I have searched all threads on the subject already, but since I am bored, I decided to start another. I have just acquired a 69 Convertible project, without an engine, and intend to build a big block for it. After all the custom and performance work I did on my 77, I learned two things.

1. Every time you "upgrade" something, the ripple effect is that something else needs changed.....i.e. slippery slope.
2. It cost way more money when you "upgrade" the car.......lots more.

So, with the 69, I have decided firmly that I want to build the car as close to original as reasonable.....not NCRS crazy, but just build it the way Chevrolet did, and capture what the car was in June of 69 when it was built. Not overthink it, or over build it. BUT......given I have NO engine at all, I know enough to know that I can build a big block that looks original, but might just have a little more juice built into it. There is ONE firm point, and I will not budge, I want to use stock GM cast iron exhaust manifolds. NO headers. As soon as you go headers, you no longer can buy store bought exhaust systems,.....and then you are down the rabbit hole of upgrade cost inflation. Plus, I like the looks of cast iron Big Block manifolds. I also want to use factory style big block hood,....not a fake L88 hood on a car without an L88 engine, so I believe that limits my intake manifold choices.

SO.....what I know is that the exhaust system and intake manifolds are big corks when it comes to performance upgrades. My question is to all of you, what can I do to make a big block perform UP TO THE LIMITATIONS of the intake that will fit under the hood and the cast iron Big Block manifolds / exhaust system......OR is it not even worth the effort and just build a stock motor. And when I say performance, I mean torque......I will never drive the car over 70 mph, will never race it, and am not showing off to anyone. These are my thoughts so far.

- Build a 454 instead of a 427, i.e. LS5 style engine just to get more torque. At what displacement does my self imposed limitations be a waste of effort? 454, 496, what? Or just build a 427..
- Aluminum heads for weight reduction primarily........AFR heads with low rise intake and cork exhaust would be stupid waste. Maybe Edelbrock Performer heads, or other lower performance aluminum heads, or is nothing worth doing? i.e should I just build a factory spec'd L36 the way it was built in 69.
- Cam?
- It appears factory 427 parts are extremely expensive just because,....so why not just go 454 LS5 stuff that seems cheaper. I want to control the costs on this project as opposed to the out of control costs I created with the 77.

Get my drift....looking for a reasonable way to enhance performance of an original looking engine, within my self imposed limitations. What do you say?

 

Calling Vortecpro....(hes your guy google him)
Screw paying big $ for a 427. Get a 2 bolt 454 truck block, a set of decent oval ports iron or aluminum
Do a good valve job, bowl/short turn work and a reasonable sized cam, opinions will vary there.
COmpression ratio depends on the cam but assuming you have an auto with 308/3.31 Id reach or a Isky 270 type cam
It would still sound like it had a cam drive well and make tons of torque.

Edit...with a 4 speed you could get away with the 280 mega cam. Midrange is impressive for what it is

Like FT cams in BB it is so simple to make fun tire melting power thats reliable

Love the 427s but face it they are simply too much $$

 

thanks for the input. It will have Muncie M20 4-speed and whatever rear end works best....336 355 or 308

 

A 454 with a small cam and 3:08's would make a great driver and could be budget friendly. It seems the Brodix Race-rite 270's come out on top for Bang 4 the Buck unless you get a great deal on ready to run stockers. I agree on using a single pattern cam for your needs, and it should keep a little more gas in the tank for MORE driving miles/smiles !

 

Given your intake/exhaust decisions camshaft decision will be critical. Check out the factory fast drag car engine builds.

 

Can you clarify what an FT cam is? Never heard that brand name, or ?

 

Flat tappet, Isky cams

 

" I have decided firmly that I want to build the car as close to original as reasonable.....not NCRS crazy, but just build it the way Chevrolet did,"

Putting a 454 in a 69 is about as far away from "the way chevy did" as you can get. No sense building a 69 on the skinny son. The 427 is a far superior motor and driving experience. After all, in 2013 chevy came out with a 427 convertible collector Edition. Can't say they ever considered a 454 collector edition.......

