Sixpack on a 318 engine ?

[Dale Davies]

A 327 2 barrel was rated at 235 horse. Huh! My 273-4 barrel was rated the same. According to the information below, the 318 did pretty good for itself against Chevy's 327.

"The last iteration of the 327 appeared in 1969 with a two-barrel carburetor and a 9-to-1 compression ratio that produced 235 horsepower and 325 foot pounds of torque."

USA specifications	273 V8	318 V8 (LA)	340 V8
Gross horsepower, 1968 (1962 for 318-A)	190 @ 4400	230 @ 4400	275 @ 5000
Torque, lbs.-ft. , 1968	260 @ 2000	340 @ 2400	340 @ 3200
Compression ratio, 1968	9.0 to 1	9.2 to 1	10.5 to 1
Bore, inches	3.63	3.91	4.04
Stroke, inches	3.312	3.312	3.312
Carburetor type (1968-73)	2-bbl.	2-bbl.	4-bbl.
Fuel	Regular	Regular	Premium

Cam, compression, and intake. 318's, like the 2V 302 and 305 suffered from an emissions cam, low intake valve lift. They also had low compression. Install quench heads with zero deck pistons to get compression and efficient combustion, a cam in the 220°@ 0.050" lift and 0.500 valve lift, and a 4V intake and carburetor to wake them up.

 

[toolmanmike]

Cam, compression, and intake. 328, like the 2V 302 and 305 suffered from an emissions cam, low intake valve lift. They also had low compression. Install quench heads with zero deck pistons to get compression and efficient combustion, a cam in the 220°@ 0.050" lift and 0.500 valve lift, and a 4V intake and carburetor to wake them up.

Yep, basic hot rodding. Ford and Chevy did it. Mopar kept the Teen as a basic workhorse. Well, until nothing much else was left and they put them in a cop car with a 4 barrel and some 360 heads.

 

[Dale Davies]

I believe Magnums had 8mm valves. I do like the idea of beehive springs.

5/16" or 8mm. The 8mm are about 0.002" bigger stem diameter. Pretty close to the Magnum head diameter, but I think 0.020" bigger diameter, unless you get the 2.0" intake valves. Cost is a big advantage. Compared to a 318 LA intake valve, the LS valves are about 25 to 30 gm lighter. Then you toss in the beehive retainers that also save weight. The beehive spring is also lighter on the top end that moves, and has excellent resistance to resonance issues. You can generally pick up 500 RPM before valve float.

 

[toolmanmike]

5/16" or 8mm. The 8mm are about 0.002" bigger stem diameter. Pretty close to the Magnum head diameter, but I think 0.020" bigger diameter, unless you get the 2.0" intake valves. Cost is a big advantage. Compared to a 318 LA intake valve, the LS valves are about 25 to 30 gm lighter. Then you toss in the beehive retainers that also save weight. The beehive spring is also lighter on the top end that moves, and has excellent resistance to resonance issues. You can generally pick up 500 RPM before valve float.

I have seen high speed videos. They do work and I could use the clearance.

 

[Icetech]

If I remember right, the 365 solid lifter 2.02 head motor had 11 or 11 1/4 to one.
Put a modern solid cam in, some econo w2s on it, 10 to 1 pistons, airgap intake with a 750 dp, headers in/on your 318, and hang on. 400+hp to thrash 327s (and 350s) with.
Edit: the solid cam 327s redlined at 6500, would go past that. I spun my hydro cammed 350 (370hp version) to 7500, cause it would.
It would have been quite a bit faster if I had shifted at 6500. DOH!

i wish i could spin **** that high.. i tend to chicken out around 5500.. i worry too much bout **** blowin up

 

[Newbomb Turk]

If you look at these 3 Chev engine built pretty much to the same spec except the 350 has a hydraulic cam, They are making about 355 hp but at different rpms, 302 @ 6600 rpms, 327 @ 6100 rpms and 350 @ 5400 rpms, first thing most are gonna say is yes they make same hp but look at the torque difference, but you shouldn't be gearing these 3 engines similar obviously the 302 is gonna need the deepest set of gears 327 a little less and 350 less than that. So at any given mph the 327 and 302 will/should be turning a higher rpm putting it in it's powerband and should be putting similar hp and torque to the ground.

For most obviously the 350 would be considered the most streetable followed by the 327 then 302, which is a personal choice but for full throttle performance if geared and stalled right should have similar capability.

View attachment 1716278843

That’s because torque doesn’t really matter.

I’ll take a semi long pause for the requisite flaming, bitching, moaning, whining, gnashing of teeth and all that.











Done correctly the engine with more HORSEPOWER wins every time.

