'65 Mustang Hi-po vs '65 Formula S

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My 1st car was a '66 Barracuda Formula S Commando 273/auto (still have it) and one of the other kids at my high school had a '66 Mustang 2+2 289 4 speed with typical 80's mods, Holley "double pumper, headers ETC.
We got into it on Dixie Hwy one night traffic light to traffic light.
At the first one he yelled "that big window is the stupidest thing I have ever seen!!!"
I said " it's gonna look smaller in a second!!"
Then the light turned green and I got the hole shot ( launching a 4 speed can be hard on bias plys) and I gapped him by 2 cars to the next light.
Did it 2 more times before he turned left and hid.
He avoided me like the plague around school after that.

Good times..
 
I had a 273 Hp Barracuda, my brother had a 65 Mustang coupe as kids. We built the 289 into a K motor with factory K rods, cam, Offy intake, 440 AVS, and a 3.90 limited slip 9" out back. It was pretty stinking fast. Biggest problem was trying to keep a C4 automatic alive behind it. He said it broke into the 12's one of the few times he took it to Thunder Valley Dragways in Marion, SD. He could have cared less.

 
1966-7 back in South Ga. there was a college kid at Tifton that has "purpose" bult 289 Stang, 4 speed. He ran for $100 anywhere and anybody there was a country 1/4 mi. flat spot, and rarely lost.
 
In general the Hi-Po 289 had the edge on the 273 Commando depending on drive rear axle etc.
But the Barracuda had superior handling.
 
In general the Hi-Po 289 had the edge on the 273 Commando depending on drive rear axle etc.
But the Barracuda had superior handling.
I agree. But the hi-po 289 had a much hotter cam than the 273 Commando. Better comparison would be vs. the 289 four barrel. 225 hp rating vs. 235. Stock to stock, 273 was an easy winner. Just based on my own experience.
 
BTW, you have to read these old road tests with some skepticism. There's an old Car and Driver or Road and Track (can't remember which) comparison between a 289 hi-po Mustang and a 273 Commando Barracuda. They had the Commando 273 being no faster than a 273 2-barrel, and the Mustang running the quarter almost THREE seconds faster.

And then there's Motor Trend's test of a 58 Chrysler 300 with a 375 hp 392 and Torqueflite showing it being slower than their own earlier test of a 55 Chrysler 300 with a 300 hp 331 Hemi and two-speed Powerflite trans. (17.9 vs. 17.5)

The 67 383 Barracuda tested by Super Stock and Drag Illustrated was half a second quicker in the quarter than any other magazine's 383 A body because they shifted its Torqueflite manually instead of leaving it in drive and letting it upshift at just over 4,000 rpm.

I could go on, because there are plenty of other examples . . . .
 
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1966-7 back in South Ga. there was a college kid at Tifton that has "purpose" bult 289 Stang, 4 speed. He ran for $100 anywhere and anybody there was a country 1/4 mi. flat spot, and rarely lost.
He shifted by earand took the carhome every weekend for a "tune"> He swor it as stoke but we knew it had to be way more, maybe Carrol Shelby touched that engine maybe? He outran everything on a reguar basis.
 
289 is one of my favorite Ford engines. Even in 2bbl form, they were runners. Especially if they had a stick shift behind them. Might be the fastest 2bbl "cubic inch per cubic inch" motor I've seen/driven?? No 283 2bbl or 273 2bbl would even be in the ball park. I've owned them all.
 
He was a student at ABAC?
Yes we were there from 66-67 or I actually attended summer qtr of 66 thru fall of 68, 8 qtrs that should have been 6!!!!!! ha The draft lady siad, "boy, you are a gnats away from toating a rifle there in Nam". And just like that....... I transfered to UGa. and it was way easier up there in that big school. My old dad that spent 25 years in the USMC and two wars said :"If they draft ya , ya gotta go, BUT>>>>>IF ya join, I will kick your f**** *** from her to there (eternity??)". Quote unquote.

What does that have ot do with hot 289s???? !
 
Well, in August of 68 my Dad bought my 65 Barracuda with a Commando 273.

