Some time ago I bought a freshly ground used crank, pistons, and rods off of e-bay to make a 351W into a 408. I'm finally getting around to working on it now and managed to source a free 351W. The engine I'm going to be doing this to has a stock 4bbl intake and holley carb on it.

I'm thinking that I can gasket port the intake and heads and be able to use the stockers. Also I will be grinding out the thermactor ports on the exhaust side of the heads and gasket porting them as well. Anyone here have any good websites on porting windsor heads?

Also I'm planning on rebuilding the stock carb and using it if I can. Anyone knwo what kind of CFM's this thing will flow? The engine is out of an 85 E-250. I was in at napa the other day and asked about a carb rebuild kit and they wanted $80! Anyone have a good website to buy rebuild kits from?

I know using the stock parts I'll have a lot of low end grunt, and not much top end, but that's ok by me. I'd have a grin a mile wide if I could get this thing to pull similiar to my 95 powerstroke.

Oh and while cleaning out the valve covers I removed the windage trays in them to get all the sludge out (you wouldn't imagine how much crap was under them!) Is there any real reason I should put them back in? I mean is there really an issue with the pcv system sucking oil out if that windage tray isn't in there?

Thanks for listening to my 1:30 AM ramblings. Hopefully I make sense.

 

I can tell you right now you are going to severly choke that motor with the stock intake and heads. You should fund some $$ for an intake and the other stuff you are going to need. And don't start gasket matching stuff... that's all wrong. See here..
http://www.mustangcentral.net/tech/e7.html
http://www.diyporting.com/

 

Yeah that 408 really needs to breath. You'll make lots of torque, but just make sure you match the intake cam and heads. Those stockers were made to produce torque on a 351. They are gonna suffer on the 408.

If you've waited this long to put it together don't rush and wait til you can get a good deal on intake, heads, exhaust, and carb. Look at some of the other posts to see the combos and results of other guys builds.

 

If your careful you could probably get a set of carefully ported heads to achieve these goals. Pure stock heads and intake will probably actually curtail tourqe as well as HP though. A set of GT40P heads would make a better starting point.

To get that kind of tourqe, even considering 408 cubes, you will need a long runner dual plane intake, and long tube headers, with a little bit of overlap on the cam.

If you limit engine speeds to about 5200 rpm, then a 600 cfm carb will work. At 100% volumetric effeciency means 614cfm at 5200 rpm. Estimating 85-90% volumetric effciency means about 570cfm at 5200 rpm. If you go with a higher max rpm range, then you will need a bigger carb.

 

5200 RPM! I doubt it'll ever go over 4000 RPM... I'm one of those crazy low end grunt type of guys.

I'll keep an eye out for GT40P heads, but in the meantime that site posted above for porting heads looks pretty promising to me. I might even purposely break through and then sleeve the pushrods just like that guy did.

 

http://cgi.ebay.com/ebaymotors/SBF-F...33839863QQrdZ1

Woudl those heads be any good... it says they're the precessor to the GT40 P style heads. Only thing I didn't like was the welded on stud. Hopefully if I bought them I could get it out of there and replaced.

Well I gotta get my butt to work!

 

If you want cast iron heads World Products makes good cast iron heads that won't kill the pocket book. Someone had problems with that stud (press-fit) pulling out I'd bet. Not sure if I'd mess with someone elses headache. You could maybe pull it out and have em all tapped for screw in studs but thats a small chunk of change for used stock heads.
http://www.jegs.com/webapp/wcs/store...tegoryId=10187

Now if you wanna spend a little jack and have some real nice heads ^^^^

 

i would check out the lightning forums, and find the gt40's not the gt40P's. reason is the P's require a specific manifold due to the spark plug angle

 

i find it amasing how often i see here to just get rid of stock heads. I see allot of post that they wont flow that well etc even ported. Yet i know for years in the 70s/80s lots of guys that where racing dirt track etc would port the heads out and get pretty good flow out of them, it was the option at the time since you couldnt get much aftermarket for fords. Is there some reason the newer heads cant be ported to achieve this anymore?

 

Oh.. they can be ported, and there are gains to be had. In very general terms, a ported E7 flows about the same as a stock GT-40P, and a ported GT-40P tops out in flow where many of the aftermarket heads start. A reworked stock head will be much improved, but you could be at another level again with the same money spent(on bigger valves, porting and machine work) if you instead had just bought aftermarket heads.

 

they can be ported but a maxed out stock casting won't touch a good aftermarket head.at some point the money spent on getting old heads up to snuff,valve job,new valves if needed ,valve springs and retainers ,resurfacing the head,not to mention the $'s spent on porting and you would be money AND time ahead to buy some aftermarket heads.i think you can find some iron darts that would flow plenty and wouldn't be much more than getting old stock castings in good working order.

 

Would $300 be a good price for a set of GT40P heads? I saw a set on e-bay that I think I can get for that price including the shipping. That also includes the valves, springs, and rockers... I'm sure they'll need hot tanked and checked over though.