RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   3rd Generation Specific (1993-2002) (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/)
-   -   aluminum underdrive pulleys are a MAINTAINENCE item (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/aluminum-underdrive-pulleys-maintainence-item-781445/)

FDSeoul 08-27-08 02:27 PM

Chadwick-Dan----- please keep us informed on the production and availability as soon as possible. if knowledge was a given on this issue with the slippage these should sell like hot cakes. what manufacture are you using for the bearing???

G's 3rd Gen 08-27-08 03:07 PM

subscribed..

FearNoPiston 08-27-08 03:30 PM


Originally Posted by Chadwick (Post 8499670)
I will be running a group buy through the forums right after Nationals which is mid Sept. Don't recall the bearing manufacturer off the top of my head, they were specked by a mechanical engineer friend for their dynamic radial and angular load and RPM rating.

Is there any chance that you will be offerering different colors? for example I have the greddy kit and it would be nice if that pulley was blue as well.

I will have to keep my eye open for these to come into group buy :)

-Chance

Dudemaaanownsanrx7 08-27-08 07:09 PM

sure enough mine slips too. howard have you tried the modified pully with the H's etched into it? did it improve the grip?

Dudemaaanownsanrx7 08-27-08 07:12 PM

too bad there isnt a belt replacement that has some kind of ribs on the outside, course that might eat through the aluminum even quicker. I like how much simpler the engine bay is without the extra belt routing, there must be a good solution besides adding more or new parts.

cozmo kraemer 08-27-08 07:14 PM


Originally Posted by FDSeoul (Post 8499413)
pineapple used to make one as stated above. perfect even for guys running large single, It is the size of a half dollar in diameter. They really need to make them again.

This is exactly the reason why the pulley they were selling cost so much. If you use a larger pulley it hurts turbo clearence but also puts much less strain in the bearing inside the pulley. They were able to go so small on their pulley because they were using a bearing that was good to an extreme RPM. This greatly increased their cost. The original price was close to $300 I think and I heard they still lost money on the deal. The little CNC bracket and bolt cost was trivial in comparison.

Personally I didn't need the huge clearence, so this pulley by Chadwick would have most likely worked for me.

cozmo kraemer 08-27-08 07:32 PM


Originally Posted by Dudemaaanownsanrx7 (Post 8500668)
I like how much simpler the engine bay is without the extra belt routing, there must be a good solution besides adding more or new parts.


The solution you are looking for is an electric water pump.

Maintaining the OE water pump requires you to use at least close to the stock amount of belt wrap. The only way to do this properly with the air pump gone is to install an idler pulley. There is no other way. You might be able to make some more elegant belt routing with a different pulley location (like the hot rodders do) but you have to have the wrap with the OE water pump, and this is the best way to get it. The idler pulley is in my opinion a very elegant and slick solution. Much better than the Greddy pulley kit which is just a very poor solution to the problem...again IMO. But then again, they got me to buy their kit before I realized that I needed the Pineapple Pulley to really be safe and eliminate belt slip.

FWIW. I posted my Pineapple idler pulley for sale and sold it in less than 15 minutes for, I think, $165 shipped. I got PMs more than 3 months latter from people wanting to buy it from me. I think there is a market there if someone can produce a good solution.

DCrosby 08-27-08 08:06 PM

What about an electric water pump ?

RotaryBuddha 08-27-08 08:39 PM

Another option instead of the standard aluminum underdrive pulleys are glimers. I know they make gilmer pulleys for 1st gens and 2nd gens, but never seen one for the 3rd gen.

http://www.tweakit.net/shop/product_...roducts_id=102

I know this could be accomplished by using the front housing/water pump from a second gen.

jaggermouth 08-28-08 02:56 AM


Originally Posted by RotaryBuddha (Post 8500931)
Another option instead of the standard aluminum underdrive pulleys are glimers. I know they make gilmer pulleys for 1st gens and 2nd gens, but never seen one for the 3rd gen.

http://www.tweakit.net/shop/product_...roducts_id=102

I know this could be accomplished by using the front housing/water pump from a second gen.

Yeah I really want a set like that.
But if you use the front case off a 2nd gen, then wont you need a custom oil pan?

Azcamel 08-28-08 06:51 AM

i just tried mine and sure enough it spins with little effort, great design Greddy!

