1sick-Z

iTrader: (3)

Is there a cam out that will rev to 7800-8k rpms on a forged 346 with a sick set of heads??

if not can anyone custom grind me one???

black00ssFL

iTrader: (24)

Hope you have a sheet metal intake in mind. I'd worry about that before a cam to make power in that range. A custom grind is no problem, and fairly cheap compared to getting an intake manifold to flow enough to back that rpm range up.

Chrome355z

iTrader: (1)

I have to do it... why?

Especially since you say in your sig that you are getting a 408 + Dart Heads this winter???

1sick-Z

iTrader: (3)

sig is old i sold the iron block

even at 7500 rpm would a ported fast 90 accomodate that?? or would i still need sheet metal

as of right now I am still on stock bottom end over winter I am just going to forge that. I just want to get a little more out if it

LS1Z28-00

iTrader: (8)

id say a fast 90 would allow you to shift at that rpm. a sheetmetal would add alot more power at that rpm though. i think most ms4 cams and such can be shifted at 7k with good heads and fast 90.

87silverbullet

iTrader: (11)

Dude if you are going to go that high you are stepping into solid roller territory. A hyd. roller would probably not make it that high unless you have light valvetrain components plus the cam would have to be a sick grind. It would probably be big duration with a tight lsa, but what do I know I mess with turbo buicks, we shift at 5800.

1cdub

iTrader: (5)

been there with a solid roller and ET heads. Pulled good to 8000 rpm. Cam was 262/268 dur. at .050 lift was .734 on a 110. Sheetmetal intake, 90mm tb. Car made 526 to the wheels thru a 6 spd. and a S60 on pump gas. Drivability sucked, and it was hard to tune...I won't do that again.

1sick-Z

iTrader: (3)

yeah 8 grand is kind of high maybe more along the lines of 7500, but your setup sounds sick how was it shifting at 8k ??

dug

iTrader: (10)

sounds like its more expensive to build a 8k rpm 347 than it is to build a 7k rpm 408

1sick-Z

iTrader: (3)

it may very well be I am jst trying to think outside the box and have something a little bit different then everyone else, just an idea.

I dont really think 7500 is that bad though

Randy WS6

iTrader: (69)

I shift my LS2 418cid. at 7400 rpms. on whats in my sig.

Old SStroker

It can be done....already has.

How about a stock shortblock 6.0 with 5.3 heads (good valve job and some milling), a single plane with 4-bbl EFI, stock lifters and rocker arms, a custom hydraulic roller cam, and good valve springs that spins to 7800 every run in a bracket dragster. It has run all season and is at Maple Grove this weekend.

Very consistent 8.70-8.80s in the mid 150s. Not bad for a budget build.

You really don't need to get exotic/expensive if you do things correctly. The cam is a critical component, of course. Manifold choice will determine if you will make power in the upper rpm range.

dug

iTrader: (10)

Isnt the gmpp carb style intake good for 8500rpms?

dug

iTrader: (10)

does he do anything special to have it rev so high? Like oil restrictors?

KMS.1320

iTrader: (1)

haha you guys were the first ones I thought of when I read this. That's some voodoo magic in my opinion to get a stock lifter to last a full season under the valve pressure you'd think was needed to control a valve at 8k. But I know you guys have ways to deal with that. I'm sure if you told me the open and seat pressure I wouldn't believe you (I would though, it would just probably amaze me).

And to the OP, to repeat what was said, yes, it can be done, a ported carb intake would be a better choice than a fast for 8k rpm's, and don't expect to drive it on the street with any kind of manners at all. Won't make power under 4k, and will be a BEAST to tune and idle around in.

PREDATOR-Z

Yeah, it can be done, been there on a hydraulic cam, only exotic thing we used was a Comp Shaft rocker system (what a bitch for cover clearance, ended up getting aftermarket covers and relocated coils, Clears stock covers my *** (as per Comp)). maybe 40/45 passes so far, still holding. 8000 shifts, only once (1>2) though (powerglide)

Randy WS6

iTrader: (69)

I run stock lifters also, shifting at 7400 rpms for over a year now and the only thing ive changed is the valve springs.

Old SStroker

I've heard that many folks who see the engine with stock LS rocker arm covers and coils don't know what it is. I guess most of the competition uses old school engines. From what I know, the car pays for itself.

I'm wondering if the bottom or top end will need rebuilding first, or perhaps fail first. So far so good AFAIK.

Gordon0652

iTrader: (4)

& thats with a 4.100" stroke! niceeeee

Randy WS6

iTrader: (69)

From what Ive seen ,the weakest links in the stock LS1 motors are the piston ring landings , then the rods, and valve springs. The strongest is the crank .I build a 347cid. with eagle rods with L19 rod bolt and Ross pistons and a stock crank and had it all balanced and run tons of nitrous threw it , I shifted it a 7800rpms all day log. And steal the motor is in good shape. I have it on a motor stand as a back up if i need it. The LSX style engines are very tuff. And I will never go back to the old style sbc engines.