Noob question - installing roller rockers.....

[Cliff Beer]

Please excuse the "noobiness" of this question, I just have no experience with it so hoping I can get a bit of education. Essentially, I'd like to install roller rockers in my lowly Ford Racing crate engine. I believe I have the M-6007-X302 (the one on the far left.....) crate engine in my CAV. It's a good enough engine for me, and 340/310 hp/tq is plenty of power for me and my driving skills...

Crate Engines, Mustang Engines, Drag Racing Engines, Stock Car Engines, Funny Car Engins, Race Engines, Racing Engines - Ford Racing Performance Parts

This engine has the basic stamped steel non-roller rockers installed. I'd like to install a good set of roller rockers. A few questions come to mind immediately:

1. Do I need to stick with the same ratio? In other words, if she has 1.6s now, should I stick with 1.6s in a roller rocker?
2. If above is a "no" is there any real advantage to a 1.7? And does a 1.7 risk some interference?
3. Do I need roller rockers which are adjustable at the rod end so I can set the proper clearance? Or is this all done with adjustment on the pedestal "polylock"?
4. I am assuming I can get the right geometry somehow - either through adjusting the pedestal height or length of push rod.
5. Should I take out the push rods and inspect measure? Is this necessary any time new rockers go in? Are rods matched to rockers somehow, either in length or shape of the tip?
6. What is the proper clearance spec? Is it done like any MG/triumph/porsche with a cold clearance spec and a feeler gauge? Or do I adjust to zero lash, then give it one half turn as I've seen in youboob vids for hydraulic lifters?
7. Stainless or aluminum?
8. Shaft mount or pedestal?
9. Should I use stud girdles?

Thanks in advance for any help.

 

[Jon Briggs]

I have no answers to your questions. But I do have a question of my own. If you're happy with your engine, why do you want to change them?

If its not broke, don't fix it.

 

[Jac Mac]

Below within text/questions..

Please excuse the "noobiness" of this question, I just have no experience with it so hoping I can get a bit of education. Essentially, I'd like to install roller rockers in my lowly Ford Racing crate engine. I believe I have the M-6007-X302 (the one on the far left.....) crate engine in my CAV. It's a good enough engine for me, and 340/310 hp/tq is plenty of power for me and my driving skills...

Crate Engines, Mustang Engines, Drag Racing Engines, Stock Car Engines, Funny Car Engins, Race Engines, Racing Engines - Ford Racing Performance Parts

This engine has the basic stamped steel non-roller rockers installed. I'd like to install a good set of roller rockers. A few questions come to mind immediately:

1. Do I need to stick with the same ratio? In other words, if she has 1.6s now, should I stick with 1.6s in a roller rocker?For least hassle&not having to worry about valve to piston clearance
2. If above is a "no" is there any real advantage to a 1.7? And does a 1.7 risk some interference?You will need to check valve to piston clearance, you might get away with it, be aware that there are some manufacturers out in the market that also sell 1.65/1 ratio rockers that might be able to be fitted in your application with sufficient clearance
3. Do I need roller rockers which are adjustable at the rod end so I can set the proper clearance? Or is this all done with adjustment on the pedestal "polylock"?Your call, cost might be a factor, there are some sets available that are simple 'bolt on' for hydraulic cams, these can be shimmed under the pedastal if reqd to get correct geometry-along with different length pushrods if necessary.
4. I am assuming I can get the right geometry somehow - either through adjusting the pedestal height or length of push rod.yes-as above.
5. Should I take out the push rods and inspect measure? Is this necessary any time new rockers go in? Are rods matched to rockers somehow, either in length or shape of the tip?Depends on current wear of pushrod ends, preferable to use new pushrods at installation, along with check for correct length.
6. What is the proper clearance spec? Is it done like any MG/triumph/porsche with a cold clearance spec and a feeler gauge? Or do I adjust to zero lash, then give it one half turn as I've seen in youboob vids for hydraulic lifters?The 'half turn' is just a recomendationit wont really matter if its 1/4 or 3/4 of a turn as long as the lifter plunger is within its preload travel, however if you are 'heavy footed' less is better in the event you pump up a lifter with valve or lifter float, you can actually use this lifter plunger position to obtain the correct rocker geometry without changing pushrods in some cases.
7. Stainless or aluminum?Alloy should be sufficient for that camshaft
8. Shaft mount or pedestal?Pedastal should be plenty.
9. Should I use stud girdles?Overkill for this application.

Thanks in advance for any help.

 

[Howard Jones]

I have the same motor. Jac is completly correct again! That entire engine is designed around those heads and it runs out of steam at 5500.

