Underdrive pulleys [ merged 1/6/07]

[larryd]

Worth it or not? I'm thinking of going with the AEM tru-power pulley kit. Anyone used them?

 

[XMasta19]

...umm, good luck

 

[DBordersX]

, thanks, i know it's risky but I'm not too worried about this engine

I've been looking into it and i think I'm going to get the Howell 2.2 stroker. either the kit or the crate motor, either way, it won't be this engine, and when i do that I'll get the AF/X or unorthodox pulley for sure, this whole thing is just sorta temporary so i can get the car running and sell my other car (for mod money of course)

we'll see how this one goes though, i won't have the engine in the car for another week or so, it's slow going when you're a weekend warrior

 

[gsx951]

I think some of you guys failed metal shop.

Those pullies are made on a CNC lathe and are concentric. Balance is not an issue.

Undampened pullies FTL. There are plenty of threads to read regarding this.

 

[GsxProject]

I just installed a e-bay no namer onto my car and in my opinion I don't have a problem with it. The only problem with it is that it doesn't have the rubber in between it for the vibration dampening, but I also think that's something very hard to feel while driving. And so far so good, it's pretty cool looking, looks as if its not even spinning...!!!

 

[DBordersX]

i had to use the puller to pop the stock pulley off (that's all i tried, i read some stories about how hard it can be on here so i didn't even attempt it without the puller)

the opening for the crankshaft in the back of the pulley is ALMOST exactly the same size on the ebay pulley as the stock. i can put it on and take it off with my hands though, which i don't like .

so i'm a little worried about it slipping and not driving my accessories, but i don't think balance will be a problem

also, i think a little threadlock or something will make that fit a little better and prevent slipping, not to mention the crank bolt that's going back in there

 

[XMasta19]

umm...this thread is for a 420a underdrive pulley from ebay...we don't care what any of you bought or have heard about for any other car. Oh, and the pulley sliding on and off with ease by hand...

 

[gsx951]

umm...this thread is for a 420a underdrive pulley from ebay...we don't care what any of you bought or have heard about for any other car.

 

[DBordersX]

k guys, i was playing with my engine and i just couldn't bring myself to put that eBay UDP on

it was just too loose and I couldn't take it

sorry guys, i was hoping to be able to give some real info on this thing

i can for sure tell you it goes on and off WAY too easy for my comfort (i.e. with your hands and not a 10lb sledge/5 ton puller)

i guess i'll just get the AF/X one when i get my stroker motor

 

[bullettdsm]

k guys, i was playing with my engine and i just couldn't bring myself to put that eBay UDP on

it was just too loose and I couldn't take it

sorry guys, i was hoping to be able to give some real info on this thing

i can for sure tell you it goes on and off WAY too easy for my comfort (i.e. with your hands and not a 10lb sledge/5 ton puller)

i guess i'll just get the AF/X one when i get my stroker motor

MB

 

[DBordersX]

off topic but just an update

i got her running

new (to me) engine in and she started up the first time

life is good

 

[FasterImage]

I just ordered on last week, I race my eclipse every friday nite in a points class, so i never miss. When I get it on I will be sure to post the fitment, and any differences if at all, or any problems I have with it, as I thrash on my eclipse every weekend at the track. So I will find out how tough it is!

 

[GsxProject]

I put on a underdrive pulley on my car, but didn't think to see if it had a marking on it for the crank position. How would i go about finding out where to put a mark to do my timing and to set my crank position for tuning?

 

[EagleTalonTim]

You can put the original one against the new one and put some bolts or dowels through the bolt holes to line them up then etch a small visible groove in the new pulley.

 

[Boo5t_Addict]

Just so you know, the damper is built right into the stock pulley, so your underdrive doesn't have one. No offense but you'll most likely end up hurting your motor more than help it. Your bearings are going to see accelerated wear. I would personally advise against using an underdrive pulley, as it's just not worth the minimal decrease in parasitic horsepower loss.

 

[eclipsegst1990]

Just so you know, the damper is built right into the stock pulley, so your underdrive doesn't have one. No offense but you'll most likely end up hurting your motor more than help it. Your bearings are going to see accelerated wear. I would personally advise against using an underdrive pulley, as it's just not worth the minimal decrease in parasitic horsepower loss.

I 100% agree. I had this exact thing happen to my vehicle after a relatively new rebuild. didn't replace the damper "like an idiot" and it ended up failing on me making the bearings closest to the #1 cylinder to show wear. I started getting a spitting oil leak underneath the vehicle and it was pretty much 1qt/week. Please, get a GOOD damper and call it a day-billet if necessary. This simple part can save you hundreds of dollars and a series of migrains. The underdrive pully really doesn't free up much horsepower...just turn up the boost a little instead if safely necessary. Please accept my warning from personal experience and get a good damper.

 

[GsxProject]

Do they make after market dampener pulleys with the rubber still on it or is that to far fetched for a dsm guy to have?(light weight is what i mean)

 

[ndsti]

Look for a company called fluidampner, they make a very good underdrive pulleys!

 

[Sinner]

I have the chance to buy a used underdrive crank pulley, my question is do I need anything else like other pulley's or different belts or can I just bolt on this crank pulley in place of mine and be done.

 

[Locke]

You will need shorter belts. What brand UDP?

 

[Sinner]

I'm told it's an OBX pulley. Do you happen to know the part number for the belts that I would need.

 

[InfiniteGSX]

Are they worth it? I'm about to install my new head... and do the timing... But I have the problem of the stock beaten up pulley... It took alot of convincing to get it where its at, and I doubt it will go back on if I do get it off in one peice without some resurfacing around the crank where it mounts up... So while I have it off, should I just go ahead and spend 50 bucks on some belts and a underdrive pulley?

 

[speedy13]

no, but you can spend 140 bucks on a AFX one. I had that one on my 2gnt and loved it, At the time it came with the belts too. Give them a call and see if they'll send the belts. the best description I can think off as far as power goes, is it feels like you turned off the AC again. Car revs freer. after intake and exhaust, this would be my 3rd mod of choice for the 420a.

http://www.howellautomotive.com/index.asp?PageAction=VIEWPROD&ProdID=345

 

[syrushcw]

I have an unorthodox lightened pulley laying around. I'm debating not installing since it is not dampened it can cause damage to the engine. Especially since I don't have a balance shaft installed. Do you think its worth the risk to use it?

 

[4g63Powered]

There will be people that say they've ran that pulley for 100k miles without any problems, then there are people that say it trashed their engine within 50 miles.

In theory, yes, it can cause damage to your engine. Whether you want to take that chance is completely up to you.

Personally, I like the piece of mind that a dampened pulley gives, plus the performance gains are negligible.

 

[crimsondragon]

You gain like 3 hp while taking the risk that your crank and bearings are taking hits and would possibly need a rebuild after 500 miles. Ask yourself if it's worth the 3 extra hp. You might shave off a .005 second at the quarter mile. Track car, maybe. DD - no IMHO.