newschool72

iTrader: (12)

Guys , Im trying to decide on a direction with my LS3. Right now its running good in my 72 Camaro but I want to take it up a notch .
My choices are a cam upgrade and a really good set of heads( Texas Speed aftermarket 250cc LS3s) and the GMPP dual plane intake or a 418 LS3 shortblock with my stock LS3 heads and the Vic Jr intake thats on the car now. Both combos would have a cam speced by Pat G.
This wont be an all out ,max effort setup, but a streetable, AC,PS,PB street car that will go deep 11s NA , hopefully. The car has stiff suspension with big aftermarket sway bars,etc,etc and a set of mickey thompsons to hook it at the track, so im concerned that the stroker option might have too much torque to hook with my road suspension.
Any help or advice would be appreciated. Thanks

newschool72

iTrader: (12)

WOW! No body has an opinion? Im not asking for the hand of God to give me the right answer, just an opinion or two to help me figure this out. Thanks

Dyno Junkie

Not sure if you are running an auto or manual?

Unless your car weighs over 4,000lbs if it's an auto it should already be in the 11's.

Our Monaro weighs 3,880lbs with me on board. So far it has run a best of 11.199 @ 121mph.
This is a crate LS3 with 231 239 .617 .624 113 Comp Cam, 25% UDP, 90mm throttle body, 1 7/8" extractors into twin 2 1/2" system, stock 4l60e with 4,500rpm convertor and 4.1:1 diff gears.
Car is set up on Tein coil overs and runs down the track on factory 18" x 8" alloys with Mickey Thompson 265/40/18 radials.

ringram

Displacement for torque, heads for power.

If you want more low end torque go with the stroker. If you want to wind it up go with heads and cam. Of course there is more to it than that, but its a fair start point.

If it were me Id go stroker because on the street you will appreciate the torque more.

Plus you will need a cam in there anyway. The stock LS3 heads can be changed later

DaleTx

I would say go with the 418 LS3 with LS3 heads and the Vic jr or a GMPP single plane intake. I have a stiff suspension set up similar to yours, and a 427 LS2 with single plane intake. On my car the drivability is great from tip in through the mid range and very strong on the top end. Lots of fun to drive. Even with the single plane it is still difficult to hook up in the lower gears. There is still plenty of power in the low and mid range... very linear power band. Drivability and deep 11's NA will be no problem with the right cam. If you check page 4 on my build thread there is an idle video and short driving video with this set up.

01_SuperSlow

iTrader: (7)

I say go for the stroker and a matching cam for the extra cubes.

newschool72

iTrader: (12)

So majority says stroker so far. I really like the idea of a stroker too, but it sure would be an easier change over doing a heads swap. No pain ,no gain i guess. The trans(2004R) has to come out for a valve body upgrade and a new yank converter, but the motor mounts are a nightmare to get lined up.
The car weighs around 3300lbs and like I said above ,its an auto and has 3.42 gears in the rear. I thought id get a good 35-40ftlb boost with the heads and dual plane intake and have read that the extra 40+ cubes would be worth about 50ftlbs.
Keep the opinions coming. Thanks.

litle88

iTrader: (20)

I would go stroker as well, that Trans will definitely need alot of beefing up IMHO.

You can always call Comp to spec you a cam for free, ask for Gabe Gray?

Your stock heads will be just fine with a stroker, naturally a set from LPE, AI or WCCH would be better but there's always next season for that. Just my .2

Tainted

iTrader: (9)

Stroker ftw

Any mods you do after the bottom end make for even sweeter gains

newschool72

iTrader: (12)

