Ok, I've been kicking the idea around about swapping some NA cams into my T-5R. Done a lot of poking around and still have a few questions because things are not crystal clear.

I contacted my local Volvo shop and they told me that the PN on the '93 850 crossed through all of the 850 NA years so he believed that Volvo sells the same cams for the '93 to people that own '97 850's. That makes me believe that all of the NA cams are the same, or at least they now are in Volvo's eyes. They also informed me that I could NOT purchase them from Volvo, they no longer sold them.

Anywho, I picked up a pair of NA cams from a '95 850 that was in the jy today. I left the sprockets on them and walked out the door with them for about $35. The jy was having a 1/2 off sale for people that has their membership card. The intake cam PN: 9146232.PLI; the exhaust cam PN: 3547905.PFE.

Now for the test questions... I have read that some people just install the intake cam. Not really sure why, that would create a situation where you have mitch match cams. So I'll install both of them. Here are my questions:

1. I read that the timing needs to be adjusted advanced/retarded on the intake and exhaust cams. If I leave the cam sprockets on from the NA car, do I still need to adjust timing?
2. When timing is adjusted, which way is advanced and which way is retard? Clockwise adjanced?
3. The timing belt cover on the motor, over the intake cam, has knotches on it, are those used to adjust timing?
4. If I install a timing belt and the marks are aligned with the cover, assuming that the cam sprockets have never been adjusted or loosened, is that considered the baseline and you adjust +/- 2* to 4* from there?
5. How much adjustment should I make to get the benifit of the NA cams?

Once I learn which direction is + and which is -, I plan to make some kind of compass plate that I will screw on the back of the cam. It will have a hole in the middle and marks with degrees on it. The marks will likely face the front of the motor and the plate (plastic or some other stiff material) will face the front of the motor. Then I'll put a tool through the hole, loosen the bolts on the cam sprocket and adjust the timing on the cam. Maybe I'll make the custom compass out of a cd disk and use a protractor or my compass torque tool (that I use to torque head bolts) to make the markings. All I really need is a few marks and lines for each degree. No more than 90* of marks (not even that many if I use a rachet wrench).

If there is a better way please let me know. When I pull the cam cover I usually DO NOT use any tool to hold the cams or keep them aligned. I usually just align them with the cover set in the head.

 

ipd sells cam adjustment plates if you're interested in going that route.

As for where you want to be: I'm running +2 degrees on my intake and -2 on my exhaust - both are 93 n/a cams. Thats with ARD green tune.

Cams turn clockwise if you're looking at them from the passenger side of the vehicle towards cam gears.

Hope thats of some help.

 

Do you know what their PN's are? I have not seen a '93 in our jy's in a long time. Maybe never.

 

3547600 Intake
3547601 Exaust

 

Interesting, very different. I wonder what they are on my T-5R?

 

I just check iPd's website and they have a timing adjustment tool. They recommend:

Intake Retard 4*
Exhaust Advance 5*

http://www.ipdusa.com/files/product/...STRUCTIONS.PDF

Has anyone gone with those settings? I do NOT have a tune, just a non modded T-5R.

Their instructions seem simple to follow and quick to do.

 

I'd probably go with their recommendations then - mine came direct from ARD, but that's with the tune.

 

Interesting, I think we answered all of my questions.

 

Oh, I forgot to talk about what the new cams change... Ok, the compression of the NA motors is 10.5:1 and the compression of the 2.3 T5 motor is 8.5:1. Does the cam change alter the compression ratio at all?

 

if it does, id think its minimal. it might drop a VERY slight amount due to the cam holding the valve open a bit longer. That being said, I doubt it's even noticeable.

