80cutlass350rocket

So first off hi everybody my name is Ed. I have recently acquired a 1980 oldsmobile cutlass brougham sedan with a swapped rocket 350. Block number 3999558 2 i think. I know its a pre 76 block not sure if i quoted the code correct. Im not new to cars building them or anything like that just new to olds and i know theyre a little special. Heres where im hoping some of you old school olds builders can help me. Working with a hypothetical $3000 budget ive come up with 2 possible builds. One is n/a w/ a little bit of bottle. The second is a rear mount turbo setup. Before you think im just another person with pipe dreams of a honda priced 10 sec car believe im well aware of the endeavor facing me down. I have plenty of automotive knowledgeable friends and know a few welders. What i dont know are people who know about small block olds. Under this im gonna list both parts compilations ive come up with so far. Besides wondering what the stock lower end can handle and where the weak spots are, id like to know if im forgetting any parts. And whats the best duration cam for a turbo setup.. im looking for around 600whp..
1. N\A with some spray
Edelbrock performer rpm intake mani
Lunati bracket master 2 290/300 .496/.520
Edelbrock performer rpm heads (i have #8s)
Nitrous express 100-250 kit
Edelbrock 800cfm avs thunder series.
And all gaskets and bolts.. didnt mention bottom end becuase i dont know the weak spots.. on paper it adds about $2900 every thing considered.

2. BOOST!!!
Aeromotive uni bypass regulator
Might demon b/t carb
Holley jet kit
Electric fuel pump
Wideband boost gauge egt
Turbo carb hat
And what would you recommend for a 600hp rear mount set up as far as the turbo itself goes..
Once again didnt list bottom end because not sure..
This adds up to around $2500 all things considered..

The only reason im leaning more toward turbos is i already have the low comp #8 heads, and id just be adding parts. Where as if i go all motor id have to replace everything ive bought for better parts. With the turbo itd be more future upgrades if that makes sense. Any ways any help would be greatly appreciate.

captjim

The stock Olds bottom end is not holding up to 600 RWHP, or even close to it, so factor around $3000 in the bottom end. Rods are generally considered the weak link, but in a boosted application you will want forged pistons and looser clearances.

80cutlass350rocket

God thank you HahHaha this is what i wanted to know.. so what do you think the bottom end could handle in factory form? This is gonna be a long project so if I could just get it up and running even on 5 pounds id be happy till i got the bottom end done.

Nop

https://classicoldsmobile.com/forums...d-support.html

80cutlass350rocket

Now maybe its because im coming from a supra crowd where 800whp stock internals arent unheard of but am i really to belive a fully forged lower assembly is good to 500hp? Seems a little... off.. maybe i read into wrong? Im not looking to break records the car just weights a ton and i want it to be scary on the street hahaa.. but thank you for the link def a good read.

DENT

Welcome to co , you want 600 rear wheel hp ? Has your engine bin rebuilt with some up graded parts? Pretty tall order for a stock 350.
With that goal in mind you probably want to install a bottom end griddle also. If it was mine i would find out what year the engine is and do some research . Just my opinion.

80cutlass350rocket

Lol well now you opinion just earned you a ticket to helping me.. all i know is its 1980 cutlass sedan brougham. Stock was a 260 then somewhere swapped to a pre 76 350. From what i can tell unless its factory it has a delco hei distributor and other little name brand tidbits. Now every gasket leaks oil so im not sure when the last time it was rebuilt is. The block code is 3995558 2 or close to that.. #8 heads and egr intake manifold.. any ideas on year? Also has headers. Not sure of brand but the mating surface is raised from the flange(if you understand that) so im assuming there not very good.. but they work..

80cutlass350rocket

And thank you for seeing the horsepower goal im going for amd instead of telling me its impossible actually pointing me in the right direction.

Shanghai Smith

I have a 403 in my 85 Cutlass. It cost me about $4000 to build the engine and more than that to build the rest of the car to handle the 403. My best time at the track is 11.48 with a 150 shot.
Here is a link to my thread about the engine build. Not a lot of technical data in the thread, just my experience of building the engine.
http://www.oldspower.com/vb/showthread.php?t=57330

DoubleV

I think your goal is possible but requires the entire engine to be rebuilt with quality performance parts. This alone will cost you some coin. Then you have to pay more for whatever power adder you choose to go with. Then you have to consider all the non engine stuff that goes into a high power car as well. In the end, this whole thing is going to cost you a small fortune so if you're not willing to jump in with both feet then you need an alternative plan.

