turbo cam selection (search is down)
06-03-2007, 09:34 PM
#21
im no expert on this, but i have been doing some research and this is what i have found
mild turbo setup you want about a 6 degree reverse split. bigger isnt always better. duration is more important that lift is.
billy bad *** turbo setup= single pattern cam.
lsa isnt as important as overlap is. there is a formula on how to figure overlap, but i cant find it. maybe someone will chime in on that.
everyone says that the ls6 cam is great, but i want something that is choppy at idle, soooo.... that isnt going to work.
if i am wrong on any of this someone please correct me on it.
i have also noticed that alot of people have different opinions on what works and what dont.
mild turbo setup you want about a 6 degree reverse split. bigger isnt always better. duration is more important that lift is.
billy bad *** turbo setup= single pattern cam.
lsa isnt as important as overlap is. there is a formula on how to figure overlap, but i cant find it. maybe someone will chime in on that.
everyone says that the ls6 cam is great, but i want something that is choppy at idle, soooo.... that isnt going to work.
if i am wrong on any of this someone please correct me on it.
i have also noticed that alot of people have different opinions on what works and what dont.
06-03-2007, 09:41 PM
#22
Add the intake and exhaust durations
Divide the results by 4
Subtract the LSA
Multiply the results by 2
_________________
here is the formula for overlap.
less is more, you want something in the negative i think
Divide the results by 4
Subtract the LSA
Multiply the results by 2
_________________
here is the formula for overlap.
less is more, you want something in the negative i think
06-03-2007, 10:05 PM
#23
Originally Posted by ALL UC2
mild turbo setup you want about a 6 degree reverse split. bigger isnt always better.
Mike
06-03-2007, 10:15 PM
#24
Hey thanks for the info guys I really do appreciate your input and time. I would actually like to make this a turbo cam discussion thread since I do believe that we actually haven't had one on the forums here. Correct me if I'm wrong since I can't use the search anyway lol. Thanks again guys. I'll try to post up tommorrow with my thoughts (whether they are worth anything or not) when I have time. Thanks again
Chris
Chris
06-03-2007, 10:35 PM
#25
Originally Posted by engineermike
I don't think this is proven. There's a guy over on turbomustangs.com that just put a much larger cam in his car (from 226/226 to 24x) and it gained a bunch of power. Also, I'm a firm DISbelieve in the whole reverse-split thing, as you can see from my 224/236 cam.
Mike
Mike
What kind of tranny and rear set-up do you have?
06-04-2007, 01:36 AM
#26
TECH Fanatic
iTrader: (4)
Join Date: Mar 2004
Location: San Antonio
Posts: 1,886
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by JAvenger007
huh?
from your vid i thought your cam had a very nice lope to it too.
from your vid i thought your cam had a very nice lope to it too.
Originally Posted by bhz28
what are the spec of your cam 99Z28LS1?
06-04-2007, 01:47 AM
#28
TECH Addict
iTrader: (2)
Join Date: Jul 2004
Location: Ahwatukee, Az
Posts: 2,333
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by ALL UC2
im no expert on this, but i have been doing some research and this is what i have found
mild turbo setup you want about a 6 degree reverse split. bigger isnt always better. duration is more important that lift is.
billy bad *** turbo setup= single pattern cam.
mild turbo setup you want about a 6 degree reverse split. bigger isnt always better. duration is more important that lift is.
billy bad *** turbo setup= single pattern cam.
06-04-2007, 06:03 AM
#29
Originally Posted by ninetres
How is your spool?
Originally Posted by ninetres
What kind of tranny and rear set-up do you have?
Mike
Last edited by engineermike; 06-04-2007 at 09:06 PM.
06-04-2007, 08:53 PM
#31
TECH Fanatic
iTrader: (25)
Join Date: Mar 2004
Location: Newark, Tx.
Posts: 1,810
Likes: 0
Received 0 Likes
on
0 Posts
guys, we have played with a few different cams, including some reverse split. The cam 99z28ls1 has is pretty mild, especially compared to the epp cam. We change specs depending on the motor. The cam is nothing crazy, but it does work very well on a mild boost 346; better than a reverse split on a similar motor.
