1965 Mustang 289 vs 289 HiPo engine? - Ford Mustang Forum

LinkBack Thread Tools
post #1 of 12 (permalink) Old 10-17-2007 Thread Starter
Classic Member
Erks Eagles's Avatar
Joined: Oct 2007
Location: Marietta
Posts: 10
1965 Mustang 289 vs 289 HiPo engine?

Sorry for this very stupid question, but it just shows how little I know about engines and my Mustang so far. Like I stated in a previous thread, I bought my Mustang about 3 weeks ago and the previous owners informed me the 289 engine had been rebuilt a few years ago. They stated it was a Hipo engine with 300+ horsepower. It runs great so I am not complaining about it, just curious how to tell if in fact it is now a hipo engine. The car is an automatic and I thought I read where all hipo's were manuals. I am curious about what to look for on the engine itself that can be an indicator. Car has hooker headers and flowmaster exhaust. Thanks.

Erks Eagles is offline  
Sponsored Links
post #2 of 12 (permalink) Old 10-17-2007
4.6L Member
5.0L Member
EagleAutosports's Avatar
Joined: Feb 2007
Location: Graham
Posts: 46,030
You'd have to look at the VIN number. The Hi Po 289 was engine code K, you should see it in the VIN number.

Best Car & Motorcycle Insurance | Auto/Moto Protection Today | FREE Trade-In Quote

AFM Site Administrator
Member: Mustang Club of America #82740, White Mustang Registry #362, NMRA, Fun Ford Weekend, Mustangs of Burlington

MOOG Certified Technician
For mods and sound clips, see profile and gallery.

EagleAutosports is offline  
post #3 of 12 (permalink) Old 10-17-2007 Thread Starter
Classic Member
Erks Eagles's Avatar
Joined: Oct 2007
Location: Marietta
Posts: 10
It's a code C. just curious if they increased it to a Hipo when the rebuilt it and how to check for more horsepower upgrades.
Erks Eagles is offline  
post #4 of 12 (permalink) Old 10-17-2007
Classic Member
ajusaf's Avatar
Joined: Feb 2007
Location: Miami
Posts: 189
Do a dyno on it. I'll be doing one for my 65 fastback next week. I have a 351W stroked to a 383 by the previous owner who claims to have way over 400 HP but I want to test it to see for myself and also get it tuned to make it run as good as possible
ajusaf is offline  
post #5 of 12 (permalink) Old 10-17-2007
PONY Member
Classic Member
V6 Member
Preacher17's Avatar
Joined: Dec 2005
Location: Enterprise
Posts: 433
Originally Posted by Erks Eagles View Post
It's a code C. just curious if they increased it to a Hipo when the rebuilt it and how to check for more horsepower upgrades.
You can't just increase the HP and have a Hipo motor the are a few things needed to "clone" a Hipo. The block itself is vitually identical except that it has heavier main bearing caps as this is covered most wouldn't bother to upgrade a plain 289 block and you really don't need to it will handle the HP increase well enough and putting the heavier mains on a regular block requires machining which can be expensive. A Hipo will also have a brinell tested crankshaft and will have a letter K stamped after the regular casting number, easy to fake, and again the "regular" crankshafts will do just fine anyway. The Hipo will also have a small extra counterweight that goes on the crank. More noticable is a heavier wider harmonic balancer. The Heads are also a different casting but you won't notice the differance unless you pull a valve cover. Most noticable would be the cast in valve spring pockets, regular heads don't have them there are a few other differences also but it is actually the same basic head that comes on the C code and you won't see a performance gain by using them. And finally a Hipo will come with a solid lifter Cam if it's got a hydralic bumpstick it ain't a Hipo.

If I had to guess I'd say that whoever you bought this from slapped a 4 barrel on it with a Hipo dress up kit and passed it off as a Hipo motor. Hipo's are fairly rare so I would bet against one showing up in your car if it wasn't originally equiped with one. But dont sweat it...the C code that you have is a good solid motor that will handle a lot. And if it already has all the chrome goodies on the outside...so much the better.

Depending on what has been done to the motor 300 Hp isn't out of line, but if he claimed it was a Hipo I'd question anything else he told me. Headers, an Intake-4 barrel and a decent cam will add 40 to 50 HP if it's a freash motor you're lookin' at 250-260 HP with head work a bit more. Not too bad for a "little" ol 289.

Hope that helps.


1966 Fastback
1966 Coupe
1998 GT

"Government is not the answer to our problems, government is the problem."

Ronald Reagan
Preacher17 is offline  
post #6 of 12 (permalink) Old 10-17-2007
PONY Member
Classic Member
5.0L Member
MizzouMike76's Avatar
Joined: Jul 2007
Location: St. Louis
Posts: 743
Just to play devil's advocate:

It could be the engine is not original. I have a C-Code, and if I found a K-Code and stuck it in my car, it would be a HiPo, just not a factory hipo. It could be a K-code long block with the original C-code dress. Maybe.

People that aren't Mustang people like us will have different ideas about what HiPo means. Maybe to this PO, the warmed up 289 is Hipo because it is higher in performance than it was originally.

Or maybe, someone told him "hey man, you got a HiPo in your Mustang!" and he believed it, and he's just trying to be helpful.

Frankly, I think you are better off without the K-code. The mechanical cams are noisy and require very accurate adjustment of the valves. They are more of a high RPM engine, and, in my opinion, not fully taken advantage of by the average daily driver. Having something rare is great, but then you have something rare. I'd rather have something common (like a Mustang), and make it 'mine' (like my Mustang).

Again, not necessarily what I think happened or the most likely scenarios, but they certainly warrant consideration.

