i have a set of 1 3/4 prim headers for a 351 in my '69 but im not gonna get the motor built this winter. I know they will bolt up to the heads but will they hang down to low to the ground on my 302....im running a set of heads with .5" raise exhuast ports
Probably will be too low since the 351w is about an inch taller than the 302. As you deduced, the raised ports may help some though. Other things, such as the motor mount location could be a problem too. About all you can do is try it.
they'll also come together too close at the collecters, due to the 351 being wider.
(You might want to check the project car or tech pages, I think there was a picture of the underside of a project car where they did the same thing, used 351 headers on 302...I half remember seeing a picture - but I'm not sure which car or which article)
They will fit, but will not fit correctly. To point out the obvious, thats why they make different headers for 289 - 302 and another set for 351's.
Not trying to rag on you, I know how attractive it is to save a few coins. But, as hard as it is to install headers in the correct car, on the correct engine...its kind of self torture to purposely install the wrong headers.
In your situation, as a temporary measure; keep in mind that you will have to have the connection from headers to exhaust re-welded when you install the 351.
_________________ Of all the rest..."There are three faithful friends, an old wife, an old dog, and ready money..."-- Benjamin Franklin, 1738 --
<font size=-1>[ This Message was edited by: Beoweolf on 11/6/06 8:48pm ]</font>
I'm running swap headers for a 351W into a 64-65 falcon, but in my 66 mustang with 302. Heads have 3/8" raised exhaust port. I couldn't find any other headers that would give me spark plug clearance. Headers are from crites, 1 3/4" primary, 3 1/2" collector. The headers hang down low in front, but hug the floorboards too close at the collector, so I had to notch the transmission crossmember. I could have modified them a little and got a noticably better fit, but they do pretty good overall. They have slip on collectors, all the tubes are installed individually, which was pretty easy really.