Cam selection
Thread Starter
Racer
Joined: May 2010
Posts: 448
Likes: 3
From: Olathe KS
Cam selection
I am on the hunt for a new cam.
Here is my car:
1973 corvette
1989 350 bored .030
Edelbrock torquer II manifold(going to be replaced with an edelbrock rpm air gap)
World S/R torquer iron heads
Edelbrock 600cfm carb
TH400 with shift kit and stock stall (will be getting a 2500 stall)
3.08 gears
Mechanical fuel pump and HEI
Goal is to be street able, but get under the 13 1/4 mile mark, or close.
Any recommendations?
Here is my car:
1973 corvette
1989 350 bored .030
Edelbrock torquer II manifold(going to be replaced with an edelbrock rpm air gap)
World S/R torquer iron heads
Edelbrock 600cfm carb
TH400 with shift kit and stock stall (will be getting a 2500 stall)
3.08 gears
Mechanical fuel pump and HEI
Goal is to be street able, but get under the 13 1/4 mile mark, or close.
Any recommendations?
Last edited by Killingsworth 73; Jun 18, 2014 at 10:14 PM.
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
I am on the hunt for a new cam.
Here is my car:
1973 corvette
1989 350 bored .030
Edelbrock torquer II manifold(going to be replaced with an edelbrock rpm air gap)
World S/R torquer iron heads
TH400 with shift kit and stock stall (will be getting a 2500 stall)
3.08 gears
Mechanical fuel pump and HEI
Goal is to be street able, but get under the 13 1/4 mile mark, or close.
Any recommendations?
Here is my car:
1973 corvette
1989 350 bored .030
Edelbrock torquer II manifold(going to be replaced with an edelbrock rpm air gap)
World S/R torquer iron heads
TH400 with shift kit and stock stall (will be getting a 2500 stall)
3.08 gears
Mechanical fuel pump and HEI
Goal is to be street able, but get under the 13 1/4 mile mark, or close.
Any recommendations?
1970 LT1 370 HP with 4 speed ran 14.2 in the 1/4 Mile with 11 to 1 comp, high rise intake, Holley 780 and a solid lifter cam capable of 7000 RPM shifts.
http://www.car-times.com/DoShowMoreC...il.php?vid=409
To cut 1.2 seconds off that you will need another 100 HP over the LT1, deep rear gears, drag radials and a dialed in car.
1968 Corvette 427 L88 12.5 to 1 Solid lifters, 13.50 sec @ 111 MPH
1969 Corvette 427 L88 12.5 to 1 solid lifters, 13.56 sec @ 111.1 MPH
You will never come anywhere close to 13's with 3.08 gears.
If you want a cam recommendation to get the most out of what you got that can be done but just trying to temper your expectations.
Need Head CC, piston CC, Deck to piston height and head gasket used to figure compression to start. Exhaust specs? Headers? 2 1/2" true duals? low restriction mufflers?
Last edited by 63mako; Jun 18, 2014 at 10:45 PM.
Thread Starter
Racer
Joined: May 2010
Posts: 448
Likes: 3
From: Olathe KS
You do know S/R stands for stock replacement right?
1970 LT1 370 HP with 4 speed ran 14.2 in the 1/4 Mile with 11 to 1 comp, high rise intake, Holley 780 and a solid lifter cam capable of 7000 RPM shifts.
http://www.car-times.com/DoShowMoreC...il.php?vid=409
To cut 1.2 seconds off that you will need another 100 HP over the LT1, deep rear gears, drag radials and a dialed in car.
1968 Corvette 427 L88 12.5 to 1 Solid lifters, 13.50 sec @ 111 MPH
1969 Corvette 427 L88 12.5 to 1 solid lifters, 13.56 sec @ 111.1 MPH
You will never come anywhere close to 13's with 3.08 gears.
If you want a cam recommendation to get the most out of what you got that can be done but just trying to temper your expectations.
Need Head CC, piston CC, Deck to piston height and head gasket used to figure compression to start. Exhaust specs? Headers? 2 1/2" true duals? low restriction mufflers?
1970 LT1 370 HP with 4 speed ran 14.2 in the 1/4 Mile with 11 to 1 comp, high rise intake, Holley 780 and a solid lifter cam capable of 7000 RPM shifts.
http://www.car-times.com/DoShowMoreC...il.php?vid=409
To cut 1.2 seconds off that you will need another 100 HP over the LT1, deep rear gears, drag radials and a dialed in car.
1968 Corvette 427 L88 12.5 to 1 Solid lifters, 13.50 sec @ 111 MPH
1969 Corvette 427 L88 12.5 to 1 solid lifters, 13.56 sec @ 111.1 MPH
You will never come anywhere close to 13's with 3.08 gears.
If you want a cam recommendation to get the most out of what you got that can be done but just trying to temper your expectations.
Need Head CC, piston CC, Deck to piston height and head gasket used to figure compression to start. Exhaust specs? Headers? 2 1/2" true duals? low restriction mufflers?
