T&D Rockers on Edelbrocks

[cjshaker]

Shouldn't he allow for compressed head gasket thickness also? I didn't see that anywhere.

[Barry_R]

Use your measurements.  My general comments are just that - general, and will change depending on your block, heads, cam base circle, etc. 

Working via the cell phone and computer today - have a sick kid at home....

[fe66comet]

I always measure push rod length on any build, stock or not. Cam base circles and possible variables even from the factories original set up like seat and valve machining can change drastically......Jon

[FirstEliminator]

     Well, I took a measurement with a 3/8 ball end push rod from an FT. It didnt' looks like it really sat in the seat too well. I did call T&D and they recommended to use a 5/16" ball with their rockers. Out of curiosity, I put some Dykem blue on the ball ends of the 3/8" push rod and put it down in the seat and twisted it a few times. Only a very thin line was marked. I found a 5/16" push rod and made a new tool. I also checked the end with the layout fluid and there was a lot more surface area contact.
   
 

   I did check all the lifters and rockers for pushrod length. The measurement with the 5/16" push rods lowest was 8.648 and the highest was 8 696. The overall average is 8.675. This was with the adjuster backed up into the rocker body.

     One turn on the T&D rocker arm adjuster seems to yeild about .050" travel.   

   T&D instructions say to measure with the adjuster one turn in from backed up all the way---this is initial position. They also say not to run with more than one turn in or out from the initial position.

 The hydraulic lifter preload is one turn. So it makes sense to back off the one turn, then you end up in the initial position.

   Now, if I buy push rods for the average of 8.675. Some rockers will have more than zero lash and require up to an extra half a turn, which would be within the specs of T&D's adjustment parameters.   Yet, other rockers will have less than zero lash, partially preloading the lifter. With these, I suspect to turn in a half turn to acheive the same amount of lifter preload across the board. This sounds like the best happy medium to me. Or, I could buy several different length push rods---which I don't really want to do.



Now, the question is, do I order push rods with through oiling or no oiling?

   thanks,
    Mark

[afret]

I think the reason T+D specifies the plus or minus from the one turn out position is to make sure the oil hole on the adjuster is in the right spot for oil to get through.  If the T+D street setup has needle bearings at the shaft, you could just cut off oil from the head and get oil from the pushrods.  You probably would get too much oil on the head if you use both sources.   

I'm not familiar with hydraulic rollers but you might look at the lifters and see where the oil source for the pushrod is on the lifter body and spin the oil pump with the lifters in the block to check the oil flow before deciding on pushrod oiling.  The solid rollers have the oil hole for the pushrods on the body away from the oil band and turned 90* from the lifter oil passage to limit the oil flow.  You get a reasonable amount of oil that way since the oil is restricted by the clearance between the lifter and lifter bore.  Crane puts a very shallow groove in the lifter body from the oil band to the pushrod oil hole and the amount of oil to the head is a bit much even with that small groove.   If the hydraulic rollers have the lifter oil hole in the lifter oil band,  you will get too much oil to the head and might have to use pushrods with restrictors so it might be better to just use the original oil passage in the head.

Here's a photo of three different FE solid rollers.  You can see the small oil hole for the pushrods just above the oil band.  The Crane lifter on the left is a different design but you should be able to see the small hole above the large oil hole and the shallow groove connecting the two that increase the oil flow a lot.

[FirstEliminator]

   I see where the variation in comes from in the need for different push rod lengths.  The valve step tips are at different heights. I'd guess that some seats are pressed in the head a little further than others. I did not remove the head to verify.  Does this variation seem normal for Edelbrock heads?

    Mark

[jayb]

I've seen variation in valve heights on lots of FE heads, but I don't know if the Edelbrock heads come like that or not.  Variations in the valve job and valve height can contribute to that issue.  With adjustable rockers its usually not a problem unless the variation is quite wide. 

[FirstEliminator]

About the oiling  to the rockers. Tonight I bolted down the intake, put in the push rods and adjusted the rockers. I put about a gallon of oil in the pan and used a drill to spin the oil pump. Well, instantly,  there was a  puddle on the floor.  Putting an oil filter on the engine seals up a big leak.   Anyway, I ran the drill  for what seemed like only a few seconds and there was oil dripping off the heads.  There was more oil on top than I've seen on previous Clevelands, Windsors and 460's. The question is, is there is too much oil going to the top?

The push rods I have are hollow and the stock top end oiling is not restricted.  The drill I used was a 1/2" air drill that turns about 400 rpms. I thought it should load the drill a bit more than it did.   

  How do I tell if there is too much oil going to the top?

     If there is too much oil, what can I do at this point to slow it down? 


   thanks,
     Mark

[jayb]

How do I tell if there is too much oil going to the top?

The only way to tell is with a clear valve cover    Seriously, is your valvetrain set up to oil through the pushrods, or through the rocker shafts like a standard FE?  If you have the T&D street rocker setup, you are oiling through the rocker shafts; the race T&D rockers oil through the pushrods.  If you are oiling through the rocker shafts, a standard restrictor arrangement for Edelbrock heads is to take a 3/16" steel  dowel about a half inch long, and drill a .070" or .080" hole through it, and then drop it into the oil feed hole under the #3 and #6 rocker shaft stands.  You can also buy these restrictors pre-made from Doug Garifo at Precision Oil Pumps.  If you are oiling through the pushrods, then you will need to restrict oil to the lifters, and that is done by accessing the plugs in the valley of the engine.  That would mean removing the intake, which it sounds like you've already installed.

You can also just run it as is, but FEs are known for putting a bunch of oil to the top of the engine, leaving very little in the pan.  So I'd recommend using the restrictors...

[FirstEliminator]

    By putting the restricters in heads, would it knock down the excess volume to the top end enough to not worry about the restricting to the lifters? 

[jayb]

I would say if you restrict the oil to the rockershafts you should be good to go.  That's what I've done on the majority of the FEs I've built.

[FirstEliminator]

    I called T&D today. Their tech suggested to completely block off the oil ports through the head if there is pushrod oiling in place.

    It will be nice to get this project done.

    Then I might be able to work on one of my own cars.

    Mark

     

[Barry_R]

If you are using the T&D street rockers we recommend a .060 restrictor pressed into the head's feed.  It'll work perfectly fine, have adequate oil, and from then on you worry about other things.  Don't worry about blocking off the lifter galley, and don't completely block off the heads please - save that approach for the race rocker stuff.

It's pretty common for a modest variation from intake to exhaust on valve tip heights - not usually enough to worry about, but it's there.  Same for spring heights - for some reason Edelbrock mills the pockets to a different depth.