I have heard from a few sources (MAX_CFM is one) that when running really big cams, like Skunk2 Pro3 the LMA's need to be modified, yet no one seems to know why, or want to tell the public what needs to be done. As I want to run bigger cams than the current Toda C I have in my motor this is something that has been bothering me a bit lately. My head is a 99 ITR head so it has the best OEM LMA's already in there.

If it's a small modification like milling a bit off the plunger top or something then I do have access to a machine shop so I can get this done myself, rather than send a set halfway around the world for someone to do the job. Some info on this issue would be nice.

 

bump cuz i want to know too

 

i'd like to know what needs to be modified as well

 

im thinking maybe if you have the early model LMA's with the tapered tit rather than the flat surface you will run into binding issues with highlift cams as the rocker arm rides off the lma and binds up causing failure..

i lucked out and on my 95 gsr i had the bigger top (surface area) lma's..

i know some b16's had tapered tit lma's as well..

you cant run alot of lift with small lma's..

there was a thread on here awhile back showing this..

 

Here is a very vague write up I did a while back. You can form you own opinion from what others have said in this thread. I just did this for a visual aid. There are no solid facts in what I have presented.

https://honda-tech.com/zero...age=1

 

I've seen that thread before, thanks for posting the link, it's a good visual aid.

I inspected a 2000 Si head I have and it has the same LMA as my ITR head, mine are like the one on the right in these pics :




And here is a RLZ modified one, looks like the top is bigger in dia. Pic is borrowed from Big Teggie's for sale thread.


Another RLZ modified LMA, pic from EKhatch :


To me it looks like the top has a bigger dia. than the OEM piece, so maybe the modification they do is to mill a bit off the top, as these LMA's have a tapered edge it will not take to much to gain like 1mm extra dia. Or maybe the spring is swapped out for another one giving a higher lift capacity before binding.
I don't know though, as this is pure speculation on my part, I have no measurements or anything solid. I'm just curious, as I'd like to know before I install even bigger cams in my engine if I'm going to run into problems or not.

 

Why not just run the Prelude spring-style LMA's?

The pad on top of those are quite large.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by D-Rob &raquo;</TD></TR><TR><TD CLASS="quote">Why not just run the Prelude spring-style LMA's?

The pad on top of those are quite large.</TD></TR></TABLE>

That's what i did. Just remember to shim the LMAs with .040 thickness washers. And as for the original poster, you should be fine with ITR's LMA.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Turbo9Nut &raquo;</TD></TR><TR><TD CLASS="quote">

That's what i did. Just remember to shim the LMAs with .040 thickness washers. And as for the original poster, you should be fine with ITR's LMA.</TD></TR></TABLE>



That's what my dad did on his LSVTEC build.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by D-Rob &raquo;</TD></TR><TR><TD CLASS="quote">Why not just run the Prelude spring-style LMA's?

The pad on top of those are quite large.</TD></TR></TABLE>

that was exactly what i was gonna say . what is the incompressed height on your GSR LMA's

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by bluedlude &raquo;</TD></TR><TR><TD CLASS="quote">
</TD></TR></TABLE>

Is that a Penthouse in the background?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by D-Rob &raquo;</TD></TR><TR><TD CLASS="quote">Is that a Penthouse in the background? </TD></TR></TABLE>

the new playboy actually

 

ahh u dirty bastard...

I knew you were making some kinda special homemade sealant in that garage....eww

 

homemade Honda bond lol.....