ls2 facotry fuel system limitations
Thread Starter
Racer
Joined: Apr 2012
Posts: 463
Likes: 5
From: Salisbury PA.
ls2 facotry fuel system limitations
doing a build consisting of, intake, ported OEM TB, fast 102 intake, a 7/8" catless headers and full exhaust, trick flow 225cc head and cam combo. this is on my 05 c6, will my factory fuel system handle this? I am going with the FAST fuel rails when I order my intake manifold, but I don't think rails really matter, just doing it for some under the hood eye candy lol.
Melting Slicks
Joined: Oct 2009
Posts: 2,259
Likes: 1
From: Las Vegas NV
St. Jude Donor '10
Stock 42lb injectors should be good to 500+ rwhp.
I'd be more concerned about using a stock tb on that 102 on a stock cube engine...you're bottle-necking that 102, and I'm hoping it won't disappoint you on the dyno as it has so many others with the same setup.
An acquaintance in my car club has an almost identical setup in an LS3 swapped GTO, just added a 102 intake and gained a whopping 1hp and 3 ft/lbs on stock heads and a stock throttle body w/ 1 7/8 headers and a CAI.
You'll be all set if you plan on bigger heads and more cubes down the road though.
I'd be more concerned about using a stock tb on that 102 on a stock cube engine...you're bottle-necking that 102, and I'm hoping it won't disappoint you on the dyno as it has so many others with the same setup.
An acquaintance in my car club has an almost identical setup in an LS3 swapped GTO, just added a 102 intake and gained a whopping 1hp and 3 ft/lbs on stock heads and a stock throttle body w/ 1 7/8 headers and a CAI.
You'll be all set if you plan on bigger heads and more cubes down the road though.
Burning Brakes
Joined: Jul 2013
Posts: 823
Likes: 7
From: Rosewood Heights IL
Stock 42lb injectors should be good to 500+ rwhp.
I'd be more concerned about using a stock tb on that 102 on a stock cube engine...you're bottle-necking that 102, and I'm hoping it won't disappoint you on the dyno as it has so many others with the same setup.
An acquaintance in my car club has an almost identical setup in an LS3 swapped GTO, just added a 102 intake and gained a whopping 1hp and 3 ft/lbs on stock heads and a stock throttle body w/ 1 7/8 headers and a CAI.
You'll be all set if you plan on bigger heads and more cubes down the road though.
I'd be more concerned about using a stock tb on that 102 on a stock cube engine...you're bottle-necking that 102, and I'm hoping it won't disappoint you on the dyno as it has so many others with the same setup.
An acquaintance in my car club has an almost identical setup in an LS3 swapped GTO, just added a 102 intake and gained a whopping 1hp and 3 ft/lbs on stock heads and a stock throttle body w/ 1 7/8 headers and a CAI.
You'll be all set if you plan on bigger heads and more cubes down the road though.
LS3's have good stock Intakes. A FAST102 doesn't gain much over stock. On an LS2 application above, he will gain 20+ rwhp, even with the stock throttle body.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
Thread Starter
Racer
Joined: Apr 2012
Posts: 463
Likes: 5
From: Salisbury PA.
Stock 42lb injectors should be good to 500+ rwhp.
I'd be more concerned about using a stock tb on that 102 on a stock cube engine...you're bottle-necking that 102, and I'm hoping it won't disappoint you on the dyno as it has so many others with the same setup.
An acquaintance in my car club has an almost identical setup in an LS3 swapped GTO, just added a 102 intake and gained a whopping 1hp and 3 ft/lbs on stock heads and a stock throttle body w/ 1 7/8 headers and a CAI.
You'll be all set if you plan on bigger heads and more cubes down the road though.
I'd be more concerned about using a stock tb on that 102 on a stock cube engine...you're bottle-necking that 102, and I'm hoping it won't disappoint you on the dyno as it has so many others with the same setup.
An acquaintance in my car club has an almost identical setup in an LS3 swapped GTO, just added a 102 intake and gained a whopping 1hp and 3 ft/lbs on stock heads and a stock throttle body w/ 1 7/8 headers and a CAI.
You'll be all set if you plan on bigger heads and more cubes down the road though.
