Trick Flow heads....

[blykins]

I've had a customer messaging me back and forth about using Trick Flow heads on their FE.

I've used several sets of these so far and the issue is the same:  the stand height is raised about .300" higher than a factory head.   Their included valves are longer, which helps a little, but you still end up with a net .200-.250" height difference. 

My customer decided to call Trick Flow to inquire and they told him that there is no issue as long as their valves are used. 

Guys, this is absolutely not the case and if you follow their advice, you may end up with horrible geometry with the rocker arm riding the exhaust side of the valve tip.   I know several of us have harped a lot on this, but my fear is that a lot of guys are gonna have premature valve guide wear if they don't bird-dog things on their own. 

[plovett]

Thanks.

They seem like really good heads in other respects.

paulie

[HarleyJack17]

I just wonder how or why they are ignoring the feedback.  It is one thing if a single customer says something but when builders state it, one would think Q.C. would investigate and confirm and possibly correct the issue. 

Can the area be milled on the head or does it have to be the stands that get milled?  Point being if the head can be milled, then they should correct it.  It not, then they should confess the stands will need work done.

I wonder if any of the input is making it to their engineering vs. getting sidelined by lack of follow through.  It just seems odd since an issue like this could hinder their sales, or are that may folks in the ignorance is bliss category?

[Falcon67]

Why - with the wealth of knowledge from builders that have been there/done that would a manufacturer not include known design requirements in their product.  "I know better than you other people that do the work" almost never works out.   

[blykins]

I sent them an email. 

Blair told me that he has offered input on their intake manifold and it has fallen on deaf ears.

HJ, you could do either one....the stand pads are so high on the heads that it's blatantly obvious. 

[WerbyFord]

Why are the TFS valves longer?
Is the port roof higher up?
Is the valve cover surface raised too?
Otherwise factory valve covers are going to bang into the valvetrain I'd think.

Sad that people at TFS would ignore advice from this forum's builders.

[blykins]

The ports are not raised.

The stand height is.  The stand pads are raised so high that the head bolt/stud nuts are completely under that plane. 

I imagine the valves are longer to try and aid in the stand height difference, but it's simply not enough. 

[blykins]

Geometry out of the box:

[blykins]

Geometry with some T&D street rockers, after cutting .200" off the stands.

[HarleyJack17]

Good pics. That shows the issue very well.  Why would not make the valves even longer or cut the heads correctly(preferred)?
I guess I just do not understand why they would not listen to some of the biggest names in FE building that have huge customer base(s).
That is why I asked if it "could be" done....I could partially understand it if the casting did not allow for it safely but if so , and seriously, the added cost in finishing correctly should be minimal.
They could likely save some of that cost back on less valve material 

[Falcon67]

There is an article on a FE build in Car Craft using these.  They appear clueless and sort of extroll the virtue of the raised pads.  "May require longer pushrods"

[drdano]

The ports are not raised.

The stand height and valve cover rails are. 

The valve cover rails are raised as well?  How does the valve cover actually seal correctly? 

[blykins]

The ports are not raised.

The stand height and valve cover rails are. 

The valve cover rails are raised as well?  How does the valve cover actually seal correctly?

I'll reneg on what I said until I find out for sure.  I was thinking they were because of the potential rocker arm clearance issues that you would have.  However, I don't have a set in here right now to check. 

[jayb]

I looks like somebody with no clue on rocker geometry designed those shaft mounting pads at that height.  They look to be perfectly aligned at zero lift, which of course is not where they should be.  Go figure...

[wowens]

Are the threads deeper in head for rocker shaft stand bolts ?
Increased clamping force without pulling threads ?
If not and ports not raised , makes no sense .