Old Cars and New Engines: What's considered enough power?

[That72Kid]

Hey guys, I was wanting some opinions on what to do with my chevelle. As of right now, i'm planning on putting a carbureted LS2 403 stroker in my car. After getting some input from friends/shop builders, I have been told I might not want to go with that engine.

I've made countless threads asking a million question throughout the internet, but i'm just trying to find the right route for my car.

I'm wanting something that I can have fun with, isn't slow, and makes good power without getting 3 miles to the gallon. I'm leaning LS engine because they're lighter, reliable, and I believe you can get more bang for the buck. The problem is, some people believe this engine won't suit my car because there is not that much torque to push a heavy car around. Not to mention I only have a 3 speed with 3.08 gears.

Thoughts?

Here is an old dyno sheet they gave me:

[72BBSwinger]

I dont see a lack of torque at all. That engine puts out more torque than a factory LS6 Chevelle did when new. An OD transmission makes old iron just that much sweeter and yours wouldnt be an exception.

[rustomatic]

Do you require a 10-second car? Do you have the time to build a chassis that an actual 10-second car requires to make use of the required power?

[That72Kid]

Do you require a 10-second car? Do you have the time to build a chassis that an actual 10-second car requires to make use of the required power?

Not necessarily. I've wanted a new engine for the 3 years i've had the car, and that time has come. I think just like most guys, I want to change my car piece by piece.

In all honesty, I join forums to get helpful insight from people who have done this before. I would hate to make a brash decision because I didn't look into something, and then turn around down the road because I could have done something better. I'm just trying to go a little faster, but i'm not sure which route to take.

[Schwartz Performance]

539 lb ft is a lot man.. You'll be spinning the tires in first and second for sure.
Our 65 Tempest has around 500 lb ft and a t56, and it spins first gear with 335 tires.

You'll be fine.. There's nothing wrong with those numbers.

-Dale

[garys 68]

I put a 400hp LS2 in my 68 corvette with plans for 500hp with L92 heads and cam. The stock motor already overpowers the stock tires/suspension.
Unless you're planning on radical tire/suspension changes, that motor will have more than enough power.

[charchri4]

LOL it had no trouble slinging around the 4500 lb GTO it came out of! The only thing I would do different is not run the carb but no matter what that engine will be many times better than what you are pulling out of it.

But to answer your power question this is the way I look at it. With good suspension and brakes a power to weight ratio of 10 lbs per HP is a fantastic car to drive and no question well worth the effort to upgrade.

Take it a few bumps up with something like a ride tech set up with brakes and chassis to go with it and a power to weight ratio of 7 lbs per HP puts you in the top 3% of best cars ever to hit the road. It is simply stunning in every way to drive yet comfortable enough for date nights and reliable enough for long trips.

Bump up to a coil over 4 link set up with big brakes and tires that will hold it and 5 lbs per HP... Well I think you would find driving this car so euphoric that nothing else would matter in life. You never want to do anything but drive it and soon abandon all you love just to spend more time with the car. You will never even care if you have sex again which is why I'm holding back at 5.5 lbs per HP in mine...

So yeah 574 HP in your what 3800 lb? car puts you well into the happy range at 6.6 lbs per hp. That is going to be a great ride!

[69cutlassrkt]

man, they must think your car is really heavy. Kind of a waste to me if you want decent gas mileage and plan on making it carbed. I guess I meant to say it's like an oxymoron.

[chuckd71]

4.8s and 5.3 come in trucks that do work; I can't imagine why a 403 wouldn't be good enough for a car you just plan to mess around in.

[Todd in Vancouver]

My car is 4100lbs and with an LSA it hauls a$$ and gets 22mpg when I'm not standing on it. I've also got a '67 project car that I built a really nice SBC and my only regret is not getting an LS engine. They're easy to upgrade, reliable, get decent mpg and can make more than enough power to haul butt. My only comment is don't do the carb and get fuel injection. If you are stuck on the carb look there are a number of FI units that will take a chrome style open air cleaner so it has the carb look. JMHO.

[fishface]

I am planning a stock ls3 with headers and a tune. Was going to go with a cam but then rode in a friends new Camaro and said why? At half the weight and much more power than my old big block, I am positive it will be more than enough.

[novajess1972]

My 72 Chevelle has a 454 big block with 450hp/500tq, and is a beast! I have a tko600 behind it and it just rips! Trust that you will not see a lack of power for what you think is a heavy car.

[1966longroof]

Those are some Nice Numbers...however, you'll start finding the weak-links in the rest of your drive train when you start to play.

[Kenova]

I'm thinking about a LS3 for my '77 Vega.
Do I need my head examined?

Ken

[Schwartz Performance]

We built a 5.3 LS Vega a few years back.. Nah you're ok in the head... ;)

-Dale

[charchri4]

I am planning a stock ls3 with headers and a tune. Was going to go with a cam but then rode in a friends new Camaro and said why? At half the weight and much more power than my old big block, I am positive it will be more than enough.

If not for the power then for the sound! IMO there is no such thing as too much power just too little traction and too little control.

[CarlC]

Those are some Nice Numbers...however, you'll start finding the weak-links in the rest of your drive train when you start to play.

This, plus your radiator, oiling system/cooler, PS system/cooler, etc.

The engine is just one part of a system that must work together in order to function properly.

[Kenova]

We built a 5.3 LS Vega a few years back.. Nah you're ok in the head... ;)

-Dale

Do you think you could tell my wife?
You are far to modest to admit it, but the Flying Turd was legendary amongst us Vega fans.

Ken

[That72Kid]

Thanks for the feedback guys. As far as supporting mods go, a 4-core radiator and dual fans should keep it cool.

Even if the motor is nice and healthy, won't a 3-speed and 3.08 gears be limiting? What about a gear vendors overdrive and lower gears?

What setup would you guys recommend to make this a well rounded car?

[csouth]

I'd go with EOD personally. The gear vendors are pricey new and good luch finding a used one assuming any 3spd you have can handle that engines power. Theres a Hughes 4L80E for sale in the classifieds the would handle your setup with no problem. That would be my solution....