Newbie, help with 20V turbo build

[RedMist]

Excellent post Fivebob. Opened my eyes in regards to forgings and metalurgy.

[Mr Revhead]

whered you get your phd again?

Hypereutectic pistons usually have 16-24% silicon content and are either produced as a casting, like Mercedes Benz truck pistons, or are hot forged like the Toyota items

so let me get this straight... Hypereutectic describes the compisition, not the manufactoring process? Hypereutectic can be either cast or forged?
so the 4agze pistons are Hypereutectic forged items? thats the 6 million dollar question!

anyone no a metalurgilist? (spelling ) i can probably arrange for some new pistons to analyze...

[vvega]

Ahh the bullsh*t is strong in this thread

so true but you didnt really fix that did you

Note all alloys are cast, whether it be into billets, or their final shape, so use of this term doesn’t imply the final finishing process in this case

number one not all alloy is cast

one word.....
extrusion

extruded alloy is not cast

Forging, casting and sintering all processes, hypereutectic refers to the composition of the material, specifically the concentration of a minor component in this case silicon.

ive already said that its there high silicon content i just made it simple

NB 6000 series alloys are not used for pistons as vvega stated and certainly not in the T89 temper which involves cold working (hard to do on a finished item), they are not Hypereutectic and usually have less 1.5% silicon in them, the main alloying element in 6000 series is magnesium (to form magnesium silicate) and it’s not suitable for pistons, 6061 is the most common of the high strength 6000 series. Both 4032 and 6061 are typically hot die forged and 6061 can be cold forged.

you are correct that was my bad
4000 series is the grade wanted for cars



thogh i do have reservations on your understanding of cold working

Cold working
Metals can be forced into new shapes at room temperature by cold working. There are a number of methods including:
cold rolling
the metal strip is passed between two rolls that have only a narrow gap between them

drawing
the metal is pulled through a small hole in a die

deep drawing
a punch forces the metal sheet into a die. This is the process used to make seamless tubes and some cans (sometimes cans are formed from a flat sheet and welded)
pressing a metal sheet is pressed onto a shaped die or mould to form an intricate shape such as a car body panel

Work Hardening
Cold working produces additional dislocations within the metal structure. When two or more dislocations meet, the movement of one tends to interfere with the movement of the other. The more dislocations there are, the more they will hinder each other's movement.
Initially the dislocations produced by cold working can move through the metal structure and the shape of the material will change. As the working continues, however, the movement of the dislocations becomes more difficult. This increases the strength of the metal and also makes it stiffer. Therefore it becomes less malleable and ductile. That is, it is more difficult to change its shape. We say that the metal has become work hardened.


but this has no impact on a machined part



referance:
standard aviation maintenance handbook
jeppeson publishing

If you can find a manufacturer that forges 4032 pistons these are probably the best ones to use in a forced induction engine, especially a street driven one, they don’t have the expansion problems of 2618, and are not as brittle as hypereutectic pistons, so they don’t exhibit the common Toyota problem of broken ring lands as readily

Die Forged:
An alloy slug close to the final outside diameter is pre-heated in an air-circulating furnace to a temperature quite close to the operating temperature of the
piston crown when the engine is operating at full power. The forging press then presses it into a die. After forging, any excess material is removed and
the forgings are then tempered.
Die forged alloys: There are two common alloys used in forged pistons. 2618A aluminum alloy is the most commonly used material. The quality of this is
enhanced depending on what sort of tempering has been applied.
Normally, T6, which can increase the strength of the alloy by as much as 30%. This is, in my opinion, the lowest acceptable quality to use in a vehicle
using modern fuels.
2618-alloy pistons keep their shape under extreme pressures and high rpm's.
4032 - High silicon-aluminum alloys such as this have great wear characteristics because the silicon particulate hardens the alloy and reduces the thermal
coefficient of expansion. However, they can turn brittle and become prone to catastrophic failure fracturing when a crack starts.
Low- or no-silicon alloys, such as 2618, may wear a bit faster but provide better strength and durability.
In the rare case of a crack in a 2618 piston, the crack will migrate to an area of lower stress and stop.

http://perso.wanadoo.fr/laverdamania/pistongb.htm



http://www.burnsstainless.com/TechArtic ... ticle.html

some info on alloys

T89 temper which involves cold working (hard to do on a finished item

http://www.burnsstainless.com/TechArtic ... ticle.html

to help you understand how alloy is tempered



everything i do is to a mil spec and is one of the highest standereds in the world



if you wish to have a discussion about this where i can give you access to one of the largest referance libarys on alloys in new zealand come down to work

maybe then youll lose the attatuide

v


[/quote]

