Hello All,

I recently upgraded the top end on my L48 with Brodix heads, new cam w/flat tappet lifters and 1.6 roller rockers. The car is running great but I took off valve covers to check valve lash and I found that a couple of the rockers are not sitting properly on the valves. I noticed during initial install that the roller was shitfed over a bit and not centered left to right on the valve. The off center is more obvious now and I'm concerned that it will fail if I run it this way. I really cant move the rods to allow the roller to move left and center on the valve becuase the valve guide that came with the heads won't allow the push rod and movement at all right to left. I've added some pics below so I hope you can point me in the right direction.


TIA

 

Something is definitely up and it looks like a few of your rollers may need replacement already. Are your push rods riding against your rod guides? In theory, they should not actually ride against the guides, they can touch, but should not be riding with pressure against the guides. Seems your guides are pushing the rods in a weird direction. Perhaps the wrong guides have been used or they are installed incorrectly?

Not much help I am afraid, but yes do not run it like this. The alignment needs to be corrected.

 

Did you install the guideplates and rocker studs or did they come that way fully assembled from Brodix?

-Let's theoretically say that your guide plates when unbolted could be slightly scooted so that the intake's pushrod is closer to the port wall and the rocker is straighter -do you even have the clearance between the pushrod and that part of the head to slightly scoot it over and improve it?

I had a similar issue with my Profiler heads and I was able to loosen the rocker studs and move the guideplate a bit to make it significantly better.
Adjustable guideplates also help IF you actually have the pushrod to wall clearance -if not you need to open up more clearance but the wall between the pushrod and the intake runner can get thin and breaking through would be terrible.
-I know one builder who presses and offsets the trunion in the rocker body with a full "true" roller-rockers, but with your pressed roller-tipped rockers that's not an option.

Offset true roller rockers for the intakes are a really good solution but probably the most expensive option...

-There is one company that makes a weldless adjustable guideplate for SBCs but I can't find them right now to save my life...
[Edit] Of course, it's Jomar. Not cheap, but you don't have to weld them... https://www.competitionproducts.com/...tinfo/JOM1501/


Adam

 

The situation in your photos is NOT ok to just run... Quite terrible..

Does that valve guide in the upper left of your top-most photo have a crack in it or is that a hair on it or something??


Adam

 

Call Brodix and ask them if you need a split guide plate for these.....or a "60/40" guide plate.

Jebby

 

Most the rocker companies make .050" offset rocker sets for this reason. You get standard exhaust rockers, but then the push rod cup is moved to the left .050" for 4 intake rockers and to the right .050" for the other 4 intake rockers.

Scorpion / Johnson's offset SBC rockers even list common heads that need the offset, BUT they list Dart Pro1 heads (basically all of them), Dart Iron Eagle (basically all of them), Dart SHP 180-220cc and Brodix Track1 -but only big intake port volume heads. They also lift AFR 227, 235, and 245 heads needing the .050" offset.

The weird thing is that they list Brodix Track1, but don't mention Brodix IK heads needing the offset rockers, so that gives me some pause...
Like Jebbysan says, call Brodix. -But if they say "do nothing, it's fine", they clearly haven't seen your 3rd picture above...

Adam

 

Why should this happen at all? This must be about some dimensional failure / out of tolerance manufacturing. I will not pretend to know much about engine building, but the geometry / dimensions of all of this stuff should be very easy to manufacture accurately. Its just basic math. Maybe somebody can explain why pieces of metal cannot be built and manufactured to exactly where it needs to be. Its not rocket science, and in todays world of cad / software design,......something as simply as this should be dead on.

 

You do not need an offset rocker with the correct guide plate spacing....a split guide plate will fix this quick....it is pretty common on aftermarket heads.....usually you can slot the stock guide plate and get what you need but this has a hell of an offset on the intake for an IK head.....
But....the split guide plates are a pain to work with.....after spacing, they really need to be removed and tack welded.

Jebby

 

It is very common for the guide center on an aftermarket small block head to be scooted over .050-.100 to give pushrod clearance at the outside of the intake runner......but this one is a head scratcher, and I have worked with IK heads before.

Jebby

 

Are any other rockers showing the same wear?

 

Yes please don't run anymore 'til corrected and call Brodix (and send pics). Pretty sure their entry level smallest runner head shouldn't need split guide plates and definitely not an offset rocker, this head must have missed the bus going to the QC department.

 

Maybe its not the guide plates.
Maybe its not the pushrods.
Maybe its not the rockers.
Maybe it IS the rocker ***** / jam-nuts.

What's the story on the rockers purchase? Everything bought separately? Hodge-podge, mis-match?
It appears the rocker ball is allowing the rocker to tilt laterally.

 

I removed the guides plates and I can line up the pushrods and rockers perfectly without having the pushrods touch the heads. Can I get the guide plates and shave enough off the inside to allow the pushrod to take the correct angle? The guide plats have no play to shift when stub is installed but I could also drill out the stud hole to allow for some play?

You can see the pushrod is not touching head but rockers is straight back.

 

What do the pushrods look like? Torqued off of true, they must have been rubbing quite a bit on the guides, no?

 

You will not make your current guide plates work….short of cutting them in half. If you slot them….when you scoot it over, both will move and the exhaust will be wrong too.
You need split guide plates or the correct spacing….assuming Brodix has something that will work.
But it is 100% the guide plates….

Jebby

 

Called Brodix and they said that it's not a head issue it's a problem with the CC guide that they included in the heads and I should call Comp cams which is crap because they came with the heads. I guess I'll have to I'll take a look at what guide plates are available and order one to test out. The guide plates that came with the heads are comp cams 4808.

 

Not an expert on guide plates but did look up that number 4808.
It seems those are the "flat style" meaning the slot is closer to the head than others.
The closer to the head, the less the guide can control the lateral movement of the pushrod (physics).

If those were mine, I think I would pitch them and get the "raised guide plates". That's what came on my aluminum aftermarket heads.
The slot is an half inch higher, closer to the rocker and making any movement of the pushrod nill.

You could try Summit, under valvetrain parts, SBC, and see what they have in a raised guide.

 

I ordered raised guide plates from Jegs to see if they make a difference.

https://www.jegs.com/i/JEGS/555/202001/10002/-1

Will update once I try them.

 

Jebby have you used the 3 piece Jomar adjustable guide plates that don't require welding?

I avoided the split guide plates and went with a set of Comp's stepped guideplates because I didn't want to deal with having to weld them together. Had I known that the Jomar 3 piece ones existed at the time, I probably would've bought them instead.
https://www.competitionproducts.com/...tinfo/JOM1501/

Adam

 

Those aren't adjustable...
How are they different than what you currently have other than the raised "step"?

The "split" guideplates that Jebby is recommending to you have elongated rocker stud slots and allow you to move the intake valve slightly independently of the exhaust to get them both to where they're supposed to be.
After your torque them down into place (without them moving all around while tightening them), my understanding is you're supposed to tack weld them together so they can't move again.




Adam