[Mk2] [NA] Forged internals... (WARNING huge post!!)

[KarlBristol]

I like to have something to keep me busy and aim for with the car. Once the 1MZ-FE VVTI engine is finished by Peter I am looking at future long term possibilities, and one of the options Im looking at is possibly forging the internals.

Correct me if Im wrong, but as far as I can see the advantages are increased reliability, endurance and it future proofs it if I look at adding a supercharger or turbo in the future. The only negative that I can see will be the cost

What are other people's views on forged engines?

For me I'm thinking that I have got the main purchase out if the way with (the engine itself and its refurb) so the parts for forging I can buy gradually over time... Obviously the 1MZ is an Ali engine and as such all of the forged parts will also have to be Ali as well which will push the costs up even more...

Any ideas as to exactly what parts I would need to be looking for (I've put my ough idea below..)

A rough (and I do mean very rough) price bracket?


I was thinking I would need the following for a half decent engine upgrade...
- Forged pistons
- Forged rods
- Forged crank
- Possibly a forged head?
- May as well upgrade the injectors whilst I'm there...

Can any of these parts be bought aftermarket or utilised from other car engines or do I have to get them all custom made for me?


Sorry for the mammoth post I just wanted to see exactly what the future options and their associated costs were
Thanks

[badgerbob]

in regards to the ali block, could you possibly sleeve it? like these for example http://xxxx/catalog/p ... cts_id=197

In the long run i can see these being as good if not better but my only query would be the expansion rates of the two dissimilar metals

[gavinda]

it has iron sleeves from factory.

karl there is a bit of nonsense in your post. no offence
you dont need 'ali' parts as you put it.

decide if you want to turbo as you will want lower compression pistons to
run more boost.

forged parts are stronger if you want to simplify it.

also the stock crank is forged steel as toyota have done in their vehicles for a long time.

[gavinda]

i would look into the crankcase ventilation/ breather system on the engine if i was going to be turbocharging it as i suspect you may have problems with blowby bullding up in the crankcase.

[ashley]

As Gav says- if you plan to go forced induction then you'll probably want lower compression pistons. But it makes no sense to use these until you go turbo/super charged as it will lower torque/ power.

For a forged build you would consider:
- Pistons
- Con rods

You do not need a new crank, and you don't "forge" the head, although you may look to instal larger valves, and different camshafts.

Sounds like you need to do some research, get yourself a couple books to read while you're off work:

http://www.amazon.co.uk/Four-stroke-Per ... 913&sr=8-1

http://www.amazon.co.uk/FORCED-INDUCTIO ... 947&sr=8-2

[synXero]

If you're going to charge it either way you will need to think about the stock compression ratio, and what sort of compression you'd want under a boosted application. Lots to think about there.

I'd suggest that you maybe factor these considerations in earlier, and discuss with whoever is building your engine...?

[KarlBristol]

No offence taken at all - I've got very limited knowledge in this area which is why I asked. Any help, pointers, or reading material is very appreciated although you may have to dumb things down for me sometimes

It would probably help to know exactly what I'm striving for with the engine....
My goals for my engine in the first instance are to have it strong, reliable and usable. I want a bullet proof engine, and to open it up to future modification possibilities. If I was going to upgrade it even further I would probably add a supercharger rather than a turbo (especially as TRD make a supercharger that fits with minimal fiddling). I'm preetty set that I don't want to go down the turbo route, I want something different to the norm where engines are concerned.

So I can scrap having to replace the crank then, that's good news

My ignorance made me believe that the engine was for the most part Ali, and as such I thought that I would have to have Ali forged parts due to expansion rates, strength differences etc... I had horrible views of pistons going through the top of the engine! Lol.

Another epically long post from me lol
Any further help or a point in the direction as to what I could add onto the shopping list would be perfect

It would be nice to price it all up so I know roughly what I need to save...