[vvega]

anyone no a metalurgilist? (spelling ) i can probably arrange for some new pistons to analyze...

send them to pacific airospace corp
hamilton airport

att wayne
cell 75


we have a lab set up just for that


v

[Mr Revhead]

vvega

you state earlier that hyperutectic is a process of making a piston... or at least speak of it as such

hyperutectic pistons can handle simalar condidtions as forged pistons

ie it can be cast, forged or hyperutectic

yet it seems evidence has been presented that its actually to do with the material.. which is it?

while these posts are making very interesting reading, the issue at hand here is the construction of the pistons and all evidence points to forged, even some you have presented

Note how the forging has a smooth eggshell finish and the casting has ribs and lines

from http://perso.wanadoo.fr/laverdamania/pistongb.htm

if you look on the underside of the gze piston you can clearly see the forging pattern.

i just ask the two of you to remember the question at hand! its some thing many of us really what to get to the bottom of.

with reguards to the piston test, maybe an independant tester would be a better way of settling this debate?
ill see what i can arrange

[vvega]

im tring to make it so others can understand rather than tring to baffle them


im not interested in arugements
and the fact is you cant really prove anything on or in reference to the net so it is a pointless exercise

its hard to say without getting an proper analasis done on how the piston is formed

but the point of the whole disscussion was about wethier they are forged

Piston types:
Die cast:
- This process requires the melting of a high silicon alloy in an electric furnace to around 700 C.
The molten alloy is then poured into a multi-piece cast iron die and allowed to solidify slowly; producing a very accurately shaped piston casting.
After the casting has cooled; they are tempered to improve its qualities.
There is a sub-class of cast pistons that are poured in an inert gas environment so as to give fewer impurities and so are less inclined to start cracking.
Most modern Japanese bike OEM pistons are made this way.
There is another sub-class of cast piston called hypereutectic. This is a high silicate cast piston.
The result is a light cast piston having nearly the strength as a forged piston combined with the desired hardness and low expansion rates of a typical
cast piston. Hypereutectic aluminum has 15% less thermal expansion than conventional piston alloys. Hypereutectic pistons are a low-cost alternative
to forged pistons for certain original equipment engine applications requiring something better than an ordinary cast piston.
I don't think they are available in bike pistons.
Die casting alloys: A 10% silicon aluminum alloy F132 is normally used.
The hypereutectic uses a higher silicon alloy called 390.
Die Forged:
An alloy slug close to the final outside diameter is pre-heated in an air-circulating furnace to a temperature quite close to the operating temperature of the
piston crown when the engine is operating at full power. The forging press then presses it into a die. After forging, any excess material is removed and
the forgings are then tempered.
Die forged alloys: There are two common alloys used in forged pistons. 2618A aluminum alloy is the most commonly used material. The quality of this is
enhanced depending on what sort of tempering has been applied.
Normally, T6, which can increase the strength of the alloy by as much as 30%. This is, in my opinion, the lowest acceptable quality to use in a vehicle
using modern fuels.


taken from the above link

i think forging then would be to expensive for a mass prodution sence

v

[fivebob]

so let me get this straight... Hypereutectic describes the compisition, not the manufactoring process? Hypereutectic can be either cast or forged?
so the 4agze pistons are Hypereutectic forged items? thats the 6 million dollar question!

Yes they can be forged, cast or sintered. Judging by the pics posted in the link to the club4ag discussion, from the flow and structure structure of the grains it appears to be forged not pressure die cast, which is the other method of manufacture commonly used.

Also there have been many discussions in the past ten years that I have seen because people used the misnomer "Semi-Forged" rather than the correct term of semi-solid forged, while most of these ended in flame wars all these discussions I can recall ended up with the conclusion that they were definitely not cast, so that really only leaves one viable alternative doesn't it.

I have SAE papers that describe the process of Thixo-forming (semi-solid forging) hypereutectic pistons and it's adoption by several major Japanese manufacturers (surprise, surprise) so it's more than likely they are forged in this manner, probably from A390 Alloy. Also, though no relevant to this discussion, I have just found papers on the use of powdered metal technolgies (sintered) and their possible adoption for automotive use, about bloody time too, AFAIK the Russians have been making the stuff for military use since the late seventies.

