tfjettech
New Member
Just picked up a 66 Cuda with a 273 2bbl, auto trans. Thinking about customizing instead of restore to original. Any advise on a larger engine, manual trans, and upgraded suspension would be much appreciated.
318, 340, or 360?
- Thread starter tfjettech
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Welcome, Nice car, and Good luck. As far as the engine, all you listed would be an upgrade as far as power/torque. But, I ask "why the upgrade"? Many upgrade for power/torque, but some upgrade so they can get hardened seats and a roller cam and not for the power reason.
Anyways, keep us posted
Anyways, keep us posted
dano
Evil Handy Man
Looks nice as it is. 273 are good engines too, don't underestimate them. Being an auto car and you want manual I'd jump to a modern 5 or 6 speed. Other than the cost it would be about the same amount of work over putting the hump in for the shiftier. Headers are going to be your limiting factor for power.
doogievlg
Well-Known Member
I would rebuild the current engine but if you did decide to go with a bigger engine then I would use a 360 magnum or LA just because they are easier to find than a 340.
stroked340
Well-Known Member
360
none of the above, Hellcat crate engine, TR6060, Gerst front and rear tubular suspension....
GTXperience
Orig Stealth Mod
What do you plan on doing with the 66? How do you plan on driving it? Customizing to me may mean something very different than what it may mean to you.
Depends on your end goal and your budget?
Frank Mopar
Well-Known Member
340 first. 360 second. If your going to spend money, spend a few more and you won't regret it
ir3333
Well-Known Member
definitely improve your suspension and convert your brakes to disc if not already disc.Engine choice would be determined by power level your after and budget... a 273 warmed up a bit with a 14 inch tire and 3.23 gears can be quite quick in a small 'cuda.These changes will make it comfortable and fun to drive.Go for big power if you are going to race it.
Basically the bigger the engine the less gear and stall and better idle for a certain hp.
Also depends if your using just the block or block/crank or block/crank/heads.
If you just using block engines will be within 20 cid or so. Not the biggest deal.
Block/crank all 3 same power potential but 318 over 360 will need more gear stall and have a ruffer idle for the hp level.
If using stock heads will limit hp to
273/318 = 300hp ish
340/360 1.88 =375hp ish
2.02 and magnum = 400hp ish
Porting and or aftermarket sky is the limit
Saying all that 360/5.9 is probably your best starting point even if you wanted super mild.
Stock magnum with manifolds and 4bbl makes about 300 gross hp.
Also depends if your using just the block or block/crank or block/crank/heads.
If you just using block engines will be within 20 cid or so. Not the biggest deal.
Block/crank all 3 same power potential but 318 over 360 will need more gear stall and have a ruffer idle for the hp level.
If using stock heads will limit hp to
273/318 = 300hp ish
340/360 1.88 =375hp ish
2.02 and magnum = 400hp ish
Porting and or aftermarket sky is the limit
Saying all that 360/5.9 is probably your best starting point even if you wanted super mild.
Stock magnum with manifolds and 4bbl makes about 300 gross hp.
Problem Building a 273 is cost and rpm.
For near stock rpm ain't gonna be a big deal but to build something similar to a 380hp magnum create engine which you could do.
Notch the block add 1.94 valve magnum heads similar cam intake and exhaust and should make similar power. But a 360 will do it at 5400 peak rpm and need a 3000 stall and 3.55-4.30 gears. 273 built the same needs another 1000-1500 to reach the same power plus 4000-4500 stall and 4.88-5.13 Plus gear. And my idle is pretty ruff.
Even equal to the 300 hp magnum would only be 1000 rpm lower.
For near stock rpm ain't gonna be a big deal but to build something similar to a 380hp magnum create engine which you could do.
Notch the block add 1.94 valve magnum heads similar cam intake and exhaust and should make similar power. But a 360 will do it at 5400 peak rpm and need a 3000 stall and 3.55-4.30 gears. 273 built the same needs another 1000-1500 to reach the same power plus 4000-4500 stall and 4.88-5.13 Plus gear. And my idle is pretty ruff.
Even equal to the 300 hp magnum would only be 1000 rpm lower.
moper
Well-Known Member
We need to know budget and expectations.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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The early As don't really NEED a 360, to be even moderately nasty.
But like 273 said, the 360 will allow you to do more with less.
You don't NEED a big cam, so also don't need a high stall . Because the 360 can make so much low-rpm torque, You get to run a sane 3.23 gear, and a 904.You don't NEED hi-flo heads, or a Big intake or a big carb, etc
Now you can put all those things into your combo, but you will then have to spend a bazillion bucks on the chassis to make it hook. .