[KarlBristol]

Thanks for the links - I will order those now and start reading
It will help to fill in some of the gaps of my knowledge (of which I'm ashamed to say there are quite a few - but we all start somewhere ). I can do basic spannering and have a half decent knowledge of how an engine works/is put together but the world of engine modifications is alien to me.

Revised idea then...
So the plan is to write a comprehensive list of parts needed and build them up over time so that the finances don't suffer too much at once I will stick everything to one side until I have a TRD supercharger as well (there is a cheap'ish one on twobrutal atm but with the engine swap I just can't afford it right now). Eventually install everything at once.

This is a real noob question so apologises - why do forged internals give lower torque/power? Is it as there is more density/weight there to shift around due to the forged pistons etc?

Last one... You say you don't forge a head - why not? Surely a custom forged head (pricey though it would be) would prevent the head cracking at all. You would also be able to incorporate exactly what valves and camshafts you want. That may be an idiotic question, I'm just trying to wrap my head around things (no pun intended! Lol)

As Gav says- if you plan to go forced induction then you'll probably want lower compression pistons. But it makes no sense to use these until you go turbo/super charged as it will lower torque/ power.

For a forged build you would consider:
- Pistons
- Con rods

You do not need a new crank, and you don't "forge" the head, although you may look to instal larger valves, and different camshafts.

Sounds like you need to do some research, get yourself a couple books to read while you're off work:

http://www.amazon.co.uk/Four-stroke-Per ... 913&sr=8-1

http://www.amazon.co.uk/FORCED-INDUCTIO ... 947&sr=8-2

[gavinda]

certainly easier with a supercharger as trd and others have done it with the 3MZ so no unexpected problems to overcome (i.e. the breather system with turbo+high boost)

shopping list would include:

forged pistons and rods
arp head bolts, mls headgasket
supercharger kit
engine management+wiring including new sensors

headwork/cams- probably not necessary dependent on goals as N/A cams are more aggressive. but will need to address overlap(ie increase LSA)

[gavinda]

nothing to do with the forging karl its because lowering compression ratio lowers power/torque.

[KarlBristol]

Absolute star thank you
I look forward to the new reading material being delivered

I can feel the money leaving my bank account as we speak!

What websites do you mainly use to get these sorts of parts from?

[gavinda]

What you are intending on doing is not the norm and i like/respect that.

however this means it is not as easy to get hold of performance parts-forged pistons, rods etc
as they are not likely to be off the shelf items.
(this means custom items with high prices)

[synXero]

Have you considered a 2gr might be a more economic and generally more sensible option?

If sensible isn't the call of the day batter on but gear up for the costs involved. You'll have heard names like Cometic for headgaskets, ARP for studs, Eagle for con rods, Wiseco for pistons. These sorts of guys might be able to help you in some way.

[KarlBristol]

Pretty much as I though. Oh well - if I was that concerned about money I wouldn't own 3 cars in the first place!

I've been scrolling through various websites that build parts of these engines but its hard to know who a reputable and who aren't. Once I've done some more research I will post up my proposals of exact parts (specifications, companies, links, etc..) and probably ask for advice on them so I know exactly what I'm getting.

I like my car being different. I've got the cosmetics, suspension and braking aspects of the car pretty much exactly as I want them (all new and a bit different) so the next logical step was the engine.

I wanted a V6 and something completely different from the normal V6 swap (3VZ). Hence I went for the aluminium 1MZ VVTI. However I now know of x2 others being built which is why I a increasingly thinking of my future engine plans. Plus i cant deny that I like tinkering on the car! hence the plans to forge and TRD supercharge.

I'm always open to suggestions though and any other or unique ideas are always greatly appreciated

[KarlBristol]

Have you considered a 2gr might be a more economic and generally more sensible option?

If sensible isn't the call of the day batter on but gear up for the costs involved. You'll have heard names like Cometic for headgaskets, ARP for studs, Eagle for con rods, Wiseco for pistons. These sorts of guys might be able to help you in some way.

