I just got an Underdrive Pulley for my b16.. I havn't ever messed with an underdrive pulley but i've done a lot with the rest of the honda motors, so I was wondering if this is going to help my motor out any or if it is going to be normal?? I've searched, just can't find it.. (i'm not use to the search engine) Just wondering cause if it's not going to be anything noticeable then I'm just going to save it for the LS Vtec motor i'm going to be building..

Thanks.. Justin..

 

there's a big debate over whether they hurt your engine or not.
if your engine isn't internally balanced, then an underdrive pulley will be bad for the engine and could cause problems later on. Honda pulleys are harmonically balanced.

 

I have always heard and been told not to replace a honda crank pulley with an aftermarket one cause they arent balanced correctly.

if you had your whole bottom end balanced with the pulley it would work out nice... but i would stay away from it. just my .02

 

I put one on my 05 Scion tC, The OEM Was Harmonically Balanced the After market was not.. 2 Years 80k miles and it was fine.. And i did notice the differance. Oh and i ragged the **** out of that thing.. I was at the track almost every other weekend. Just my 2 cents.

 

yea but are you sure the tC engine wasn't internally balanced?

 

i don't think it was.. I'm not to sure i'm trying to search now to find it.

 

And... There not.

 

ok, just making sure

See this is where the debate starts. Some people have problems with them, some people don't. I leave it at that by saying, you either get lucky or you get unlucky. IMO, this is a risk I would not be willing to take.

Another point is that we're talking about Honda engines. I'm not sure if Toyota engines react differently to an unbalanced pulley or what. If anyone knows the answer to that, chime in, because I would be interested in hearing it.

 

I dunno, But i will tell you this.. Even tho i had one on my tC and liked it.. I wouldn't put one on my Del Sol.. Maybe because i care about my Del Sol so much? I dunno.. Just saying lol

 

iv had mine on now for like 20k and beat the hell out of my motor and it still runs strong so i would say go for it ...

 

Just get a CTR N1 pulley

 

yeah I was looking that the CTR pulley.. just got this one from a guy off his Gsr.. trustdestruction what exactly were you meaning by could cause problems?? what is a downfall of it?? just wanting to get everything straight.. ..

 

If the pulley itself is balanced, you might be ok with a b16.

Even if the engine is internally balanced, it does not mean that it will be fine with an undamped crankshaft pulley (and most lightweight pulleys do not have integrated dampers). It is an issue of torsional vibration.

Since the b16 has a relatively short stroke and a lighter crankshaft, the critical frequencies will likely be at very high speeds, if not beyond the usable powerband. I'm not advocating undamped pulleys, but I doubt that you will have issues in this application.

 

So would it be a noticeable difference??

 

I wouldnt use one underdrive crank pulley unless it's one with a harmonic balancer, all other pulleys you can switch to underdrive like Alt and PS, but i wouldnt use a cheap crank pulley, I've herd more bad things from people using them because the engine spins so high and with no balancer **** hits the fan, unless you get a ATI i think there called and like 300 then your set and they make power, look into those one's

 

It is not worth the risk. The few HP you would gain is simply not worth ending up on the darker side of the debate. If you want more power, then do what is known to work. It's like every other small bolt-on that is "suppose" to make power. In this case, it likely does free up parasitic load, and create a faster reving engine. However, with the debate, and horror stories, it just doesn't seem worth it.

Save your money for a turbo or supercharger. Then you will know you are getting more power reliably.

 

I am more for an NA motor, I'm not into the turbochargers and superchargers.. I like to put pistons and such in the motor.. and doing small stuff with them..