Top end vs 383 stroker

[UtOBS]

So, im aiming for about 430 crank HP.

Is it possible to hit this without messing with bottom end.

What would AFR top end kit, pistons (aiming for 10:1 compression ratio), a cam, Holley 650 cfm, and long tube headers get me?

Or is it worth the extra 1300$ to 383 stroke it. Seems like I can get a 383 stroker kit on summit for 1300?

Also what is a good clutch that will hold up to ether of these for a 1990 regular cab stepside manual

 

[Drunkcanuk]

I'm gonna assume a TBI 350 here.
No....you may get 400hp with a 200 shot of nitrous, but you will expose the inside of the lower end pretty quickly!
These are not LS motors where a quick cam change gets you close to 400.
I would be weary of trying to achieve that kind of HP goal without beefing up the bottom end.

 

[Schurkey]

So, im aiming for about 430 crank HP.

Look at, and learn from what GM did to create the "ZZ430" performance crate engine. Note that this is still a 350, and the torque curve is not optimal for a pickup truck.

Chevrolets ZZ430 350CID engine, should I duplicate it ? Camshaft? Heads? - Don Terrill’s Speed-Talk

Is it possible to hit this without messing with bottom end.

Probably not, or at least not for long before it pops. What bottom-end are you starting with? Compression ratio?

What would AFR top end kit, pistons (aiming for 10:1 compression ratio), a cam, Holley 650 cfm, and long tube headers get me?

First Guess: You're not going to see 430 HP with a "650 Holley" unless you add-in supercharging or nitrous.

Or is it worth the extra 1300$ to 383 stroke it. Seems like I can get a 383 stroker kit on summit for 1300?

The 383 is really popular due to the availability of cheap Chinese cranks and rods, and usable 5.7L blocks. The added displacement helps with the lower-RPM torque.

It's a damned shame that GM didn't sell more 400s; and doesn't still sell new and decent SBC 400 blocks that weren't the expensive "Bowtie" blocks.

 

[UtOBS]

Look at, and learn from what GM did to create the "ZZ430" performance crate engine. Note that this is still a 350, and the torque curve is not optimal for a pickup truck.

Chevrolets ZZ430 350CID engine, should I duplicate it ? Camshaft? Heads? - Don Terrill’s Speed-Talk

Probably not, or at least not for long before it pops. What bottom-end are you starting with? Compression ratio?


First Guess: You're not going to see 430 HP with a "650 Holley" unless you add-in supercharging or nitrous.


The 383 is really popular due to the availability of cheap Chinese cranks and rods, and usable 5.7L blocks. The added displacement helps with the lower-RPM torque.

It's a damned shame that GM didn't sell more 400s; and doesn't still sell new and decent SBC 400 blocks that weren't the expensive "Bowtie" blocks.

Stock bottom end, the motor is bone stock. I’d be aiming for around 10:1?? More if it will handle it.

 

[Schurkey]

Is this a V-6? Is this a 305? Is this some generic, production-line rebuilt 307 engine that's been pulled out of a '72 Nova?

You don't want to mess with the "bottom end" but then you talk about putting different pistons in it. Pistons are part of the "bottom end", generally press-fit onto the connecting rods. You can't change 'em without pulling the rods apart.

If I wanted 430 horsepower in a pickup truck, I'd be searching for a core 454 to modify. It'd have a better torque curve than a 350, and cost the same or maybe less to build--although any potential saving would be eaten-up with stiffer front springs, and either engine would need a stronger transmission/driveshaft/rear axle.

 

[L31MaxExpress]

Look at, and learn from what GM did to create the "ZZ430" performance crate engine. Note that this is still a 350, and the torque curve is not optimal for a pickup truck.

Chevrolets ZZ430 350CID engine, should I duplicate it ? Camshaft? Heads? - Don Terrill’s Speed-Talk

Probably not, or at least not for long before it pops. What bottom-end are you starting with? Compression ratio?


