XHP 260 and aluminum blocks

[alexopm]

Originally Posted by Dan Case

All the known that I can document XHP-260 and HP260 engine blocks are cast iron; I have documented one XHP-260 casting and two different ones used in HP260s. The various versions of cylinder heads on XHP-260 and HP260 engines in Cobras have been cast iron also. From my Weber/Cobra database the cross ram system was designed and built by Shelby's team. Legend says it was too complicated to make and difficult to tune compared to the benefits. The prototype side draft and three prototype down draft systems are included in evaluations that I have documented in some way or another. The side draft design was abandoned. CSX2043 used #3 of 3 down draft prototype systems., I owned that 3 of 3 system for a few years but now it resides in an early Cobra again.

I have no idea how many XHP-260 engines were made by Ford but CS probably wasn’t the only one to get them. At the time Falcon rally cars were being raced by Holman-Moody. The highest serial number that I have found recorded in period is fourteen (14). Based on published information serial numbers 1, 2, 4, 5, 8, and 14 were installed in very early Cobras.


XHP-260 Engine #4 survives to this day in unrestored form. It was carefully dismantled, extensively photographed, analyzed dimensionally (things like camshaft details), reassembled and shown in public on a display stand a few years ago by Bob Mannel. The engine block was originally stamped serial number 2 but was changed to number 4. Many of the internal small parts are engineering specials and some appear to have been made one at a time on a lathe or mill. All the handmade prototype parts carried individual serial numbers in that engine, not for the engine assembly but for the parts themselves. It is an interesting engine. The effort to document what was in engine four was a three way arrangement among the owner of the engine, me, and Bob Mannel who did all the work. Whenever Bob updates his engine book this engine is to be included.


There isn’t much in comparison between a XHP-260 with very many engineering special parts and an almost production HP260. The information around indicates that Ford was planning to offer HP260 engines in Falcons. The European rally cars used HP260s and Dearborn Steel Tube outfitted a Falcon for testing as a production ready test car but the release of the HP289 engines ended all of that apparently.


Specific details of what was in engine 4 are way too long to include in a web post, certainly the dozens of close up pictures wouldn’t fit.

Dan

PS. There might be a clue to how many XHP-260 engines were made in a “day two” picture of CSX2000 and engine XHP-260-1 in it. The earliest photo of XHP-260-1 being installed in the car that I have seen published shows a vacuum advance ignition distributor with vacuum line installed. Pictures taken not long after show a fully mechanical distributor. The Ford engineering stickers on the second dizzy calls out an experimental engineering assembly number and that it is unit number 6 of 35. We will probably never know for sure.

Hi Dan. XHP 260 -4 was fitted in the De Tomaso Intercontinental/Formula Libre car that was purchased by John Mecom Jr in 1963. There are pictures of the engine in the car during a photo shoot in Modena, before shipping it to the USA. This was before the P70 project. Mecom didn´t use the car beyond some testing, and it was later sold to Bill Frank, who raced it with a 3 litre engine. I don´t know when #4 was removed from it (if before or after the purchase.