[vvega]

What is the difference between a forged piston and a cast piston?
A cast piston is liquid molten aluminum poured or injected into a mold. A forged piston is made from a solid ingot and pressed or extruded into shape before machining.


Forging is a manufacturing process where metal is pressed, pounded or squeezed under great pressure into high strength parts known as forgings. This is usually done by heating the metal, but some forgings are produced without heating.

Generally, forged components are shaped by either a hammer or a press. Forging on the hammer is carried out in a succession of die impressions using repeated blows. In a press, the component is usually hit only once in each die impression.

The Forging Process

The three basic types of aluminum alloy forgings are: open-die forgings, closed-die forgings, and rolled rings.

In open die forging, the work component is not completely confined as it is being shaped by the dies. This process is commonly associated with large parts such as shafts, sleeves, and disks, but the part’s weight can range from 5 to 500,000 lbs.

Most open die forgings are produced on flat sides. Round swaging dies and V dies are also used in pairs or with a flat die.

As the forging workpiece is hammered or pressed, it is repeatedly manipulated between the dies until it reaches final forged dimensions. Because the process is inexact and requires a skilled forging operator, substantial workpiece stock allowances are retained to accommodate forging irregularities. The forged part is rough machined and then finished machined to final dimensions.

In open die forging, metals are worked above their recrystallization temperatures. Since the process requires repeated changes in workpiece positioning, the workpiece cools during open die forging below its hot-working or recrystallization temperature. It then must be reheated before forging can continue.

Impression die forging is the most basic example of impression die forging and accounts for the majority of forging production. In impression die forging, two dies are brought together and the workpiece undergoes plastic deformation until its enlarged sides touch the die side walls.

Some material flows outside the die impression, forming flash. The flash cools rapidly and presents increased resistance to deformation, effectively becoming part of the tool. This builds pressure inside the bulk of the workpiece, aiding material flow into unfilled impressions.

Ring rolling has evolved from an art into a strictly controlled engineering process. In the ring rolling process, a preform is heated to forging temperature and placed over the internal roll of the rolling machine. Pressure is applied to the wall by the main roll as the ring rotates. The cross-sectional area is reduced as the inner and outer diameters are expanded.

Rings can be rolled into numerous sizes, ranging from rollerbearing sleeves to rings of 25 ft in diameter with face heights of more than 80 in.

[fivebob]

Ahh the bullsh*t is strong in this thread

so true but you didnt really fix that did you

I think I did a pretty good job but I'll leave that for others to decide

extruded alloy is not cast

No, but the billet from which it is extruded is though. My reference was to the production of the billet of alloy that a piston is forged from, so taken out of context I was not correct in stating that all alloys are cast (at some stage of their lifetime), and my post even included reference to one type that wasn't cast i.e. sintered.

ive already said that its there high silicon content i just made it simple

Simple maybe, but misleading and hardly adequate for people to fully understand the term. My post may not have been such a simple definition, however I believe it was accurate, and all the technical terms were explained in such a manner as to be understandable to someone not versed in the subject. If I failed then please let me know the terms you didn't understand and I will endeavour to explain them more fully for you.

you are correct that was my bad
4000 series is the grade wanted for cars

Ahh a back flip of gymnastic proportions, pity you didn't land on the mat and missed the part where I stated that 4032 was not considered Hypereutectic, which is what your original post implied 6000 (now 4000) series alloys were. Care to change your answer to A390 or one of the other Hypereutectic alloys?

thogh i do have reservations on your understanding of cold working
...
to help you understand how alloy is tempered

Thanks, but I already have a good understanding of the processes involved. Though for the enlightenment of others reading this thread could you please explain how a piston forged from 4032 would be treated to T89 temper? I'd do it myself, but I don't have the necessary documention readily available.

if you wish to have a discussion about this where i can give you access to one of the largest referance libarys on alloys in new zealand come down to work

Please use that vast reference library in future before posting and you won't have to do so many back flips when someone points out the truth. I suggest you start with a little poetry.

maybe then youll lose the attatuide

Sorry, but I'm not impressed by what people do for a living or how important they think it makes them. Among my friends and acquaintances I number some who were rocket scientists working for NASA, others who are professors of Automotive and Mechanical Engineering at very prestigious universities, even some theorectical mathematicians and nuclear physicists, all of them are very down to earth and realise that even they can, and do, make simple honest mistakes, they do however not try and BS when they don’t know the answer, and certainly don’t try and cover up when they get it wrong.