06-04-2007, 10:19 PM
#32
keep it coming. shows what i know about this subject. freaking internet, how the hell are you supposed to know what is right and what isnt??????
can someone that is an expert on this stuff give us and explination on what works and what doesnt and WHY????? there has to be someone on here that can give this info
can someone that is an expert on this stuff give us and explination on what works and what doesnt and WHY????? there has to be someone on here that can give this info
06-05-2007, 06:21 AM
#33
Staging Lane
Join Date: Apr 2007
Location: Melbourne, Australia
Posts: 57
Likes: 0
Received 0 Likes
on
0 Posts
I have a 408 Twin Garrett Turbo .
Its an Auto in a 4 door Commodore Sedan , ( daily Driven).
I'm in Australia for those that don't know what a commodore is .
What cam would you guys recomend for my setup ?
Its an Auto in a 4 door Commodore Sedan , ( daily Driven).
I'm in Australia for those that don't know what a commodore is .
What cam would you guys recomend for my setup ?
06-05-2007, 07:55 AM
#34
Originally Posted by ALL UC2
can someone that is an expert on this stuff give us and explination on what works and what doesnt and WHY????? there has to be someone on here that can give this info
The general rules that have worked for me are:
- Choose IVC based on rpm range desired. Rpm range should match that which the turbo can support. For instance, a 408 with a T61 isn't going to make peak power at 7000 rpm regardless of the cam.
- EVC should be IVC + 5 to 10 deg. This will match up the exhaust and intake rpm ranges reasonably well.
- Overlap has not shown to be bad for power in a turbo application. Choose the amount of overlap based on desired idle quality. I have 5 deg of overlap and it works well with a pretty poor backpressure ratio (17 psi boost and 33 psi backpressure). I'm sure there's a limit to this, but I'm not sure anyone has found it with our baby street cams.
Mike
06-05-2007, 10:11 PM
#36
Originally Posted by engineermike
The deal is that very few have done true turbo cam tests and they aren't releasing the results. Cam Motion has not done this testing.
The general rules that have worked for me are:
- Choose IVC based on rpm range desired. Rpm range should match that which the turbo can support. For instance, a 408 with a T61 isn't going to make peak power at 7000 rpm regardless of the cam.
- EVC should be IVC + 5 to 10 deg. This will match up the exhaust and intake rpm ranges reasonably well.
- Overlap has not shown to be bad for power in a turbo application. Choose the amount of overlap based on desired idle quality. I have 5 deg of overlap and it works well with a pretty poor backpressure ratio (17 psi boost and 33 psi backpressure). I'm sure there's a limit to this, but I'm not sure anyone has found it with our baby street cams.
Mike
The general rules that have worked for me are:
- Choose IVC based on rpm range desired. Rpm range should match that which the turbo can support. For instance, a 408 with a T61 isn't going to make peak power at 7000 rpm regardless of the cam.
- EVC should be IVC + 5 to 10 deg. This will match up the exhaust and intake rpm ranges reasonably well.
- Overlap has not shown to be bad for power in a turbo application. Choose the amount of overlap based on desired idle quality. I have 5 deg of overlap and it works well with a pretty poor backpressure ratio (17 psi boost and 33 psi backpressure). I'm sure there's a limit to this, but I'm not sure anyone has found it with our baby street cams.
Mike
how do you figure out how much backpressure that you have???
anyone tried a hotcam with a turbo setup????? i know ls6 cams are popular but never seen a hotcam. im wanting a big thumpy bump idle but dont want something that is going to hurt performance.
06-05-2007, 10:51 PM
#37
11 Second Club
iTrader: (2)
Join Date: Dec 2003
Location: Montgomery, AL.
Posts: 535
Likes: 0
Received 0 Likes
on
0 Posts
Here is some great reading regarding turbo camshafts. http://www.turbochargedpower.com/Camshafts.htm
Jim C.
Jim C.
06-06-2007, 06:00 AM
#38
Originally Posted by ALL UC2
how do you figure out how much backpressure that you have???
Originally Posted by ALL UC2
anyone tried a hotcam with a turbo setup?????
06-11-2007, 08:23 PM
#39
On The Tree
iTrader: (1)
Join Date: Aug 2006
Location: ALABAMA
Posts: 168
Likes: 0
Received 0 Likes
on
0 Posts
Got an up date on the epp cam I was told by my tuner that cam would not work for a turbo car all that well. He told me it would be a dog on the low end and drive bad. Might work for a full race car turbo car with lots of power, but not what I got a weekend warrior. Not trying to hate on epp by no means they might make good products I have no idea. Just sharing with yall what I was told.
Jimmy
Jimmy