We were living in Cochran at the time. He taught at Middle Georgia College. I don't remember any fast Mustangs around Cochran. Not sure I ever saw a hi-po 289 Mustang on the road. Maybe in other parts of the country they were more common.
 
I agree. But the hi-po 289 had a much hotter cam than the 273 Commando. Better comparison would be vs. the 289 four barrel. 225 hp rating vs. 235. Stock to stock, 273 was an easy winner. Just based on my own experience.

64-67 HiPo 289 was rated at 271 HP (they made 489 '67 K-codes too). It only had a 90 day or 4K mile warranty on it.

Commando 273 is rated at 235 HP.
 
I agree with you autox, although I'm not exactly sure what your point is. To me, the respective hp ratings (as well as the difference in factory warranties) indicate that the 271 horsepower HiPo 289 and the 235 horsepower Commando 273 were not and were not intended to be comparable engines. More comparable to the HiPo 289 would be the D-Dart 273, which was rated at 275 hp.
 
I agree with you autox, although I'm not exactly sure what your point is. To me, the respective hp ratings (as well as the difference in factory warranties) indicate that the 271 horsepower HiPo 289 and the 235 horsepower Commando 273 were not and were not intended to be comparable engines. More comparable to the HiPo 289 would be the D-Dart 273, which was rated at 275 hp.

I think they are somewhat comparable. It was just a hotter motor of the dealership floor. Still very street-able and they made over 12,000 64-66 Mustang with them. Of course they made over 1 million 64-66 mustangs. Mopar was just strong with it's warranty. And used it as a selling point.

IMHO, the D-Dart was a special extremely limited production drag race package. Not really advertised to general public. No brochure mentions.

Now for 1968, the Mopar 340 motor was stronger than even the a 302 installed in GT350's. Those were regular 302 with bolted on aluminum intake and holley carb. I think the 69-70 340 was stronger than the 351W and 351C motors too.
 
I think they are somewhat comparable. It was just a hotter motor of the dealership floor. Still very street-able and they made over 12,000 64-66 Mustang with them. Of course they made over 1 million 64-66 mustangs. Mopar was just strong with it's warranty. And used it as a selling point.

IMHO, the D-Dart was a special extremely limited production drag race package. Not really advertised to general public. No brochure mentions.

Now for 1968, the Mopar 340 motor was stronger than even the a 302 installed in GT350's. Those were regular 302 with bolted on aluminum intake and holley carb. I think the 69-70 340 was stronger than the 351W and 351C motors too.
Well, I can't really argue with any of that. I do wonder why Chrysler Corp didn't put a hotter cam in something they were going to call a "Commando" 273. The cam in the 273 four barrel was barely hotter than the two barrel 273, and a lot milder than the 289 hi-po. I know when I put a hotter cam in my 273, that really woke it up.
 
In 1965 my mom worked at Ralph Williams Chrysler Plymouth in West Seattle. She was offered a new 1965 Barracuda at cost. She picked the options that were not on most customers order sheets. It was a Robin egg Blue with a white stripe, Commando 273, 4 speed with a Suregrip 3.91 gear 8 3/4. It was fast but my mom did not drive it hard. We has a small camp trailer that she towed with it.

Fast forward to 1974, I was a PFC in the Army and my mom loaned it to me. I was not allowed to hop it up. But it was running bad so we did a compression test and #2 cylinder was dead. The camshaft had no lobe intake left. I had the cam replaced with a Hyd 262 degree RV cam. That was the only change I could do.

I was out at Ft Lewis WA and one of my team members has a stock 1966 Mustang GT and we went out on range road and lined up one day. It was 3 out of 5 runs that I won but not by too much. The 9 1/4 inch clutch was slipping too much.

In 1980 I had to sell it due to going to Germany.

Then in 1986 I found it for sale. VIN was right. It was pained BLACK, had a 383 4bbl, A727, Ford 9 inch and LBP all around. Has tall back Ford Bucket seats.

The guy bought it as a project for him and his son. But son's school grades were in the toilet so dad put the Barracuda on the market to scare the son, did not work. A month later I was driving by and seen the 'For Sale' sign and $700 later it was mine again. Still have it.

