Help with cam choice.
09-21-2012, 08:46 AM
#1
Help with cam choice. So I know some of you might be screaming "damn noob search" but I have and I think my head is going to explode 
. This is my first v8 builder ever, ive built tonsss of subaru/evo motors but nothing of this nature (usualy 4 cyl turbo stuff). my setup seams to be tiny bit diff then most since the car is a good 400+ lbs lighter then most the other v8 cars I see around. Here are some stats and hopefuly you guys can help out a new guy. Thanks fellas in advance!
Car:
87 rx7
2800lbs race weight (driver, fuel, etc)
Rossler term 2 th400
Circle d 4c billet converter (3600-4000 stall)
01 lq4 w/ 317 heads
Ls7 lifters
long tubes 1 - 7/8 bbk
single 3.5' spintech muffler
Comp .650 double springs
arp pro rod bolts
8.8 rear w/ 3.73 gears
Holley hp efi
6800 rpm redline
Factory compression 9.5 to 1
Stock lq4 trucky intake manifold
150 plate wet
. This is my first v8 builder ever, ive built tonsss of subaru/evo motors but nothing of this nature (usualy 4 cyl turbo stuff). my setup seams to be tiny bit diff then most since the car is a good 400+ lbs lighter then most the other v8 cars I see around. Here are some stats and hopefuly you guys can help out a new guy. Thanks fellas in advance!Car:
87 rx7
2800lbs race weight (driver, fuel, etc)
Rossler term 2 th400
Circle d 4c billet converter (3600-4000 stall)
01 lq4 w/ 317 heads
Ls7 lifters
long tubes 1 - 7/8 bbk
single 3.5' spintech muffler
Comp .650 double springs
arp pro rod bolts
8.8 rear w/ 3.73 gears
Holley hp efi
6800 rpm redline
Factory compression 9.5 to 1
Stock lq4 trucky intake manifold
150 plate wet
Last edited by 1320king; 09-24-2012 at 07:30 PM.
09-24-2012, 01:39 PM
#5
With that torque converter range and the thought of nitrous, I suspect most cam companies will recommend a cam with a duration in the mid to 230s @ .050" and an exhaust duration in the low 240s @ .050". I would think 112 LSA with 3 or 4 degrees of advance.
Now for turbos you are likely going to want a different grind altogether. I don't have enough practical real world knowledge with these motors to be that specific for the turbo LS motors, but they will likely want a single pattern or even a slight reverse split duration, less duration and a 114 LSA.
Two different cams for sure. You might be able to just buy the turbo cam now and run it with nitrous as long as it is only a 150 shot. But, I would not buy a nitrous cam and try to run it with turbos. It will be far from optimal.
Now for turbos you are likely going to want a different grind altogether. I don't have enough practical real world knowledge with these motors to be that specific for the turbo LS motors, but they will likely want a single pattern or even a slight reverse split duration, less duration and a 114 LSA.
Two different cams for sure. You might be able to just buy the turbo cam now and run it with nitrous as long as it is only a 150 shot. But, I would not buy a nitrous cam and try to run it with turbos. It will be far from optimal.
09-24-2012, 10:31 PM
#7
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What is your ulitmate goal to spray it or go turbo? Like stated I wouldnt waste the money on a $400 nitrous cam if you are going to go turbo.
If you going to go nitrous and want a off the shelf cam the Magic stick 3 is good or the T rex from thunder racing both good nitrous cams.
If you are going to keep the motor and nitrous cam I would call comp,cam motion, or get ahold of pat g and have one of these guys spec a cam for you set up.
In my stock ls1 camaro I have a cam that is spec and spins to 7500 rpms and is going low 11s in a 3200lb car with stock heads and a nitrous converter.
If you going to go nitrous and want a off the shelf cam the Magic stick 3 is good or the T rex from thunder racing both good nitrous cams.
If you are going to keep the motor and nitrous cam I would call comp,cam motion, or get ahold of pat g and have one of these guys spec a cam for you set up.
In my stock ls1 camaro I have a cam that is spec and spins to 7500 rpms and is going low 11s in a 3200lb car with stock heads and a nitrous converter.