BTW I only have an attitude to BS, I have no problem with rational discussion and debate, nor people who honestly believe what they are saying without resorting to the old adage of “If you can’t dazzle them with brilliance, baffle them with bullsh*t”. I too realise that I don’t know it all (though sometimes in may not appear that way) and I’m quite willing to be corrected when I can be proven wrong. You however seem to take great offence at the suggestion that you may not know all you think you do, and would do well to remember that this is only the internet, where it's neither necessary, nor indeed sometimes desirable, to contribute your knowledge or lack thereof. Which reminds me there’s another thread here that’s needs some inaccuracies corrected, but I’ll save that to a later date when I have the appropriate texts to hand

PS Nice to see from you last posts that you are actually doing some research, though plagarism is not something I condone, so perhaps a reference to the page were you got your info from would be the courteous thing to do in future.

[vvega]

Five bob
tri to keep to the topic mate

im not intrested in argueing
if you want to rubish me feel free to do so but i dont really give a $&#$% unless you wanna do it in person

her is some more info ON THE TOPIC not on some litle personal problem

Speed-Pro

Pistons


There are several factors to consider when selecting pistons for a high performance application. Choices are made through comparison of cost, design, material, and compression ratio. The relative importance of these features is dictated by the intended use of the engine. The requirements for a Saturday night boulevard cruiser are not the same as those of a dedicated race vehicle. Isolating each of these characteristics will help establish some guidelines for proper piston selection. The single most important question an engine builder must answer is: "What will this engine be used for?" This is a case where the racer has an advantage, because they know the conditions that their vehicle will operate under, the fuel they will be using and modifications are often limited by sanctioning body rules. The street oriented enthusiast must consider the quality of the fuel available, the level of performance expected of the vehicle and the possibility of future additions such as nitrous oxide systems, turbos, or superchargers. Any modification that increases the potential for detonation must be carefully considered before making a selection.




Piston Material and Manufacturing Process Selection

top
Hypereutectic

Federal-Mogul utilizes two manufacturing processes for the production of high performance pistons: Speed-Pro Hypereutectic pistons are cast in permanent molds, while Speed-Pro POWERFORGED pistons are extruded from aluminum bar stock. Each has advantages in certain applications, but there are cases where the choice is not an easy one. An honest evaluation of your needs will yield the most satisfactory results.

Speed-Pro’s cast hypereutectic material is a relative newcomer to the performance market, and has several attractive features. Our hypereutectic pistons operate perfectly with standard ring end gaps and have conventional ring land locations. When compared to traditional cast pistons, which are not designed for performance use, the hypereutectics are significantly stronger, particularly in the highly loaded ring land, skirt and pin bore areas. Our FM244 Alloy contains 16.5 percent silicon and has excellent tensile and fatigue strength. This material’s improved thermal characteristics, its greater hardness and the increased resistance to scuffing permit tight bore clearances which help minimize noise on cold engine start up. This quiet operation, along with a lower cost are the primary advantages over a comparable forged piston. These pistons are an excellent choice for street performance, “claimer” oval track engines and bracket racing use. They will also work well in moderate supercharged applications and are suitable for towing and marine use.

POWERFORGED

Speed-Pro POWERFORGED pistons set the standard for the performance industry, with material and design superiority that has been proven in every form of racing. The forging process has inherent advantages in terms of density, ultimate strength and durability. Forging eliminates porosity in the metal, improves ductility and will allow the piston to run cooler than a comparable cast unit. POWERFORGED pistons start from a “near net shape” forging, with a desirable horizontal grain flow and tightly controlled head thickness. This minimizes piston weight without compromising strength. These pistons are better able to withstand the high cylinder pressures and skirt loads imposed by racing use and are more likely to survive limited detonation and valve piston contact which may occur during a race. If your vehicle is to be used for endurance racing, faster classes of drag racing or extreme duty street performance, you should probably select a forged piston. Engines with very high compression ratios (11:1 and over), high boost superchargers, nitrous oxide or which operate under conditions approaching detonation will benefit from the POWERFORGED piston’s characteristics.

