customblackbird

iTrader: (2)

Have a spare 5.3 I’m building, 2003 with 90k ish on it. Stock 706 heads and truck intake. Trying to leave The stock lifters in the trays, and not pull the heads. 7.4” moly pushrods, stock rockers with a possibly bushing upgrade. I picked up some new LS6 valve springs. I have 3 cams to choose from. I have both front covers with and without cam sensor so the LS9 front sensor pickup isn’t and issue as I have the LS2 timing cam sprocket. The turbo I have is a Ebay GT45 and looking to run it. 14-19psi max. Injectors are bosch 60lb @43psi matched from FIC.

This motor will will be built for a 33 coupe kit car so it will be light. I don’t want to spin this thing higher than 6500 and it will be just a street car. I was thinking the LS9 would help with killing some of the low end power to help with traction being a light *** car. The LQ9 cam is worth 40hp over the stock LM7 cam. All should pull great vacuum and be tame enough for LS6 springs. The LS9 is worth like 100hp over the LM7 but trades low end for top end.

What do do you guys think? I’m not looking to get a custom cam, don’t want to squeeze every ounce of power of this thing just a decent power output, smooth and works well on the street.

so should I leave the LM7, swap in the LQ9 or go for broke with the LS9?

G Atsma

I think the LQ9 will give you the best overall driveability and still give some decent power. The LS9 is more a blower cam, not sure it would be good with a turbo.

customblackbird

iTrader: (2)

i agree, can swap without a tune but it will be tuned anyways. A lot of people use the LS9 cam for turbo even tho it’s a blower cam. The added exhaust chokes the turbo alittle but like I said I’m not looking for max power. Engine will
be turbod more than likely or supercharged if I still got it. But the LS9 would give me a huge mid-top end boost and kill low rpm which would help in a light car and a turbo. Not going to go turbo cam and I have all 3 cams and timing covers so it’s not like the LS9 will cost me more to swap.

edit: my current engine has a custom blower cam and I just went turbo. Hopefully the cam will work well enough.

mOtOrHeAd MiKe

iTrader: (8)

Slam an LS9 in that... or grab a used LS6.

customblackbird

iTrader: (2)

haha. Don’t think I’m purchasing any more cams. I’ve got 5 cams and only 2 Motors. I don’t mind the loss in low end with the LS9 as it’s not going to need alot or low end to get a car weighting 2500lbs to get moving.

truckdoug

iTrader: (25)

i just put an lq9 cam in my buddies 5.3/gt45 swapped 78 zephyr wagon

we went low budget with the stock 4l80e converter.

i was surprised at how well it all worked.

TT427

iTrader: (1)

the big cam test that was done a few years ago the lq9 was like 40hp more than the lm7, and only lost 10lb/ft down low... the ls9 was like 100+ but was down 40 at 2500 and still not quite even at 4500.

http://www.hotrod.com/articles/ls-cam-test-comparison/

I dont know how responsive the gt45 is but i would think its lazy being an older design, and ultimately the limiting factor no matter what cam. I would use the lq or trade the ls9 for an ls2/3/6 if wanting stock

customblackbird

iTrader: (2)

hmmm sounds like exactly what I want to do. I wanted to put a manual behind it but honestly it seems like that’s going to cost me butt load as it would have to be a built unit like a tk0 600 or something as I could easy put out 700hp with the GT45. 4L80e would be super easy and cheaper bolt on deal but then it’s still an auto.

customblackbird

iTrader: (2)

yea I posted those number already. I reread that article at least 15x already. That’s why I thought the LS9 would be a decent choice, $100 New and it made 100hp up top but took a bit off the bottom end which would work well in the light car. The issue is it’s a 2003 5.3 so it’s got the **** rods/Pistons so i don’t want to spin higher than 6000-6500 which is about perfect for the LQ9 and the LS9 wants to rev higher.

The GT45 is based off the old diesel designs so they are big, heavy and spool alittle slow. On the 5.3 I’ve read that they start spooling around 3k and are usually full boost by 3500.

Truck doug when does your buddies start to spool and hit full boost by?

etijsma

i went with the LS9 cam for the exact same reasons.

TT427

iTrader: (1)

Was wondering if anyone has seen the Crane 210/218 in the article ever used in a turbo build? Seems to be about the best compromise of low/top end so far as cam timing. Wonder how it would compare to a Triple 12 that's so popular?

truckdoug

iTrader: (25)

yeah that seems accurate. we have it turned way down like 5-6 psi since its now his daily driver and only has 245's on it

customblackbird

iTrader: (2)

i haven’t but that doesn’t mean people don’t. Most people will buy a custom cam vs and off the shelf as they are close in price. Unless u go with the OE $100 cam, trick flow $287 cam they are all $350+.

customblackbird

iTrader: (2)

Haha that’s awsome. Sounds good too! Dang... now I’m stuck between the 2.

TT427

iTrader: (1)

Ya, I get that I just would like to see how it would do considering its modest timing/lift and overall strength. Crane is like a 400+ cam though new, maybe the Vinci is cheaper? I almost had my hands on one then it got pulled 1 day after messaging the guy. Guy supposedly won it from some dyno day raffle. It only had the dyno time on it. Ended up with an EPS 222/226 on 116

JakeFusion

iTrader: (7)

Some food for thought...

http://www.superchevy.com/how-to/eng...ged-ls-engine/

Made a lot more rwhp and rwtq while producing less backpressure. Stage 2 cam vs. LS9. I would go that route...

89BANDIT

Interesting. I'm liking all these destroked boosted combos lately. I've yet to see a destroked steel 6.0 though. When boost is involved, i'd always go with a proper boost cam.

And BTW, Forget turbo on the 33. You have the Turbo Bird. Put a modern roots style blower (Maggie) on that bad boy. Make it sound like and look like a hot rod! IMO!!

cam

iTrader: (9)

COPO 5.3 are destroked 6.0L. There have been a couple home brew set ups done similar as well. IIRC one of the SAM crew built one

89BANDIT

Thank You,
Yes I know that. Although didnt hit me while typing that ^ lol.

TrickFlowTech

With those springs, intake, and RPM range, our TFS-30602001 cam is a pretty good option. It's a bit more expensive than an LS9 cam at $287, but it's more suitable for a couple reasons.

Ours is 216/220 .560 lift and 114 LS. The valve events or -2 I/O, 38 I/C, 48 E/O and -8 E/C.

The LS9 cam has -18 I/O, 49 I/C, 56 E/O and -6 E/C. events.

Our exhaust closing event won't allow high turbine inlet pressures to backfill the cylinder. This is more of a problem with T4 hot sides in single turbo applications.

The bigger factor is our intake closing is 11 degrees earlier. This is going to give it a ton of low and midrange torque in comparison to the LS9. Also a better match to the truck runner length at the top of the rev range.