Replacing rocker arms. Other than the arms, do I need anything else?

69 Mach I · #1 (**permalink**) 06-29-2005, 02:35 AM

I currently have some Crane rocker arms, part number 36800. These are 1.6 ratio arms for a 3/8 screw in stud. I want to put some full roller rockers in there. I am thinking about the Comp. Cams pro magnum rocker arms, part number 1331, also 1.6 ratio for 3/8 screw in stud. I know I need taller valve covers to accomodate the rocker arms and am prepared to order the 3.75 inch Ford Racing chromed aluminum valve covers, part number 6582-R302 as well. Do I need anything else? Also, would you use a stud girdle on screw-in studs or only for the pedestal mounts?

trularin · #2 (**permalink**) 06-29-2005, 05:13 AM

Taller covers with baffles. Make sure you get covers with baffles. I suggest you get a clear picture of what you are doing with the PCV and/or venting system. Open breathers spray oil all over the engine and car.

How many RPMs are your turning? A stud girdle is good for high spring rate, long travel, high RPM use and unless you are turning in the 7500 or more range with something like a D221, I would look at putting your money into a few other areas.

Just my opinion.

69 Mach I · #3 (**permalink**) 06-29-2005, 05:52 AM

Quote:

[i]Originally posted by trularin

Taller covers with baffles. Make sure you get covers with baffles. I suggest you get a clear picture of what you are doing with the PCV and/or venting system.

How many RPMs are your turning? A stud girdle is good for high spring rate, long travel, high RPM use and unless you are turning in the 7500 or more range with something like a D221, I would look at putting your money into a few other areas.

the FR covers are baffled. I don't turn past 6300 RPMs and that is only at the end of the 1/4. The springs are stock from the Edelbrock RPM Performers. I do have a pretty decent sized hydraulic cam at

ADV DUR: INT 297, EXH 308
LIFT: INT 538, EXH 534
DURATION AT .50 DEGREES: INT 236, EXH 242 @ 108 centerline

but Edelbrock tells me that the springs can take that much lift with no problem.

BTW, I used to live in Farmington Hills before moving here. Still go back every November for deer season

trularin · #4 (**permalink**) 06-29-2005, 11:04 AM

My wife is from Farmington Hills.

Leave the girdle off.

Dave Bermani · #5 (**permalink**) 06-29-2005, 01:50 PM

I'm running Comp roller rockers too. I recommend using stud girdles. I had a 3/8 stud snap last December. The stud girdle held the rocker more or less in place so nothing was damaged other than the stud. I went to 7/16 studs which required new rockers, but now I'm not worried. I have a roller cam and the valve springs are very heavy. You'll have to buy new poly locks to use the girdles.

Dave

69 Mach I · #6 (**permalink**) 06-29-2005, 02:37 PM

Quote:

Originally posted by Dave Bermani

I'm running Comp roller rockers too. I recommend using stud girdles. I had a 3/8 stud snap last December. The stud girdle held the rocker more or less in place so nothing was damaged other than the stud. I went to 7/16 studs which required new rockers, but now I'm not worried. I have a roller cam and the valve springs are very heavy. You'll have to buy new poly locks to use the girdles.

Dave

Yeah, but you have a 427 with a roller cam. I only have a 362 with a hydraulic flat tappit cam which is a decent sized cam but nothing wild. I should have 400 hp at the fly max. Given that my build is hot and not wild, would I really need a girdle?