Performance Boats Forum banner

1 - 20 of 54 Posts

·
senior member
Joined
·
1,814 Posts
Discussion Starter #1
i installed the t&d's according to the instructions & that did not work. the valve stems are too long. the heads have a raised port & that put the rocker on the outside edge of the valve. i had to (not shim) the assembly in order to get the rocker onto the center of the valve stem. this caused the geometry of the pushrod to look kind-of screwed. the exaust pushrod is 16* off of being 90* . & the intake @ 19* off from being 90*. the stud mounted rocker came in A angle but it had a deep pocket to recieve it at any steep angle. the t&d's dont. it looks like it is wrong. & i am thinking of taking this back off. here are some pics.I need some good opinions from experienced builders. my opinion is that this set-up sucks for my heads & i want my $$ back..i know t&d's are supposed to be real good but for this application? thanks in advance
 

Attachments

·
Registered
Joined
·
6,278 Posts
i installed the t&d's according to the instructions & that did not work. the valve stems are too long. the heads have a raised port & that put the rocker on the outside edge of the valve. i had to (not shim) the assembly in order to get the rocker onto the center of the valve stem. this caused the geometry of the pushrod to look kind-of screwed. the exaust pushrod is 16* off of being 90* . & the intake @ 19* off from being 90*. the stud mounted rocker came in A angle but it had a deep pocket to recieve it at any steep angle. the t&d's dont. it looks like it is wrong. & i am thinking of taking this back off. here are some pics.I need some good opinions from experienced builders. my opinion is that this set-up sucks for my heads & i want my $$ back..i know t&d's are supposed to be real good but for this application? thanks in advance
What brand of heads are those? It appears that as you have said, with that long of valve that there is a geometry problem and those rockers may not work for you. With the correct length of pushrod your going to run off the edge of the valve. Steelcomp would be the man to talk to about this. He's dealt with simular issues on here before. I believe he went to a set of ford rocker arms to cure it.
 

·
Registered
Joined
·
939 Posts
geometry

Did you set it up with adjustable pushrods, and then order the length you need?

On my Brodix heads with T&D, it takes three different lengths.

Jerry
 

·
Administrator
Joined
·
16,877 Posts
Did you disassemble a rocker, remove a spring and use the gage from the shaft to the valve stem?

There shouldnt be a problem if you shimmed them using that method.
 

·
steelcomp was here
Joined
·
26,515 Posts
I'm not following your first post completely.
First, what heds are they?
Second, when you say the rockers are off 16*/19* from 90*, do you mean at mid lift? What part of the rocker are you referring to for this angle?
To recap: The imaginary line that passes through the center of the trunnion and center of the roller tip needs to be at 90* to the valve at mid lift.
It's a mistake to try to get the roller tip centered on the valve as a means of establishing proper geometry. With extra long valves the pattern will typically be on the outer 1/3 of the valve. Any more than that, to me, is not acceptable.
Those look like Brodix conventional heads, so if you have the right part number from T&D they should fit.

This comment makes no sense to me at all:

the stud mounted rocker came in A angle but it had a deep pocket to recieve it at any steep angle. the t&d's dont.
 

·
Some guy
Joined
·
3,616 Posts
I am currently setting up a new set of T&D's on a new set of Brodix BB 4 xtra heads. You didn't state whether you used the gauge that T&D supplies with the set, but it's critical to getting geometry correct with them. Pushrod length is merely a function of the diameter of the cam and final height of the rocker.

That being said, the set I am working on needed to lower the exhaust stands about .055", due to using some Ferrea super alloy valves that come in only a few lengths. They were about that much shorter than the "stock" Brodix valves, but necessary for this engine since it will be turbo charged. The owner and I chose to have that much removed from the heads, but it could have come off the bottom of the rocker stands to give the same results. The intake stands will need a couple of shims, but needed to have a little machining to allow the stands to sit flush onto the head.

I elected not to pull a rocker apart,, didn't want to hurt one of the tiny snap rings, but instead measured the shaft diameter and used a substitute .625" diameter shaft to measure height. *** Note that T&D also gives instructions that the checker tool needs to be adjusted according to cam lift ***
 

·
Registered
Joined
·
19 Posts
I noticed in your second pic that there is quite an angle on the push rod to the rocker seat. If this is what you are talking about you will have to get radius end (for the rocker end only) push rods. Some push rod manufacturers will ask if you are using shaft rockers.
Most of the time if you change rocker types on any engine it will require different push rods.

Fred
 

·
Premium Member
Joined
·
25,975 Posts
It's a mistake to try to get the roller tip centered on the valve as a means of establishing proper geometry.
Steel, I swear, this is by far and away the biggest misconception in setting up rocker geometery. This one misconception is probably responsible for more poorly set up rockers than any one single thing. Who ever came up with line of BS should be kicked in the nutz.

As long as the roller isn't in jeopardy of riding off the edge of the valve, stop worrying about the rollers location on the valve tip. It will only lead down a path of bad geometry trying to get that one useless thing lined up. If you chase that, you can't help but blow it where it really counts.

Try putting it back the way they sent it to you, with the roller off center, and check you rocker geometry again.