Of course there are geometric and financial considerations and limits.

That’s why if you have a 300 inch engine trying to run the same as a 500 inch engine that is at the limits of rpm you can’t win.

 

[RustyRatRod]

All the center carbs are "350 cfm" . Actually, if rated as if they were four barrels, total flow is less than 1000 cfm, in spite of the "1350" b.s.
I believe the corvette 427 tripower carbs are smaller than the Mopar version.
But, thank the vette guys.... if there weren't corvette tripowers, there would be no sixpacks.

Ehhh....the 406 Fords were well before that.

 

[rumblefish360]

okay i stumpled aver this Six Pack and the price was right. I know a 340s would be cool but the only thing i have is a 318 which i plan to rebuild the cheap way. Hone it, , new rings and so on, a basic re reing job.

What you guys think, is it a bad idea to use the sixpack in this ? And if the answer is yes , what cam should i use?
Car will be a 66 Barracuda with a 904 automatic not sure about the rear end ratio. Converter stock.

Yes! Do it. Send it done. Absolutely go for it.

Cam size determines RPM range that works in concert with your converter, gear ratio, tire size and cars weight to achieve the intended goal.

 

[Dale Davies]

i wish i could spin **** that high.. i tend to chicken out around 5500.. i worry too much bout **** blowin up

If you run an Airgap manifold, there is minimal heating of the air/fuel charge. These benefit greatly with annular discharge boosters. The Edelbrock AVS2 carbs have annular primary boosters. Some Holley or Holley copy carbs have annular boosters, mainly Dominator based.

 

[Icetech]

I love a good Annular Discharge...

 

[Newbomb Turk]

If you run an Airgap manifold, there is minimal heating of the air/fuel charge. These benefit greatly with annular discharge boosters. The Edelbrock AVS2 carbs have annular primary boosters. Some Holley or Holley copy carbs have annular boosters, mainly Dominator based.

Welp, the answers are in the post if you pay attention.

 

[Newbomb Turk]

I love a good Annular Discharge...

Ok, no one wants to know THAT lol.

For that you get the

And

And

You know why you earned the Red X.

You got the red car because it’s the only other red picture of anything I had.

And my Dixie Dingo who really has no concerns for your discharges of anything.

You scored the RED trifecta.

 

[33IMP]

Ehhh....the 406 Fords were well before that.

Agree, I forgot about the tripower ford's. But they hadn't made many 406 Ford carbs, and the vette carbs were only two years into their run, and holley was making assembly line carbs currently. Supplying carbs to Mopar was a cakewalk.

 

[33IMP]

i wish i could spin **** that high.. i tend to chicken out around 5500.. i worry too much bout **** blowin up

Frankly, I was shocked that it would spin that high. It had a sig hydraulic cam, with only 225 at .050. and a stock nothing remotely special valve train. It took a looong time to get there in third (4sp, 4.56).
I think it could have been at least a half second quicker, shifted at 6500. I'm betting that 7000 was WAY past the hp peak!
I did learn my lesson though. I experiment with shift points all the time, shifting as soon as I can, and still run decent .
The small block roller motor in this was shifted at 6000.

 

[33IMP]

That’s because torque doesn’t really matter.

I’ll take a semi long pause for the requisite flaming, bitching, moaning, whining, gnashing of teeth and all that.











Done correctly the engine with more HORSEPOWER wins every time.

Of course there are geometric and financial considerations and limits.


That’s why if you have a 300 inch engine trying to run the same as a 500 inch engine that is at the limits of rpm you can’t win.

Okay what about two different motors that make the same power? Wouldn't the one with more torque, a LOT more torque, be quicker?
Enginemmasters compared a 372 cu in, small chevy with 500 hp to a 500hp 454.
I'd bet my house on the 454 being quicker at the same weight,...... with more than 120 more ft/lbs of torque.

 

[Icetech]

Ok, no one wants to know THAT lol.

For that you get theView attachment 1716278985

AndView attachment 1716278984

And

View attachment 1716278986

You know why you earned the Red X.

You got the red car because it’s the only other red picture of anything I had.

And my Dixie Dingo who really has no concerns for your discharges of anything.

You scored the RED trifecta.

made me laugh and that dog rules... zero fucks given

 

[Newbomb Turk]

Okay what about two different motors that make the same power? Wouldn't the one with more torque, a LOT more torque, be quicker?
Enginemmasters compared a 372 cu in, small chevy with 500 hp to a 500hp 454.
I'd bet my house on the 454 being quicker at the same weight,...... with more than 120 more ft/lbs of torque.

You'd have the RPM of each engine to know.

