Club Cobra - Dual Quad on 351 Help

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Dual Quad on 351 Help

I am interested in installing a dual quad setup on my 351W in my Cobra. I like the Blue Thunder manifold since it takes Holley carbs instead of the Edelbrocks. I thought about turning the carbs around backward and manufacturing a progressive linkage setup like on the 427 motor. I know I will have to purchase a set of adapter plates from Price Motorsports since no one makes a 351W dual quad manifold. Is anyone out there running a similar setup and could offer me any advice or suggestions such as:which Holley carbs to buy; any known problems or considerations?

I recently installed a dual quad setup on my 351 Cleveland. I fabricated the intake myself from an Offy 360 single 4. Adapter plates were not available for my engine. I wasn't sure it would work, but the results have been great. I use 390cfm Holleys (Turned around backwards) with vacuum secondaries, with the linkage from a 427 Med Riser. In my case, everything fit perfectly. I also had to go with a standard size dist. cap for clearance. I think these carbs would work well in your application also. Drivability is Great! Looks are even better! You can see pictures in my gallery. It was a lot of work, but worth it. Let me know if I can give you more info. Later, David Shelton.

David,

That is really impressive. You have done some really nice work. I was looking to do the same thing that Superhart wants to do but when I saw a picture of how the 351w with the 302 dual 4v manifold and adapterplates I just didn't like the look. For one thing the adapter plates are very visible. Secondly I'm pretty sure that you have to use a different style carb because the carb spacing is closer. The effect is that you have to use smaller air cleaners and in my opinion it just doesn't look right. Your custom setup looks great! It looks just like the 427 setups I've seen.
I still want the dual 4bbl look some day so when I order my car I'm taking the easy route and getting the 460. (Dual 4bbl manifolds are readily available for the 460)
Once again nice work!

John

Re: carb spacing, that is why I chose the Blue Thunder manifold. If you use an Edelbrock or Offy 2x4 manifold you must use Carter or Edelbrock carbs and the spacing is very close, 6 1/2" center to center I believe. Manifolds by Blue Thunder and Holman Moody use standard 427 carb spacing so Holleys are the way to go and you can use the oval dual quad Cobra air cleaner if you want the setup to look like the Shelby Mustang. For the record, if you look closely at a 427 dual quad cobra you should note that the S/Cs used dual S&H air cleaners with the rear cleaner using a lower profile filter element than the front to achieve hood clearance.

I have seen the Price adapters on a 351W engine and if they are painted to match the block and heads you have to look closely to notice them. Plates are also available to adapt the 302 manifold to Cleveland heads. I do admit that the most desirable way would be to use a manifold made for the 351W. I have long wondered why no one makes a 2x4 manifold for the 351W when it seems that all other Ford engines have one available.

I was thinking about the chokeless mechanical secondary 450 cfm Holley from the cost standpoint. Anyone have any experience using them?

Thanks, John for the compliment. Super,I would think twice about using the 450 mech. Sec. on such a small engine as 351. Vac sec are much more forgiving and much more streetable. To my knowlege, Ford never put mech secondaries on anything. Later, David.