 

they shouldn't change compression, what they would be changing is the RPM. how quickly it'll rev, how far it'll rev and where they'll supplement power...
so, for instance, when i did the cam in my turbo skyline, i was able to run less boost and have more power earlier on in the rev range, i went from running 13psi to get 200rwkw to 11psi to get 210rwkw and it was getting into a nicer power curve a few hundred RPM before it was with the stock cam...

let me know how you go, i've got some cams sitting to go in on my R...just been a bit lazy :P

so, pictures are right up please

 

So the main benifit is power curve change. The GLT's get their peak torque at 1,800 rpm's where as the T5's don't get theirs until around 4,500 rpm's.

I actually believe that our GLT get's to 35 quicker (it burns tires easier) and maybe even 60 about the same amount of time. It's after 60 mph when I can really tell the difference between my R and the GLT.

If the NA cams change that, it would be very nice.

What kind of pics do you want to see? I may already have them.

 

Working on my cam swap today. (put rspi's belt tensioner tool to work).
I have a question on the cam gears though. I have been reading countless threads on cams swaps, and can't find this answer. Do I use the NA cam gear or the turbo cam gear on the intake cam. The exhaust gear has the timing mark in the same spot for both NA & turbo, but the intake gears are 2 notches different from each other. I have read many posts that say they are the same gear. While the physical design is the same, the timing marks are different. Any input from those who have done this?



I plan on buttoning it all up tomorrow and hopefully getting over to the dyno again before the ARD green goes in so I can have numbers on a cam change.

 

Here is the IPD cam guide and the settings for N/A cams.

 

I do have the cam timing tool, but I am curious as to which intake sprockets that I use, the NA ones or the turbo ones. The factory timing mark is in a different location on each of them.

Great detail pic btw!

 

The sprocket notches line up with the plastic cut outs. So, with your cams in the right position you should be able to get the right sprocket by matching the cam bolt pattern to the notches. Hope the picture helps.

tech tip: a little shot of spray paint on the sprockets before you disassemble helps you line up the cam right where they were when you started.

 

Thanks for the input boxpin. Got it all buttoned up this morning. Runs like a champ. I used the gears from the NA car for the record. Should be able to hit the dyno in about a week to see what the cams did. I did a baseline run a few days ago before I started all this fun. I will be installing the ARD Green on the same day, but after I get a couple runs with just the cam swap.

 

Good to hear you kept the NA cam sprockets. Here's the deal with installing the NA cams... If you simply drop the cams in there will be very little benifit if you just install them without adjusting the timing. BoxPin was trying to show you how iPd suggest adjusting the timing "correctly" to receive the benifit of the NA cams. Because the cams have a wider/deeper lobe, the "overlap" of the opening of the intake and exhaust valves need to be adjusted to change the power curve to receive the power benifit. Here is the link to iPd's cam tool and their PDF instructions to help you understand what and why the timing needs to be adjusted.

Cam Timing Tool

 

I kept getting hung up on the fact that the marks were in different spots. I finally got it through my skull that the gears are slotted so put the "mark" where I need it. Thanks to both of you for the input.

 

Here is the deal, the cams have the slots on the back of them. The motors were put together at the manufacturing plant, timing set correctly at the plant with the rear of the cams locked in their correct timed postions. Then the cam sprockets were installed and secured with the belt installed. I'm sure turned and the rears of the cams were re-checked. Then the lines were etched into the cam sprockets. So the marks are likely not at the exact spot on any set of sprockets. You can lock the rear of the cams timed with no advance or retard, purchase a new set of cam sprockets with no marks on them, install them and etch a mark in them and the new mark will be perfect. You can pull those cam sprockets, spin them around 30 degrees, re-install them on the next set of bolt holes and the marks will look different when timed correct.

I say all that to say this... Don't be hung up on where the marks are in relation to peaks and valleys on the sprockets.

What I would suggest is, if you adjust / change the timing, etch or somehow mark the sprockets as to how far the timing was adjusted.

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Now that I written all of that, I can't stop my mind from turning even further. Adjusting the cam timing changes overlap and turque curve. Now I have read/heard that the computer adjust timing for the car so it will run smooth. Will the computer try to correct for the physical adjustment of the cams that you just made?