[Bandit400]

Hello again guys-I have a previous thread (a few days ago) where I was asking about pushrod lengths. I seem to have found the length I like around 9.250-9.300, but the pushrod hits the body of the rocker at full lift, wanting to push the pushrod out of it's "pocket" in the rocker. I find that by shortening the pushrod, it clears, but my pattern is less than optimal. I can provice pics to show what I am describing. I have not heard of anyone having to clearance 1.7 Scorpions (it is the SB Ford PN). I am so close to the end of this project, I just want it to be done!!!!!! The previous thread with my engine specs can be found at:


http://forums.maxperformanceinc.com/...d.php?t=630719

[Bandit400]

I received a reply from a fellow board member through PM (thank you!!!) and he informed me that these arms do need to be clearanced, as they are close but not exact (due to being a SBF PN). I searched up and down but couldn't find any reference to ANYONE else having to do this. I know several people (Cliff being one I think) that runs this exact setup. Do I really have to clearance these or am I missing something big here????

[Schurkey]

Is it a rocker arm problem, or is the pushrod binding in the head casting?

Some of my 1.65 Comp Cams Magnum rockers did just what you describe until I ground the livin' beJesus out of the head (pushrod holes) and I even had to clip a little from the pushrod guideplate slot, making the slot about .070 deeper.

The pushrod holes in the heads had to be ground all the way to the bottom; not just the top inch or so.

[Bandit400]

It's been a day or two since I've been out there (sick), but I think the head clearance is ok, as it has KRE D-ports, which have been clearanced, or so I thought. What I am thinking about doing is backing the pushrod way down, and seeing if a good pattern can be established with a shorter rod. I can get it so the pushrod doesn't touch, (around the 9.1" length if I remember correctly) but the pattern gets less desireable at that length. Not terrible, but not as good as the other lengths. It's just very frustrating, as out of all the people who run this combo, I am the only one to have an issue, (or so it seemss).

[DiamondJim]

I run 1.72 Scorpions (sb ford) and apprx .620 lift w/9.4 pushrods w/o any issues. Check the pushrods for scrub marks from rubbing inside the heads. My guess is it is not the rockers. -Jim

[grandville455]

I run H.S 1.65 which are suppose to be closer to 1.72 with KRE heads no problems at .650 lift!

[ta man]

Originally Posted by grandville455

I run H.S 1.65 which are suppose to be closer to 1.72 with KRE heads no problems at .650 lift!

X2

[Bandit400]

Would pics help?

[Bandit400]

Ok I rechecked it, and it seems that the head is not binding the pushrod. I will post a pic to show what I am talking about.

[Bandit400]

Hopefully this will show what I am talking about. The one pic is at the cam's baseline, the other is full lift. WHat am I missing?

[ta man]

Originally Posted by Bandit400

Hopefully this will show what I am talking about. The one pic is at the cam's baseline, the other is full lift. WHat am I missing?

That full lift just doesn't look right at all.Those rockers seem short from fulcrum to pushrod.How far are you down the stud?

[Bandit400]

I'm not too sure how to measure that properly, but the posi-lock is 7 turns to snug it down to the rocker. I don't know if this helps. Like I said before, I can make the rod shorter and nothing touches, but then the pattern shifts too far to the intake side. It's gotta be something simple...

[DiamondJim]

Originally Posted by ta man

That full lift just doesn't look right at all.Those rockers seem short from fulcrum to pushrod.How far are you down the stud?

X2 that pis doesn't look right. Pushrod side looks real short. My 1.72 SB Ford Scorpions are silver, not sure if that means anything. Is the part number stamped on them anywhere? -Jim

[Bandit400]

The PN on the box is- SCP1020BL I searched up and down for what PN was required, and I wasn't able to find it. So I ordered for a Small Block Ford (302 etc...). Do I have the wrong arms? They say 1.72F on top of the rockers if that helps.

[Formulas]

Could be the rocker arms will not work (correctly) no matter what pushrod is used.

I bought a set of ford rockers one time and it was apparent to me that the distance from the stud to roller was alot shorter than a normal Pontiac roller arm so i sent them back.
I have another set of fords 1.72 that fit fine so i dont know what gives but from now on only real Pontiac rockers for me

I compared both fords together with my pontiac crane energizers and it proved what i suspected was true, different distance from stud to roller at the valve tip was shorter on the new ford set i bought and returned.

Hard to get a scientific measurment but about .080 - .100 you can tell with a necked eye.

[lust4speed]

Would you post another picture or two with the valve at full open. It sure looks like the pushrod would depart the rocker at anything over idle. There's usually two points where you can get a good pattern with one being way off the curve - and I think you found it.

[DiamondJim]

What studs are you using? Those look like the right rockers. -Jim

[ta man]

Originally Posted by lust4speed

Would you post another picture or two with the valve at full open. It sure looks like the pushrod would depart the rocker at anything over idle. There's usually two points where you can get a good pattern with one being way off the curve - and I think you found it.

Try a much shorter pushrod length and see what happens you will need the rocker down the stud a little farther.

[Bandit400]

Ok I went back out there today to play around. I tried a much shorter pushrod, and as expected, it did not hit the rocker. I was able to get an acceptable pattern, but it was too close to the intake side (p-rod too short). The pics I am posting here show the best "comprimise". The length is 9.050" This is the longest I can go (in .050" increments) without hitting the rocker arm. The pattern doesnt look terrible, but it is not centered on the valve tip. I know there are two schools of thought on this. One states to have a small pattern centered over the center, the other states to have the smallest regardless of where it lands on the valve. Let me know what you guys think. The pics I posted show the valve at the baseline, at full lift, the pattern I got from this, and I tried to get a pic to show where the roller was on the valve, but it came out blurrry. Sorry about the focus quality, all were taken with an iPhone. Thanks in advance, looking forward to your opinions.

[Formulas]

Get a real Pontiac rocker, been there done that, not all Ford rockers are created equal,
the roller is to close to the stud, oh just likes i said before.

i do have a pic of all 3 rockers i can send you its on my phone .. i had them lined up even with a scale near the axle to help with the visual.

but iam not sure how to post from my phone.