I'm with 273
If you have no engine to start with you can't go wrong with mild Magnum
And an A-904 with a 2.45 low. This will get you about 6150@60mph in first,3630 in second and 2500 in direct. Perfect for 3 targets; Zero to 60,kickdown to pass, and a real nice cruiser gear.
Additionally you get 32mph = 1950 in second,3300 at kickdown.
If that interests you; then just build the 360 Magnum to pull hard at 3300 up, to pull to about 5800, and to make mileage at 2500. Easy-peasy. A fast rateof lift roller of about 262 advertised will git it done, with perhaps 226@.050. With one more gear you could pull some impressive mpgs outtof that combo, and be driving cross-country with not enough fuel stops to satisfy your aching bladder.
;
But if you're a stickman, and not interested in cruise economy, well then;just slam some 3.55s in there, with a 3.09 low trans.. These will get you a fabulous starter gear of 10.97 and 65=5500 at the top of second, with a cruise rpm of 65=2870
At 32 mph, the rpms will be 4360-2690-1976-1411; not exactly stealthy, unless you can backshift from third to first; Ka Blaam!!
But like 273 said, the 360 will allow you to do more with less.
You don't NEED a big cam, so also don't need a high stall . Because the 360 can make so much low-rpm torque, You get to run a sane 3.23 gear, and a 904.You don't NEED hi-flo heads, or a Big intake or a big carb, etc
Now you can put all those things into your combo, but you will then have to spend a bazillion bucks on the chassis to make it hook. .
I'm with 273
If you have no engine to start with you can't go wrong with mild Magnum
And an A-904 with a 2.45 low. This will get you about 6150@60mph in first,3630 in second and 2500 in direct. Perfect for 3 targets; Zero to 60,kickdown to pass, and a real nice cruiser gear.
Additionally you get 32mph = 1950 in second,3300 at kickdown.
If that interests you; then just build the 360 Magnum to pull hard at 3300 up, to pull to about 5800, and to make mileage at 2500. Easy-peasy. A fast rateof lift roller of about 262 advertised will git it done, with perhaps 226@.050. With one more gear you could pull some impressive mpgs outtof that combo, and be driving cross-country with not enough fuel stops to satisfy your aching bladder.
;
But if you're a stickman, and not interested in cruise economy, well then;just slam some 3.55s in there, with a 3.09 low trans.. These will get you a fabulous starter gear of 10.97 and 65=5500 at the top of second, with a cruise rpm of 65=2870
At 32 mph, the rpms will be 4360-2690-1976-1411; not exactly stealthy, unless you can backshift from third to first; Ka Blaam!!
If "I" were to do it then it would be a 360/A833 combo.
Aftermarket anti roll bars, frame connectors, HD rear springs QA1 shocks & wide tires.
Simple, mild, noticeable improvements.
Aftermarket anti roll bars, frame connectors, HD rear springs QA1 shocks & wide tires.
Simple, mild, noticeable improvements.
If my car didn't come with a 380hp create engine which is a stock magnum long block with 288/292 cam and M1 single plain.
I would of done a magnum with probably 265/275 ish cam and airgap. Two things that would of made this engine subjectivity more streetable. Also would of port the heads to makeup for the smaller cam and probably end up with similar hp as I have but more of a driver which is what I wanted.
And with your engine even if you didn't port the heads you'd probably end up with the advertised 380 hp since that they dyno more like 410-420. And the 300 hp create with stock cam dyno 320hp so you should pickup 40 hp And with little loss to bottom end maybe even a modest gain.
As for my engine I plan to stick with the cam and add Rhoads lifter to get best of both worlds and port the heads. Also add 1.7 roller rockers which was suggested to me get even more top end. To me you should try to build the longest powerband you can but without moving it too far from idle. And if I can get that to hook up add an airgap if not stick with the single plain.
That's the beauty of these engines doesn't take a lot to get something decent even stock with manifolds they make 300hp gross. Like AJ@ said don't need much with an early A to have fun could even start with a 5.2 magnum similar potential but wouldn't recommend basically cause a 318 needs 0.5:1 more gear ratio to equal a similar built 360 and it's hard enough to get people to run more than a 3.55 gear.
I would of done a magnum with probably 265/275 ish cam and airgap. Two things that would of made this engine subjectivity more streetable. Also would of port the heads to makeup for the smaller cam and probably end up with similar hp as I have but more of a driver which is what I wanted.
And with your engine even if you didn't port the heads you'd probably end up with the advertised 380 hp since that they dyno more like 410-420. And the 300 hp create with stock cam dyno 320hp so you should pickup 40 hp And with little loss to bottom end maybe even a modest gain.
