mygasser
Well-Known Member
now you're repeating what you were told here many times in your 318 threads except you argued about it every time then based on what you'd read or what your mates told you.
273 or NOT 273?
- Thread starter 67_Slimer
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Dan the man
Well-Known Member
I really need to get a better handle on this, sometimes I wind up going over things that I shouldn't or that's not necessary. My bad.
junkyardhero
Well-Known Member
how do you not get that it's not about building a for power in an overlooked motor?
it's about building a rip snorting hi-rev 273 because.people.don't.do.it.
to your line of thinking: if the 318 is better, then why not a 340, or a 360 that would be even more money ahead.
it was never about building anything but the 273.
forest for the counting the trees before they hatch, daniel.
Dan the man
Well-Known Member
I've given it more thought which is what I should've done to begin with. I, too, like the under dogs like the chevy 283/307, ford's 289 and the 318's. I guess the only reason why I was never a fan of the 273's was because of the lack of performance pistons and it's small bore
4eighteener
Well-Known Member
There is definitely an overwhelming interest on this site for a high performance 273 build.
Maybe like toolmanmike says, someone will do it, document it, and dyno it.
With this interest, a go fund me is in order!
Maybe like toolmanmike says, someone will do it, document it, and dyno it.
With this interest, a go fund me is in order!
273/318 threads seem to generally get more views and replies.
4eighteener
Well-Known Member
Dan the man
Well-Known Member
junkyardhero
Well-Known Member
i think it's also the ubiquitous nature of particularly, the 318. everybody has one.
stack that with the "devil you know" mentality of: i have a 318 2bbl that runs good, what can i do to make it a little better and not spend 5K? and it quickly becomes apparent why there's so much draw toward the mighty 318.
Exactly. It's a solid platform to build on.
mygasser
Well-Known Member
agreed, the 318 haters bang on about the tiny bore but it's only 90 thou less than what many believe to be the 'majic' 4" bore like the 360. it's really not that much, less once overbored. not many slate the chevy ls for it's bore size after all. at the end of the day it's still a 5.2 litre v8 and should be treated as such.
neil.
I also think everyone basically knows/agrees what do to a 340/360 etc.. With 273/318 there's a lot less agreement how to proceed, half the argument is if you should or shouldn't in the first place nevermind what to do if you should.
318's are easy really, just like with any build. 4 barrel, dual exhaust, and advance curve first especially if you are on a low budget. Those 3 can be done in any order or all at once. May be Headers next. They will help but not make a huge difference until you go to the next step which I would recommend you do all at once. Cam, converter, and gears. You may need them all. Most 318's have around 9/1 compression so pistons aren't at the front of that list unless you are building one and need new slugs anyway. Aluminum heads may help anytime along the way but more after the new cam. You can add roller rockers but that all depends on the cam and they won't bump you to the next level on the dyno charts. Lots of things you can do and add. Some make power and some don't make a lot of difference. Just use a little common sense. And so you don't have to buy better parts at the next step, Choose the major components carefully. Like, a LD4B and a 600 cfm carb will work well on a stocker but after the big cam, aluminum heads, 4000 stall converter, and 4.10's, you might need something bigger and better.
This will decimate all. lol
655 CID or 2 times 327.5 CID. 
Or 2.4 x 273
You do not understand. A 318 "all" things being the same, will run very similar to a 273 but at a lower rpm. A 273 was a high performance engine with a forged crankshaft so no matter what you do to a 318, you have to do a lot to catch up. But not much of a price difference when rebuilding an engine, pistons, cam, etc. I also include 340/360 heads, carb, intake, distributor, and exhaust. You don't have to do anything to a Commando/Charger 273, it is all there, maybe a slightly larger cam.
You have no clue. You can get anything you want for a 273, because they were a performance engine and still being raced in class racing. "Small" bore has little to hinder the performance to the level most people run. Run what you have, any Mopar engine can run very well if you know what level you want and build accordingly. Slant 6 to Hemi, they all have + and -.
