i am looking into a new set of cams for my rs and was wondering if i should degree the cams. ive done this to v8s before so im assuming its the same deal with a multiple cam engine. ill just have to do it twice b/c there are 2 cams. am i right??? any help would be great thanks

You have to degree four cams, DOHC boxer. The there is the issue with cam gears.

I was also told the stupid 10' timing belt stretches a bit once you start spinning that sucker and any cam timing done at idle is pretty much off by any significant RPM point. So setting cam timing at 5000rpm or so would be ideal.. but a pain in the ass.

its a sohc so thats 2 cams. i am still unsure . help

what you doing josh? i would degree both cams,

When you degree the cams...please write up a post on how you did it. I'd love to be able to alter the timing of my cams but nobody makes an adjustable pulley to accomplish this.

Jay Storm

obx makes cam ears for the ej engine...don't know if it's useable on sohc, but they're pretty affordable
http://cgi.ebay.com/ebaymotors/OBX-Cam-Gears-for-02-05-Subaru-Impreza-WRX-STi-EJ207_W0QQcmdZViewItemQQcategoryZ33614QQitemZ80454 51624QQrdZ1QQsspagenameZWDVW

Hmm....interesting. I don't see the magnets on the backside but they may just be "stock photos" in the auction. I wonder if the placement and timing is the same for the forced induction and NA DOHC heads..... :devil:

Jay Storm

If you do not have adjustable cam gears.... is there a point?

im sorry i thought you guys knew what degreeing a camshaft was. i dont care about the timeing, i wanna make sure all the #s are correct before i run it. with a degree wheel and dial indicator on p1.

We don't have many cams to choose from for this engine, as far as I know they all use the stock timing marks which are close enough. If you wanted to change the timing of both simutaniously you could easily make a offset key for the crank "gear". I did this as part of the fix when I used thin head gaskets with milled heads
John

i DONT want to change my fing timing.

I think you and I are the only ones who know what it means to "degree" your cam.

http://www.compcams.com/Information/Tutorials/
From the link:
Lobe separation angle is simply what it says. It is the number of degrees separating the peak lift point of the exhaust lobe and the peak point of the intake lobe. This is sometimes referred to as the "lobe center" of the cam, but we prefer to call it the lobe separation angle. This can only be changed when the cam is ground. It makes no difference how you degree the cam in the engine, the lobe separation angle is ground into the cam. The intake centerline, on the other hand, is the position of the centerline, or peak lift point, of the intake lobe in relation to top dead center of the piston. This can be changed by "degreeing" the cam into the engine. Figure 1 shows a normal 270 degree cam. It has a lobe separation of 110°. We show it installed in the engine 4° advanced, or at 106° intake centerline. The light grey curves show the same camshaft installed an additional four degrees advanced, or at 102 degrees intake centerline. You can see how much earlier overlap is taking place and how the intake valve is open a great deal before the piston starts down. This is usually considered as a way to increase bottom end power, but as you can see there is much of the charge pushed out the exhaust, making a less efficient engine. There is a recommended intake centerline installation point on each cam card, and it is important to install the cam at this point. As far as the mechanics of cam degreeing, Competition Cams has produced a simple, comprehensive video (part #190) that will take you step by step through the process.It sounds like the same thing as adjusting the timing of the cam as it can be accomplished with the gears on a Subaru.

I think you and I are the only ones who know what it means to "degree" your cam.

i just had to do this the other day in class, its pretty damn simple. finding tdc can be a little tedious, i think it only took me 20 min or so to degree the cam on a small block chevy motor. we used dial indicators with magnetic stands, there are several methods but i think this way is the easiest. i would definetly do it to your new cams. i think the only info you will need to research is the rocker arm ratio, it should be pretty minimal as there obviously arent any pushrods. myself and a friend just built the 4g63 out of his '03 evo. the little rocker arms in that motor are maybe a little over an inch in length its funny how tiny they are. good luck installing your new setup, should be fun:)

i just had to do this the other day in class, its pretty damn simple. finding tdc can be a little tedious, i think it only took me 20 min or so to degree the cam on a small block chevy motor. we used dial indicators with magnetic stands, there are several methods but i think this way is the easiest. i would definetly do it to your new cams. i think the only info you will need to research is the rocker arm ratio, it should be pretty minimal as there obviously arent any pushrods. myself and a friend just built the 4g63 out of his '03 evo. the little rocker arms in that motor are maybe a little over an inch in length its funny how tiny they are. good luck installing your new setup, should be fun:)


Thanks for the input, but you'll learn there are WORLDS of difference between a Chevrolet and a DOHC Boxer engine. Conceptually, degreeing the cams is the same, but the process / technique is TOTALLY different.

Have I done it on a Suby? No. Have I gone through tthe process in my mind? Many times, and I'll be degreeing mine. I've degreed ~ 100 cams on domestics and 90* V-twins.

FWIW, I would not ADVANCE the ICL on any Subaru turbo engine, period. :)

HTH

S.

i DONT want to change my fing timing.

So what are you going to do if you find out your cam timings are not in spec? Leave it,or get adjustable gears to bring it into spec?