65/66 Shelby 289 block...

[thomas butt]

Did the 65/66 Shelby GT350 or AC Cobra come with a four bolt block? A guy selling a car says he has a four bolt Shelby block in his car.

[SupStk]

Never heard of it. Take a look at any ‘65 and later 289 block, there is no material to accommodate 4 bolt caps. The 271 hp engine (K code) had thicker caps from the factory.

[thomas butt]

Thank you for that. I had never heard of one and when I googled ‘4 bolt Shelby 289 block’ nothing came up.

[1972ho]

He might just have one of these SK or XE blocks in it if so it’s a pretty rare deal.

[PackardV8]

He might just have one of these SK or XE blocks in it if so it’s a pretty rare deal.

So rare I was there in the day building SBFs and never, ever saw one.

All the '65-'66 Shelby GT350s and Cobra 289"s I ever saw came with standard K-code HiPo 271hp Ford 289" with a Shelby aluminum intake and rocker covers. And yes, all K-codes had the nodular iron two-bolt main caps. IIRC, the first production 4-bolt small block Ford was the '68 Boss 302"; which BTW I never saw used in Shelbys or Cobras.

[1972ho]

I’m just saying someone could have found one these blocks some time ago and put it in the car,not saying it’s original to the car.

[thomas butt]

He might just have one of these SK or XE blocks in it if so it’s a pretty rare deal.

He is giving me a part number of C5AE-6015E for the block

[Rick!]

I mechanically restored a 64 289 4 Weber Cobra and serial number 051 65 GT350 and neither had 4 bolt mains.

[1972ho]

That is the casting number for a HIPO 289 2 bolt block should not be 4 bolt main.

[thomas butt]

That is the casting number for a HIPO 289 2 bolt block should not be 4 bolt main.

Ok. Thanks for that. I read that the hi po 289 blocks were inspected for cracks so they Had fewer imperfections

[Krooser]

Talking about rare blocks...

My son built an F100 with a 289 Hi-Po engine from a '65 Mustang.

When he opened it up to take it to the machine shop I took a look and the lifter valley had a cast logo for the Waupaca Foundry. Back then they were small but now are the world's largest grey iron foundry.

I knew the top two guys at WF so one day I asked the head honcho (who had been there since the 60's) how many 289 blocks did you guys cast for Ford? He said they never made any engine blocks for Ford. I showed him a photo of the logo... he shook his head in disbelief. Said he could never remember doing those blocks.

I had heard of those four bolt castings back in the late 60's... never saw one. We ran a hi-po 289 for two seasons in our dirt sportsman in the late 60's... ran faster then our H-M 427's....

I also have a 318 Mopar from the mid-70's with the IHC logo on it. When I bring that thing up to Mopar purists I get the same dumbfounded look as I got from Gary at Waupaca Foundry.

[piston guy]

XE cranks ( and SK cranks) were made in cast and forged , I have both. Often times the XE or SK number was created to call out a different bob weight specification or in some cases material. You also have a picture of a head ( from the internet) and call it a 289-302 canted valve prototype . XE244963 is actually a "never produced" V8 Probe ( nay Mustang) designed in the '80s when ford was considering dropping the Mustang name. I am good friends with the engineer who designed it and have one sitting next to my desk right now, It is NOT a real "high performance" head despite it's racy looks. The valves are about 1.850 x 1.550. The ROUND intake ports are only 1.780 in dia and the round exhaust is 1.500. A Cleveland valve cover will not bolt on as the bolt pattern is different.

[ProPower engines]

Thank you for that. I had never heard of one and when I googled ‘4 bolt Shelby 289 block’ nothing came up.

Does it use a 5 or 6 bolt bellhousing??
The 1st 289 blocks were 5 bolt bellhousings

[frnkeore]

I believe, to be original to the Cobra, they have to be a 5 bolt belhousing pattern.

In the late 70's (I believe '79), I sold two of my, 271 HP blocks to a Cobra restorer and that is what he told me.

[n2omike]

I have been into small block Fords since at 15. I'm 52 now. The photo above is the ONLY picture of a 'factory' albeit experimental small block (not Boss 302) I have ever seen. ZERO came from the factory with a 4 bolt main. ZERO. This is the first time I have even heard of a valid example. In other words, your 'buddy' does not have a 4-bolt main HiPo 289. ALL of them were 2-bolt. A 4-bolt 289 was never offered over the counter or in a catalog. They were one-off experimental or race only. The average person could not buy one... even if he really wanted to.