Reality on the 273 vs 318, means it seems this is where the thread has gone.
- very few 273's were commando's with the go fast parts. Most are 2bbl versions.
- Forged crank is actually a slower crank because it's heavier. It's only worth it's weight if serious HP or NOS/Boost is being used in the application. Many cast cranks in 9 and 10 second cars.
- Anyone that's ever driven "up to snuff" 273 2bbl vs 318 2bbl in the same weight of car will know in a heartbeat the 318 has more bottom end torque and power up top. And it's not really even close. Owned both, as well as my Dad's cars as well.
- Both can be made to rev and go fast. Hands down, same stroke/block, the bigger bore will have the advantage. Always does and always will.
Remember, the 318 2 barrel is close to or better than a 273-4 barrel and at lower rpm's. Who wouldn't want 80 lb/ft more torque at 2400 rpm where most of us spend the majority of our time.
273-4 235 hp@5200 rpm 260 lb/ft @4000 rpm
318-2 230 hp@4400 rpm 340 lb/ft @2400 rpm
273-4 235 hp@5200 rpm 260 lb/ft @4000 rpm
318-2 230 hp@4400 rpm 340 lb/ft @2400 rpm
Not really talking about 2 barrel engines. I'm never going to build a 2 barrel anything for myself. What a limit on power. We started talking about a 12 second 273. Dan the Man introduced the 318 as he jumped into the end of a thread without reading the rest. As raw material, I personally prefer a 273 over a 318. I kept 273's and 340 small blocks. I have built plenty of performance 273's, 318's, 340's and 360's over the years. 273's and 340's are about zero deck hight. 64 to 67 273 heads have closed chambers. The same year 273's have a forged crank and bushed rods, not a problem for me, although I see no problem with a cast 318 cranks either, although I doubt any performance gain. Having built a 1.88 intake J headed 273, 318s, and low compression 340's with the same heads, cam, and induction, I have not seen much difference from a larger bore, all things being equal. But I'm not a low rpm torque kind of guy. Nor do I care about drag racing myself. The 273 works perfectly in my 66 Formula S for the limitations I place on my own cars.
I'm not telling anyone what to like, or what their personal preference should be. The hobby is all about doing it "your way". None the less, everything I posted in post 219 is true.
Good thread with lots a different opinions!
My mate has just bought a 273ci 65 Coronet, the engine runs but needs a rebuild.
Firstly my thoughts were ''why bother'' put a 318 in there and save time and money.
Then he says '' 318-LA not available in 65 '' but who actually cares?
I wasn't talking 318-LA I was talking 318-POLY!
He says '' they is more expensive to rebuild than a 273ci '' oops...
So its a 273 versus Poly 318 '' (too expensive) scenario for him.
If its an 65 A-Body then its a 273 every time or don't bother.
My mate has just bought a 273ci 65 Coronet, the engine runs but needs a rebuild.
Firstly my thoughts were ''why bother'' put a 318 in there and save time and money.
Then he says '' 318-LA not available in 65 '' but who actually cares?
I wasn't talking 318-LA I was talking 318-POLY!
He says '' they is more expensive to rebuild than a 273ci '' oops...
So its a 273 versus Poly 318 '' (too expensive) scenario for him.
If its an 65 A-Body then its a 273 every time or don't bother.
That poly had some upsides and potential. A good engine as well. I'd have liked to seen a true performance version (not just a 4bbl) of it in the late 60's before it went away.
Post 219 almost true for forged cranks.
The 318 forged crank was weighted for 318 pistons.
The 273 forged crank was also weighted for 318 pistons.
Whats the difference here?
Monster sized 273 wrist pins to compensate for the imbalance.
The 318 forged crank was weighted for 318 pistons.
The 273 forged crank was also weighted for 318 pistons.
Whats the difference here?
Monster sized 273 wrist pins to compensate for the imbalance.
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