now I cannot bare the thought of needed to do another thing to it. I'm already losing sleep over this things... Just don't end up like me... It's -15 here today when it pull my car into the garage today I will measure it for you bud

 

I have an actual volt gauge installed in my car at all times. I also have the option underdrive pulley and a 15 lb lightweight agm battery. My gauge reads a constant 14 volts even at idle. The only time the reading is low is when the battery is left off a trickle charger for awhile.

Still on my first braille 15 lb battery. Had it a few years now no issue.

 

my car reads 14.3 v on my glowshift voltgauge and i also have a trans temp gauge which is 100% identical reading to the actual cars internal atf temp reading. i hooked it up to a live scanner yesterday and did a bunch of check fro the trans flare i have.so i know the gauge is accurate cause it also is identical to the reading i get if i put a volt meter on the battery anyways...

so ur saying 14.0V...thats with all your accessories going at idle? seat warmers, rear defroster, blower motor on high, headlights, a/c??? wait 5 mins with everything running and if your still right then i presume they changed the design. i got mine about 5 years ago for 30$

the volts only drop if i have most of the accessories on.


it measures 5 3/4 inches on the outside diameter to within a 1/16 of an inch.

hopefully we can get to the bottom of this lol

 

I feel you on the fed up part but with me its this truck I bought to replace my old truck. I got it cheap so I'm still in the black but if I can't get it sorted out soon it I won't be. I need it for work.
I've never changed a pulley on an alt. Do they come off easy? I guess after you do that and find the right belt its good.
One more question. I know what its like to drive in traffic with a lightweight flywheel. This isn't going to be like that I hope. Sometimes rotational mass can be a good thing

 

No ... drivability was all plus plus I love it too much to remove it. Yet I am too annoyed to change the alt pulley. I'd imagine it's on there really well after 15 years and I don't feel like damaging the alt lol so I'm just dealing with it.

 

I don't have seat warmers. My car is gutted so less accessories. It stays at 14 volts with a/c on. I have no radio. I don't really ever use the rear defrost.

I can't really say for a car with all accessories, only my personal experience with my car.

 

I really find the rear defroster to be a big power draw, seat warmers I can't imagine being that much but who knows, my radio is alway pounding away.. Tho it is stock speakers I'm sure it draws a bit of juice and having the blower fan on high makes a big difference vs on low with the a/c on or off.

The big thing I noticed tho is when I bought a new battery it was much less obvious cause it could hold the charge. But when I had it in there for a month, the battery would not hold a charge worth a damn. Amazingly I never had starting issues, but if I left the car for 2 weeks and then went to start it it needed a boost. So it was definitley eating up my battery. And that's why I bought a yellow top optima cause I read it's good for discharging and recharging. I had to modify the battery tie downs by making them shorter and I removed the battery cover and the box it sat on. Personally tho it seems like the right choice... I think lol