The trans has the 13 vane pump and other upgrades that bring it up to 550 ft lbs and 600 hp. It will be on the edge of holding the stroker, for sure. I am thinking that I may just do the dual plane intake and the trans upgrades first, just to see what kind of times it will run.
I am running the FAST EZ EFI on the LS3 right now and it runs rich at idle. I think its because Im not building any velocity with the wide open Vic Jr intake and those 260cc stock heads. I have a comp LSR269 cam in it now(607/621-219/235 at .050) that I thought would help with the low speed air, but it dosent seem to help much. If I could speed up the air with the longer intake ports of the Gmpp dual plane intake so the FAST would work better and run in the 11s with the setup now, it may be the most economical way to go.
I built this car to be able to drive it anywhere, in comfort, and run with any of the latest muscle the factorys are putting out. Id like to be able to run legally at the track without a rollbar, but right on the edge,11.50s.

litle88

iTrader: (20)

I believe you have the wrong cam in there with that Vic jr intake, get a 3 bolt cam gear and a cam in the ~108 LSA. Call Comp I'm pretty sure those intakes like tight LSA's.

newschool72

iTrader: (12)

LOL...That is a Comp recommended cam. I wish I had remembered the specs on the cam a guy at Comp had recommended the first time I called. Dude sounded like he knew his stuff on LS cams. I lost the specs he gave me and called back a few weeks later and the numb nuts I got that time convinced me the LSR269 with a 113LSA would be the cam for me.
Im running big brakes all around and need really good vacuum, so Im not sure I want to tighten up to a 108. I will probably go to the dual plane and hope the cam likes the longer runners.

Sales@Tick

iTrader: (3)

Dual plane or single plane?

newschool72

iTrader: (12)

I have a single plane vic jr, now,but am thinking about going to the gmpp dual plane for the LS3 heads.

Sales@Tick

iTrader: (3)

Keep the single plane, do a heads/cam build.

We made 515rwhp/475rwtq the other day with a VERY mild build. Small 230/240 113lsa cam, budget port work, 11.0:1 CR, un ported Fast 102, small 1x3/4" headers, stock h-pipe, stock resonators, 2x1/2" exhaust etc. It was a DD so it was far from max effort.

I don't see why 550rwhp couldn't be made with a single plane, full CNC port work and a cam matched to the heads and intake along with more compression.

newschool72

iTrader: (12)

Do you think a set of texas speed LS3 heads( aftermarket 250cc port) with a mild cam in the hi220s/low230s intake and about 10 more degrees exhaust would make better tq # at the expense of a few HP # up top. Mild cam events will be important because I could take this car on long hauls of 400+ miles and really need good street manners. I dont think opening up the stock LS3 heads would be a good idea on a 6.2. I think at 260cc, they are too big now for low end power. That is what impresses me about the TS heads, they flow huge air compared to the stock LS3s, but have runners that are 10cc smaller. Seems like a win,win.

Sales@Tick

iTrader: (3)

I think the 250cc PRC LS3 heads are very nice and will definitely do what you want to do. I could do the cam for you that would work great with those headers and your current single plane intake.

The great thing about the budget port work is not porting the intake runner. It really helps in getting the intake/exhaust% up and balancing things out. Keeping the same size intake port and valve is what makes that cnc work so intriguing for a 4.030-4.065 bore.

Either way you're going to get what you seek.

newschool72

iTrader: (12)

Im on hold for the short term, I hope,lol. Im selling my old school 68 camaro that runs 11.30s with a SBC 406. When its gone I want my restomod style 72 camaro to give me the straight line acceleration that the 68 has, but with the handling and comfort I already have in the 72. A do all hotrod.
I will get with you on the cam soon, but I am really serious about good vacuum for the 4 piston discs on front and back. It also has Vintage Air, so a strong and stable idle is important too. The FAST EZ does step the idle up when the AC comes on, but I dont want issues with transition when the idle steps up. Thanks Martin. I will let you know when Im ready.

Sales@Tick

iTrader: (3)

I've got you taken care of!

Streaty383

I personally don't think you can beat a good stroker set up with a cam to suit your build, you can get a very good set up from tsp for about 3.5 k and the standard heads will be five with some one who knows what there doing with a Cnc machine, the constant power and tough tourquey nature makes them a great streeter with all your creature comforts. My ls1 is a 383 build with 11.5:1 comp, cam and heads machined making 460 rwhp and 884 ft/lb