What is you guys' take on milling heads? Is an angle mill better than a flat mill or vice versa? I'm thinking about decking my heads to get me to 9.5:1 or 9.8:1. I'm just not sure what all of the pros and cons are of each milling process. I realize that I'm gonna have to get my intake milled as well and possibly new pushrods.

Oh, I'm running World Windsor Sr. heads incase you need to know.

Thanks in advance for your input.

 

Just flat mill them, why complicate things ? Once you've milled the heads, bolt em in place with gaskets, torque them, then set the intake down in place with gaskets. Measure the gap under the intake ends. Also check the fit at the heads. Then see if the bolts will start in the holes. Only then, do you make a determination as to whether or not the intake needs milling. Some will, some won't. I milled a set of Canfield heads .060. I had to mill the intake I first used with em, a Vic Jr. Next intake with em was a repop 3x2 Ford intake. It needed no milling, but the bolt holes in the intake needed to be "wallered out" towards the center of the intake to match the holes moved inward by the milling job on the heads. I did a 400M with milled by .010 deck block and .030 on the heads and it too, needed no milling on the intake to fit. Also wait till the heads are torqued down to check pushrod fit (rocker geometry) You may there too just need off the shelf parts as far as pushrods.

 

Well, the reason that I am even considering an angle mill is because I talked to a local machinist who said about it. From what I gathered through all of the loud noise at the track, you can supposedly get better performance (flow into the cylinders) from an angle mill because it brings your valves pretty much perpendicular to the piston instead of at a slight angle. I don't know, I'm still kind of researching the idea. I figured that I could get some good input here like I always do.

I follow you on the intake fitting bit. I am not a machinist so I will not be performing any of the machining process. I will let all of the fitting stuff up to the pros.

I am optimistically hoping that I wont have to buy new pushrods. The rods that I have in it now are still basically new.

Do you think I will notice a significant performance gain if I bump the compression up to 9.5 or 9.8 from 9:1?

 

Bringing the valves closer to perpendicular to the piston, doesn't sound to me like the way to improve flow. Just the opposite if you ask me. The whole reason a Hemi head breathes so much better is due to the valve's being angled more than a wedge head in relation to the piston/bore centerline. I'd find another machinist.

 

If an angle mill produces any gain at all you'll need a dyno to see it. That's fine when a couple more HP means the difference between 1st and 2nd, but you'll never notice it on the street.
You have much better than stock heads, what does the rest of this motor consist of? Do you have enough cam to take advantage of all the potential head flow? What intake and fuel system is on it? What's the displacement?

 

No I'm not worried about a couple HP. I was just curious about the two types of mill. Apparently Dave Jenson recommends angle mill. I guess an advantage of an angle mill would be that instead of milling the intake for fittment issures, they are milling the intake side of the head. That way you do not have to keep the heads and intake as a set.

No, I don't think that I have enough cam to get the most out of these heads. The motor is a 351W +.040. Edelbrock Air Gap intake, Road Demon 625 carb, MSD 6al, MSD pro billet, 1 1/2" long tube headers. The cam that I am running was designed by Cam Research. He said that it would work well with my combination and application, which it does pretty decent. He "Scott" also told me that more compression would help out considerably, which is why I'm going to have my heads decked. I'm only running about 9:1 right now. I want to go to about 9.8:1. All that I burn in it is high test (93) gas any way. (Obviously not a daily driver) My cam specs are 200,205 @50 266,270 Adv and 440,440 lift. I needed a bottom end cam for my application, at least at this point. I'm starting to dabble with truck pulling. There are one or two guys that beat me last time by 1 and 2 feet. I have to be able to make that up some where! I'm afraid that the visous cycle of wanting more and more and more is starting to begin.

 

Oh, and no the truck is not strickty for truck pullin. I use it for cutting wood, towing trailers, and hauling whatever else. It's kind of a do all at this point.

 

http://victorylibrary.com/mopar/intake-mill-c.htm


Pete

 

Yeah that is basically what I was told aside from all of the calculations and measurements. Makes perfect sense. It justs sucks that the angle mill is 4X the price of a flat. I guess that there probably would be alot of setup involved in an angle mill. I'll have to decide what I want to do and possibly save up some more money.

Thanks Pete

 

More compression will certainly boost TQ and HP, but you're leaving a lot more on the table with that cam, IMO. The heads increase airflow right upto and beyond 1/2" lift, so there's no reason not to take advantage of it. There are plenty cams available off the shelf with durations equal to or shorter even than what you have, with 0.530" lift or more.

 

I thought the same thing about the cam when Cam Research spec'd it out. But I asked him about it as far as the heads were concerned and he said that it would work good with my heads. I remembered Hemi and someone else, maybe you Paul, saying about getting full potential out of heads which is why I questioned the cam. But they are the professionals and since they only build cams and such for ford V-8's I figured that they knew what they were doing. Keep in mind that I'm not unhappy with the cam. I just want a little bit more out of my build. I told Cam Research that my normal operating range was from idle to 4000 RPM and that I sometimes pull up to 10K and haul up to 4K. He basically designed me the cam for that purpose. My peak torque is at 3400 rpm and peak HP is at 4600 rpm.

The last cam that I had in the motor was a 493/500 lift and 262/270 Adv. 218/224 @.50. The cam research cam does perform a little better but not what I expected it to do. Maybe my expectations are too high.

What profile would you recommend?

 

I saw you HP ad TQ peaks and thought.. WOW that's high up in rpm.. then remembered this is a carb'd motor. The rpm range you are using is much better suited to a tuned port EFI setup. The long runner OEM style intakes have TQ curves that are nearly flat from 2000rpm up, probably 100lb/ft more TQ down there compared to a carb intake. That is a lot of change of course.. but it's the only way to make a big difference within your powerband short of strapping a blower on it. On a carb'd motor relatively small cam changes don't make hugh differences, the shape of the power curve doesn't change much, just moves up and down the tach following the cam duration.

 

I see what your're saying. I guess I just want my peaks a little taller if ya know what I mean. But then again, how do you know when you have enough HP and TQ? I don't know, maybe I never will. (LOL) More than likely either my wife or my wallet will let me know I guess. I think I can swing the head work though. Definately not able to stroke it YET..........!
Thanks Paul

 

You never mentioned what type of cam you are running? And what is the rocker ratio? Go with a HYDR-Roller cam and 1.7 roller rockers you will see a big differance without hurting your bottom end power. Your killing your engines potential with that small cam. Go with a Ford Racing or a Crane cam and use conical springs and set your valve lass at maxium 1/4 turn past zero and no more than 36 total degrees timing. You have everything to make it run but the small cam is killing it. Good luck. Ron

 

The cam that I'm running is a custom grind from Cam Research. The specs are 200/205 @.050, 266/270 adv, and 440/440 lift. Scott at cam research designed the cam for my application.
As far as the roller cam, I don't have a roller block, YET.
The rockers that I have are crane energizer 1.6 ratio full rollers.