any one?

 

Bueller?

 

spgproject has.


I think you lose a bit of tq down low, but gain some hp up top.

He has 250 whp and about 220 wtq.

 

an 85 exhaust cam and a n/a intake cam seems to be the best stock combination you can use and what I have in my car. It works good if you have enough boost and fuel.

 

are the 85 exhaust cams in particular different from other years?

i recall reading that the N/A cams have a more 'aggressive' lobe, but i honestly don't know what this means exactly. is the lobe wider, holding the intake valves open longer?

what about the exhaust cams? i understand that, on a turbo'd car, if any valve mods are to be done, that larger intake valves should be used while maintaining exhaust valve size. i believe you would also want the intake valves open longer to allow more air into the cylinder.

i understand that the exhaust valve size should be maintained to keep exhaust velocities up, but what about the cams? would one be looking to open the exhaust valves a little later, hold them open longer? shorter?

i probably ought to see what info i can find in other posts.

 

I wanted to find some better info rather than just randomly saying the 85 cam is "better", here's a post from ubipa a while back I found on the TSN performance bb comparing cams.

Every other inlet lobe has 2mm less lift, which is designed to create more turbulence. The turbulence is to mix the air and fuel better. The downfall is it limits the flow, preventing more fuel and air from getting into the cylinder. From 86 on, the cylinder heads were casted w/ a design to create more swirl which in effect creates turbulence w/o limiting valve lift.
The other difference is that the matched 85 cams have a shorter valve overlap of 26 deg compared to 29. The shorter overlap insures more boost pressure is staying in the cylinder and not escaping through the exhaust. Actually, a set of performance cams for a turbo should not have more than 20 degrees of overlap.

Only the exhaust cam w/ it's 56-10 grind seems to be of any advantage. With a properly ported head there should be no need of the 85 intake cam. A small problem w/ using the 85 cam is its small duration compared to the 252deg intake duration, less new air/fuel will be able to get in. A better performance match of SAAB cams would be a 90-93 9000 intake cam w/ the 85 exh cam. They have an identical duration w/ only a 23 deg overlap.

B234 Intake has more hp's on highend than other cams (retard 3deg)
85 B202 Exhaust has more low end (3deg advance from b234)

there are some other points made in a few other posts I found over at SC, but the general consensus is that a 9000 n/a intake cam matched with the 85 exhaust cam will give a noticable performance increase at higher revs, even if all other factors stay the same. Low RPM smoothness and idle quality are slightly affected but it's very marginal.

oh, and these also work with T5 & T7 cars too, but expect it to change the VE of the engine.

 

I wanted to find some better info rather than just randomly saying the 85 cam is "better", here's a post from ubipa a while back I found on the TSN performance bb comparing cams.

there are some other points made in a few other posts I found over at SC, but the general consensus is that a 9000 n/a intake cam matched with the 85 exhaust cam will give a noticable performance increase at higher revs, even if all other factors stay the same. Low RPM smoothness and idle quality are slightly affected but it's very marginal.

oh, and these also work with T5 & T7 cars too, but expect it to change the VE of the engine.

meaning... it's going to make my car sound meaner? shweeet!

 

85 exhaust is what i am putting in my vert

 

is the 2.1 91-93 900s intake came the same as the 9000 2.3 90-93 intake cam?
and as far as the 9000 intake came are turbo and non turbo the same?

 

this is a very informative thread. What if you used the 9000 intake cam but kept the stock exhaust cam? I don't have an 85 exhaust cam.

 

sticky?

great post, jeff.



and yes, it does seem to be more of a hp than torque setup. i thought that was mostly due to me having a larger, laggier turbo, until burnsides auto 9k w/td04 went up and made more hp than torque (he has this same cam setup). it was quite surprising.

does anyone remember what his numbers were?

 

So, is (91 -93 900 S) intake Cam the same as a (90-93) 9000 N/A intake Cam?

 

B234 Intake has more hp's on highend than other cams (retard 3deg)
85 B202 Exhaust has more low end (3deg advance from b234)

so, in this setup, the exhaust cam would be TDC according to flywheel location, whereas the intake cam would be setup with a 3 deg retard from TDC?

i figure 3 degrees off would be about 1 tooth, is this correct?

i dont think the 2.0 intake cams are the same as the 2.3... i could be wrong.

 

are the '85 c900 exhaust cams unique to that MY, is there a production date that i should be looking for? i know that many '85's are made in '84, but what is the cutoff for manufacture date? mid/late 84 thru early/mid 85 is what i figure i would be looking for.

also, the 9k cams... 90-93 9000 N/A exhaust cam. i can figure production to be mid/late 89 thru to early 93?

i am adding parts to my weekend shopping list. let's see what i can come up with.

 

pretty sure it was only model year 85 16v turbos that had it, the head and intake manifold are completely different on the 85's, like if you look at an 85 and 86 side by side you can clearly see that theres a difference. for the 9k, it basically has to be a 2.3 with the "longblock" engine. so before 93.5 i think is the cutoff for those.

