well i'm gonna be runnin a lil higher comp due to a busted valve head goin through my motor...but i've never had it dynoed but i contacted nick norris at nu-tek and he said it sould be puttin down 440 real easy to the wheels hopfully more when i'm runnin higher comp and a dif cam after the rebuild. but as for the gas i just ran 91 octain in it and performed just fine...

 

IMHO no need for a 383 to do this.....

Might not even need aftermarket castings, but really good LT1 castings. For example I have a set of LT1 castings in the shop now with 2.05 valves in them (which requires new intake valve seats) that flow 284-287cfm. Now mid you these heads are not cheap but they do the job better than what you get from AFR for the same money. Port size is smaller and the port job is much better. This is the first piece of a $6000 puzzle.

I would almost say that a stock short block could pull this off, with stock head castings. A bottom end is going to eat up at least half the budget, and there is no HP in a bottom end when you have a budget. Big dollar race motors, yeah there is lots of power down there but it's not cheap and costs lots of money.

The next thing is the cam AND valvetrain. 450rwhp needs good parts, and a cheap cam kit is obviously not getting it done. You need to get the motor to make power at 6300-6600 to get where you want to go, not die at 6000. So here is another part of your budget. You could really put 2/3 to 3/4 of your money in the cam, valvetrain and bottom end, and have not enough left over for a set of heads to get you to 450rwhp.

Now throw on that tuning, and the rest of the little parts and $6K is a big time stretch.

A head/cam/valvetrain/intake/tuning if you have all the bolt ons should be able to get you there in $6K and you don't even have to yank the motor out of the block to do it.

Bret

 

Yeah, stick with the 350. With an M6 you'll need ~520 at the crank. That's doable with the right induction and camshaft, just as Bret said.
Of course, if you do your own work (assembly, fitting, etc) then things get a bit less exensive for ya. Don't skimp on machine work though. Its that stuff that you can't see with the naked eye that will cost you power.

Good luck.

-Mindgame

 

Bret and Mindgame, what is wrong with the cast steel cranks, going with one of these will dramaticly reduce the bottom end price. The manufacturers cailm they will hold up to close to 800 hp (I havent pushed that but maybe you guys have).

My Eagle cast steel crank took very little to balance with the stock flexplate and stock type dampener.(they had to add 2 peices of mallory metal)

My buddy has the Scat crank and it balanced even easier.

My prices I have found are as follows.

Scat cast steel 9000 series crank $219 shipped to your door.
Scat H beam 4340 rods (from Northern auro parts ) $259.
SRP Forged pistons $520
Rings $110
Bearings $100
Machine shop bill for balancing,boring and honing to pistons,clearancing,vatting,installing cam bearings and freeze plugs,zero decking, installing splayed caps,and installing pistons to rods. 810 (including tax)
Oilpump (mellings) 30$

I assembled this myself, so we have including 12$ for paint
for $ 2060
The left over almost 4 grand will buy some nice heads and a good valvetrain.
Of course odds and ends may put you over, but lets just say he buys some afr 210s and has them ported that would be close to 3 grand.
cam, lifters, springs and pushrods would eat that last thou, unless you can find some real good deals.

I realize that the 4340 steel forged crank would handle more power, but with a goal of only 450 rear wheel , wouldnt the cast steel do the job?

 

No problems with the cast 383 crank here WS. For this level of power, cast will work fine. A 383 is a good choice too, the point was simply being made that it isn't a necessity. It will definitely be a milder, more streetable engine though.

On the pro-383 build side of things.... it'll make its power 600-1000 rpm lower in the powerband. So that in itself means less rpm for valvetrain components. Not to mention it'll likely make a good deal more torque, all else remaining the same. Good thing if you can get it to the ground..... better car setup to cut low 60' times.
The low side is, to make the ponies that 383 is going to need a much better cylinder head than the 350. That's where a lot of these builds aren't making the power they should IMO.

So it all comes back to the heads. But yeah, you can do a cheap 383.... I wouldn't even spend the $500+ on a set of pistons, not when a set half that price will do. That's more money to the cylinder heads. Which brings up the fact that I wouldn't use an assembled head. I'd buy bare and fit it with the components I want/need. But that $250 I saved on the pistons would be put to good use there.

-Mindgame

 

The most compelling reason I chose to build a 383. This and the fact that it will make more torque with all other things being equal.

 

The 383 will make more TQ given the same setup, heads and intake. Then again 465rwtq out of a 355-358 is not that hard and most guys don't get that with a 383 LT1, the problem is the intake manifold.

Nothing wrong with the 383, and nothing wrong with a cast crank like a Scat 9000. I would just spend all the machine work and parts cost from the bottom end on the rest of the motor.

Bret

 

I see , I misunderstood you guys, I went back and read through again and I get the direction you guys were going.

I do have to say though , the 383 I built for my car has lived well up to expectations. In the future I will have my heads done by a pro to get more flow and upgrade my valvetrain, but as it sets I have so much torque I could rent it out!
From any speed you can move the pedal to the floor and set yourself deep into the seat, watching the speedo move across the dash like the tack!!
Since owning this, if I have the money to sink into an engine I will never own a 350 again for performance on the street and mild track use.

 

i like torque so what would be a good bottem end?

 

If you never ever plan on running juice or the like you can run some Hyper pistons, or you can go with the TRW pistons for 250 a set they are forged, the scat or eagle H-beam rods work,the Scats are cheaper though, and a scat 9000 series crank.

Options you can add are zero decking the block, adding splayed main caps (4 bolt), and that will hold up pretty good to low 6000 rpm blasts all day long. Just cam and head it accordingly.

As a side note, do not neglect the fuel system, go with a 255lph pump and some 30 or 36 # injectors (along with proper tuning)

 

I think it can be done but not to many guys have.

Thats why I went to Joe Overton and went with a solid roller
but I want more than 450rwhp

You have to have someone who knows what they are doing like Joe, Stroker, ect
6k will be tough to stay at as far as budget