I love small towns.
 
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But in 1977 while at Ft Or CA, I bought a rust bucket 1965 Shelby GT350. You could put your fingers thru the floorboards, no trunk pan, fenders had holes too.

But the 289 ran real well. We gutted it and put the whole Shelby package into a 1965 Ford Ranchero.

That Ranchero was the fastest pickup I'd ever been in. The Shelby body went to make 2 Toyotas, well maybe 1. It was worthless back then.
 
Well, in August of 68 my Dad bought my 65 Barracuda with a Commando 273.

We were living in Cochran at the time. He taught at Middle Georgia College. I don't remember any fast Mustangs around Cochran. Not sure I ever saw a hi-po 289 Mustang on the road. Maybe in other parts of the country they were more common.
There at ABAC in 66-67 there were 442s, GTOs, All dinds of Fords, few Mopars, even Jag. Most everything. All kids of cool cars. Most cool cars were just transportation that got there a little quicker and cooler!
 
My first Cuda was just a 273 with a 2bl in 1975 but I snuck up on my buddy with the same 289/2bl in his Mustang and before he knew it was me - we were dragging down Westmoreland here in Big D by the old Gibson's......I pulled him by half a fender ! Owned and drove a 1965 2+2 and would pick a A - body Cuda ANYDAY !
 
Well, I can't really argue with any of that. I do wonder why Chrysler Corp didn't put a hotter cam in something they were going to call a "Commando" 273. The cam in the 273 four barrel was barely hotter than the two barrel 273, and a lot milder than the 289 hi-po. I know when I put a hotter cam in my 273, that really woke it up.
How Hot was it?
Would you Consider This One Hot for a 2bbl Motor?

cam.jpg
 
In 1965 my mom worked at Ralph Williams Chrysler Plymouth in West Seattle. She was offered a new 1965 Barracuda at cost. She picked the options that were not on most customers order sheets. It was a Robin egg Blue with a white stripe, Commando 273, 4 speed with a Suregrip 3.91 gear 8 3/4. It was fast but my mom did not drive it hard. We has a small camp trailer that she towed with it.

Fast forward to 1974, I was a PFC in the Army and my mom loaned it to me. I was not allowed to hop it up. But it was running bad so we did a compression test and #2 cylinder was dead. The camshaft had no lobe intake left. I had the cam replaced with a Hyd 262 degree RV cam. That was the only change I could do.

I was out at Ft Lewis WA and one of my team members has a stock 1966 Mustang GT and we went out on range road and lined up one day. It was 3 out of 5 runs that I won but not by too much. The 9 1/4 inch clutch was slipping too much.

In 1980 I had to sell it due to going to Germany.

Then in 1986 I found it for sale. VIN was right. It was pained BLACK, had a 383 4bbl, A727, Ford 9 inch and LBP all around. Has tall back Ford Bucket seats.

The guy bought it as a project for him and his son. But son's school grades were in the toilet so dad put the Barracuda on the market to scare the son, did not work. A month later I was driving by and seen the 'For Sale' sign and $700 later it was mine again. Still have it.

I love small towns.
Wait a minute...is it back to blue, 273, 4 speed, and 3.91 now ?
 
In 1965 my mom worked at Ralph Williams Chrysler Plymouth in West Seattle. She was offered a new 1965 Barracuda at cost. She picked the options that were not on most customers order sheets. It was a Robin egg Blue with a white stripe, Commando 273, 4 speed with a Suregrip 3.91 gear 8 3/4. It was fast but my mom did not drive it hard. We has a small camp trailer that she towed with it.

Fast forward to 1974, I was a PFC in the Army and my mom loaned it to me. I was not allowed to hop it up. But it was running bad so we did a compression test and #2 cylinder was dead. The camshaft had no lobe intake left. I had the cam replaced with a Hyd 262 degree RV cam. That was the only change I could do.

I was out at Ft Lewis WA and one of my team members has a stock 1966 Mustang GT and we went out on range road and lined up one day. It was 3 out of 5 runs that I won but not by too much. The 9 1/4 inch clutch was slipping too much.

