I need to know how to access the cam chain tensioner on my '02. I have ported the intake side of my head (afraid to do the exhaust side, heard there wasn't much metal to carve), and gained some passing power which I sorely need. I want to retard my stock cam timing a few degrees by elongating the holes on the sprocket (done it before on past cars), but don't want to fight the tensioner while putting the sprocket and chain back in place. In exchange for your enlightening me, I will report weather this cheap trick yielded any power improvement... Deal? -Jeffy.

 

I tried a title I thought would get some readers, but got no replies at all (sing it, Phill!), so this time I just put my question in the title. As always, I appreciate the time taken to help me. -Jeffy.

 

I sell adjustable cam sprockets and they work for either top or bottom end power depending on which way you make the adjustment. But since you already took off the head you dealt with the tensioner: it is by the oil filter housing under a 19mm bolt.
Not that the intake porting won’t help but the exhaust side of the head is the more influential side when it comes to making power.

 

In the back of the cylinder block around where the oil filter is. The bolt can be seen after removing the wheel liner.

 

I just had my ultrick cam installed a week ago, I watched the mechanic do it. it is down between the crank shaft gear and the cam gear! He showed me how to reset the tensioner. but there is just one, the other side is just a chain guide but looks just like a tensioner! Not sure if this helps but it is inside the motor under the valve cover!

 

Numbers 3 & 6 in this pic...


http://realoem.com/bmw/showparts.do?...95&hg=11&fg=25

 

You sooooo on itgreat find/post.

 

It requires a 19mm box end on the MCS but the MC has room for a socket. With the valve cover and header removed there's room to access from above, be careful, the cap head is soft.

 

I had said that if you all helped advise me, I would report my results, good, or bad. I succeeded at removing the tensioner, then used a dremel tool with cut-off wheel to remove 2mm from the back side of the slot on the cam sprocket which allowed me to retard the cam a few degrees(stock cam). I drove the car this evening and am happy with the results. Previously, my power for passing was not satisfactory despite having ported the intake side of the head(did notice improved performance after that, but needed more). Standing starts were okay even with the cvt. Now, my standing starts are still fine for jumping out into traffic, but I get a nice surge of power from about 4500rpm to stock shift point of 6000rpm. The gain in power is maybe 10 horsepower, but I'll take 10 free ponies! The computer had adjusted to a nice smooth idle in about 10 minutes. To me, this mod is a win-win. No money spent, no ill behavior, and a gain in power where I really need it. When I first bought this '02, I felt that the stock passing power was seriously lacking, and work would be needed to rectify that. I now feel that passing performance is actually good, though my car is still no rocket. I will continue with my hobby, which is making it faster. Now I have a little power to go with my handling! -Jeffy.

 

any pics of the grinded sprocket don't really know what you talking about

 

Look at the pic posted by Parts Man. The slot is at the top of the opening in the center of the sprocket in that picture. The aft side of the engine is the side with the chain tensioner. What I did was grind 2mm off of the aft side of the slot. I didn't use a degree wheel which would have been smart, but the result is good, so if you want to duplicate my result, use feeler gauge blades to measure the size of the slot opening before, then after grinding(use restraint!), check with feeler gauge blades again. Also remember that I ported the intake side of the cylinder head, so I'm not sure what results you'd get with stock ports. I do know that if I could rev it to at least 6500rpm before the cvt shifted, I would get better accelleration as presently modified. I would buy a chip/program to accomplish this, but they are too expensive for me, and nearly all mods have to be free or really cheap for me to do them. On the bright side, you can learn from my cheap tricks, and not have to sell the idea on your wife/husband(except the "why are you taking it apart when it is running just fine as it is?)! Have fun, but be careful! -love, Jeffy.