2gr is an awful lot of money up front all at once that I just couldn't justify to the girlfriend the route I've taken is a big chunk of money for the engine swap and then I can play with parts/upgrades slowly within a monthly budget so it suits me a lot better.

I probably couldn't have stretched to a 2gr in the first place if I'm being completely honest.

On a side note there are quite a few 2grs in MR2s now... My car wouldn't have a unique engine if I just dropped a 2gr in it. I like pushing it to be unique...

When the time comes I will have to sit down with Peter and have a serious talk about how to reach my goals with it and what exactly we can do to give it that "je ne sais quois"....

[synXero]

2gr is an awful lot of money up front all at once that I just couldn't justify to the girlfriend the route I've taken is a big chunk of money for the engine swap and then I can play with parts/upgrades slowly within a monthly budget so it suits me a lot better.

I probably couldn't have stretched to a 2gr in the first place if I'm being completely honest.

Remember that the process of fitting all these parts is going to be extremely labour intensive, experimental to some degree, and colossally expensive! You are right you can collected the forged components and box them up one by one, but when it comes to it and you've assembled the full fueling system, the forged internals, the supercharger itself, the bracket to fit it (do not underestimate the cost of these!) and the modifications to the intake system to support it, etc. etc. etc.... You have to pay someone to fit it, ideally all at once or you will be spending even more excrutiating amounts on repeat engine disassembly, reassembly, and then remapping sessions.

Now I don't like to portray the negative side of it because it's unusual or whatever. Just be wary and remember the cheapest way is probably to do it right (read: the way you want it to be) the first time round, even if it means not doing it for some time

Protok would testify that the cost involved with his turbocharged ITB Beams engine vastly exceeds the cost of getting a 2GR conversion. I am sure he loves the car unequivocally, but I bet he wishes he'd 2GR'd it

[bobhatton]

nothing to do with the forging karl its because lowering compression ratio lowers power/torque.

It does but going from 9.0:1 to say 8.0:1 you will lose only3%

[uglee]

Have you considered a 2gr might be a more economic and generally more sensible option?

If sensible isn't the call of the day batter on but gear up for the costs involved. You'll have heard names like Cometic for headgaskets, ARP for studs, Eagle for con rods, Wiseco for pistons. These sorts of guys might be able to help you in some way.

2gr is an awful lot of money up front all at once that I just couldn't justify to the girlfriend the route I've taken is a big chunk of money for the engine swap and then I can play with parts/upgrades slowly within a monthly budget so it suits me a lot better.

I probably couldn't have stretched to a 2gr in the first place if I'm being completely honest.

On a side note there are quite a few 2grs in MR2s now... My car wouldn't have a unique engine if I just dropped a 2gr in it. I like pushing it to be unique...

When the time comes I will have to sit down with Peter and have a serious talk about how to reach my goals with it and what exactly we can do to give it that "je ne sais quois"....

From experience I collected most the parts to supercharge my 3VZ. Had forged pistons, Supercharger off an early XJR, Link G4 management etc etc.

By the time I worked out how much I'd have to pay for further stuff like headgaskets, custom ally work, mapping etc I was firmly in 2GR purchase and install territory.

Couple that to an engine never really designed for forced induction and the no doubt much reduced reliability that comes with it, you'll probably be constantly fettling it to keep it running right. All for not a great return on power per £ spent. I therefore decided to shelve my supercharging plans and go 2GR.

If you know of anyone nearby who has one (there are only 4ish roadworthy 2GR Mk2's in the UK at the moment) Go see if you can be taken out for a run. You'll honestly be shocked at the way it goes and will see no need to go any further as far as a fast road setup is concerned.

Upto 100mph it will hang with my RS6 in acceleration terms, obviously after that pure HP dictates what will happen, but it doesn't take away the fact that these are seriously rapid cars for the road.

You might want to be different, but when the costs start getting into the 10's of 1000's of pounds you might start to question your sanity.

Again, been there done that