mw66nova

iTrader: (13)

well guys, i think i have just about met my limit with the 305. i would like to get it a little closer to that 12 second mark if i can with a looser converter and my already installed 4.10 gears. but i think as far as mods go to the motor, i am done. maybe an msd box.

here is my question:

i am looking to run a ~9.7:1 c/r 383 for the street. i was looking through Scoggin Dickey's site last night and noticed the "Vortec Head Kits". i would be getting the one with the L31 heads, Performer RPM and the upgraded springs to handle .550" lift. the car will be driven 3-7 days out of the week depending on what i feel like and so gas mileage is an issue, but not a limiting factor. i would like to be in the 12's with this combo. what would ya'll suggest for a cam? i would like it to be off the shelf. it may see an occasional hit with a 150 shot to break into the low 12's high 11's. also, what are ya'll running for rocker arms? i have been running aluminum roller rockers on my 305 for about 1 1/2 years without any problems so i am not afraid to put aluminum ones on. think a 750 vs will feed it fine? converter stall speed is yet to be determined, still have to talk to ATI. sent them money, just waiting to hear back from them. input on stall speed is appreciated too...

mw66nova

iTrader: (13)

what about these rocker arms? will they work well? what kinda clearancing will need to be done, any? 1.5 or 1.6, doesn't matter a whole lot to me, just which ever one that needs the least mods to make work.

http://www.sdpc2000.com/catalog/523/...ocker-Arms.htm

also, valve size for the L31 heads?

forums_suck

those rocker arms are just crane energizers with gm's name stamped on em so your paying for the name,shouldnt need clearancing as long as your not running large diameter valve springs.

As far as off the shelf cam goes gm makes some great ones,you could try gm's hot cam which is used by alot of the ZZ4 guys and you won't need huge valve springs to run it.

Your rockers that you have now should be just fine,and the 750 VS carb sounds like the way to go with the automatic.

If you check out sallee's chevrolet's sight they have a good message board there that has lots of info on off the shelf cam selection and other good stuff too or even better just give them a buzz they're a great bunch over there and can answer all your questions

five7kid

iTrader: (14)

Another 305 defender bites the dust...

mw66nova

iTrader: (13)

i thought that the rockers for a vortec head were self aligning. mine are not self aligning.

littleTAkid82

We used a comp solid roller 242 dur @ .050 with our ported vortecs, lift is .587 with 1.6 self guided alum rockers, rpm Air Gap, 870 street avenger, made 477 hp at 5500 505 lb ft 3500-4500. Springs were Comp Behive 29218.
Dale
www.schwartzperformance.com/ygen.htm

ridecamro

i thought vortecs had a limt to the lift they could take even with a lager diamter spring and a one wiht more lift to it. it's like .500 at max or so i've read and been told so cam selections are harder to select. correct me if i'm worng which i probally am

Stekman

At approx. .450" of valve lift, factory setup, the bottom of the retainer slams into the top of the guide boss, physically halting any further lift. If the installed height of the springs is increased and/or the guide boss is milled down, then this is not a problem.

IROCaholic

Comps XE268 and a 2400 stall combined with the rest of that combo should easily put you in the high 12's. Although if you can go with a roller cam I would defenetly look into the LT4 hot cam GSGZLR was running low 12s with it and unported vortec heads on a 350. Good Luck.

mw66nova

iTrader: (13)

anyone know if the upgraded heads from Scoggin Dickey with the higher rate springs have the guide bosses milled for more clearance?

IROCaholic

Im pretty sure they are fully preped to handle .550.

five7kid

iTrader: (14)

You might want to give them a call. I've never seen anything that indicated they put screw-in studs in them.

If you've seen that, let us know.

mw66nova

iTrader: (13)

since i am going with the performer rpm intake, don't you think the performer rpm cam would match nicely?

specs:
lift @ valve: .488" i/.510" e
duration @ .050: 234*/244*
lsa: 112*

i think this would give the car a nice little thump sound to it and it should give a pretty nice power band spread. give me some thoughts guys.

CamarosRUS

in my small block chevy engine buildups book by chevy high performance a 355ci small block made 422hp at 5700 rpm and 418 ft lbs at 5000 rpm with a lt4 hot cam kit vortec heads, 1.6 rr's, a single plane manifold and 750 cfm carb. the dual plane manifold didnt give as much peak hp (412 at 5600) but had slightly more power and torque until 5000 rpm's.

this combo is tried and true, with the rest of the car capable your easy into the 12's. 11's with that spray.

on a 383 and bigger (1 3/4) headers you are closer to your mark, easier.

but since you are building a 383 you might just find a cam more suited to the displacement.

incus86

they will, because they sell them with the hotcam in one of their crates.

incus86

i have also heard multiple claims of 400+ hp with lt4 hotcam, vortec head and carb. if you stick with tpi you won't make as much hp, but much more torque.

todd200

Actually, they are Crane Golds with GM's name stamped on them. I've owned both at one time. There is no comparison side by side. The Energizers were much larger, but looked much cheaper.