As for my engine I plan to stick with the cam and add Rhoads lifter to get best of both worlds and port the heads. Also add 1.7 roller rockers which was suggested to me get even more top end. To me you should try to build the longest powerband you can but without moving it too far from idle. And if I can get that to hook up add an airgap if not stick with the single plain.
That's the beauty of these engines doesn't take a lot to get something decent even stock with manifolds they make 300hp gross. Like AJ@ said don't need much with an early A to have fun could even start with a 5.2 magnum similar potential but wouldn't recommend basically cause a 318 needs 0.5:1 more gear ratio to equal a similar built 360 and it's hard enough to get people to run more than a 3.55 gear.
dibbons
Well-Known Member
What's wrong with a bad *** 273?
ScampMike
Despicable Damn Yankee
Very nice looking car - you do realize that once you start changing things - - the proverbial "can of worms" opens and it can get out of hand VERY quickly. With that said, it really depends on your goals for the car - reliable daily driver (318), street brawler (340), weekend street/strip thumper (360) or all out race car (built 360)? (just staying with the engine options you have specified)-- how deep are your pockets?? are you ok with the car being "out of commission" for just a weekend or two, a month or two, or for 1/2 a year while it is being transformed?
abodyjoe
Well-Known Member
depends on what you want.. for me i i had to stay small block, i'd go 360 screw the 318 or 340. i'f go 73-up large bolt pattern disc brakes and 8 3/4 rear end converted to big bolt and big brakes, 1+" torsion bars and eaton rear springs and good shocks to start.. 4 spped? can go regular 833. can do a 833 OD, a passon 833OD (not his new 5 speed)..
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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Nobody going to touch this? OK I'll go first; what's the thread title again?
I tell you what tho, I bet I can get mid 20s to near 30 mpg out of one of those 273s,Without an overdrive.........Into the 30s with a 5-speed stick, and it will still fry the OEM sized tires in first gear, in that Barracuda.Maybe even whatever fits in those stock rear tubs.
Ima thinking the Aisin AX15. Somebody here is gearing up to make SBM adapters. This is an ideal candidate for a 273/318. I think the ratios are 3.83-2.33-1.44-1.00-.79od. You can run that with a 2.76 equipped 7.25 with an LSD and let her buck.
The starter gear would be 10.57, and the cruiser;2.18, would get you 1868@65mph.
Second would get you; 32@2700, and 60@5100
Third gear would get you about 95@5000.
So those numbers will work best with; a lot of Dcr, TightQ, decent heads, and a torquey cam.
I'd pump the compression up so high that it would require anti-det.injection. Ima thinking close to 11/1Scr with a 262/270/106 cam. That'd be close. At 11.0Scr that gets a Dcr of 9.14@189psi and a VP of 129. The compression distance is 122* and power extraction is 120*. Overlap is a bit generous for the combo at 54*, so headers will pump up the power. Yeah with iron heads it will detonate. But there's ways around that.
Between the 129VP and the 10.57 starter, this is a tire-frier.
Between the 9.14 Dcr and the 2.18 final drive, I can totally see fabulous fuel mileage.
The other gears are bang-on for having street fun. And guess what; more performance is just a rear gear swap away. But 3.55s are about the max to run, still tho,right in the ballpark. Lessee, 3.55 x .79od is 3.195 final drive, and 65 is still just 2740.
If I was stuck with a 273, or was trying to prove a point, I think this is about what I would do.
Oh one more thing; Wait til you hear that hi-comp 273 screaming for mercy pulling two gears all the way to 60/65. Ima thinking Purple Hornys and 2.25s.
Then stuff it into OD and and cruise in quiet comfort at 1868rpm.
If you need a frame of reference;
a 360 would need an Scr of just 8.8 to achieve a Dcr of 7.38@144psi and a VP of 127; with that very same cam. The 273 will need about 440cfm to satisfy the equation,and will need premium gas with an anti-detonant, while the 360 will need a 520carb, and burn shunk-pee.
That's why I say "stuck with a 273".
If a turbo is on the table, well then, with a rearrangement of parts,she'd start to be bad-azz. Hyup, I could see that making 400 pretty quick. But say goodbye to the 5-speed.And along with that the great hi-way mileage. But you could keep the 2.76s,lol. And I would go automatic.
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Frank Mopar
Well-Known Member
No such thing as a bad *** 273 that I know of
The problem with building smaller like the 273 is ultimately gearing. Obviously the bore is a problem at a certain hp level only get so much air flow but I'd imagine some one crafty could get 500 hp +. Then next is rpm 400 hp depending on the build would be high 6000 to low 7000's, 500 hp would be over 8000 rpm.