1966 289-2V C-4 Convertible. 2nd owner, resurrected rustbucket. Factory console and power top, conversion to P/B with dual res MC.

1990 GT 25th Anniversary 5.0 AOD Convertible. SOLD
MizzouMike76 is offline  
post #7 of 12 (permalink) Old 10-18-2007
SHELBY GT 350 Member
Classic Member
Veronica's Avatar
Joined: Dec 2003
Location: Houston
Posts: 9,200
Hello. If it is a K code motor, obviously, it would have K code heads. On a K code head, there will be a number cast into the front outboard side of the d/s head and the rear outboard side of the p/s head that will be either a 19, 20 or 21. If it's anything other than this, it isn't a K code head. They also have screw-in rocker studs instead of the press-in type, and the valve springs sit in pockets to keep them from scooting around at high rpms. Here's a couple of pictures. Hope that helps.
Attached Thumbnails
Click image for larger version

Name:	number.JPG
Views:	10918
Size:	81.1 KB
ID:	34765   Click image for larger version

Name:	rocker studs.JPG
Views:	8586
Size:	91.9 KB
ID:	34766  
Veronica is offline  
post #8 of 12 (permalink) Old 10-20-2007
PONY Member
Classic Member
302THEBOSS's Avatar
Joined: Jul 2006
Location: Danbury
Posts: 517
Alot of people add aftermarket stuff or better stuff and call it a HiPo because it is, in their minds, hi performance. Stick the HiPo cam into a C code, flat mill the heads to the correct compression, get the exhaust manifolds and intake and carb and youre making MORE power than one because the advertised compression ratio was higher than the true number. Most of the HiPo stuff isnt worth it unless you have a K code car, and then its just a value thing. Theyre nice to say you have though, but as stated the heads are virtually the same save for screw in rocker studs, they wont flow any different. If you really want power look to some 351 heads. Now im rambling, but good luck.

I like to let 'em stick with me for first and second, then I put the hurt on 'em when I chirp third ~

1967 Plymouth GTX, work in progress.
440 cubes (thats 7.2 litres for you modern guys)
375 horses
480 ft lbs of torque
MODS: Direct Connection Purple Shaft cam
302THEBOSS is offline  
post #9 of 12 (permalink) Old 10-27-2007
Hipogt's Avatar
Joined: Oct 2007
Location: Central
Posts: 29
I know I am way late on this one. Nice post Veronica, stole my cast #'s and screw in rocker studs. Only 3 K-things to add. Slotted pushrod guides(see in V's nice pics) cast in head allowing you to use a HD non-rail rocker that would sustain higher RPM's. Last is the combustion chambers which were 49cc vs. 54cc(don't quote on those #'s) to give it a 10.5 compression ratio, .5 higher that the A code, as the pistons were the same.


ESP 1966 K-GT F/B - Sold
Next ESP build - 96-98 Cobra?

Hipogt is offline  
MACH I Member
Classic Member
5.0L Member
The Greek's Avatar
Joined: Nov 2006
Location: Jacksonville
Posts: 3,165
Let's not forget the use of 3/8 inch vs. 5/16 inch connecting rod bolts and the slight mod to the rods for the use of the larger bolts.

This is why there is a counterweight installed on the crankshaft before the balancer. It's to compensate for the added weight of the larger rod bolts and nuts.
The Greek is offline  
BobinCovington's Avatar
Joined: Aug 2010
Location: Covington
Posts: 1
It's not in a Mustang but shares a lot of the same history. Just for a reference, here is a HiPO 289 from 1966. My dad bought ordered it and had Dave Zeuschel balance and build it into a great engine for the little 66 Ski Sporter Donzi. Dyno'd at about 261 horsepower and has an isky cam, mondello modified heads and edlebrock intake.

It still runs, has about 300 total engine hours or less after all these years of having it in the family and we did a little work to bring it back on line this summer. With the oil pan off you could see the heavy duty components. My mechanic was showing me all that went into the hipo engine. Firing order was different though. It sounds so nice with no mufflers...
Attached Thumbnails
Click image for larger version

Name:	engine side view.jpg
Views:	5436
Size:	189.5 KB
ID:	108065   Click image for larger version

Name:	Donzi at Scott Pierces shop.jpg
Views:	3536
Size:	266.9 KB
ID:	108066   Click image for larger version

Name:	Donzi 289 engine side view 2.jpg
Views:	1416
Size:	10.1 KB
ID:	108067   Click image for larger version

Name:	Engine going back in 1.jpg
Views:	3531
Size:	706.3 KB
ID:	108068   Click image for larger version

Name:	Engine out.jpg
Views:	8767
Size:	961.3 KB
ID:	108069  

BobinCovington is offline  
BOSS Member
Classic Member
rex1965's Avatar
Joined: Jan 2010
Location: Pittsburg
Posts: 4,552
Also the HIPO had dual points, and did not have vacuum advance on the distributor. And one last note I've ran the 289 271HP hipo cam in my 65 since 1974, and the only time I need to adjust the valve lash, is when it starts to get noisy, which is about once every two years or so, and it takes about 30 min to do, I run isky valve springs which have alot more spring pressure than the stock ones, retainers, and keepers, I turn it up to 7500 rpm, it has not been rebuilt since 74, but it is due. I love the clatter of the valve train, it has a nostalgic sound, just like my cherry bomb mufflers. Good Luck.
rex1965 is offline  
Sponsored Links
Closed Thread

Quick Reply

Register Now

In order to be able to post messages on the Ford Mustang Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a VALID email address for yourself, otherwise you will not receive the necessary confirmation email needed to confirm, validate and activate your new AFM member account.

Failure to provide a VALID email address, will result in the cancellation of your new AFM member account registration.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are On

For the best viewing experience please update your browser to Google Chrome