First Guess: You're not going to see 430 HP with a "650 Holley" unless you add-in supercharging or nitrous.


The 383 is really popular due to the availability of cheap Chinese cranks and rods, and usable 5.7L blocks. The added displacement helps with the lower-RPM torque.

It's a damned shame that GM didn't sell more 400s; and doesn't still sell new and decent SBC 400 blocks that weren't the expensive "Bowtie" blocks.

Might not be an ideal torque curve looking at it on paper, but it is makes more torque everywhere than any 350 GM ever put into a pickup. There is not a single point in that engines RPM curve it would feel down on power to a stock engine, even a L31 350 vortec. The GM 6395 cam might make a shade more low-speed torque up to 2,500 rpm than the cam in that one but would likely push it into detonation in hot weather.

 

[Erik the Awful]

The stock heads won't get a 350 to 430 hp without work, but a 350 with good aftermarket heads would be capable of it. A 383 could do it in a more relaxed, truck-like manner, but it'll still need good heads.

A two-bolt main bottom end is plenty strong for up to 500 hp, so long as you keep the rpm safe. That's the rub - the safe redline on stock rods is about 6000 rpm, and you're going to have trouble making more than 400 hp without spinning the motor faster. If you're towing, 430 hp is going to be putting a lot of strain on the mains. You'll really want a 4-bolt bottom end if this engine is going to tow much.

Why are you considering replacing the pistons? Just for a compression increase? Going from the commonly available .040" gaskets to .016" head gaskets will get you half a point of compression. If your deck is stock height and the pistons are .025" in the hole (stock depth), the .016" head gasket should put your quench height at an optimum .041" with a 9.49:1 compression ratio.

If you replace your pistons with flat-tops, you'll pay $100 or more for the machine shop to recondition the rods and swap the new pistons on. Then you'll want new rod bolts, and that's about $80. For $260 you can get a set of decent floating-pin performance rods with new ARP hardware. Floating pistons don't cost any more than press-on pistons and you can install them yourself in your garage. The downside is that they usually sit a little lower in the hole, so you'll need to take about .010" off the deck, and that will give you a 9.99:1 compression ratio.

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Note that my calculations are just interweb idiocy. Always consult with your machinist or your own measuring tools instead of relying on my math.

 

[RacerM95]

The big issue here is, ask 10 people the same question you will get 9 1/2 different answers (many ideas will over lap) From my experience if you want to go 383 for a truck, start with a "010" 4 bolt main block (for the high nickle content) Go to Scat,Eagle et al and get a forged 400 ci crank, Molnar 5.7 Rods (my last one used Chevy Performance Pink rods) Good set of 202/160 heads, roller rockers, Throttle Body Injection, on an Edelbrock Performer intake, a good distributor, good set of headers, A good cam (last one used a custom grind Comp Hydraulic flat tappet),You are good to go lots of Torque...Or as was mentioned before go 454... Its all up to your abilities and size of your wallet....

 

[L31MaxExpress]

The big issue here is, ask 10 people the same question you will get 9 1/2 different answers (many ideas will over lap) From my experience if you want to go 383 for a truck, start with a "010" 4 bolt main block (for the high nickle content) Go to Scat,Eagle et al and get a forged 400 ci crank, Molnar 5.7 Rods (my last one used Chevy Performance Pink rods) Good set of 202/160 heads, roller rockers, Throttle Body Injection, on an Edelbrock Performer intake, a good distributor, good set of headers, A good cam (last one used a custom grind Comp Hydraulic flat tappet),You are good to go lots of Torque...Or as was mentioned before go 454... Its all up to your abilities and size of your wallet....

I like the 880 blocks and I have built them all. You could not give me a 010 block now. You could pay to buy a Dart SHP block cheaper than the machine work needed to fix everything wrong with those junk 70s blocks. Just my $0.02.

 

[RacerM95]

@L31MaxExpress Like I said, ask 10 people the same question you will get 9 1/2 different answers.
I just happen to like the 010 its a tough block