And even if that was ok with you back to the gearing problem. A 400hp 360 probably needs 4.10-4.30 gears to get the most out of it but most would run 3.55 and few 3.73-3.91. A similar 273 is gonna need about 1 ratio deeper so minimum 4.56. Even a 3.55 geared 400hp 440 would be better than 360 cause the 3.55 would suit the 440 better.
If your willing to gear it run it, if not build bigger.
And even if that was ok with you back to the gearing problem. A 400hp 360 probably needs 4.10-4.30 gears to get the most out of it but most would run 3.55 and few 3.73-3.91. A similar 273 is gonna need about 1 ratio deeper so minimum 4.56. Even a 3.55 geared 400hp 440 would be better than 360 cause the 3.55 would suit the 440 better.
If your willing to gear it run it, if not build bigger.
doogievlg
Well-Known Member
The forum member has not posted a single response to this thread.
Dartswinger70
Well-Known Member
The goals for my car are to do a smoky burnout all the way down the street.........that being said, I have a 340, but if it can be done with a 273, I say go for it.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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Hold on boys................... What would a Miatta weigh with a 273- M/T? Say 2400 pounds. A plane Jane 273Commando would be bad-azz in that wouldn't it? That's about 10 pounds per Hp, and that 273 would not be "hi-strung". That would be no worse than a 340 2-gen Barracuda.And about the same as a 3-gen E-360. Everybody always brags on their 340 E's; good grief they'd be slooooow in comparison to that Miatta,lol.
Hyup; a 273 5gear Miatta; that would be badazz.
Lessee how can we get an early A down to 2400? That shouldn't take much,lol.
I think the backseat alone is 65#, 2 bumpers at 30#, the heater at 35# Empty the trunk,aluminum wheels, radio delete, manual everything shoot the P/S alone is about 300 kgs IIRC.(lol). Yeah 2400 should be doable. Now yer in badazz territory.Well OK yer just tickling it. Now pump it up to 300hp and make it stick. Then take a break,yer done. 2400/300=8 #/hp; that's badazz. Now you could be in the 11s. Lessee 300/273=1.1HP/cid, totally doable.
Course a 360 only needs .83hp /cid. That's 2bbl territory right there. And the 360 will be about as docile as a 10 year old cow. And I guess you could put the earlyA back together and run it at 2800,and pump up the 360 to 350 hp or .97 hp/cid . Still a pretty tame lump.
Tame lumps are way more fun than trying to stay on the pipe all the time. I mean just try and drift your 225 earlyA. You have to come in way too hot, flip it into the groove and stand on it. Then the inside wheel lifts and spins and then it's all over. That's no fun at all. So how about a 273/318? Well you never have enough rear gear in a DD so it's still no fun. But If you put a big ol' performance gear in the back things are looking better. But then it won't sustain the tirespin and it's all over again. But when you finally get to a 360 and big fat skates back there, and with just 3.55s, now you have controlled throttle steer. And that is badazz fun.
Hyup; a 273 5gear Miatta; that would be badazz.
Lessee how can we get an early A down to 2400? That shouldn't take much,lol.
I think the backseat alone is 65#, 2 bumpers at 30#, the heater at 35# Empty the trunk,aluminum wheels, radio delete, manual everything shoot the P/S alone is about 300 kgs IIRC.(lol). Yeah 2400 should be doable. Now yer in badazz territory.Well OK yer just tickling it. Now pump it up to 300hp and make it stick. Then take a break,yer done. 2400/300=8 #/hp; that's badazz. Now you could be in the 11s. Lessee 300/273=1.1HP/cid, totally doable.
Course a 360 only needs .83hp /cid. That's 2bbl territory right there. And the 360 will be about as docile as a 10 year old cow. And I guess you could put the earlyA back together and run it at 2800,and pump up the 360 to 350 hp or .97 hp/cid . Still a pretty tame lump.
Tame lumps are way more fun than trying to stay on the pipe all the time. I mean just try and drift your 225 earlyA. You have to come in way too hot, flip it into the groove and stand on it. Then the inside wheel lifts and spins and then it's all over. That's no fun at all. So how about a 273/318? Well you never have enough rear gear in a DD so it's still no fun. But If you put a big ol' performance gear in the back things are looking better. But then it won't sustain the tirespin and it's all over again. But when you finally get to a 360 and big fat skates back there, and with just 3.55s, now you have controlled throttle steer. And that is badazz fun.
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