ws6rufus

iTrader: (6)

I have a set of MTI stageII heads that have around 10K on them and all the exhaust valves and some of the intake valves are spent. The stems are worn enough so that you can feel a step in them when you rub your fingers on them.
What do you think caused this.
The valves are Ferrea 2.055 and 1.60.
Are the Manley valves any better or worse
Thanks

Eric

Crazyquik

Hmm, are they the Extreme Duty Ferrea valves or the regular ones? That seems very odd.

ws6rufus

iTrader: (6)

The intakes are part# F6234P and exhaust# F6233P

Im getting new valves are the Manleys any better?

What should the stem to guide clearence be when I get the new valves?

ws6rufus

iTrader: (6)

ttt

Nine Ball

iTrader: (38)

WS6Rufus, I'll see if I can get Jayson from MTI to reply here for ya.

Tony

ws6rufus

iTrader: (6)

Thanks Tony

ws6rufus

iTrader: (6)

Just so Im not mis-understood I am in no way complaining about the quaility of the heads. The port work is beautiful.

I bought them used for a really good deal and after replacing the valves and a valve job Ill basically have a new set of Stage II heads for substantially less than a new pair.

I just want to make sure it doesnt happen again.

The heads are milled .030 and the previous owner used rocker arm shims with stock length pushrods.
Do you think the shims could have thrown the valve geometry off enough to cause the valves to not be aligned correctly in the guide?

Or could there have been an oiling problem?

Valves that Ive seen like this before (where there is a step you can actually feel when you rub your finger on the line between the stem that is in the guide and the part that is like new because it never goes into the guide) have generally been on high mileage heads.

Maybe the person I bought them off of lied about the mileage but they were bought new in june 2000 so how many miles can be put on in 17 months?

thanks
Eric

Thanks

<img src="images/icons/confused.gif" border="0">

MTI

First let me say that I highly do not recommend changing to a different type valve. The 6000 series Ferrea valve is an outstanding performance street/strip valve. Do you know exactly how much shim was being used under the rockers? If it was more than .030" then the rockers would have too much slack in them and would be hitting the top of the valves too hard.

I recommend you have the guides checked, valve job the heads and lap in a fresh set of 6000 series Ferrea valves. Coat the tops of the valves with oil or assembly lube before re-installing the rockers with a .030" shim underneath.

Good luck!

ws6rufus

iTrader: (6)

Thanks Alot Jason

The shims were .035 thick

Im going to use shorter pushrods with no shims

What is proper valve to guide clearence for these heads?

Eric

nitropickup

Using shorter pushrods w/o shims WILL result in excessive noise. All MTI heads are Surface cut .030 unless requested otherwise. All cut heads need rocker shims for proper valvetrain geometry. I know you feel your LS1 is a bit more advanced then an old Ford, but they've been doing it like that for years. The designer of the LS1 head definately had very heavy Ford influences.

ws6rufus

iTrader: (6)

nitropickup:
I dont understand why using shorter pushrods istead of shims will cause excessive valvetrain noise? Does it really matter if you make up the 0.030 by shortening the pushrod vs raising the rocker arm?

Eric

ChrisB

If a shorter pushrod causes noise because the pushrod is "too short" (to little preload) then shimming the rockers would only exacerbate this problem. (with the same length pushrod).

If the pushrod is to short then you need a longer pushrod; simple as that.

I personally do not think shimming the rockers is a good idea at all, and would do all valvetrain adjustments with pushrod length, and then valve length if more adjustability was required.

Shimming the rockers can also cause increased rocker tip/valve angularity, and this could definitely contribute to worn valvue guides.

As to the problem it sounds like a case of bad geometry (due to whoever installed the setup, not MTI) and/or a case of oil starvation to the heads.

I would also echo "MTI" and suggest you stick with the same type of valves. It sounds like you also need a valve job also (if you replace valves at a minimum they need to be lapped). Though people send this type of work off to any local machine shop typically I would highly suggest you send this to a an experienced head porter (since MTI did your heads they would be a good choice)- the valve job is actually a very critical part of the overall package.

Chris

ws6rufus

iTrader: (6)

I was going to use 7.350" pushrods with the 0.030 milled heads.
Technically (I think?) these pushrods will have 0.020 less preload than stock.
Is this going to be a problem?

laZy

[quote]As to the problem it sounds like a case of bad geometry (due to whoever installed the setup, not MTI <img src="images/icons/rolleyes.gif" border="0"> ) and/or a case of oil starvation to the heads. <hr></blockquote>The setup was completely of MTI's design, they gave me the shims w/the heads as well as the pushrods. Oil starvation is a possiblity since I had a major oil consumption problem, I had to check the oil level once a week but was usually on top of it. And I didn't lie to you about the mileage Eric. The heads went on at 26k and the car was flooded w/30.5k, less than 5k.

ws6rufus

iTrader: (6)

Hi Lawrence:

I in no way was inferring that you lied to me.
Just as I told you on the phone I am very happy with the deal.

Just so everyone knows!!!

Lawrence aka laZy is a great guy to business with.
I did an fairly high dollar deal with him from 2000 miles away and he was very honest and helpful.
As stated earlier in the post He gave me a good enough deal so that even after I put the new valves and get a valve job I will basically have a new set of heads for substantially less than a new set.

You must have had a oiling and or a geometry problem because almost all valve stems are worn really bad.
I just want to make sure It gets fixed and does not happen to me when I put them on my car.

Thanks

Eric


<img src="images/icons/wink.gif" border="0">

laZy

[quote]Originally posted by ws6rufus:
<strong>
Maybe the person I bought them off of lied about the mileage

I in no way was inferring that you lied to me.
( <img src="images/icons/confused.gif" border="0"> )

You must have had a oiling and or a geometry problem because almost all valve stems are worn really bad.
I just want to make sure It gets fixed and does not happen to me when I put them on my car.

Thanks

Eric


<img src="images/icons/wink.gif" border="0"> </strong><hr></blockquote>I figured that MTI knew what they were doing with the shims and pushrod length, but I guess I was wrong. Oh well, live and learn. I was in the process of trying to remedy the oil problem when I lost the car, unfortunately I didn't have the chance to figure out what was causing it. Would have been interesting to known so such things could be prevented in the future. It was my guess though that oil was seeping past the rocker arm bolts into the intake runners.

Lawrence

[ November 15, 2001: Message edited by: laZy ]</p>

racer7088

Chris B.,

""I personally do not think shimming the rockers is a good idea at all, and would do all valvetrain adjustments with pushrod length, and then valve length if more adjustability was required.

Shimming the rockers can also cause increased rocker tip/valve angularity, and this could definitely contribute to worn valvue guides.""

Why do you think this?

msce2b-dustin

ttt


So what was the conclusion on this??? .030 heads....go with shorter rods or shims???

I was under the impression that the shorter rods were the way to go.

pontiaddict

[quote] It was my guess though that oil was seeping past the rocker arm bolts into the intake runners.
Lawrence

<hr></blockquote>Thats good stuff. I never thought about that,and it makes alot of sense. Pretty sure Ill be pulling the rocker bolts out and putting some sealer on them. Thanks