Forgetting about HP numbers, what do you want it to run at the track? How streetable do you want it to be?

cutlassefi

Use a DX block, don't bother with a stock 350 block for that kind of hp.
Use the 425 crank, any aftermarket H beam rod, preferably for an LS, they're centered like the Olds rods are. Then a good 2618 SBC off the shelf piston. From there spend the rest of your money on the remaining pieces but figure about 5K+ for the short block. And with a DX 600 is nothing, you can make stupid power with those if you want.

And as far as a cam goes, a single pattern is typically good for a single turbo, a reverse pattern for a twin turbo.
Hope this helps.

80cutlass350rocket

Thank you guys for really helping out. Horsepower aside im looking for lows 12s high 11s.. but im more after a high trap speed because i doubt itll see much legit track lol. So far the idea os rebuild the th350 22-2400 stall converter 3.08s in the back.. streetable is a relative term as im 22 im willing to sacrifice alot of comfort to have a fast daily. Im also not new to turbo charging and i realize theres alot of things i didnt list that i know are required.. so for the sake of being different about whats the limit before reliability is ruined?

80cutlass350rocket

And belive me i understand my budget is gonna have to step up a little i know good parts arent cheap.. whats a good trim/a.r. for a remote on a 350.. i figure a 60-70 trim with like a .9x exhaust housing.

DENT

You did the wise thing , you asked questions . Never any harm in doing that.

cutlassefi

What block/crank? Stock 350?

Smitty275

If you have a 350 Olds of any year the internals are not fully forged. Only the rods are forged. The crank is cast iron and the pistons cast aluminum. If you think you'll actually stop at 600hp the gas 350 block is useable but only because its a turbo app which is easier on the bottom end for some reason. You'll need a forged 330 crank and pistons built to run a turbo. I'd also switch to a good set if SBC rods rated for the power level.
If your like any other 22yr old you will want more out of it eventually. So start with a D or DX diesel block and do as Cutlass EFI recommended.
Personally I don't buy into the low compression turbo build concept. Put some wind in it to begin with. A solid 10.5:1 is not a problem. Then add boost to get the power you want from their.

olds 307 and 403

Your engine is 73-76. You need much steeper gear than 3.08 gears to reach your goal. Probably more converter too, maybe boost throws all that out the window? With your stock heads and forged flat top replacement pistons, you will be just under 9 to 1 compression.

captjim

Are we having pancakes?? LOL

80cutlass350rocket

The low compression is to save wear on the bottom end and reduce the risk of detonation on pump gas. And yes as of right now the motor is stock. And if i wanted over 600 id sell the setup and turbo a 455. Once again thanks for the advice guys.

70cutty

Sell the setup, drop in a LS and turbo or spray that. At least you don't have to worry about it and it will get you to 600hp cheaper.

Olds92

An LS? Hah. This is an oldsmobile forum. So tired of chevy.

Anyway. Dude youre gonna have to forget the 350 block and get a dx block.

captjim

All due respect, an HONEST 600 RWHP with an Olds is going to run you close to ten grand. Even with boost and N2O, you gotta have the head flow and bottom end.

jag1886

$3000, I'm sorry but you need to wake up from what ever dream you are having. Not to be mean but you are off the ball.

70cutty

I am not trying to start an argument here, just trying to help OP achieve what he wants for less money. I have done few LS builds and sorry but it's most economical way to make power. It would be wrong not to point him in a right direction. He will spent 10-15k to achieve 600hp on olds. For half of that you can do an LS and it will be way more reliable. Sorry I know it's a oldsmobile forum and I would never do that to my cutlass but it is what it is. I just bought a 16k miles LS3 with transmission and complete wiring for 3k. Spend another 3k and 600-700hp easily. JMO.

cutlassefi

Wrong thinking. A DX is way more durable than any 455 block.

Redog

Somebody else already asked, but what do you want the car to run in the 1/4 mile? The 80 Cutlass is small and light, I want to say 2800 lbs, you won't need 600 horse to get that thing moving

I think you could build upto 450-500 range and put the car on a diet.

DoubleV

The OP has stated he's looking to run high 11's/low 12's so is obviously mistaken on the amount of power needed to accomplish that goal. High 11's/low 12's with spray is very doable on a 350 but certainly not a stock one. Then there's the rest of the drivetrain too. 80cutlass350rocket, the fact is you need a much bigger budget.