cam for 388 all bore
02-07-2004, 05:02 PM
#1
cam for 388 all bore what would be a good hydraulic cam for this car.....
Z28
daily driver/road race (not drag race)
~3300lbs
3.73 gear
M6 with aluminum flywheel
engine:
Darton wet sleeved LS1 block
4.130" forged pistons (BIG valve releafs) @ 11.0:1 CR
6.300" rod
stock crank
stage 3 heads (2.08/1.60 valves)
support:
Hooker Lts (1 3/4 primarties)
2.5" x-pipe true dual exhaust with bullets
46lb injectors
LS6 intake
don't really want to spin to 7K (would like a shift somewhere between 6500 and 6800), needs to be able to idle at 1K RPM AT MOST! (LS1Edit), make the best possible HP, and should have a really hard/rough idle (I want a MUSCLE CAR).....
Z28
daily driver/road race (not drag race)
~3300lbs
3.73 gear
M6 with aluminum flywheel
engine:
Darton wet sleeved LS1 block
4.130" forged pistons (BIG valve releafs) @ 11.0:1 CR
6.300" rod
stock crank
stage 3 heads (2.08/1.60 valves)
support:
Hooker Lts (1 3/4 primarties)
2.5" x-pipe true dual exhaust with bullets
46lb injectors
LS6 intake
don't really want to spin to 7K (would like a shift somewhere between 6500 and 6800), needs to be able to idle at 1K RPM AT MOST! (LS1Edit), make the best possible HP, and should have a really hard/rough idle (I want a MUSCLE CAR).....
02-07-2004, 06:49 PM
#3
TECH Resident
iTrader: (1)
Join Date: Nov 2001
Location: Huntington Beach, Ca
Posts: 813
Likes: 0
Received 0 Likes
on
0 Posts
It you want to shift around 6800 I wouldn't go with an LSA of less than 114. Bigger cubes really bring down the power band, with 388 peaked at 6250 with a 230/236 114 cam and made power all the way to 7k. If you were to get a 112 I think it would be even lower. Mine was perfect for a daily driver and had and very nice lope to it. You'd probably be best off with a 238-240 duration intake/exhaust, 114 LSA, and Im assuming your peak flow numbers at @ .600 so you'd want the lift to around there. A couple of questions and comments on your setup though: How come you went with such a long rod? Also if you want max power out of your setup I'd definitely look into getting bigger headers (1 7/8"), as a preferrance I'd also go back a to 3" inch y-pipe with dual cutouts, it'd make more power and be lighter than a true dual exhaust; also unless your going to spray the motor I think 46# injectors are overkill x2, I had SVO 30# my 388 and they were plenty. Good luck.
02-07-2004, 06:57 PM
#4
I said 6800RPM as a MAX RPM I want to spin to....the lower the better (engine life)......
my peak flow numbers were ~ .600 lift but I am SETTING THE MAX lift AT 0.595" (for valve spring life)....
The exhaust stays AS IS. I'm not going to change the headers (too much money for what I would get), I love the sound of the true duals (I have had 4 cat backs and they all sounded like SH*T!!! compared to this setup), and I need the 2.5" pipe for ground clearance. So the cam needs to take all of this into account.
The injectors are probubly WAY larger than I "need" but I already have them.
my peak flow numbers were ~ .600 lift but I am SETTING THE MAX lift AT 0.595" (for valve spring life)....
The exhaust stays AS IS. I'm not going to change the headers (too much money for what I would get), I love the sound of the true duals (I have had 4 cat backs and they all sounded like SH*T!!! compared to this setup), and I need the 2.5" pipe for ground clearance. So the cam needs to take all of this into account.
The injectors are probubly WAY larger than I "need" but I already have them.
02-07-2004, 07:36 PM
#6
Originally Posted by Ragtop 99
He's willing to take a rough, "muscle car" idle at 900 - 950 rpm. That should allow for a lower LSA than 114 and for decent split to overcome his small Y-pipe.
now we are getting the idea
I was thinking 112 at the most on the LSA (was actually tossing a 110 or 108 around). The question is how much duration can I run and not have a compleat dog down low (don't want the car to be a lead weight till 4000RPM). Then how much extra exhaust should I have to make up for the "restriction" of the exhaust system?
02-07-2004, 11:46 PM
#7
TECH Junkie
Join Date: Jan 2002
Location: At the office
Posts: 3,015
Likes: 0
Received 0 Likes
on
0 Posts
Chris, I'd focus on valve events and try to get an earlier intake valve closing to keep the cylinder pressures and dynamic compression up at lower rpm. Like everyone is suggesting, less intake duration and keep it on a tigher LSA.
The LSA will obviously only shift the powerband so much....the difference between the powerbands from a 110 to a 114 LSA on the same duration/lift cam is going to be only 400rpm....I'd also talk to LG Motorsports about their G5X-5 and up cams and see how they perform...they seem to do a good job of getting good low and top end, and good idle out of their big cams, which don't peak to high.
I personally would like to see you try something like a 240ish/250ish .615ish/.605ish on say a 111-112 LSA.
The LSA will obviously only shift the powerband so much....the difference between the powerbands from a 110 to a 114 LSA on the same duration/lift cam is going to be only 400rpm....I'd also talk to LG Motorsports about their G5X-5 and up cams and see how they perform...they seem to do a good job of getting good low and top end, and good idle out of their big cams, which don't peak to high.
I personally would like to see you try something like a 240ish/250ish .615ish/.605ish on say a 111-112 LSA.
