Shelby Intakes

There are several different intakes used on 65 GT350's ,all had the small letter COBRA.The small letter COBRA should be the main criteria in determining if it is a 65 Shelby intake.The repro intakes are a S2MS with large letter COBRA,not S1MS and they are easy to spot because the heater hose fitting hole is too big.I hope this helps.

 

The early 65 GT-350s had a small letter cobra intake without a part number, the later ones had the S1MS part number on them. There were some repop S1MS intakes made in the 80s. The real ones have four round holes where the carb goes, while the repops have two big oblong holes. The real ones were made by Offenhauser and have their logo cast into a pedestal on the bottom side of the intake that's about one inch in diameter.

 

I don't believe the early S1MS repro intakes had small letters ether. Don't forget the 3rd type of small letter Cobra intake which was used on the R models. This is a small letter intake which had the S1MS and did not have the PCV port drilled or threaded or the normal temp sender port drilled . The port normally used for the heater hose elbow was drilled and threaded as normal and used for a mechanical water temp themo coupler.

 

There were some of those repops with the small letters. I had a guy trying to sell me one of them a few months (couple of years?) ago. On some of them you pretty much have to either pull the carb or look at the bottom of the intake to tell. Especially now that they've had some time to get old and funky looking. But, if a person is buying one, it probably isn't on a car, so flipping it over and checking for the offy logo is the way to know for sure. I guess the bottom line would be, if a person is looking to buy an S1MS intake, to do their homework and discuss it with people that know exactly what they are looking at. Personally, when I'm looking to buy a part, no matter what it is, I like to see the entire part before I cough up any money. The intake should have the offy logo on the bottom of it.
I'm pretty sure that intakes without the pcv hole drilled out were used on all of the competition cars, not just the R models. At least, we did a rotisserie restoration on one of the 66 drag cars here a few years ago and it had one of those in the trunk when it got here, so I guess it was original to that car, since it was a carry-over car, but maybe not. Who could really say for sure?

 

I know the intakes with out the pcv and temp sender drilled were made to be used on the R Models first but it would have been logical for them to be used on the 1966 Trans Am coupes, Dragon Snakes etc. also.

 

Remember ...these small letter intakes came on 289 Cobras, (...cobra intake). I would venture to guess that many were sold over the counter and wound up on hot rods..Dealers installed them on falcons and comets (and Galaxies) with V8's ect. Road tube cars (pre-65). don't need a PCV inlet. There was a running change at ford with regards to the temp gauge sender diameter.. small 64??/ big 65++
Small letter intakes are hard to find in any version. and are always very expensive because of that..
jimbo

 

You can look down the carburetor with a flashlight and see if the intake has four individual holes or an enlarged "log"

jimbo

 

Jim, the small letter S1 aluminum intake has a boss cast in for the pcv to be drilled. If it was designed for a non pcv equipped car that blank boss would never have been engineered into the casting. Now that you mention it I think there was a earlier version of the small letter Cobra intake that didn't have a pcv boss engineered into the casting and that must have been the style that was available for upgrades on the 289 cobra and other performance engines of the day. That style would make 4- 1.no pcv. provision + no S1MS, 2.No S1MS with the pcv drilled, 3. S1MS marked with the pcv drilled and 4. S1MS marked without the PCV or temp sender drilled for R model and later Drag race/Trans AM use. There might even be 5 in al if there was a version of a non S1MS marked intake without the pcv or temp boss drilled for race applications. I myself have not seen one but it is likely. I would like to make a point that since the newer version intake came out because it was designed to normally go on the new for 1965 pcv equipped GT350 cars that the R model was most probably the first application for this type of Cobra intake for race applications were the pcv and temp sender boss was left undrilled. That same intake later found it's way on every other Ford performance application under the sun. Jim, also if you check you will find that all 1965 GT350 used the small temp sender. You might have gotton confused about the fact that I mentioned that the race versions used the heater hose fitting hole for the larger Stewart Warner mechanical temp sender which is a thermo coupler instead of drilling in the normal spot. Only when the carryover cars were used up in early 66 production did Shelby switch to the larger style sender. Jim, the 289 Cobra had the 289 hipo 4 bbl cast iron intake and carb as standard equipment . The vast majority of Cobra intake/carb upgrades were done as owner installs. It goes without saying but I will ,that some were done at Shelby as options and some at dealers for the first owners.The 289 Cobras were fast as it was and a upgraded intake and carb was not a issue when it was conceived. The 65 GT350 on the other hand had to have the induction and exhaust upgrades to make it more different then a standard 289 hipo mustang.

 

All of this is interesting.
Has anyone ever seen a 4 holer with a small pvc, no part no. and no offy on the botttom?

 

Thanks Bob,
Information is so much more enjoyable than .."no that is wrong"
Here is a picture from one of us.

http://www.shelbyforums.com/forums/15627-post5.html

this one has no PCV boss ...small temp sender hole (oval hole??? )
Regards,
jimbo

 

Real early COBRA high rise, reported to have come from one of the three Cobras factory equipped with them (per SAAC Registry 1997). Note the machining connecting right and left sides on the carburetor mounting pad. I have only seen three real early light weight thin wall castings just like this and the sellers of two of them had Cobras at one time. Oddities include:
• no engineering number
• no firing order
• no PCV boss
• left and right banks connected by flycuts under the carburetor
• super thin wall casting CANNOT HAVE PORTS ENLARGED
• CANNOT BE USED WITHOUT A SPACER, the mounting stud holes are offset to the rear about 1/16 inch, installing a List-3259 or 3259-1 without a spacer results in the throttle plates hanging on the intake manifold holes. A wedge shaped spacer allows the throttles to open.

The lack of a PCV boss puzzles me still because all but they very first few Cobras had a PCV valve either from the back of the intake manifold (early) or off the left side valve cover (late) AND racing for Cobras generally meant Webers. So why was an intake created without a PCV port if it was intended for a street car?

The S1MS-9424-A, S1MR-9424-A, S1MK-9423-A, S1MK-9423-B, and S1MS-9424-C are all listed as the same price as the option cost for the Cobras with a high rise BUT THE KITS OFFERED IN 1965 CAME WITH PCV BRASS FITTING per the Shelby American Inc. 1965 parts book.

There was also a bare unmachined casting from Buddy Bar (not Offenhauser) offered under S1MS-9425-A for $29.61 in 1965 Shelby catalog.

I have seen many different “small letter” intakes since I bought my first 1965 GT350 in the 1970s and thought I had perhaps seen them all when a dealer sent me an image of another version he found that had the Offenhauser identification under the heat shield.

 

Great thread. I don't know how I missed this before I posted the other night.

http://www.shelbyforums.com/forums/...g-gt350-gt500/6740-s2ms-intake-questions.html

To answer my own question from my other thread, it seems like the one I have was a competition version for sure, (especially since it says "DRAG RACE".....duh), has the PCV boss undrilled, the temp sensor boss undrilled, and the big heater hose port (for the thermo couple). And also the flycuts at the carb base. Did I get that right?