The power increase you will get with the roller rockers will be about 20-30HP at best. You can't "feel" 25HP.

That motor will make 300Hp at the wheels with the X head and the B cam from Ford with a holley double pumper on top of a RPM performer intake. To make another 80-100 hp it's gonna take different heads and valve train. Eldenbrock RPM performer heads with the 2.02/1.60 valves and a cam with more lift and duration will get you there. Call Comp Cams tech line and ask about valve train parts and have a look at the Eldenbrock heads.

IMHO leave it alone until you decide to build another motor. If you really what to go faster put slicks on it. They ought to be good for 6-10 sec a lap. 1000 dollars worth of tires or a new 8000 dollars motor..................

 

[Steve26]

Hi Cliff,
What intake and ignition are you using? I have a similar set up with roller rockers. Let's get together and talk.

Steve

 

[Steve26]

Hi Cliff,
to answer a few of your questions:
1&2) if you have enough clearance between your valves and pistins you can go with the 1.7 rockers. What this will do is give you more lift, it would be like buying a higher lift cam! My cam is .513" lift on both intake and exhaust with a 1.6 rocker. With 1.7" rocker I think it is .544". Would have to look at the Gross lift on the cam and see what the extra .1" would do, I think it's .544"
3)Your head will determine what rocker you use. I'm using GT40X turbo swirl heads, they use pedestal type mounts and the pushrod length is very critical and not adjustable! If your heads are "stud" type mount then they are adjustable and should use the "rocker locker" type nuts.
4)I used a tool to measure the correct length pushrod and purchased them from Jegs or Summet.
5)I would replace them with new 4130 pushrods. Your choice if they are the correct length.
6)This is set by the pushrod length on the pedestal type rocker arms and is not adjustable. You could shim it if the pushrod is to long but once it's set you wont screw with it. Using the correct length pushrods I had no shimming.
7) I used aluminum, your choice. there is no right or wrong here.
8)Your heads will determine this.
9)It depends on your heads, I dont think mine has guides, I can check if you need me to. If you use guides make sure you use 4130 pushrods!

One thing to remember, the lobe center on your cam will play a role in how long your pushrod will be. Two cams with the same lift could use different length pushrods if the lobe centers are different. If you want to drop by and talk about this feel free.

Steve

 

[Jac Mac]

One thing to remember, the lobe center on your cam will play a role in how long your pushrod will be. Two cams with the same lift could use different length pushrods if the lobe centers are different. If you want to drop by and talk about this feel free.

Steve

???, the only thing that would require a change in pushrod length in this instance would be if the 'base circle' dia of the cam lobe was different, different lobe centers would not change the length required.

 

[Steve26]

Sure enough Jac, I didn't write what I thought. Base circle!

 

[Cliff Beer]

Thank you JacMac, thanks Steve, that's very helpful information. Much appreciated.

Because I didn't grow up with these engines (I grew up with alfas and MGs) I'm learning here. But, I do get the basic drill I think and the information you've shared helps a lot.

It would be interesting to know how many folks (as a percentage) are running roller rockers....just a small percent? Or, are most "built" motors running these?

I'm guessing that roller rockers don't actually add much hp/tq (5?) but do improve wear and stability in the valvetrain. Just my hunch. Related, I read an article a while back that showed that 1.7 rockers actually added very little hp/tq either, the only difference being that the 1.7 rockers moved the peak hp/tq farther up the rev range. So, all in all, not looking for a lot of performance increase here. What can I say, I have low expectations and I'm easily pleased.

 

[Cliff Beer]

Just a quick follow up question here. I'm confused (I'm confused a lot of the time.....). I have these heads on my CAV: GT-40X XTRA PERFORMANCE "TURBO-SWIRL" ALUMINUM CYLINDER HEAD | Part Details for M-6049-X302* | Ford Racing Performance Parts

At least the heads have that number cast into them. I think the above is the FRPP part number for the bare head. The head with valves is this one I believe: GT-40X XTRA PERFORMANCE “TURBO-SWIRL” ALUMINUM CYLINDER HEADS | Part Details for M-6049-X303* | Ford Racing Performance Parts

The rockers on my heads are stamped rockers which appear to be just bolted down onto a raised portion of the head with a semi-circle holder configuration. It doesn't look to me like there's any adjustment to these.

Based upon my research it seems that FRPP "bolt down" 1.6 rockers would work with these heads. I probably could use other manufacturers for this, but FRPP works fine for me.

So my question is, what FRPP 1.6 rockers am I looking for here? These? ROLLER ROCKER ARM | Part Details for M-6564-B351** | Ford Racing Performance Parts

Or something else?