Our unique VMS-75 alloy is used in our most popular POWERFORGED pistons. This alloy contains approximately 11 percent silicon for long life and scuff resistance – and is ideal for both street use and racing applications. Extreme performance applications will benefit from our new line of pistons manufactured with aerospace quality 2618 alloy, which has even greater high temperature strength than our traditional alloys. The 2618 does not contain any silicon, though – so it is more susceptible to scuffing and wear if not run with adequate clearance. Pistons made from 2618 alloy are not recommended for street use.

While horsepower benefits are often claimed by those favoring one piston material over another, it is best to make your choice based on intended application and use, not on theoretical power improvements. We supply many variations -- choose the one that best meets your needs.

Design Criteria
top


Both the Hypereutectic and the POWERFORGED pistons are available in a variety of configurations to meet the needs of an engine builder. The areas which get the most attention are head design, compression ratio, skirt strength, weight and pin retention method.

Piston Head Design

Piston head design is dictated by the desired compression ratio, the shape and volume of the cylinder head used and by the desired number, size and location of valve reliefs. Pistons with four equal sized valve reliefs are usually designed to work in all cylinders of an engine, while still allowing a built in pin offset. A piston which has two different sized valve reliefs can be used only in half the cylinders of engines having siamesed valve arrangements, such as the small block Chevrolet. Such combinations require two piston part numbers, dedicated to specific cylinders in the engine. Engines such as the big block Chevrolet, which alternate the intake and exhaust valves across the head, can use a single two relief piston part number for the entire engine if pins are not offset.

A dome on a piston is considered detrimental to flame travel and airflow within the cylinder, but is often the only way to achieve a desired compression ratio when using large volume heads. A flat top piston with a smaller chamber volume is generally more desirable. Several race engine builders have gone to a reverse dome configuration, where the piston top mirrors the combustion chamber.

Our line of CNC machined pistons utilize the latest in machining equipment technology to generate dome profiles with outstanding dimensional and volume accuracy. These pistons are ideal for race applications, delivering extremely consistent compression ratios and weight, and reducing the need for extensive machine shop work.

Some domed pistons can be modified into a flat top, to lower compression ratio, but this is not a job for the home engine builder. A minimum head thickness of .180" for forgings, or .220" for hypereutectics must be maintained, with greater thickness required for endurance, nitrous, or blower use. Many pistons cannot be modified – if you are not sure, contact Federal-Mogul Technical Service! These same cautions apply to valve relief modification.

Piston to Valve and Cylinder Head Clearances

Piston to valve clearance should be a minimum of .100". This clearance will be changed if heads or block have been machined and must be checked at assembly. While some people claim to “get away” with less clearance, there are many others that have bent valves and broken engines trying to do so. When using steel rods, the minimum clearance between the piston and the cylinder head should be around .040", aluminum rods require an additional .010 – .020" due to their tendency to stretch at higher engine speeds. Many engines use a flat “quench” area on the piston, which creates beneficial turbulence within the combustion chamber by coming into close contact with the bottom of the cylinder head. In applications having this “quench” design the clearance between the piston and the head should not exceed .060" in this area, or destructive detonation may occur. This is the reason that stacking head gaskets to lower the compression ratio usually delivers poor results.


http://www.federal-mogul.com/cda/content/front/0,2194,2442_2905_6800,00.html


[/url]

[fivebob]

i think forging then would be to expensive for a mass prodution sence

Not so, it's actually more expensive to cast than to forge Hypereutectic alloys. I won't bore you with long irrelevant quotes from commercial sources but the following should be enough to convince those with an open minds that in all probability this is how Toyota Pistons are made.

An SAE paper on thixoforming (semi solid forging) of aluminium master cylinders http://www.delphi.com/pdf/techpapers/2000-01-0060.pdf from the conclusion it's obvious that this technology is cheaper and produces a better product than die casting.

Significant advantages were achieved by using an aluminum SSM forging in place of the traditional permanent mold casting. These include the improved dimensional control capability, which makes possible a reduction in mass and final machining, the capability with SSM to forge what were previously machined features, and laminar flow of semi-solid material in die-fill, which results in lower porosity than liquid casting processes. Together with lower tooling costs, made possible with higher cycle rates and the need for fewer part cavities, the final result is lower cost than in the permanent mold process.

From 'The Auminium Car', The Auminium Extruders Assoc., 1995 the reason why Die Cast Hypereutectic alloys are not cost effective.