Paul

 

If the head they are coming off of has oil supply tubing running into the tops of the cam bearing caps, it's an '85, all other year C900 and early 2.3 9k's had oil supply passages integrated into the bearing caps.

You should be able to search the p/n for the '85 exhaust cam on Saabnet or one of the British sites, it's been discussed a lot.

Best,
Drew

 

If the head they are coming off of has oil supply tubing running into the tops of the cam bearing caps, it's an '85, all other year C900 and early 2.3 9k's had oil supply passages integrated into the bearing caps.

Not true. My 88 C-900 turbo had the upper cam oil feed pipes, as did my 86 900-T. 1989 was the changeover year for that one.

 

Woops! I have only ever had '85 and 90+ parts! Thanks!

 

Ok, I just picked up xassh's 85 Exhaust cam. The consensus is that I want a 91-93 N/A 9000 Intake cam to match it, right?

Would I be lucky enough to score one of these in a local junk yard?

 

Would I be lucky enough to score one of these in a local junk yard?

If the junkyard has a 1991-1993 n/a 9000, then yes. ;-)

 

Every other inlet lobe has 2mm less lift, which is designed to create more turbulence. The turbulence is to mix the air and fuel better.

this is due to the 1985 16v heads having identical (or nearly so) intake runners

the different intake cam lobe heights makes it very easy to confirm, at the parts yard, that you do indeed have an '85. it is not always easy to cross reference part numbers when you are away from home... i never think to write them down before i go 'shopping'

 

you guys are wasting your time messing with these cams when you could get a modified street profile made at a cam place from your old cam for like $150. If you get the cam welding done so the base circle is the same size it will drop right in and since you have hydraulic lifters there is no adjustment of the valve clearances.

That 85 cam is still a 252 duration (which notably the 86 and up cam is a 254 duration). You could bring that exhaust cam up near or over a 300 duration depending on how serious you are.

The cams for a turbo car would best be done in pairs so you can work with the cam place to get the proper overlap for a turbo engine.

 

yes, but 85 cams are usually free-to $20, not $150. And I doubt I could find anyplace that would do it for 150 anyway. What's Nick T charge for his, $750 or something? :lol: Not saying THAT is reasonable (I think it's crazy) but when you start talking custom cams most places start talking kooky money. 85 turbo cams as well as n/a cams can be found in junk yard cars, it's a stock cam set up, it's cheap and is better than what these cars had stock... that's kind of the point.

 

its a waste of your time

the duration is less, so any potential gains must come from a difference in overlap, and i bet its really negligible.

If you can't find a weld and grind service for 150 on the east coast (which is bullshit) then call delta cams in tacoma, wa at 1.800.562.5500 or email sales@deltacam.com. They ship stuff all the time.

I understand the value of free parts, but I don't see the 85 cam being a godsend either.

 

read the 7th post here, hardly a "waste of time" I would not call a mod a waste of time when it costs basically nothing, You can feel the difference in with no other mods, and can show dyno results that are an improvement. I am not saying it's as good as custom cams cause they aren't, but it ain't no waste of time :lol:

 

also, the 85 cam / 2.1 intake cam will still pass emissions. many people here still have to pass the emissions dyno test, and sticking in a high lift cam is a sure fire way of getting a FAIL sticker in your screen, and having to pay some grungy mechanic to replace $300 of random engine components each year you come in for inspection and the car fails again... Thankfully my cars are registered in a county that only requires a gas cap check (also why I don't have a cat), but any cars registered near Pitt or Philly PA are not so lucky.

 

We need to find out why this cam is better because it will help all of us choose the right profile in the future for a custom cam..

the 85 cam opens at 56 deg BBDC, and closes at 16 ATDC, making the duration 252

the newer cam opens at 61 deg, closes at 13, 254 duration.

the 2.1 cam opens at 16 BTDC, and closes at 44 ABDC. 240 duration.

The 2.0 cam opens at 16 BTDC, and closes at 56 ABDC. 252 duration.

all of these have the same lift, 8.65mm.

So I have a few thoughts on this. First of all it looks like the only advantage comes from MORE overlap. Which is odd because I've heard that less overlap is better for turbo cars so you don't 'blow' your mixture out the exhaust. I think in this situation it creates a bit of a scavenging effect from the exhaust slug of air heading out, pulling the intake in.

What I don't understand is the 2.1 intake cam. Either i'm looking at the wrong specs or its the opposite of what you'd want. Anyways we should get to the bottom of this because its always helpful to understand what is happening in your engine.

www.900aero.com has all the specs in their tech section.

 

85 exahust cam part number

so i pulled the cam out of an 1985 turbo saab, but the part number does not match any on 900 aero.com

my part number is 750921.

900 aero list the 85ex cam as 750219? is this a typo? or do i have a different cam??

anybody know where this cam came from?