twilightprotege
Member
- :
- 2001 323 Astina SP20 (P5)
the adj cam gears have timing marks (2 degrees). you can best guess what will work, but 2 degrees of movement wont give the butt dyno a noticeable difference, but on a dyno it will
ATTN: Cam owners
- Thread starter zmepro
- Start date
Twilight or akhilleus,
when you got cams, or had someone adjust them, did you happen to check the point where the valves start to open (IVO,EVO,IVC,EVC)? To be really accurate with gear advancing or retarding you should know where the cams actually started.
I guess you could find out if you turned the crank with the valve cover off and a degree chart (otherwise known as a circle) on the cam....
when you got cams, or had someone adjust them, did you happen to check the point where the valves start to open (IVO,EVO,IVC,EVC)? To be really accurate with gear advancing or retarding you should know where the cams actually started.
I guess you could find out if you turned the crank with the valve cover off and a degree chart (otherwise known as a circle) on the cam....
twilightprotege
Member
- :
- 2001 323 Astina SP20 (P5)
zme - between a bad tuned cam gear and a good one you could easily see a difference of 20whp...probably even more
iluvmacs - i originally got a print out when had my custom cams ground. has all that kinda stuff....but unfortunately these figures are with 0.012" of clearance between the cam and shim (i have 0.009")
@ 0.050"valve lift
ivo 0.9 bdc
ivc 37.9 abc
exo 41.0 bbc
exc 1.9 btc
i'll be taking this sheet along with me when i get my cam gears tuned into the exhaust
iluvmacs - i originally got a print out when had my custom cams ground. has all that kinda stuff....but unfortunately these figures are with 0.012" of clearance between the cam and shim (i have 0.009")
@ 0.050"valve lift
ivo 0.9 bdc
ivc 37.9 abc
exo 41.0 bbc
exc 1.9 btc
i'll be taking this sheet along with me when i get my cam gears tuned into the exhaust
Twilight, thats for the new cam, not the stock ones right? If you want I can run your cams through Desktop Dyno, but to be accurate I need to compare them to the stock cams, which I don't have degrees for.
Akhilleus, did they tell you the difference (how much they advanced/retarded your cams), and did they tell you what the initial or final numbers were? If you know what they are please PM, email, or post.
Thanks
Akhilleus, did they tell you the difference (how much they advanced/retarded your cams), and did they tell you what the initial or final numbers were? If you know what they are please PM, email, or post.
Thanks
twilightprotege
Member
- :
- 2001 323 Astina SP20 (P5)
yeah they are my custom cam specs. run them through desktop dyno if that's ok and email me or pm me with any other info you need on my engine etc. am interested in seeing what it says! dont forget i have 9.7:1 compression ratio not 9.1
twilightprotege
Member
- :
- 2001 323 Astina SP20 (P5)
yep, i just went and got my old cam gear. each tooth represents 8.5714286.....degrees
there are 42 teeth on the cam gear
there are 42 teeth on the cam gear
twilightprotege
Member
- :
- 2001 323 Astina SP20 (P5)
oh hang on....the cams are traveling half the speed of the crank...could be half that figure (uhm) ... depends on how they calculate the degrees on the cam gear though...
twilightprotege
Member
- :
- 2001 323 Astina SP20 (P5)
yes.
what i did when i got my cam gears was adjust them, go for a drive and see how it feels, come home and adjust them again etc. at the moment i've got them adjusted so that i get pretty good fuel economy considering how big my cams are. i'm certain they arent making maximum power though...
a more certain way of off dyno tuning is to adjust them, go to a spot and time how long it takes to go over a certain distance in a constant gear. which ever setting gives you the shortest time, that's your best setting...the problem with this is the conditions change and you might get better times with a setting that actually isnt better
but still...spend the money on some dyno time. that way you know for sure you're getting the best power you can
what i did when i got my cam gears was adjust them, go for a drive and see how it feels, come home and adjust them again etc. at the moment i've got them adjusted so that i get pretty good fuel economy considering how big my cams are. i'm certain they arent making maximum power though...
a more certain way of off dyno tuning is to adjust them, go to a spot and time how long it takes to go over a certain distance in a constant gear. which ever setting gives you the shortest time, that's your best setting...the problem with this is the conditions change and you might get better times with a setting that actually isnt better
but still...spend the money on some dyno time. that way you know for sure you're getting the best power you can
Turbo Matty P
Banned
also, I think what twillight means to say is:
Don't judge your "power" based on a peak number. Look for what will provide the most area under the curve. THAT is what makes power and pull.
Don't judge your "power" based on a peak number. Look for what will provide the most area under the curve. THAT is what makes power and pull.
twilightprotege
Member
- :
- 2001 323 Astina SP20 (P5)
yeah that too.
when i take my car in to get the cam gears tuned (ie after the exhaust is installed), i'm going to ask the dyno place to give me two cam gear settings.
1 for maximum area under the torque curve from 0-4500rpm, and for maximum area under the horsepower curve from 4500-redline.
that way i'll use the torque setting for every day driving, then the other for spirited drives at night and racing.....i wouldnt be surprised either if they were the same setting on the cam gear too!
when i take my car in to get the cam gears tuned (ie after the exhaust is installed), i'm going to ask the dyno place to give me two cam gear settings.
1 for maximum area under the torque curve from 0-4500rpm, and for maximum area under the horsepower curve from 4500-redline.
that way i'll use the torque setting for every day driving, then the other for spirited drives at night and racing.....i wouldnt be surprised either if they were the same setting on the cam gear too!
FunkyBuddha
Tuned by Slick Nick
- :
- 2003 Spicy Orange MSP
Well I got both cams. Jspec and Mazdaspeed. I say..go for it. Nice gain upwards of 3500 rpm through all gears. The car's better on the highway now too.
desktop dyno files
Here are the dyno charts the computer gets with stock setup (as close as i can get), and what's published about twilights setup. T- I dont' think I have your exact specs. PM or email and I'll get you a more accurate dyno estimate.
You'll notice that peak hp is still at 6000 rpm, but about 143hp. That falls only to 142 at redline (6500 rpm).
Here are the dyno charts the computer gets with stock setup (as close as i can get), and what's published about twilights setup. T- I dont' think I have your exact specs. PM or email and I'll get you a more accurate dyno estimate.
You'll notice that peak hp is still at 6000 rpm, but about 143hp. That falls only to 142 at redline (6500 rpm).
Attachments
twilightprotege
Member
- :
- 2001 323 Astina SP20 (P5)
yeah those graphs arent too far away from what you'd expect at all...
macs - you have pm
macs - you have pm
