View Full Version : 3L Cams
Dom1013
06-09-2007, 06:48 PM
Will 3L cams go in 2.5L heads? From what I understand they give more low end torque...
Yes, they will "go in" the heads, but you'll need new crank sprockets, chains, and tensioners since the 3L cams' gear pitch is smaller than the 2.5L cams. I read somewhere that the later 2.5L engins have small-pitch chains- Someone check me on this?
Haven't had any definitive info (read dyno plots before/after) cross the wire about better lower-end power.
Dom1013
06-09-2007, 10:24 PM
okay, figures...guess that's for another day unless someone can verify the size of the gear pitches...probably not, seems like there arent many people that have done alot of serious performance mods to 01-02's.
StealthyWeasel
06-17-2007, 06:32 PM
01/02 has narrow band timing components.
I have 3L cams and timing with 7k on it if you're interested, but im 99% sure you should be fine if you just wanted to add 3L cams.
In fact, it would be more work to do SVT cams because they run off wide pitch timing.
j-keezy
08-02-2007, 03:09 AM
so your saying you have 3l cams not svt or am i just stupid and if so them your also saying you dont have to change the chain or anything.
Blackcoog
08-02-2007, 09:18 AM
so your saying you have 3l cams not svt or am i just stupid and if so them your also saying you dont have to change the chain or anything.
He's saying he has a set of 3L cams for sale which have 7k miles on them. He's also saying that for the 2001+ Cougars you can switch in 3L cams without having to changes chains or timing equipment.
The earlier Cougars and SVT Contours use larger pitch chains and gears. If you want to use the larger pitch SVT cams and you have a 2001+ Cougar you also need to install the larger pitch chains and timing equipment.
j-keezy
08-03-2007, 03:00 AM
How Much Power Would They Make
papatedroach
08-03-2007, 09:52 AM
I dont think anyone has done it, but here are all the engine and cam specs, curtiousy of DemonSvt. So you can see the differances.
Engine and cam specs (http://home.kc.rr.com/newshore/Cars/Info/EngSpecs.html)
edit: from a quick look at the cam specs, it seems like they would increase your bottom end, but your top end will suffer. They open earlier, but have a shorter duration than the secondary valves. 3L's dont have secondaries, all the valves are used all the time.
more motor info (http://home.kc.rr.com/newshore/Cars/Info/Info.html)
Blackcoog
08-03-2007, 12:17 PM
It would definitely give you a more usable power band but your top end would be pretty useless. It's probably a good thing for a daily driver. For someone looking for all out max hp SVT cams would be the way to go.
j-keezy
08-10-2007, 04:12 AM
do you think any gain is made in the top end with the 3l. i have an atx and i wanted to put cams but dont know wich is better thats why i ask
Top end power: SVT cams FTW.
Low-end torque: 3L cams FTW.
Not tested: 3L intake w/ Mazda 6 exhaust cams. This combo was HORRIBLE on my turbo up top, but an N/A motor may be a different story. The theory was that the Mazda 6 exhaust cams (which use the smaller pitch, and would install right to an '01/'02 Cougar or 3L) are tuned for the VVT intake cams on the 6, giving more duration for better scavenging. I have a set (somewhere) with very few miles on them if you're interested- I yanked them out of my turbo in favor of standard SVT cams when the dyno plots kept dying at 6k.
j-keezy
08-12-2007, 03:09 AM
do you realy think they would go good on a n/a 2.5
No idea, honestly. If you want to give them a shot, PM me- I'll see if I can find them.
wadespencer99
08-13-2007, 12:15 AM
If Dan can't find his set, I have a nice clean set from an '03 Escape engine.
The Mazda 6 exhaust cams are what I was referring to... I have a set of 3L intake cams to go with it as well. Just have to find them. No PM yet...
SpookSVT
08-13-2007, 08:49 PM
The Mazda 6 exhaust cams are what I was referring to... I have a set of 3L intake cams to go with it as well. Just have to find them. No PM yet...
The Mazda 6 exhaust failed, most likely because it uses a DAMB valvetrain vs. our RFF. Therefore, the specs mean little without the rocker ratio factored in...
You might not switch to 3L cams because the port timing is different vs. the two port types. It's hard to tell if it would hurt power or not unless you try them out first. Something to consider...
Spook-
The cams were visually identical in appearance. I measured cam lobe height and had pictures of the two exhaust cams close-up and with my micrometer measuring lobe height. The engine ran quite satisfactorily with the RFFs and HLAs of our non-VVT Duratecs. For whatever reason, the torque profile died off suddenly around 5.5k RPMs under boost. Torque before that was quite impressive, however. The recommendation came from DemonSVT after results he got in one of his engine/valve timing emulators.
j-keezy
08-14-2007, 12:35 AM
Whats Rff And Mal Or What Ever
LinkMan
08-14-2007, 09:38 AM
RFF == Roller Finger Follower
DAMB == Direct-Acting Mechanical Bucket
HLA == Hydraulic Lash Adjuster
VVT == Variable Valve Timing
Did I miss any? :)
SpookSVT
08-14-2007, 06:43 PM
Interesting...
I wonder what could've caused that to happen under boost...
The plot:
http://dglicoes.home.comcast.net/Run4Sized.jpg
The torque curve was done by 5k.
SpookSVT
08-15-2007, 06:14 PM
Did you run/dyno the car N/A to see if the same issue was present?
No, sorry- This was done after the build was done and ADC kit put in.
SpookSVT
08-16-2007, 10:10 PM
After some reading, the rocker ratio doesn't affect duration. It instead is used to increase lift and enable the use of less aggressive ramp profiles to remove stress from the valvetrain.
The lift could be too great causing excessive turbulence or there isn't enough duration, timing points are sub-optimal? I have no idea really, I'm not too familiar with cam theory yet. That is really odd it just dies like that. :confused:
Do you have the cam timing for those cams?
SpookSVT
08-22-2007, 10:21 PM
DanG: Do you have a spare engine that you could measure the M6 exhaust timing at .050" lift? Also, max lift...