In 1980 I had to sell it due to going to Germany.

Then in 1986 I found it for sale. VIN was right. It was pained BLACK, had a 383 4bbl, A727, Ford 9 inch and LBP all around. Has tall back Ford Bucket seats.

The guy bought it as a project for him and his son. But son's school grades were in the toilet so dad put the Barracuda on the market to scare the son, did not work. A month later I was driving by and seen the 'For Sale' sign and $700 later it was mine again. Still have it.

I love small towns.

The standard motor in the 65-66 mustang GT was the 225HP 289cid A-code motor.

The HiPo 271HP K-code was optional. And while they built over 12K K-codes, they built over 3 million 64-66 mustangs.

That makes the relative rarity of k-code among all 64-66 Mustangs (0.4%) greater than a 1970 Hemis in Barracudas (1.1%).

Also, standard rear end ratio on a A-code 64-66 mustang is 3.00 or 2.80.

Performance Mopar’s usually had deeper gear standard equipment than their GM or Ford counterparts.
 
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The standard motor in the 65-66 mustang GT was the 225HP 289cid A-code motor.

The HiPo 271HP K-code was optional. And while they built over 12K K-codes, they built over 3 million 64-66 mustangs.

That makes the relative rarity of k-code among all 64-66 Mustangs (0.4%) greater than a 1970 Hemis in Barracudas (1.1%).

Also, standard rear end ratio on a A-code 64-66 mustang is 3.00 or 2.80.

Performance Mopar’s usually had deeper gear standard equipment than their GM or Ford counterparts.
So, my 273 4bbl had 235 HP @ 2675 pounds curb weight (0.0879 HP per pound) and his 289 4bbl has 225 HP @ 2650 pounds curb weight (0.0849 HP per pound).

In my above post, our 5 runs, I won the first race by a car and the next 2 by a door, lost the next 2 by a fender as my 9 1/4 inch clutch was slipping each time. Let the clutch cool and it did not slip much.

273's clutch pressure plate had 3 springs in all the 3 places. I had it rebuilt with 4 springs of heaver wire diameter springs. It was HARD to step down on but it did not slip much. Later bellhousings allowed a 10.5 inch clutch.
;)

Clutch.jpg
 
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So, my 273 4bbl had 235 HP @ 2675 pounds curb weight (0.0879 HP per pound) and his 289 4bbl has 225 HP @ 2650 pounds curb weight (0.0849 HP per pound).

In my above post, our 5 runs, I won the first race by a car and the next 2 by a door, lost the next 2 by a fender as my 9 1/4 inch clutch was slipping each time. Let the clutch cool and it did not slip much.

273's clutch pressure plate had 3 springs in all the 3 places. I had it rebuilt with 4 springs of heaver wire diameter springs. It was HARD to step down on but it did not slip much. Later bellhousings allowed a 10.5 inch clutch.
;)

View attachment 1716108033

My original 273 4-barrel clutch lasted 90,000 miles and a bunch of speed shifts. Finally crapped out. Local parts store replacement clutch was garbage. Couldn't speed shift it even when new without slipping badly. Tried a couple different ones, finally figured out that although the catalogs listed what I was given as a 273 four barrel clutch, they were really six cylinder clutch assemblies. Finally found an actual Commando 273 clutch disc and paired that with a Weber pressure plate. Boy that would wear out your knee if you didn't put the trans in neutral at a long light, but it also didn't slip. Only problem was that after two years, one of the release fingers would bend and the clutch wouldn't fully disengage. After the second one did the same thing, I converted to a 340 clutch. Found that even a local parts store 340 clutch couldn't be speed shifted without slipping. Switched to aftermarket (Zoom, etc) which at the time would actually be in stock at your local speed shop. They worked, but wore out relatively quickly compared to my original clutch. Went through several of them (I've owned the car for over 50 years), then switched to a Centerforce dual friction clutch, and it's lasted longer than anything else I've ever run. Only problem is it bites so hard I've gotten afraid to speed shift it, but I haven't raced anything in a long time so the tenth or two I lose by not speed shifting doesn't matter.
 
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