If you want an original 1969 L36 Carb to Pan, ready to drop into your 69. I got one sitting in my garage. It shines like it just rolled off the line. As rare as rare gets!

 

WTF,

how is a 427 far superior to a 454?

454 is basically a 427 with a 1/4'' stroke

427 went to 454 due to emissions in 1970





just build a 454 2 bolt main eng,9.5 to 1 comp,,then look at edelbroke heads/cam/kit,,[cheap and good all-around kit]

 

Depends on how sneaky you're willing to be. You're thinking right in that you have to be able to feed it. The fact that you plan on keeping RPM down...I'm guessing 5500-6000 max helps a lot.

I'd build a 496, install ported oval port iron heads or some nice aluminum Brodix/AFR with some disguising. The cam choice will depend on heads...but a hyd roller makes a lot of sense and I doubt it would be a single pattern. I'd add some exhaust duration to help the limited exhaust potential. I'd port the heck out of the ex manifolds.

CK out 632C2 here on the Forum....he has a 548" with iron manifolds and a tripower that makes about 700 RWHP and runs high 9's in the qtr. Way past what you're doing....but the point is he's doing all that through manifolds. They have 3" pipes bolted to them and use little 12 point nuts on the studs...but they work!

JIM

 

The 427 will rev faster than a 454, and due to stroke, can rev higher and keep the same piston speed as the 454
How many 100k+ 454 vettes have ever sold .....zero
If the 454 was a better motor, they'd have put it in L88
You can stroke a 454 to 427 but it's still a 454 crank.
You wanna build a Frankenstein or a Marilyn monroe?
And really, The paint job on a vet costs more than the motor so why not build it right?
or are you going to say rattle canning it is just as good too?

"Put the 454 in the pickup and the 427 in the Vette"

 

you can build a 454 for $3,000,,

go find a real 427,,used their $5-10k with vette stampings

and GM used the same block for 69 and 70 vettes

as i read it this isnt a numbers -matching car

 

LOL, in what universe can you build a 454 for 3k?
Show me the math on that?

 

VW microbuses have been selling for multiple hundreds of thousands of dollars, so I guess those air cooled 1.1L 25 hp 4-bangers are even better engines!!!!


Or we can evaluate engines separate from the car and find the 454 is better in every way except, possibly, nostalgia. For street cars piston speed almost never limits RPM. It’s air flow and valve train more often than not.

 

"454 is better in every way except, possibly, nostalgia."

That statement makes me realize you have no clue about what you're talking about.

 

Oh........duh, right. Sorry for momentary stupidity.

 

bbc short from GM is $2200 assembled

a pair of bbc alum heads are $ 700-1200 complete

intake,cam,misc parts are about $900

so im at $3600,,all new,[i could do the same used for $2500]

and if i look around i can find things cheaper

i just bought a 555'' bbc complete for $6,000 [made 700+hp ] with 3-4hrs dyno time,intake to oil pan with 1250 carb,msd ign,flywheel,,[included shipping]

 

I think 4k is about as cheap as you are going build to a BBC ready to drop. 3k, not unless it needs machine work.

I will say this. The 454 is a good engine under 5800rpm but over that, the 427 eats it for breakfast, lunch and dinner

 

Thanks Jim. You are correct about my RPM limits. I also would like a hydraulic roller setup, just because of the break-in issues and longevity, but its not mandatory. Of course, that is more expensive. Glad to hear about the 700 HP on iron manifolds,.....seems I then have nothing to worry about. I plan to run factory size15X8 tires, so.....another limitation that makes this pretty easy for me. I would be happy to say I have 500 pounds of torque,......so, from the little know, this should not be hard to do achieve with my limitations. Just as I wanted with my 77 I care about acceleration, not speed. Obviously, I will be building a mild Big Block. But, its all I need.

 

I thought you meant you could buy a new GM Performance 454 for $2200.......so I checked, but I could not find that anywhere. They are closer to $5000. What am I missing?