Fosnot

iTrader: (15)

I was looking at doing a top end replacement on my stock displacement LS1; As a background on the car, it has 3.73 gears, a 3800 stall converter, 1 7/8" Pacesetter LT's w/ no cats/egr/air that empty out to 3 inch duels that dump before the axle.

That being said, I was looking at getting a set of 5.3L heads (casting 706), a Patriot cam wit the following specs: Intake Duration: 225 @.050", Exhaust, Duration: 229 @.050", Intake Lift: .580", Exhaust Lift: .590",LSA: 114+4;


Semi related to this, would an LS6 intake (unported, stock TB/MAF) be too restrictive for that sized cam? Or would an old FAST 90/90 or 102mm intake be needed?

Finally with either of those two setups what would be the needed fuel system upgrade to handle that much air? Injector sizes, rail upgrades, pump size, etc?

bayer-z28

iTrader: (14)

The LS6 intake will be fine for that cam, depending on your budget. The cam isn't that radical, so you CAN run a fast intake on it for a couple extra HP gain (over the LS6, maybe 15hp gain.)

The FAST 90's are hard to come by now and the 102 is a basically an upgraded design, but requires a couple other items to get it to work. The 90's are available through retail if you know where to look.

I ran an LS6 intake on mine for a couple years before doing the 102 swap last winter.

01ssreda4

iTrader: (96)

I would put a Ractronix 255 and hotwire kit in it and run some 36-42 pound injectors. And before anyone pipes up that a 42 pounder is too big, I run them on my cam only car with zero issues. I'm running the FIC rejetted stockers.

Fosnot

iTrader: (15)

How much 'wiggle room' would I have w/ the stock pump and injectors w/ an LS6?
If there is none with the 28#'ers, how much capacity would the factory pump have with the same setup at 36# or 42#?

01ssreda4

iTrader: (96)

I'm currently on my stock pump and 42s, cam and bolts on and the injectors are at 65% duty cycle at 6500 rpms. So I have room to grow. I don't however think that the fuel pump would agree. I have a Racetronix kit waiting to go in to solve that issue. I should be able to feed another 100hp at the wheel without issue. Rule of thumb is to keep your duty cycle on your injectors at 80% or lower.

bayer-z28

iTrader: (14)

^ I was at H/C/FIC 42's, FAST 102 and my tuner said I was leaning out at higher R's with my FIC 42's. We ordered the RT 255 with the hotwire kit and that seemed to satisfy it. But low and behold my fuel pressure is way down and I'm in the middle of figuring that out now. I'm hoping it's a filter. -Pressure dies off at higher R's.

ZL1Killa

iTrader: (17)

DAMN RIGHT. +1 for what you need to do.

and 42# injectors, whether lucas/delphi or other brand are a breeze to tune on even a stock car.