403 with twins cam change
403 with twins cam change Thinking about changing the cam in the car to see of i can get a little more power out the set up.
Iron block
403 cu block
APR main stud kit
APR head stud kit
Brian Tooley Lifters
ls2 lifter trays
C5R timing chain
Trick performance cam retainer plate for using LS2 timing chain tensioner
LS9 head gaskets
4.005 bore Wiseco -20 pistons
4.00 stroke Eagle crank and rods, with armor coating.
LS3 heads with hollow stainless intake valves, Inconel exhaust valves
heads were decked for flatness
Stock Ls3 intake
92LB injectors at 3 bar.
Lonnies double intake fuel system with billet fuel rails
APS with LGmotorsports turbos
LG motor sports upgraded turbos
New CHRA (Center Housing Rotating Assembly)
New Inconel 71x Turbine Wheel with new 2009 technology
Billet Compressor Wheel ( ~ 60mm inducer) that flows ~ 70lb/min
New Compressor Cover machined for new Compressor Wheel
70mm Inlet
Cam in the car was spec for a 4.8 motor.
Cam spects are
226/237 115.5+6 605/610
Thinking about switching it out to a speed inc TU1.0 or TU1.5
its a street car 2005 GTO full car. 4000lbs
car is making good power now. Just looking to turn the boost up and find a cam that will work better.
When I got this set up tuned power didn't pick up pass 14lbs.
Tthanks
Iron block
403 cu block
APR main stud kit
APR head stud kit
Brian Tooley Lifters
ls2 lifter trays
C5R timing chain
Trick performance cam retainer plate for using LS2 timing chain tensioner
LS9 head gaskets
4.005 bore Wiseco -20 pistons
4.00 stroke Eagle crank and rods, with armor coating.
LS3 heads with hollow stainless intake valves, Inconel exhaust valves
heads were decked for flatness
Stock Ls3 intake
92LB injectors at 3 bar.
Lonnies double intake fuel system with billet fuel rails
APS with LGmotorsports turbos
LG motor sports upgraded turbos
New CHRA (Center Housing Rotating Assembly)
New Inconel 71x Turbine Wheel with new 2009 technology
Billet Compressor Wheel ( ~ 60mm inducer) that flows ~ 70lb/min
New Compressor Cover machined for new Compressor Wheel
70mm Inlet
Cam in the car was spec for a 4.8 motor.
Cam spects are
226/237 115.5+6 605/610
Thinking about switching it out to a speed inc TU1.0 or TU1.5
its a street car 2005 GTO full car. 4000lbs
car is making good power now. Just looking to turn the boost up and find a cam that will work better.
When I got this set up tuned power didn't pick up pass 14lbs.
Tthanks
Last edited by 1fastxz; Sep 5, 2014 at 10:53 PM.
TECH Regular
Joined: Oct 2012
Posts: 476
Likes: 2
Twin turbo motors usually like camshafts that look alot like a blower cam.. Normally they can handle a bigger split and more overlap due to the additional turbine... but in this case with those APS units... the turbines are a little undersized for the size of the motor. That being said I think I would be 230/239 117+4 on something like this. This spec put 900 to the ground with an APS kit on a Corvette a couple years back.
Was the car tuned on a chassis dyno??
Was the car tuned on a chassis dyno??
Right now the cam in the car has a large split in it. I think I'm getting to much pressure coming out the exhaust.
The car has duel 3in exhaust and straight threw mufflers.
The car has duel 3in exhaust and straight threw mufflers.
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
FormerVendor
Joined: Dec 2001
Posts: 2,444
Likes: 2
From: WWW.SPEEDINC.COM
While I wouldn't say there are huge gains in store with a cam swap, reducing overlap at this point will reduce power.
TECH Regular
Joined: Oct 2012
Posts: 476
Likes: 2
Maybe it would Maybe it wouldnt.... With turbines that small and THAT many cubic inches its hard to not be in an excessive backpressure situtation.
But I can tell you this.... 231/239 118+2 made 940+ to the tires in basically the same combination and was still picking up power above 14 psi where his is not and it had -1 degree of overlap.
Last edited by LilJohn; Sep 10, 2014 at 06:33 PM.
FormerVendor
Joined: Dec 2001
Posts: 2,444
Likes: 2
From: WWW.SPEEDINC.COM
I'm sure it would. His lack of power gain after 14psi is likely not due to the cam.
FormerVendor
Joined: Dec 2001
Posts: 2,444
Likes: 2
From: WWW.SPEEDINC.COM