Burning Brakes
Joined: Jul 2013
Posts: 823
Likes: 7
From: Rosewood Heights IL
Thread Starter
Racer
Joined: Apr 2012
Posts: 463
Likes: 5
From: Salisbury PA.
sweet, iv always heard of people using stock ported ones and figured most of the restriction did come from the factory manifold. ill be on the hunt for a factory ported one then. cant wait to get this thing back together now! planned on replacing the TB anyways cause my car was going into limp mode on rare occasion, P2135, service traction system. everyone I talked to said replace the TB before replacing the pedal assembly. before I parked the car for winter I didn't have any problems for a while.
Track Junky
Joined: Jun 2007
Posts: 4,074
Likes: 36
From: Orlando Area
Tech Contributor
Safety Car
Joined: May 2011
Posts: 3,807
Likes: 508
From: Oshawa, Ontario
no bottle neck
Stock 42lb injectors should be good to 500+ rwhp.
I'd be more concerned about using a stock tb on that 102 on a stock cube engine...you're bottle-necking that 102, and I'm hoping it won't disappoint you on the dyno as it has so many others with the same setup.
An acquaintance in my car club has an almost identical setup in an LS3 swapped GTO, just added a 102 intake and gained a whopping 1hp and 3 ft/lbs on stock heads and a stock throttle body w/ 1 7/8 headers and a CAI.
You'll be all set if you plan on bigger heads and more cubes down the road though.
I'd be more concerned about using a stock tb on that 102 on a stock cube engine...you're bottle-necking that 102, and I'm hoping it won't disappoint you on the dyno as it has so many others with the same setup.
An acquaintance in my car club has an almost identical setup in an LS3 swapped GTO, just added a 102 intake and gained a whopping 1hp and 3 ft/lbs on stock heads and a stock throttle body w/ 1 7/8 headers and a CAI.
You'll be all set if you plan on bigger heads and more cubes down the road though.
Last edited by irok; Dec 6, 2013 at 11:54 AM.
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
doing a build consisting of, intake, ported OEM TB, fast 102 intake, a 7/8" catless headers and full exhaust, trick flow 225cc head and cam combo. this is on my 05 c6, will my factory fuel system handle this? I am going with the FAST fuel rails when I order my intake manifold, but I don't think rails really matter, just doing it for some under the hood eye candy lol.
You should have 530 rwhp and I personally would not push it that far with stock injectors.
I also personally would not go with the FAST rails...I have horror stories with them leaking on two friends cars..maybe it was setup error but I am not a fan of any fuel leaks. FAST intake on the other hand is a fantastic mod.
Just another man's opinion.
Thread Starter
Racer
Joined: Apr 2012
Posts: 463
Likes: 5
From: Salisbury PA.
^ good advise, not sure if they were bad from factory or not but ill avoid the rails cause I really don't need them, was just going for some looks really. thanks! BTW im gonna go with FAST 46 injectors, or should I just do their 50's?
Tech Contributor
Joined: Jul 2002
Posts: 14,950
Likes: 264
From: St. Louis, MO
St. Jude Donor '08
But I do I do know its imperative you get the conversion tables or the car won't run worth a darn.
Good luck with your build, you're using the best heads out there.
Race Director
Joined: Mar 2005
Posts: 11,549
Likes: 27
From: Southampton NJ
I disagree with the other posters here. My car is at 478 rwhp H/C combo and my injectors are at 99% duty cycle at WOT.
You should have 530 rwhp and I personally would not push it that far with stock injectors.
I also personally would not go with the FAST rails...I have horror stories with them leaking on two friends cars..maybe it was setup error but I am not a fan of any fuel leaks. FAST intake on the other hand is a fantastic mod.
Just another man's opinion.
You should have 530 rwhp and I personally would not push it that far with stock injectors.
I also personally would not go with the FAST rails...I have horror stories with them leaking on two friends cars..maybe it was setup error but I am not a fan of any fuel leaks. FAST intake on the other hand is a fantastic mod.
Just another man's opinion.
Julio said i was maxed out with cam and bolt/ons and recommended me not to run in the cold air, he said summer i would be fine but needed the injectors resized to run in the cold, now im at 60
Race Director
Joined: Oct 2005
Posts: 14,555
Likes: 1,255
From: Saint Albans, WV
When I was running lower 6lb boost my 42 injectors were more than enough at 535whp. When I increased boost I had 60lb Mototrons installed.