Thanks again guys.....

 

[Cliff Beer]

ps. what's the difference between "bolt on" rockers, "stud mount" rockers, "screw in" rockers, or "pedestal mount" rockers? Are these all labels for the same thing?

 

[Doug S.]

Let me give this a shot, Cliff....if I'm wrong, hopefully someone else will give you the real skinny!

Do your heads have guide plates for the pushrods? If so, I think you have adjustable rockers and probably "stud mount" bolts. If not, you probably have the bolt on rockers, which are non-adjustable...hydraulic lifters and a sort of a "pedestal" on top of the bolt on which the rocker arms are located that perform the function of keeping the rocker arms aligned correctly...if you have the adjustable type rocker arms, the pushrod is kept in alignment by the guide plates and the rocker arm "indexes" off the top of the pushrod so that the end of the rocker arm that will contact the top of the valve stem is located correctly without moving out of position...if you have pedestal mount rockers the pedestal performs the indexing (alignment) function so that the end of the rocker arm that contacts the top of the valve stem is located correctly without moving out of position.

If I had to guess "stud mount" and "screw in" rockers would be synonymous, as would "bolt on" and "pedestal mount". The "bolt on" rockers are used on a "pedestal mount" stud, the "adjustable rockers" (in which it is up to you to "adjust" the lash, or clearance between the rocker tip and the tip of the valve stem) are used with guide plates and "screw in" or "stud mount" rocker mounts....those screw into the heads, whereas the pedestal mounts simply sit on the studs that are already in the heads.

Clear as mud???? Maybe I don't know what I"m talking about....it's been a long time since I built my last Cleveland. I think the presence or absence of the guide plates will be the defining characteristic.

Cheers!

Doug

 

[Steve26]

Cliff, I have the same heads they are pedestal mount.

 

[Jac Mac]

ps. what's the difference between "bolt on" rockers, "stud mount" rockers, "screw in" rockers, or "pedestal mount" rockers? Are these all labels for the same thing?

Asking for confusion here!
Factory late model SBF can have 5/16' UNC threads in head for pedestal or bolt on.
Early Factory had pressed in 3/8" studs with either adjustable 3/8" unf threads or later on 5/16' unf threads with positive stop shoulder & several grades of suitable nuts with different 'stop' shoulder height to enable correct lifter preload.
HiPo 289, B302 etc had 7/16 unc threads in head for screw-in studs with 3/8unf thread[289]/7/16unf [ B302]
Early stud mount reqd guide guide plates & hardened push rods, later had rockers with guides at valve end, no guide plates or hardened pushrods reqd.
Stud mount require rockers for that application.
Screw in usually applies to a rocker assy like Jesel where the rocker has a seperate base & trunnion kit that bolts on to the 7/16" thread of aftermarket & Hi Performance type cyl heads. thes quite often shift the point of adjustment to the push-rod cup..

Thats basically how i interpret it, I am sure the language barriers of the world will manage to confuse all of the above..

 

[Ron Earp]

Cliff, pop the valve cover and post the picture. All will be revealed. I think someone has put some stock 5L pedestal mount rockers on your heads.

Any good quality adjustable stud mount roller rocker could be used on these heads. I don't have the improved X heads, but had previous versions of the GT40 aluminum heads and used a couple of different rocker arm combinations with them.

 

[Doug S.]

Let's see if I can get some photos up, Cliff. Here's a link to a photo of a typical stamped steel rocker arm that has a pedestal mount, that's the device right next to the rocker arm. The pedestal mount goes through theslotted hole in the rocker arm and is held on with a bolt that secures the assembly to the head, which has a slotted "boss" to keep it from rotating, keeping everything aligned. Obviously one end of the rocker arm is held up by a pushrod and the other end rests on the tip of the valve stem:

https://encrypted-tbn3.gstatic.com/...ECs4yTT9ZeAkKskRTVEzOnhVRyUl_3VKp-wqmR7nxTCR2


Here's a link to a roller rocker assembly with a mount system designed to use the standard Ford pedestal boss.....eliminating the need to have the head machined and tapped for screw-in studs:

https://encrypted-tbn2.gstatic.com/...DS6f_6NvTH2k33aRv5Krb1pGqFP-GmgcNLIt7BCfmR_OA


OK, I"ll be back...on my daughter's computer and once I get a google image it kicks me off the forum, so there'll be multiple edits to finish.

Doug

 

[Cliff Beer]

Thank you gents. Very helpful information, much appreciated. I'll pop off one of the valve covers and snap a pic tomorrow and post it.

I think I'm on the right track now!