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16v engine valve remanufacture


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Date: Mon, 31 Jan 2005 23:50:16 -0500

From: Rick Diogo <rick@ceostaffing.com>

Subject: 16v Head - New Valves

A colleague of mine and I have been doing some pretty extensive research on

the 16v Maserati head lately and we've come to find out that the vast

majority of the heads we've pulled apart (and certainly all of them with

any kind of real mileage on them) have some issues.

As some of you may already know, the Maserati head comes (from the factory)

with cast iron intake guides and bronze exhaust guides. Well, after

checking nearly 20 used heads (all with various hours/mileage, some were

off dyno motors from Chrysler and Roush's reliability test/facilities,

etc..) I've determined that the intake guides seem to be pretty decent

overall. However, the exhaust side is completely different. Almost

every *single* exhaust valve I've checked has had excessive guide play

(with the exception of the very low mileage heads I have or dyno heads that

have very little time on them).

In any case, approx 70-80% of the exhaust valves I have checked have been

bent. Some as much as .013" (as in the case of the head off my personal

GLHS). In fact I just pulled apart a head yesterday where the exhaust

valves ranged from .002 to .008 across the board. Now if the valve is bent

..002 or less it can typically be "cut out" when a precision valve job is

done (by a competent machinist). However anything greater than that and

you may want to consider replacing that valve or valves. And quite

honestly you should NEVER re-install a bent valve.

The problem however is two fold: Number one - where are you going to find

new replacement valves? Number two, if you are lucky enough to find some

un-bent (straight) valves, and you replace them they are sure to bend again

in a very short amount of time due to two things which we feel are

contributing factors:

First off, we feel the guide material they chose for the exhaust valves

could be substandard - we are looking into this now. Additionally (and

more importantly) we feel the quality of the alloy used in the makeup of

the valves is marginal for the type of heat these valves typically see

under boost - and this leads to thermal fatigue.

Because these valves are no longer available from Chrysler (or Maserati for

that matter) we've decided to have some new valves made in a much higher

quality material. Luckily, technology in valve material has made great

strides since 1988/1989. I am working with a company called Ferrea which

is considered one of the *world's* leading valve manufacturers. For those

of you out there who have heard of them I think it's safe to say you are

aware of their reputation in racing circles.

What we've decided to do is to have Ferrea make up new valves for not only

the exhaust but also for the intake as well. And being that the price is

the same for either making them in the stock size or in an oversize, we

have decided to make up some larger valves while we're at it.

I spoke with their lead tech today and I did bring him a complete Maserati

head about 6 months ago so he could take a very close look at its

design. We've been studying it ever since.

Bottom line, we need a minimum of 19 people to step forward and agree to

purchase a set of oversize custom valves before we can begin production. I

myself will purchase 3 sets (one for my head and two sets for the shelf)

and I know my colleague in California will buy one set, and the rest we are

looking for interested parties. So basically we need 15 more people to

step forward.

The deal is this: If we make up anywhere from 1-299 valves the cost (per

valve) is $55.00. If we make up 300 intake valves and 300 exhaust valves

(hence 19 cylinder heads) the cost drops to HALF that amount! For the

quality of the valve they would be creating this is an absolute fantastic

deal!! The only reason I am able to accomplish this is because I happen to

know someone there who is willing to give me a major price break.

I will say this: If you own a Maserati TC with a 16v head you undoubtedly

have bent valves in your cylinder head. Don't believe me? The next time

the head is off your car take it to any good machine shop and have them

chuck the valves up in the lathe and test them with a dial indicator. Once

you find out, let me know how bad they are bent. Depending on how many

miles are on the car the results will vary. I can assure you that your

exhaust valves are bent much worse than the intakes.

What does this mean? It means the car is not making *nearly* as much power

as it should (could) be. Will your engine self destruct tomorrow? Chances

are slim, but your power will certainly suffer as a result and eventually

the problem will worsen until something catastrophic occurs. The reason we

haven't seen too many failures thusfar is because the vast majority of

these cars have relatively low mileage on them. And before anyone sends me

an email saying they have a Maserati TC 16v with 100k miles on it that

still runs, keep in mind....it may still run, but put it on a dyno and let

me know how much power it's making. Or better yet.....pull the head and

check the valves for straightness. If you have even ONE exhaust valve

that's less than .004 bent I'll be absolutely astonished.

Who would benefit the most from something like this? Someone with a car

that has high mileage on it and/or someone looking to make the most power

possible out of their 16v Maserati engine.

We are looking to make both the intake and exhaust valves in a 1mm oversize

configuration. This is good for a number of reasons, but most

notably: 1) when the machine shop does the valve job they will be

grinding on a "fresh" part of the seat and this allows the valve to not

"sink" into the seat as deeply as it used to......this is good for maximum

power and efficiency. 2) the oversize valve will allow for increased

cylinder head flow, especially if you plan to have the head ported.

Can these valves be put into a head with no portwork? Absolutely.

We will have them manufactured in the stock stem size (so they will work

with your factory guides, seals, retainers, springs, and keepers)

The only thing that will be different about them will be (of course) the

head size will be 1mm larger and the composition of the valve itself

(alloys) will be completely different. They will be made to withstand

extreme EGTs (2,400degrees) and 40psi of boost (which no one on this list

or myself will probably ever see, but it's nice insurance).

I will recommend that whoever decides to get in on this group buy with us

also changes at least their exhaust guides - once again as I said due to

the fact that we believe they are made of a substandard material. Guides

can be made up pretty cheap, here again as long as we get 300 or so made

up. I can get a price on them for interested parties. And here again,

this is NOT a requirement, but something you might want to consider - I

know I'll more than likely be changing mine.

The exhaust valves will be made from a material classified as a new "Super

Alloy" and are comprised of a mixture of both Nickel and Chromium. This is

the same material used in Funny Car/Top Fuel race cars. Why go to that

extreme? Why not. It costs a little more but the additional cost is worth

it. You should never go to this length to save $5/valve by using an alloy

that can't stand the heat.

The intake valves will be made from stainless steel and will contain

Chromium, Nickel and Tungsten. Another nice thing is that we'll have them

designed with an "undercut" at the base of the stem (nearest the head) for

increased flow. This "undercut" is known as a "SuperFlo" valve. They

utilize a special roller process to reduce the stem diameter *safely* in

this area unlike some of their competitors who use a machining process in

an attempt to arrive at the smaller stem area. Ferrea has pictures of this

process in their catalog which shows (on a molecular level) how their

process is superior.

I'll close by saying this: Whoever wants to get in on this buy-in please

get in touch with me ASAP. If I don't get at least 15 people in the next

week I'll call them and let them know to go ahead with the original plan

which is to make up only three sets of these valves at the higher

price. One way or another I am getting them made up for my car. If you

want valves for your Maserati head now is the time to speak up. Just be

aware, if you choose not to get in now, and your car needs valves down the

road you will be screwed. The window of opportunity is right now.

Any questions or concerns feel free to email me directly or reply to this

email for all to see and/or discuss.

Regards,

Rick Diogo

Results Driven Inc.

1987 Shelby Charger GLHS-16v

1989 Maserati TC 16v

1990 Maserati TC 16v

1992 Dodge Spirit R/T 16v

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I am interested newly fabricated parts. I am also in need of a knowldgeable mechanic in the north San Diego county. I can be reached at dragonflyjbh@aol,com or if you prefer my phone number is 858-756-9946. I am the original owner of a 1990 TC with a 16v engine with just over 26,000 miles on it. The car looks like it was just made. It has been my obsession since I bought it.

jean b

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