RyanSws6

iTrader: (72)

Looking to swap my top end LS6 Patriot 2s, injectors and 92 Fast to a LS3 top. I'm still researching into this but from what I've gathered, I need L92/Ls3 heads and a C6 LS3 intake, fuel rails and injectors.

I don't think the vette intake will choke up my 408 like my heads.

Is this all I need?

smok'nZ

iTrader: (160)

i think holly is the on tb you dont have to buy a bracket i got a bracket from scoggin for 35$ you will need there L92 head gaskets 40ish,what pistons are you using? will there be enough ptv?

Pwebbz28

iTrader: (31)

dont forget the valve spacing is different. PTV clearance could be compromised

RyanSws6

iTrader: (72)

Yeah I've got -10cc Diamonds. I've checked no PTV issues. Will need to use a thinner head gasket since the LS3s are 70cc.

WKMCD

iTrader: (2)

You may not like them with the cam you're running. Do the math on your CR. Even with a thinner head gasket your Cr will be pretty low.

Just my $.02

RyanSws6

iTrader: (72)

I agree, with 70ccs from 64 the CR would suffer. I'll have to get them milled. Since the head is more efficient, I won't need this type of cam, smaller is better. Am I right or wrong??

smok'nZ

iTrader: (160)

have someone spec you a cam and are you getting them milled to 64cc? and are you gonna get them ported or leave them stock?

Hamrdown

iTrader: (25)

Almost all ls3/l92 heads use performance cams with 16 degree splits from comp cams. They say that is what works best with these heads. I would talk to Pat G. I would choose a cam that would bring your dynamic compression ratio up and that can make up for the loss in static compression ratio. Are you going to put stock heads on or have them ported? TEA has an awesome set of ported heads. Typically worth another 30rwhp over the stockers. Also I would keep the 92mm tb that you have but for sure get the tb bracket from Scoggin D. After selling what you have how much if any are you looking to spend on what your wanting? Because if it's very much you may be better off keeping your top end and selling your heads to put toward a set of Trick Flow 225 or 235 heads.

smok'nZ

iTrader: (160)

he would have to sell his heads and fork up another 1500-2k for tfs 235-afr 225+a new cam either way

Hamrdown

iTrader: (25)

Personally if it were me since you already have a Fast 92 intake I'd just upgrade the heads to a set of TFS's. It's a lot easier than changing up your entire combo.

RyanSws6

iTrader: (72)

After selling I may have to spend max 5-600. I think its worth it. I have a local shop who has ported/milled LS3s with the hollow valves, TI and .680 springs for less than 1500!!!

I spend HOURS on the PC yesterday doing the math and #s. Even after selling my heads buying afrs I'd be out more $$ was I would by getting much better flowing and valves LS3 heads. Yeah I'd have a OE LS3 intake for a bit, but can get a LS3 FAST later.

Guys I think this way, Camaro SS with LS3, just with a couple mods they're at almost mid 400s. With all the $$ I spent, the newest tech is going on my car. I'd rather go LS7 but I feel this is a compromise.

Hamrdown

iTrader: (25)

Sounds good. I'd do that and just get a better cam suited for those heads. It ought to scream. I just wanted to be sure you weren't putting stock ls3 heads on for all of the trouble it would take changing everything up. But $1500 fully assembled is a good deal on a ported set with those springs and valves.

Ryne @ CMS

iTrader: (10)

i suggest a cam roughly around a 234-244 on 114+2

TT632

iTrader: (3)

Not sure if it was mentioned above, but LS3 rocker arms will be needed also. If your worried about losing some static cr, advance your cam timing with your existing cam a couple of degrees to up your dynamic cr.

RyanSws6

iTrader: (72)

For now, I'll do the top swap then cam. I did order the rockers.

What's this about a TB plate??

I don't have an adjustable cam gear, do I have to get one to advance the timing? I thought it could be done via tune. My specs are close to those but not on the money. I figure as the new Camaro get modded, there will be many cams available soon.

SLOC5LS6

I agree, doug (alln_c5) has a 402 w/TFS 215s/FAST 92 making 541rwhp..
I'd slap some TrickFlows on there before I slapped some LS3s on there.

smok'nZ

iTrader: (160)

well since he already sold his intake and bought rockers there is no turning back now

but i vote to get your LS3 intake ported for 300$ you might need the extra 10 rwhp to reach your goal

Hamrdown

iTrader: (25)

The plate I was referring to is the the cable bracket. The ls3 intakes do not have provisions for a bracket to be bolted on since they come from cars equiped with a drive by wire tb. Scoggin dickey has one that I believe bolts from the head to make your cable drivin set up work.

TT632

iTrader: (3)

You will need get an adjustable gear set if you choose to go that route, Its purely mechanical. You are just phasing your camshaft so the intake valve closes sooner on the compression stroke and you capture more cylinder volume. The down side is all other valve events also occur earlier.

The LS3 heads "as recieved" go flat at 600 lift, so your current cam is not a bad starting place. Good luck!

Jason 98 TA

iTrader: (4)

What pistons are you running? We need to make sure p/v is good with the larger valve. We offer cnc ported LS3 heads with our upgraded spring for a very compareable price to what your considering. As you guys have probably seen we've had plenty of over 650 flywheel hp 408s with PRC LS3/L92 heads & TSP custom camshafts. If we can help you in your project give us a call. I'd be happy to work you out a very competitive price that will help get you to the power output your looking for!