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I want to stick a 351W in the '66 Coupe and retain the stock hood, but am unclear whether I'll have hood clearance problems. I just completed a dimensional analysis, and found the 2.5" clearance I have now (with the 289) will be eaten up with a 351W conversion, using an Edelbrock Performer RPM 351W intake.

Please let me know if you had any hood clearance problems, or had to swap out the stock hood for an aftermarket hood. If you did, what aftermarket hood did you use?
 

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I can't comment on the hood, but one of the best tips I've seen for putting a 351W in 65-66's, is to use a Monte Carlo bar. The reason is that over time, the shock towers have leaned in from years of use. Using the bar, returns the towers to their original locations, giving you a little extra room around the manifolds/headers.
 

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Thanks. I've installed a Monte Carlo bar already. It's the hood that concerns me. I know some VMF'ers have done this swap! HELP!!!
 

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We did this swap back about ten years ago. Using a Holley Street Dominator intake and a Weiand Fre-Flo open element low-profile air cleaner (one of the triangle shaped ones) we just barely cleared the hood, but it was too close. So we installed a scoop. As far as exhaust goes you are going to need to order some headers. We first installed the engine with stock manifolds; but they were wedged against the shock towers. It was like having solid motor mounts. We later ordered some custom headers and they went in with no clearance problems.
 

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I've heard, but cannot confirm, that using '66 motor mounts will help a 351w sit a little lower than the '65s......but as your car is a '66 maybe that's not any help.

Might also talk to the guy who goes by "mustangsteve" - IIRC this is a swap he's done multiple times.

Let us know how it goes - I want to do it myself with my '66 coupe. Thanks - Dickson
 

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Ditch the Performer RPM manifold and use a Performer manifold; carbureator mount sits lower with the Performer with improved streetability (torque). I was talked into trying the Performer RPM for increased horsepower with my 351W; not true and caused hood clearence problems. I changed it back and have an almost new 351W Performer RPM, in box, sitting in storage. I do use a 1/2" carb spacer for best overall power.

Also find the thinist air cleaner possible and carefull with the air cleaner hold down screw/bolt going through your hood.

For general information I am running a Holly 600cfm, F303 roller cam (.512" in & ex), Twisted wedge heads (2.02" in & 1.6?" out), roller rockers, JBA shorties, 11" clutch and toploader with 3.25:1 rear gears. I keep rev limit to 5,800 rpm but it will pull very strong to 6,800 rpm.

PS, the JBA headers in two years have not created an exhaust gasket leaks nor loose header bolts. I think it is because of the thicker header flanges.
 

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I'm running a 351W in a '65 with the stock hood and a Performer RPM intake. It *can* be done, but it's really tight. I used a ball of aluminum foil to gauge clearance, and there basically isn't any. I'm also using a 3" K&N filter, and that certainly isn't helping anything. The Edelbrock Proflo (triangular) leaves more room, but I like the big K&N. The Proflo also flows air primarily from the top (instead of the sides like a conventional cleaner), and since I had very little room I was afraid I wasn't getting enough air. I can hear the top of the air cleaner chattering against the hood (it is wearing the paint away on the underside of the hood, but hasn't yet dented the hood...), and I plan on eventually either putting on a scoop or going to an aftermarket cowl induction type hood. Bottom line is it can be done, but if it fits your budget plan on going ahead with a hood modification/change. If you go with the later style motor mounts (67? I forget...), and use a drop-base air cleaner with a thin filter you might be okay. Forget a carb spacer if you're running an RPM intake with the stock hood (not that you need one with the RPM intake anyway...). Good luck whatever you decide /forums/images/icons/smile.gif

Shane
 

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Well, I have mine in a 70, so I cant realy help you much. But I did have a problem with a 351w, tourker II man, 1" spacer, and a 4" hi air filter./forums/images/icons/smile.gif [BTW, a cheep source for a 14" 4" high air filter. Look one up for an old 80's GM desel car. Perfict.]
 
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would you be interested in trading or selling the rpm manifold? if so send me a private message. my windsor doesnt want to rev all that well but it has plenty of torque. it will start out of third gear without any problems or lugging at all.
as far as hood clearance i have a shelby scoop on mine. i have a 1 inch spacer though. they are kind of expensive but i got a 2 inch tall KN air filter with an extreme top. it allows me to use a small air cleaner and still have plenty of flow.
 
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