Burning Brakes
Joined: Sep 2012
Posts: 818
Likes: 0
From: coon rapids mn
carefully figure out your static compression ,depending on the cc of the heads you get.pick the right cam to get a street friendly dynamic compression.making torque and some suspension parts should meet your goals.you will need long slot rockers with the correct push rod length .you can find good heads for under $1000 if you shop around .I have seen good prices at speed way ,and competition products .other will chime in on where to find good heads for a good price .
Melting Slicks
Joined: Oct 2011
Posts: 2,748
Likes: 90
From: Sacramento California
C2 of Year Finalist (performance mods) 2019
2018 C2 of Year Finalist
Good Luck. Heads and a Roller cam will get you close but without the Compression ratio it would be a wild guess. And 3.08s will never get you there without a tractor motor. (500 ft/bs torque)
my old 67 Camaro with a .30 over 350, Dart Heads, TH400 big cam and 4.10 gears would barely run 13.2.
my old 67 Camaro with a .30 over 350, Dart Heads, TH400 big cam and 4.10 gears would barely run 13.2.
Last edited by DucatiDon; Jun 19, 2014 at 12:31 AM.
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
You really need to nail down your compression ratio to select the cam. Since your changing the cam I would take it down to the short block, get some accurate measurements and come back to this thread. New heads, the right roller cam and 2 1/2" exhaust will get you all you can get out of what you have but need accurate info to make a recommendation.
Last edited by 63mako; Jun 19, 2014 at 02:11 AM.
Burning Brakes
Joined: May 2006
Posts: 774
Likes: 1
From: Round Rock Texas
I am on the hunt for a new cam.
Here is my car:
1973 corvette
1989 350 bored .030
Edelbrock torquer II manifold(going to be replaced with an edelbrock rpm air gap)
World S/R torquer iron heads
Edelbrock 600cfm carb
TH400 with shift kit and stock stall (will be getting a 2500 stall)
3.08 gears
Mechanical fuel pump and HEI
Goal is to be street able, but get under the 13 1/4 mile mark, or close.
Any recommendations?
Here is my car:
1973 corvette
1989 350 bored .030
Edelbrock torquer II manifold(going to be replaced with an edelbrock rpm air gap)
World S/R torquer iron heads
Edelbrock 600cfm carb
TH400 with shift kit and stock stall (will be getting a 2500 stall)
3.08 gears
Mechanical fuel pump and HEI
Goal is to be street able, but get under the 13 1/4 mile mark, or close.
Any recommendations?
Good luck.
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Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
You really need to nail down your compression ratio to select the cam. Since your changing the cam I would take it down to the short block, get some accurate measurements and come back to this thread. New heads, the right roller cam and 2 1/2" exhaust will get you all you can get out of what you have but need accurate info to make a recommendation.
Racer
Joined: Mar 2009
Posts: 276
Likes: 31
From: Brant County Ontario
If your staying with the heads and exhaust still need the accurate compression info. It has been rebuilt. Could be anywhere between 8.2 to 1 to 10 to 1. Cam selection would be drastically different. A cam that is perfect @ 8.2 to 1 could detonate your pistons out of the hole @ 10 to 1. A cam perfect for 10 to 1 could lose noticeable power over what you have @ 8.2 to 1.
Le Mans Master
Joined: May 2002
Posts: 5,084
Likes: 786
From: Lebanon Township New Jersey
No need to pull a piston out, but you will need to remove a head, determine the combustion chamber volume, and the piston depth in the hole. (This is why I suggested you start a new thread for cam selection).
Thread Starter
Racer
Joined: May 2010
Posts: 448
Likes: 3
From: Olathe KS
OK. I need to pull the drivers side head anyways (bad head gasket). Is there a thread how to actually do this? Which measurements I need to take and how?
these cam threads always interest me 
Le Mans Master
Joined: May 2007
Posts: 5,009
Likes: 1,116
From: North tonawanda NY
some cams have more overlap than others and some bleed off compression while some build it (so I've read) I changed my cam choice three times as I learned this stuff and found the jeep strokers calculator (sorry I dont have the link) was a very usful tool in determining my static and dynamic compression ratios with my components and measured deck height and such.... I went with the cam I did because even though my static compression is high for iron heads my dynamic compression was very doable with my quench area... (Mako was the first to educate me on quench a couple years ago actually.... anyway 2 years later and the engine is finally in and just waiting my tweaking of the drivers side, sidepipe header to clear the steering and fluids and I'll be firing my new build up this sunday 
I knew almost nothing about sbc or rebuilding an engine when I started my quest a couple years ago.... lots of your tube videos and reading....
I knew almost nothing about sbc or rebuilding an engine when I started my quest a couple years ago.... lots of your tube videos and reading....
Le Mans Master
Joined: May 2002
Posts: 5,084
Likes: 786
From: Lebanon Township New Jersey
You said earlier that when you remove a head you will find some markings indicating chamber volume - that's the hard part. For the piston depth, its measured with the piston at TDC, using a dial indicator mounted on a bracket to measure the difference between the deck surface and the top of the piston.
Le Mans Master
Joined: May 2007
Posts: 5,009
Likes: 1,116
From: North tonawanda NY
You said earlier that when you remove a head you will find some markings indicating chamber volume - that's the hard part. For the piston depth, its measured with the piston at TDC, using a dial indicator mounted on a bracket to measure the difference between the deck surface and the top of the piston.