 

See the post I made titled "Where's the cam chain tensioner?". I thought I should make this mod known since it's free and works. I'm not sure what kind of gain you would get with a stock, not ported head, but mine has the intake side done by myself, and I have found that retarding the stock cam will give more high rpm power without losing low end- if you do it like I did, which is, with some restraint. My car is an '02 with a cvt, and the mods both increased my power without causing any ill behavior. With a cvt, you know I had the least accelleration of any Cooper setup, and despite that, my mods have improved accelleration and it only took some mechanical ability (I'm an airplane mechanic), but no money. I will continue to come up with mods that cost nothing but time and post them here. Even if you are a rich and famous star, why spend money needlessly? Use the money saved to buy some shoes or something. -Jeffy.

 

I cut and pasted "Where's the cam chain tensioner?" into the thread searcher but nothing came up. So to make life a tad easier for all y'all, here's the link.

https://www.northamericanmotoring.co...ad.php?t=85272

 

how did you retard it? this is interesting

 

very cool jeffy! I'm not brave enough to do this mod however ^__^

it seems like it could potentialy lead to expensive parts..

 

and guess what's sitting on my workbench? The cam gear!

But what I don't know is if an advance is really what's needed in all cars, or if there's slop in the manufacture....

Matt

 

GTT offers a vernier cam gear that you can adjust and play with... Thing is that without access to a dyno, tuning would be seat-o-the-pants only. I've also heard that when you advance the timing, it's a good idea to mess with the thermostat and cooling (e.g. swapping to an electric coolant pump and setting it to a specific temperature). MINIMania UK has a couple beastly track Coopers where they've done extensive mods - I believe one of them is capable of 182 bhp now.

 

I retarded mine, not advanced. My results I prove by accellerating from a standing start to a finish line and see what speed I attain. Remember, this is a non "S" car. Another thing to consider is that it's only 1.6 liters displacement, so trying to make it faster with low rpm torque is a waste of time. I'm going with the Formula 1 method (to a much lesser degree), which is to take the tiny engine and rev it up to make power. With the cvt, the ratios are close enough that I stay in the power band-now that I actually have a power band. Do your own thing- all I know is that my car keeps getting faster. -Jeffy.

 

I took 2mm out of the aft side of the sprocket's locating slot(where it is held by the roll pin in the cam shaft). I decided to use restraint on the amount of retard applied and won. I knew that if I removed too little to make a difference, no harm done. I also knew that I might get what I want-which I did. Granted, this may not be the ideal index for the stock cam, but I am satisfied enough with my result to not want to change it any further. -Jeffy.

 

I thought the only way to get 10 hp for free was to put some stickers on the windows?

Seriously, interesting mod.

 

It looks like there were at least three threads created by the original poster on this topic. All those threads have now been merged.

 

obviously isnt working for me

 

you turned the cam clockwise more yes? therebye opening and closing valves sooner as compared to the crank .yes?

 

I turned the cam counter clockwise as viewed from the right side(passenger side in the U.S.), causing the valves to open later relative to crankshaft position. It's actually a pretty old trick- Americans have done this stuff forever. Depending on what kind of engine behavior is desired determines which way to turn the cam. Nowadays, cam designers have it all sorted out according to the engine and vehicle application- you'll find that a good shop that sells high performance cams will ask you lots of questions about the car, engine, transmision, and final drive ratio before recommending a cam and how it should be indexed. In my application, retarding was the right thing. By the way, I now have over 300 miles of driving after this mod. I'm glad I did it- I hated trying to pass people with too little passing power. You ever get someone step on the gas while you're trying to pass them? Sure you have. Now I can still leave them. -Jeffy.

 

I'm sorry about the mess I've made, but now the title reads "Cam chain tensioner mod for 10 free horsepower", or close to that. The problem with that title(plus me mis-spelling tensioner)is that the tensioner is not what gets modified but instead the cam sprocket does. Anyone reading the other title will probably dismiss it as "This guy is an embarrassment to himself-you can't gain power by modifying a cam chain tensioner!". I feel that people should at least read the thread because it's a rare thing to get more performance without having to buy anything. -Jeffy.