ArmenMAxx 08-28-08 12:11 PM

If the grip on the w/p pulley was rubber I dont think we would have this problem

FearNoPiston 08-28-08 12:20 PM

so my noob question of the month:

Can I just turn the belt inside out? So the ribbed side hits the waterpump and since the alt and crank pulley have more surface grip will be ok???

FDSeoul 08-28-08 12:51 PM

^^^NO the 5-v-bans are there for a reason. the only current solution with out highly modifying would be retain your air pump or the pulley.

FearNoPiston 08-28-08 01:24 PM

:wallbash: :wallbash: :wallbash: :wallbash: :wallbash: :wallbash: :wallbash: :wallbash: :wallbash: :dammit:

seven samurai 08-28-08 02:04 PM

Wow, for once I can say I'm glad I still have my air pump connected?
I was thinking about removing it too but with California smog Laws and My laziness, I have left it on.

FDSeoul 08-28-08 05:08 PM

^^^^ same here lol

DaveW 08-28-08 07:08 PM


Originally Posted by Samuel L Jackson (Post 8499262)
Someone needs to come up with a standard rotation water pump that is also an upgrade. Then you could use a standard serp belt and rx-8 pulley. They do not suffer any slippage even at 9000rpm, because the ribbed side of the belt is making contact on the pulley, this is the side with the softer rubber that provides better grip. The topside of a serpentine belt is slick and not really meant to provide any grip, and that is part of the problem we face.

The other thing about the multi-groove belt is that, like a standard V-belt, the "V's" wedge themselves into the pulley grooves, providing more surface-contact force and area and result in more torque capability. A flat belt (or a V-belt running on a flat surface) does not have that advantage.

Dave

PandazRx-7 08-29-08 12:38 AM

Another idea that came to mind would be to fab an alternator adjustment bracket that allows it to be pulled higher, allowing the belt to hug the waterpump pulley some more.

I guess the belt contact wouldn't be a much as we would like, but it can be just enough with the larger diameter aftermarket waterpump pulley.

Any thoughts?

silentblu 08-29-08 02:23 AM

anyone think of adding a grooved pulley to the water pump, and using two belts? one going around the alternator and main pulley, and the other one flipped inside out to hug the water pump one?? if that makes sense

just a thought

Dudemaaanownsanrx7 08-29-08 07:25 AM

Yeah that makes sense. I thought of that too. I don't know if the two belts would ride on eachother correctly. Maybe if the other pulleys were deeper or the belts were glued together. Then there is still the issue of contact area. Although with two belts it would put more pressure on the pulley even if it wasn't a grooved pulley it might work better. I thought of using some kind of rubber stuff on the outside of the belt to make it stickier but that would prob wear off in short time

FDSeoul 08-29-08 01:16 PM

keep in mind that the slippage occurs at the higher RPM range and once the heat come in to factor the only real solution to insure the proper water pump rotation is maintain your stock air pump or install a idle pulley. :( just wait for the group buy or start calling paineapple racing and put pressure on them for a re-run

ArmenMAxx 08-29-08 04:08 PM

The pinapple idler kit will need the stock alt and water pump pulleys correct?
Does anyone know if it will also use the stock belt size also?

FDSeoul 08-29-08 05:17 PM

^^^does not!!!! you can us any aftermarket pulley it is designed to maintain the original belt travel path. and the size of the belt needs to be smaller after installing the kit. same OEM path but shorter. the original pineaplle pulley is the size of a U.S. half dollar.:)

silentblu 08-29-08 08:06 PM


Originally Posted by Dudemaaanownsanrx7 (Post 8505495)
Yeah that makes sense. I thought of that too. I don't know if the two belts would ride on eachother correctly. Maybe if the other pulleys were deeper or the belts were glued together. Then there is still the issue of contact area. Although with two belts it would put more pressure on the pulley even if it wasn't a grooved pulley it might work better. I thought of using some kind of rubber stuff on the outside of the belt to make it stickier but that would prob wear off in short time

Well i had a problem sizing belts, so i ended up with a bunch, pretty much you can find them in 28.5inch, 29inch, 29.5inch, and 30inch. They fit into each other quite nicely, so i don't see there being a problem of contact.

would changing the rotation of the water pump work? My friend put the belt on the wrong side of the pulley one time, and ran it for maybe a week until i told him it was backwards.


All times are GMT -5. The time now is 01:20 PM.


© 2024 MH Sub I, LLC dba Internet Brands