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450 horsepower out of my 1969 oldsmobile Rocket 350??

  
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450 horsepower out of my 1969 oldsmobile Rocket 350??

 
olds350 olds350
New User | Posts: 2 | Joined: 10/11
Posted: 10/04/11
02:38 PM

I have a 1969 olds 350, it is all stock. I will be getting it rebuilt soon and I would love to get 450 horsepower out of it. What rebuild parts will I need to get this done? Stock it was supposed to be 310 HP. It has a 4 barrel carb. Thank you!  

Budnicks Budnicks
Enthusiast | Posts: 676 | Joined: 10/10
Posted: 10/05/11
08:22 PM

olds350 1st off welcome to the Car Craft forum.. 1st. "A Quality Machinist" would be my number 1 criteria, then 2nd. would be free flowing exhaust & headers, 2a. a set of good flowing ported {minimum of 220cfm flow rate} @ {est. 2.06 HP X # flow rate} quality cylinder heads {preferably aluminum}, 2b. a "quality" appropriate camshaft {minimum of 0.500" net valve lift}, that matches you needs with all matching components, push rods {proper length}, springs, valves, retainers & locks, 2c. higher ratio {1.6:1} or at least accurate {1.5:1} ratio adjustable rockers, 3rd. a set of forged 10:1-11:1 compression ratio pistons & Zero gap or Perfect circle ring set {with a properly finished & truly round bore}, 4th. a well tuned, properly sized & free flowing induction system {intake & carburetor {Holley DP} or Injectors etc.}, 4a. a proper sized fuel pump, pick up & plumbing, minimum #6 {3/8"}to #8 {1/2"}, 4b. a K&N or equivalent gauze type air filter & base, 5th. quality gaskets, especially the head gaskets, 6th. a quality hotter ignition system, to be able to fire the added fuel at higher RPM's & higher fuel flow rates, 7th an internally balanced bottom end with quality, machine work, bearing, rods & quality hardware bolts nuts & studs etc, 7th. a quality properly sized & pressure/flow oiling system, oil pan, oil pump, pickup & filter etc.... That will get you in the ballpark with 93 octane pump gas... That's pretty much the formula for any basic performance 101 engine, no matter who's make, Olds, Chevy, Mopar, Pontiac, Buick, Ford etc. or size of engine, the bigger cubic inches, the easier it will be of course, there's always turbocharging or supercharging also...  
"Fill Your Library Before You Fill Your Garage" Good Luck  "Budnicks"

tuffnuff tuffnuff
Moderator | Posts: 1376 | Joined: 12/09
Posted: 10/07/11
10:10 AM

Welcome to the forum, 450 horse out of a 350 is a tall order.
I agree with Bud's suggestions and aluminum heads are a good place to start.
This will not be a budget build.,. but it can be done if you have the funds.

Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

olds350 olds350
New User | Posts: 2 | Joined: 10/11
Posted: 10/08/11
04:57 PM

Thank you for the info... Maybe I will look at maybe going 400HP instead of 450. I dont mind spending some money but not a fortune.  

Budnicks Budnicks
Enthusiast | Posts: 676 | Joined: 10/10
Posted: 10/09/11
01:46 PM

Your welcome, yep it's not cheap, $10-$15 per/hp minimum, maybe just some N20 for a little extra added power after you do a quality performance rebuild, I still prefer the good base line build before N20, even if your going to use N20, it's cheap insurance,to have a bullet proof bottom end & free flowing top end, will be needed on any type of performance type build...  
"Fill Your Library Before You Fill Your Garage" Good Luck  "Budnicks"

460-BBF-Turbo-In-CC 460-BBF-Turbo-In-CC
Guru | Posts: 1163 | Joined: 10/03
Posted: 10/12/11
10:38 AM

450 out of a 350 Olds is only 1.25 h.p. per cube (79 h.p. per liter).

Assuming that this mill has decent leak-down numbers . . . and you're not stuck in one of the states follwing CARB emission rules . . . I'd recommend taking a page from Oldsmobile's past by turbocharging the engine.  

At that power level, we're talking about a fairly stock-type set-up using a blow-through carb, boost-timing retard module, mild camshaft upgrade, and some water/alcohol injection. And you wouldn't need an uber-expensive state-of-the-art turbo to supply enough air for 450 h.p. Because your engine has high compression, you're going to be boost-limited on alcohol-assisted pump gasoline.

Something along the lines of what Mike Sitar did with his JY 351W in a Thunderbird back in 1996 (albeit with lower boost) would hit your goal with a minimum of expensive aftermarket parts. See www.toohighpsi.com  

Even with the dodgy strength of the stock Olds short-block, I'd take the risk that a home-brewed turbo set-up would work well for less than the cost of an "all motor" 450 h.p. build.  

Note that if I were doing an all-iron high-compression turbo build, I'd run a split fueling system (93 octane in the primaries, alcohol or E85 in the secondaries and and a supplemental alcohol/E85 injector under boost) I would also charge-cool it even at single digit boost levels.

Of course, if you're having it rebuilt anyway, reducing the compression to smogger levels would allow for more boost on pump gas and higher average cylinder pressures under full-throttle.  
--------------------------------
460_BBF_Turbo-in-CC (formerly Dr511scj) "This guy has no life other than posting endlessly on carcraft.com." -- Car Craft, July 2005
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October 1, 2003: " I'm thinking a couple of...turbos, blowing through an old Powerstroke intercooler...on a Super Cobra Jet-head 460 would be mad cheap and make sick power."
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"I have no problem with your...talking to several versions of yourself...or pointing out our failure to do a turbo story ...." --Douglas "CC/Rambler" Glad

tuffnuff tuffnuff
Moderator | Posts: 1376 | Joined: 12/09
Posted: 10/13/11
06:52 PM

Mild boost is a great alternative.,. at 14.7 pounds of boost, displacement is doubled.
So at a modest 4 to 5 pounds it would be about one horse per cube.
That is very doable.

Smile  
When The Flag Drops.,.

tuffnuff

The Bull ***t Stops.,.
tuffnuff

P. Engineer, Engine Builder

oldsfreak-#002 oldsfreak-#002
User | Posts: 218 | Joined: 03/09
Posted: 03/18/12
10:30 PM

speed pro flat top pistons to give you compression, you probably have #5 heads, they would need to be ported to flow around 260-270 cfm with big valves, give jim a call at j&s machine, take a look at their website for prices, and a custom cam would do the trick with a good intake, the edelbrock performer rpm of the holley street dominator  
"Racing isnt a hobby, its a way of life"

JDerek JDerek
New User | Posts: 21 | Joined: 12/11
Posted: 03/19/12
12:28 AM

Breathing will be the key. No doubt about that. You didn't say where you wanted that 450. To the wheels will cost a fortune and more than likely wouldn't be all that streetable. As for on the Dyno, very doable. Even then you would feel the difference. Your top end will be where you need to spend the most time and money though. There is a place for Olds junkies. Maybe you've heard of it. Mondelo's. Joe has left us but the company is still around and they will have the best advice for you. As with anything not a 350 or 302 you will spend more but hey, it's an Olds. Arguably some of the smoothest engines of all time.