In the example above the 302 has more RPM and can use more gear.

Just line rock crushes scissors, gears crush torque.

 

[harvenator]

318 wasn't "made" to turn rpms because it didn't get the "good parts" like a 340. I've seen 318's turn 7200 rpms for years with stock bottom end. 340's havent' been made for over 50 years, folks are working with what they have or what they can get. It's ridiculous that we can't get past that 340's are no longer in the junkyards for 75 bucks and 318's swap cams and heads and pistons just like ANY other engine being built, including the 340's. Yes, I'd rather have the 340, but no, I'm not paying the "340" tax.

New 340 blocks and crate engines are available aftermarket. Don't know of they're worth it but....

 

[33IMP]

You'd have the RPM of each engine to know.

In the example above the 302 has more RPM and can use more gear.

Just line rock crushes scissors, gears crush torque.

Maybe. IF (big if) you are willing to USE the gears. (Much easier nowadays than it used to be, now that 8 speed automatics with two or three overdrives are available!).
But I'd rather have great torque with reasonable gears that would give the same power and performance as a car with crazy gearing and rpm. Better street manners better gas mileage, better engine life, same performance? No-brainer.
( and for reference, the big block/small block test referenced, big block hp peaked at 6000, carried to 6200 pretty well, the small block peaked at 6600, and fell off at 68/6900.
They figured to run 115, the big block could use 3.73s, the small block would need 4.88s.
I'll take the torque and 3.73s every time.

 

[273]

Okay what about two different motors that make the same power? Wouldn't the one with more torque, a LOT more torque, be quicker?
Enginemmasters compared a 372 cu in, small chevy with 500 hp to a 500hp 454.
I'd bet my house on the 454 being quicker at the same weight,...... with more than 120 more ft/lbs of torque.

If you gear them both for the best 1/4 mile time the 372 is generally gonna need deeper gears, if you calculate the torque to the ground they should be very close, so at the tire they would have similar hp and torque at similar speeds.

 

[Newbomb Turk]

Maybe.
But I'd rather have great torque with reasonable gears that would give the same power and performance as a car with crazy gearing and rpm. Better street manners better gas mileage, better engine life, same performance? No-brainer.
( and for reference, the big block/small block test referenced, big block hp peaked at 6000, carried to 6200 pretty well, the small block peaked at 6600, and fell off at 68/6900.
They figured to run 115, the big block could use 3.73s, the small block would need 4.88s.
I'll take the torque and 3.73s every time.

I get that’s what you prefer, but it’s not the quickest and fastest.

And obviously there is a limit to how much gear I can tolerate on the street.

My limit is a 4.56 gear and a 26 inch tire and a 4.88 and a 28 inch tall tire

Maybe. IF (big if) you are willing to USE the gears. (Much easier nowadays than it used to be, now that 8 speed automatics with two or three overdrives are available!).
But I'd rather have great torque with reasonable gears that would give the same power and performance as a car with crazy gearing and rpm. Better street manners better gas mileage, better engine life, same performance? No-brainer.
( and for reference, the big block/small block test referenced, big block hp peaked at 6000, carried to 6200 pretty well, the small block peaked at 6600, and fell off at 68/6900.
They figured to run 115, the big block could use 3.73s, the small block would need 4.88s.
I'll take the torque and 3.73s every time.

And I'd take the other because gearing doesn't bother me. I should say for the street.

Race car gearing starts at 5.13 and goes up for there.

 

[33IMP]

My Tina ran the same in the eighth, and was faster in the quarter, when I removed the 5.14s, and put in 4.57s. (Quit pulling at about 1100 feet).
But I will freely admit, the converter swap (after the gear swap) made a lot more difference.

 

[33IMP]

Boy, did I veer off topic, or what? My apologies to the o.p.


If you've got it, flaunt it. Throw the Sixpack on!

 

[Newbomb Turk]

Maybe.
But I'd rather have great torque with reasonable gears that would give the same power and performance as a car with crazy gearing and rpm. Better street manners better gas mileage, better engine life, same performance? No-brainer.
( and for reference, the big block/small block test referenced, big block hp peaked at 6000, carried to 6200 pretty well, the small block peaked at 6600, and fell off at 68/6900.
They figured to run 115, the big block could use 3.73s, the small block would need 4.88s.
I'll take the torque and 3.73s every time.

I get that’s what you prefer, but it’s not the quickest and fastest.

And obviously there is a limit to how much gear I can tolerate on the street.

My limit is a 4.56 gear and a 26 inch tire and a 4.88 and a 28 inch tall tire.

 

[Icetech]

I have never had a converter other than stock til this car, kinda excited to see how it feels..