Trending Topics
02-07-2004, 11:53 PM
#8
TECH Fanatic
iTrader: (1)
Join Date: Oct 2002
Location: Elmhurst, IL (Chicago Suburb)
Posts: 1,851
Likes: 0
Received 0 Likes
on
0 Posts
I say go with the battled tested and proven MTI S1 cam i'm running in my 427 with specs of 244/244, .612 lift on a 112lsa. Could be the perfect cam for you as this cam rocks for both the street and strip on bigger cubed applications!
02-08-2004, 02:19 PM
#9
what about:
242/246, 0.590/0.590, 110LSA
244/248, 0.590/0.590, 110LSA
The GrandAM cam is a 239/251, 0.570/0.570, 106LSA.....why so much exhaust and so little LSA?
Then the G5X_ cams are running something like 6-8 degrees more exhaust than intake. At what point do you reach "too much exhaust"?
242/246, 0.590/0.590, 110LSA
244/248, 0.590/0.590, 110LSA
The GrandAM cam is a 239/251, 0.570/0.570, 106LSA.....why so much exhaust and so little LSA?
Then the G5X_ cams are running something like 6-8 degrees more exhaust than intake. At what point do you reach "too much exhaust"?
Last edited by 2001CamaroGuy; 02-08-2004 at 02:24 PM.
02-08-2004, 03:40 PM
#10
TECH Resident
iTrader: (1)
Join Date: Nov 2001
Location: Huntington Beach, Ca
Posts: 813
Likes: 0
Received 0 Likes
on
0 Posts
Ok, I think you're at the point of wanting your cake and eating it too. Those cams you mentioned above would suck *** for daily driving. I love people that want gobbs of power up top and down low and don't want to sacrifice any driveability, yeah in a perfect world that'd be great and all.I wouldn't go any lower with than a 112 LSA, why are you afraid of spinning for motor 6800 rpms? If it's forged you really have nothing to worry about, and last time I checked true duals were much worse for ground clearance
02-08-2004, 03:50 PM
#11
Originally Posted by Linear Velocity
Ok, I think you're at the point of wanting your cake and eating it too. Those cams you mentioned above would suck *** for daily driving. I love people that want gobbs of power up top and down low and don't want to sacrifice any driveability, yeah in a perfect world that'd be great and all.I wouldn't go any lower with than a 112 LSA, why are you afraid of spinning for motor 6800 rpms? If it's forged you really have nothing to worry about, and last time I checked true duals were much worse for ground clearance
I don't want to spin it up really high because of valvetrain and cylinder wall life (would like to make this motor last 75K-100K miles). True duals do suck for ground clearance but there is no need to make it WORSE by going UP TO 3" (thus why I need it to work with WHAT I HAVE).
Last edited by 2001CamaroGuy; 02-08-2004 at 04:00 PM.
02-08-2004, 03:55 PM
#13
Originally Posted by Stu'sWS6
Just sell the injectors you have, 46lb @ what fuel psi? What brand injectors are they? I say delphi 37's or fms 30lb inj. Who ported the heads?
The heads were ported by a local engine builder and I am very happy with them. With a stock bore (3.898" bore) and an LS1 intake (NOT LS6), he got about 295CFM on the intake at 0.550"lift.
Last edited by 2001CamaroGuy; 02-08-2004 at 04:06 PM.
02-08-2004, 05:12 PM
#14
TECH Addict
iTrader: (1)
Join Date: Nov 2001
Location: Michigan
Posts: 2,161
Likes: 0
Received 0 Likes
on
0 Posts
I've had "good luck" with the 232/236 112 ls that I am running. I will probably end up going bigger, but this one has produced good results for a what most would consider a small cam for this 393 All Bore.
It does not stall at the stop lights. That's what I like about it. It ran a 11.1 @ 123, with a crappy 60'.
The car is not a dyno queen, with the 400TH, HD driveshaft, 12 bolt, & slicks, but showed 420. Def would have been in the 450 + range with the stock drivetrain.
I would guess that you would be good up to a 240 240, if you had a good tuner who could get the idle right.
It does not stall at the stop lights. That's what I like about it. It ran a 11.1 @ 123, with a crappy 60'.
The car is not a dyno queen, with the 400TH, HD driveshaft, 12 bolt, & slicks, but showed 420. Def would have been in the 450 + range with the stock drivetrain.
I would guess that you would be good up to a 240 240, if you had a good tuner who could get the idle right.
02-08-2004, 07:55 PM
#15
I was wondering if a cam in the range of 238/246 on a 110 or 112 would do the trick. 2 - 4 degrees advance on the 112 might help bring the power band down a bit. A 242/250 would be manly too
What's the deal on ground clearance? Is your car lowered? I have a 3" Y-Pipe feeding into a 3.5" I-pipe and I have no issues and my neighborhood has speed humps.
What's the deal on ground clearance? Is your car lowered? I have a 3" Y-Pipe feeding into a 3.5" I-pipe and I have no issues and my neighborhood has speed humps.
02-08-2004, 08:10 PM
#16
lowered big time......I can get over the "average" speed bump if I go 1-2 MPH but every once in a while I find those "speed bumps from hell" (look like small mountain ranges in the road) and I go "OHHH CRAP!!! This is going to be bad......."
I didn't think to mention it, but there is a guy here with an ASA cam in a stock head 346 and I could deal with that as a daily driver (I LOVE how this guys car sounds at idle ). I have looked at the GrandAm cam but that 251 exhaust duration and the 106LSA just seems to much to get me anything. I'm looking for something in between.
I didn't think to mention it, but there is a guy here with an ASA cam in a stock head 346 and I could deal with that as a daily driver (I LOVE how this guys car sounds at idle
). I have looked at the GrandAm cam but that 251 exhaust duration and the 106LSA just seems to much to get me anything. I'm looking for something in between. 