On some heads, with long enough valves, the only way the roller can be in the center of the valve stem is if they actually relocate the rocker back towards the intake manifold. Crower, in their stud rockers does just that in a effort to get the roller back on center. But its was a waste of time and money. Being off center on the top of a 11/32 valve amount squat in side load.
Raising or lowering the rocker to relocate the roller is a HUGE mistake. The location of the roller IS NOT play into proper geometry. EVER.
The spring is what causes guide wear, not the location of the roller pushing on the valve. The heavier the spring, the faster the wear. The spring side loads the valve, not the roller.



100% free webcam site! | Awesome chicks and it is absolutely free! | Watch free live sex cam - easy as 1-2-3
 

·
Registered
Joined
·
633 Posts
Paul
Read andFollow the instructions !! what Barry (Obnoxious 001) and Ron (infomaniac) are saying is correct . you may have to shim or machine off some material off the head .

Also if you are using Lash caps that extra hight has to be figured in .

the gage supplied with the rockers is for .750 lift , so whatever your cam is >follow the instructions .

Mine work fine , on Brodix 2-extras ... Eric :)hand
 

·
AKA Blownjet 468
Joined
·
1,205 Posts
the last set of Brodix heads I did ended up having to shim up the stands quite a bit,
due to a smaller cam, and longer valves- the shims were not cheap from T&D either!

you can kinda see in the picture that the stands are shimmed up quie a bit- but these are the
cheaper type T&D's with the individual stands..... prevous settup was .700+ lift with a stock length
valve- now setup for 650 lift with .100 long valves......ignore the date, this was 09:p
 

Attachments

·
senior member
Joined
·
1,814 Posts
Discussion Starter #12
Did you set it up with adjustable pushrods, and then order the length you need?

On my Brodix heads with T&D, it takes three different lengths.

Jerry
?three?where would the third size go?&yes,i cut a pushrod & slid fuel line over it to the right lenght & then measured it
 

·
senior member
Joined
·
1,814 Posts
Discussion Starter #13
What brand of heads are those? It appears that as you have said, with that long of valve that there is a geometry problem and those rockers may not work for you. With the correct length of pushrod your going to run off the edge of the valve. Steelcomp would be the man to talk to about this. He's dealt with simular issues on here before. I believe he went to a set of ford rocker arms to cure it.
brodex bb2 extras
 

·
senior member
Joined
·
1,814 Posts
Discussion Starter #14
Did you disassemble a rocker, remove a spring and use the gage from the shaft to the valve stem?

There shouldnt be a problem if you shimmed them using that method.
yes & it was too far out to the outside of the stem. the machine shop thought it looked better without the shims as far as the roller on the valve stem goes. t& d said the big chiefs have a pretty steep angle for the push rod also. so as long as it goes in i shoukld be fine.
 

·
senior member
Joined
·
1,814 Posts
Discussion Starter #15 (Edited)
QUOTE=steelcomp;1417355]I'm not following your first post completely.
First, what heds are they?
Second, when you say the rockers are off 16*/19* from 90*, do you mean at mid lift? What part of the rocker are you referring to for this angle?
To recap: The imaginary line that passes through the center of the trunnion and center of the roller tip needs to be at 90* to the valve at mid lift.
It's a mistake to try to get the roller tip centered on the valve as a means of establishing proper geometry. With extra long valves the pattern will typically be on the outer 1/3 of the valve. Any more than that, to me, is not acceptable.
Those look like Brodix conventional heads, so if you have the right part number from T&D they should fit.

This comment makes no sense to me at all:[/QUOTE] brodex bb2 extra,check the pic.for the 16* & 19* i was talking about.it wasn't an "A" angle ,it was a typo ,not at mid lift just sitting .never set -up head nor did i know anything but I was led to believe it was pretty simple. i guess on a regualar head. P1000154-2.jpg [
 

·
senior member
Joined
·
1,814 Posts
Discussion Starter #16
what happens if i run them like this ? does it put pressur on the rocker & cause them to break or something?
 

·
Administrator
Joined
·
16,877 Posts
That's what I suspected. You are worried about the angle of the pushrod going into the rocker.

You should be looking at the angle formed between the roller trunion centerline to the tip roller centerline as compared to the valve.

but if you checked them with the gage provided by T&D, don't worry about the angle the pushrod comes in at. As long as it clears everything.
 

·
senior member
Joined
·
1,814 Posts
Discussion Starter #18
That's what I suspected. You are worried about the angle of the pushrod going into the rocker.

You should be looking at the angle formed between the roller trunion centerline to the tip roller centerline as compared to the valve.

but if you checked them with the gage provided by T&D, don't worry about the angle the pushrod comes in at. As long as it clears everything.
i was told to throw that gauge away
 

·
Premium Member
Joined
·
25,975 Posts
http://www.performanceboats.com/attachment.php?attachmentid=117143&d=1306295782&thumb=1

That's what I suspected. You are worried about the angle of the pushrod going into the rocker.

You should be looking at the angle formed between the roller trunion centerline to the tip roller centerline as compared to the valve.

but if you checked them with the gage provided by T&D, don't worry about the angle the pushrod comes in at. As long as it clears everything.
Listen to him Turbo. You way off base with that angle. It means ziltch.
Between that angle concern, and worrying about where the roller tip is on the valve, your headed towards disaster.



100% free webcam site! | Awesome chicks and it is absolutely free! | Watch free live sex cam - easy as 1-2-3
 
1 - 20 of 54 Posts
Top