rayaapp2 Posted April 5, 2011 Share Posted April 5, 2011 Alright guys, My head hasnt been the straightest in the past month as Ive been on pain meds so please excuse any stupidness I may blot out or if the answer is apparent as the nose on my face. So what has happened is I installed a Fidanza Adjustable cam gear before I needed meds. So Im fairly sure of my work. I had my buddy come over and button the covers up last night. Everything is set straight up until I get to dyno it in. So after fitting the covers we started getting a oscillating humming noise. It was apparent it was near the top of the engine after a minute of running. I was hoping it was the alt belt. Anyway, so I had him pull the top timing belt cover off again. We re-installed the CAS with some washer spacer to prevent it from rubbing the cam bolts on the timing gear. After re-starting the engine I could see the belt 'shifting' with the noise across the new timing gear. I applied a little bit of pressure with the round end of a hard screw driver to add tension and the noise quieted down. So we thought about it for a bit and decided we had to pull the bottom front cover off and adjust the tension on the timing belt up a bit. So an hour later we are ready to start again and I have tightened up the tensioner a bit this time after a couple revolutions of the engine to be sure the slack was accounted for. The engine still starts and the oscillating humming noise is still there. So here is where I go 'what is different'. I grab the fidanza adjustable cam gear I still have in the box, because I got a pair of them for a good deal and check out the extra gear I did not install. I grabbed my stock exhaust cam gear at this point an hold them next to each other. The stock cam gear is squared the same as the belt shape. The Fidanza gear has the same general square shape but is cut in a semi-circle instead of the square shape. The belt fits the semi-circle but there is a gap at the bottom of the belt teeth to the cam gear. At this point I am speculating my belt is tight enough and that the shape of the Fidanza gear is causing the noise much like knobby tires on a road surface because of the air gaps from tire siping. The part number on the Fidanza parts are for RB and I confirmed it via phone with Fidanza even before I installed it. So its not like the gear was cut for a belt with semi-circle teeth instead. Should I be affraid of the supercharger like noise it is making at this point and continue to look for something that was incorrectly installed or does my conclusion sound valid? Thanks for the extra brains on the matter guys. Quote Link to comment Share on other sites More sharing options...
jakeoster Posted April 5, 2011 Share Posted April 5, 2011 Maybe the flawed design is the cause of the reasonable price? Quote Link to comment Share on other sites More sharing options...
jasper Posted April 5, 2011 Share Posted April 5, 2011 I have never seen belt tooth profile NOT match, gear tooth profile. In stock form, if the belt is OVER TIGHTENED, things get noisy. In my opinion, the gear is not compatible with the current belt. Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted April 6, 2011 Share Posted April 6, 2011 I would put the OEM cam belt gears back on until I researched the profile discrepancy Try Google and see if others have had this problem. I know HKS had a set for RB's a while back that had these symptoms... they changed their design. Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted April 6, 2011 Author Share Posted April 6, 2011 I would put the OEM cam belt gears back on until I researched the profile discrepancy Try Google and see if others have had this problem. I know HKS had a set for RB's a while back that had these symptoms... they changed their design. I gave Google a whirl. Pretty much everyone has been saying that the "belt is making noise because its breaking into the new gear". Im not sure I trust any of that. Fidanza stands by the product saying they have not received any complaints about it in the 2 or 3 years(I cant remember for sure) they have made it. The car was driven around a little bit today and the noise is lessening and not constant anymore so there might actually be truth in what the other website ppl are saying. Its gonna get pulled back apart though to be sure nothing weird is happening and Im seriously considering putting the stock cam gear back on for now. Ill get some pictures up later if I have a chance. Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted April 6, 2011 Author Share Posted April 6, 2011 Fidanza just called me back again. They are saying that I have the right cam gear, but its not suppose to have round cut gears. I bought them third party, but since I have all the original packaging and parts they said they would take them back and re-send me out the corrected parts OR if they do not have them in stock find me and send me no charge replacements. Talk about customer service... definitely going to buy other Fidanza parts if this is how they treat(pun intended) customers! Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted April 6, 2011 Share Posted April 6, 2011 Good to hear they are replacing them. If all company's were that responsible... huh? Quote Link to comment Share on other sites More sharing options...
ZT-R Posted April 6, 2011 Share Posted April 6, 2011 i was thinking hard about those, ended up geting tomei ones though. i had AEM on my honda and they completely disintegrated. i sent them in to aem and they "ran metal tests" and said did they didnt know what happened. they did send me 2 new gears but thats moot after the valves dropped and nailed all my pistons and bent 2 rods. Quote Link to comment Share on other sites More sharing options...
jakeoster Posted April 7, 2011 Share Posted April 7, 2011 Hey cool! That turned out good. Looks like I'll be buying Fidanza in the future. Quote Link to comment Share on other sites More sharing options...
rayaapp2 Posted July 8, 2012 Author Share Posted July 8, 2012 Fidanza never corrected the issue. They will not be as far as their tech and R&D departments stated ever be recutting the tooth patterns on their cam gears. I do not know if they are still offering this product with the defective teeth, but I hope they are not. I finally received a refund last month for the gears. Sad end to the story. In short do not buy the Fidanza Cam gears for the RB series engine until you are certain they have a revised square cut tooth pattern. Quote Link to comment Share on other sites More sharing options...
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