ok we have a 1995 LS engine, i made a post a fwe weeks back, about the timingbelt jumping a tooth. I had set the tension on the belt like i always do on LS and CRV engine, reved the engine up and the intake cam jumped a tooth when the engine went from accelerating to decelerating. so i checked compression and numbers were all good, reset the timing this time i made the belt tighter. Engine ran great. did some tuning came back and it was alittle noisy. checked the valve clearance and everything is right on. checked timingbelt and i noticed as the engine rotates i get slack between the cam gears when a cylinder builds pressure and it then decreases. the belt also has atleast 1/2" deflection on the longest distance. Do i need an aftermarket timingbelt, currently running an OEM belt. do i need cam gears? or both? Tensioner stays tight, and i have the belt as tight as i can get it. when i tighten the belt, i make it tight between the cams, then rotate the crank cc to put all the slack on the tensioner. i then use a prybar or plyers to move the tensioner to remove any slack and then before tighting i take the pressure off the tensioner pulley.

any help would be great. car also gets a very loud drive train noise when the belt is hitting the slack. its almost like the springs are so tight the belt can't keep up with there rotation.

 

If its to tight it will have a loud whinning sound, Yes with those cams you need to dial them in so get some aftermarket cam gears of your choice, did you adjust the valves when the motor was dead cold? make sur the cam gears are at tdc centered and reinstal the timing belt and se if it gets better or worse.

 

engine was cold. no loud whinning, ive had a belt to tight on a civic before so i know the noise. cams were centered, and ive already pulled the belt twice thinking i had something wronge. other members have run the 402t cams on stock gears and had good sucsess why does mine have issuses. i get very loud valve train noise when the engine goes from up reving to down reving because the belt tension seems to change. im starting to wander if my cam gears are bent or something. at start up valve train noise is loud, but after it warms up it runs smooth and quiet.

 

How old is the belt? I had similar problems when my belt has stretched unevenly. I run the 402T cams and haven't had any problems with them yet.

Have you checked for coil binding? My brother had a problem with coil binding that caused similar problems.

 

belt has around 5000-7500 miles and was only used for one year.
Coil binding? are you refuring to the distributor bearing going bad? I'm going to pull the distributor and turn the engine over by hand and see if the uneveness in the belt goes away.

 

I'd still try replacing the belt, it's cheap and simple. Sometimes they stretch and sometimes they don't. Mine wasn't that old when it got stretchy.

Coil binding refers to the valve springs. There are cases where the springs will be fully compressed by a bigger cam, causing them to bind and place stress on the cam and the timing belt. On my brother's motor the cams (Crane Stage 2 cams) were just a little too tall for the valve springs. It actually ran fine for thousands of miles, but the timing belt was a bit jumpy, and one of his cams finally snapped.

 

that i don't want to happen. ill check to see how compressed each spring becomes, we installed the supertech spring seats with the springs so hopefully that is not our problem. ill more than likely order a new timingbelt very soon. Is OEM the best option or is there somtehing more performance oriented?

 

Did you adjust your valve lash to your cams specs?

 

no valve lash specs came with the cams, and i haven't found any info on the website either. anyone know off hand what the specs are? i set the lash to factory b18b specs. i may have to call crower today after work and get the specs.

 

It's been a while since I did mine, but the specs were bigger than stock. .007 and .008 maybe? I'm on the road so I can't go look at my cam spec sheet, but try calling Crower and see if they can help you.

 

I am having the same problem with my crower cams. I have skunk 2 cam gears and I had to adjust them alot to line up the holes on the head and cam to put the punch that holds the cams center.

On cold start up it sounds like I have a knock or the belt is slapping something. As soon as it warms to about 140 degrees it sounds quiet as a church mouse. I am thinking my intake cam gear is a little bent. I am going to put stock cam gears on next week and see if that takes care of it. My belt is new.


keV

 

Supertech claims the springs will have no problems with the 402-T cams. So ive got a new T-Belt to install and hopefully that will fix the problem. otherwise i will be looking for a good set of cam gears. It seems like the whole problem is in the intake cam. when it turns the belt is tight, but then when the spring tension come off of the compression stroke the cam clicks forward faster than the exhaust cam causing slack in the belt untill the exhaust cam catches up.