Hypereutectic alloys contain 16 to 23% silicon. In these the first phase to solidify, the primary phase, is silicon. These alloys tend to have a distribution of coarse silicon particles which provide excellent wear resistance. Aluminium alloy 390 containing 17% silicon was originally developed for engine block applications, but is currently used in applications requiring excellent wear resistance such as pistons and pulleys. Many of the components manufactured in this alloy are die cast, but porosity is a frequent problem. A further problem is that this alloy has a high latent heat and a wide melting range, and requires a high melt temperature 700 - 760oC. This leads to short die lives and the long solidification time makes it difficult to avoid segregation of the silicon particles.

I have plenty of other such papers at my disposal, but I cant be bothered typing them in so I trust that is enough credible information to lay this topic to rest. I’m sure the vast majority of readers know where the truth lies so I’ll bid this topic adieu and once again leave it to the X-Spurts, otherwise referred to as unknown drips under pressure

PS vvega, where's that explanation of T89 tempering of 4032 forged pistons, surely you know the answer, or perhaps not...

[Mr Revhead]

my head hurts.
but i can see clearly now the bs is gone.....

thanks guys learned lots. and confimed lots. now just have to try and remember it all.....

[vvega]

fivebob send me some alloypistons and ill happly precep them up for too what ever your heart desires

ps t89 is a misprint on my behalf there is no such temper
but hey if you kknew anything about tempering you would have picked this up


we heat treat a fair bit of the components we use at work
normally 6061 and 2023
five bob the fact is i do this for a living you do not
that is the end of it
if you advice to heat teat alloys im happy to talk saltbaths soak time temps and quench times and quench water temps or perhaps you want to get into precep temps and times for artifical aging
but ffs
give up
i work to a millitary spec so i really have no choice in procedures that we use

like i said
you have quite honestly shown to me and any other person who dose work with alloy you have no idea what cold working is or even how heat treatment is done

i have no doubt that google will help you with you endevours to show how much others know about the subject but thats not you

time to put up or shut up fivebob
come see me at work ill happy to give you a reall close look at a potassium salt bath

best of luck

v

[NZ_AE86]

Would you like a bowl of milk with that??

[vvega]

lol @ NZ_AE86
v

[Bazda]

well from my experience my 4agze engine with 8.0:1 pistons arent forged.

from the last melt down i had ages ago now, a bit of the piston broke off where then i coudl clearly see the material inside and accoring to many people in the motorsport scene said they werent forged!! this pissed me off i thought i had forged pistons damnit!!
But still some people say they are some say they arent.

I dont know the real story i jsut go buy what i've been told.
And considering how cheap they are when u buy them from toyota......

[RedMist]

Bazda, you need to read a thread before replying.

VVega, Fivebob has "put up", I suggest instead of making personal attacks you attempt to dissuade others that the merits of his posts are worthless.... your most certainly not doing that at the moment. In fact your personal attacks are doing nothing but strengthening his case.

In regards to "five bob the fact is i do this for a living you do not
that is the end of it" I fail to see your reasoning. Does the fact that you do something for a living make you better at it than anyone else? Again if your argument is weak, and your taken to task by a layman what does that say about your job skill?

[vvega]

omg boeing better stop flying planes
cause there all gunna fall out of the skys

im not saying his posts are worthless
in fact most of the info is spot on

redmist
i you knew the job i did you would understand that
i do it for a living is more than enough
but hey who am i to tell the great fivebob that hes wrong about things so obvious to some of us

i got a alloy series wrong wow that must make me a evil person but at the end of the day we all make mistakes

as for the personal attacks
i attempted to move on with my back to the topic coment
but unfortunatly some of us cant just get along

v

[Mr Revhead]

for those of you who dont feel like reading the above thesis....

ALL FACTORY 4AGZE PISTONS ARE FORGED

[Al]

hay guys, yeah i tried search and i couldnt find much info, sorry if its already been talked about a million times.
i havnt had much experience with toyotas before, im usually with the mazdas but im trying to build a project car for a mate of mine.

we have a 4AGZE engine to start with, going to turbo it, but i am wanting to use a head off the 20 valve engine.
anyone got advice for this, are the cam gears the same? so if i swap the head will the ZE belt work with the 20V cam gears.
being a quad throttle set up, will it handle boost?
i just want to know any of the problems that you can come accross when trying to use the 20V head on the older ZE engine, not worried about wiring as that wont be standard anyway.

thanks heaps guys, i hope you can help me out.

This is the original post Do we need to make another post regarding stuff thats over 99% of our heads?