D.Hearne said:Hard to say on the intake milling requirements. On the 5.0 I had the Canfield heads on last year, I milled the heads .060 and then needed to mill the Vic Jr intake .040 per side and .020 off the bottom to fit it. With these heads on the 331 I have now ( also a roller 5.0 block and it's had the decks milled .010 to clean them up) I used slightly thicker head gaskets ( needed to reduce the comp some) that are .009 thicker than the .039 Felpro's on the 5.0. With the same milled by .060 Canfield heads, the reproduction 3x2 intake needed no milling to fit, it did need the bolt holes ovaled slightly toward the center to line them up with the holes in the heads though. Milling the heads on a small block moves the intake bolt holes towards the center of the block slightly, hence the need to oval the intake's holes to make the bolts line up with the heads. Bottom line is even after milling, you may not need to mill the intak at all, only way to know for sure is to wait til you have the heads back on and torqued in place, then set the intake down and see how everything lines up before milling the intake. You might just need thinner intake gaskets after miliing the heads to make everything line up. Ford's recommendation on head milling is that you can mill the heads up to .040 before needing to mill the intake.
D.Hearne said:Can't tell on the comp ratio increase, it's impossible to figure with your heads. If you can reduce the head volume by 4 cc's then that will raise it back up to 9.0 to 1 . Milling an E7TE head .040 will reduce the chamber volume 6 cc's, milling your's the same amount, will reduce the volume by a lesser amount, due to the smaller chamber size. You could possibly get a 4 cc reduction with a .040 mill. That combined with thinner gaskets could get it closer to where it needs to be. A cam swap might be easier though. According to Comp Cams, the 260 and 268H will work with your comp ratio.
D.Hearne said:As for those who still insist he needs a bigger carb, that's not the case. If it's a dog from off idle, then a larger carb will do nothing to help. Even with a too small carb, the motor would be responsive ( if the motor is set up and tuned correctly) from off idle to what ever rpm the carb would run out of breathe at. From what Crushnut says, it's a dog from the get go, so the carb size isn't the problem. Like I posted before, my 331 stroker with a 3x2 Holley intake and carbs, is a terror off the line , even just using the primary carb, and that's only 250 cfm's worth of carb.
I don't disagree with anything you say, just that those who think his carb being too small is the problem are barking up the wrong tree. As you and I have posted, even with a too small carb it will still be responsive off the line and up to a certain rpm where it will run short of breathe. I think he needs to work with what he's got before swapping carbs. And I also agree on the cam swap over milling the heads, but he needs to make sure that the cam and/or the compression is the problem before changing or altering parts.mdjay said:While I don't disagree with what you're saying may be a concern, crush posted that he pretty much just bolted it on. So checking the operation of the current carb is critical. The choke could be malfuctioning, the secondaries could not be kicking in, tiny jets, the springs on the metering rods could be too big and not openning, the float could be stuck or misadjusted, squirter pump etc. So check it!
However, it's been my experience that with Ford motors, they do not like to be leaned out. Like you said, they may come off the line ok, if it's functioning properly, but they will run out of air/gas at about 3000-4k rpms. A stocker runs real nice with a Holley 600. A mild performance motor should be running a 600-650 carb. I have a close friend that runs two 500's on an edel dual quad intake, 302 with a large cam, and it runs clean and very strong.
As I said, the cam selection concerns me but I still think it wouldn't run quite that bad. I also don't think it would run that bad with just the 500 unless something was wrong with the operation of the carb. Or it has small jets and large metering rods. So check it! But ulitmately, change it. I have found the demons to be superior.
http://www.barrygrant.com/demon/default.aspx?page=5
I agree to a possible change for the cam. Don't mill the heads. But first I would test and adjust the current carb, and highly consider testing a bigger carb. The recommendations for your intake are here:
http://www.holley.com/HiOctn/ProdLine/Products/AMS/AMSM/8020.html
Crush, starting at 600 cfm, it should come off the line strong with a very responsive bottom and middle end. Gradually moving up to 650, you will gradually loose the bottom end and gain on the top end. So depending on the cam you end up with, even current, move the size of the carb up. You selected a nice intake that's good to 6800 rpms. Give it the air/gas it wants!
Yeah, what he said!D.Hearne said:I don't disagree with anything you say, just that those who think his carb being too small is the problem are barking up the wrong tree. As you and I have posted, even with a too small carb it will still be responsive off the line and up to a certain rpm where it will run short of breathe. I think he needs to work with what he's got before swapping carbs. And I also agree on the cam swap over milling the heads, but he needs to make sure that the cam and/or the compression is the problem before changing or altering parts.
How's things in P'Cola ? Have they rebuilt the I-10 bridge across the bay yet ? Better yet did they find the truck driver that dissappeared off it ? Also heard that on of the tunnels in Mobile was either damaged or flooded in the storm, that true ?ratio411 said:Yeah, what he said!
That is what I just posted, more or less...
Tune what ya got, down to the last detail, and find the problem before you change stuff.
Dave
ratio411 said:RV cams need less compression, not more.
That is not his issue.
Dave
rbohm said:more lift will help on the top end as well, and the comp cams he268h high energy cam does this nicely. the lobe centers are 110 degrees, and the valve overlap is something like 50 degrees. a tad large, but will help the engine at all rpm ranges. with a thinner head gasket, he can bump the compression to around 8.8 or 8.9:1, and that will also help.