12G202 head modding
Turbo Mini Forums

The 202 has a VERY good potential, but it needs work. The ports are very different from a standard 998 head, I don't agree with you there.

Oh, one more thing. I'd have the head bead blasted or soda blasted around the notch in the exhaust seat. They easily crack because of this and if it has, it's so futile spending hours and money on it.

Rusty by nature

For 424 euros you can drive yourself to me and back

Anyway, a gearbox from the UK to me is 30£ (40euros??). a cylinderhead takes up a litle less space, but i don´t think it is any heavier. Might try a different shipping company or plan your summer vacation in wonderfull Denmark :)

On 3rd Mar, 2011 Advantage said:
That's very kind of you but carrying an heavy item abroad can prove very expensive as I just checked.

It would be 424 euros to Danemark and back wich shall allow me to buy a neway set or have those done with proper tools ( )

If i have more toys than you when i die, I WIN

Sounds interesting but I have 3 heads to do anyway so I'll see if I can find a good and not too expensive machinist or buy a set of Neway (don't tell Vegard)

Rusty by nature

Sodablasting is a process where sodium bicarbonate is applied against a surface using compressed air. An early use was to restore the Statue of Liberty in the late 1980s.[1]

Sodablasting is a non-destructive method for many applications in cleaning, paint stripping, automotive restoration, industrial equipment maintenance, rust removal, graffiti removal, molecular steel passivation against rust, oil removal by saponification and translocation, masonry cleaning and restoration, soot remediation, boat hull cleaning and for food processing facilities and equipment.

Rusty by nature

usually I like spotting a big crack ...


On my way to search what has been said on how to treat one of those ...

Rusty by nature

If that is a crack, and not just a "cut" throw the head in the bin. Have it blasted to determine properly.

My english show its lacks here, what is the difference between a crack and a cut ?

The depth of the damage ?

Rusty by nature

Rusty by nature

three weeks and nothing going on, you're wasting your time with this head! it's scrap

Not posting does not mean nothing is going on.

I am working on the head and related stuff (such as relations to have the work done on a budget) as a draft for the 12G295 so I am not gonna bin it for a yes or a no.

But anyway, by my standart, 3 weeks is not too bad ;-D

Rusty by nature

I would put these effort into a 12g295..., Not my time though, your home your rules
cheers
fab

The 202 was for pepping up my 998 in N/A on the cheap.
Slightly bigger valves, flowed and polished chambers, high comp.
I was expecting 55 bananas or so (with an MD 256).

Now that it is officially out of business, the other option is my 295.
Quite bigger valves, flowed and polished chambers, lowish comp.
I don't know what to expect while it is still N/A (and it is likely it shall stay like that for a pair of years ...)

Don't know if it is better to keep the standart head ...

Rusty by nature

i use stones .

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

Thank you Robert.

Due to me not blasting the head as a starting point, I later found a crack.

Now I wonder if my 998 in N/A form is better with a high comp 202 (say 10,5) or a low comp 295 (say 9,4).

What is everybody's opinion ?

Rusty by nature

9.4 is right with a 256 cam, you'll not see any difference

That is good news.

It'll save head removal when I go turbo then (but will ask for the IC straight away)

Rusty by nature

ive just got one of these myself today. anyone got any tips of where to remove the material from in the chambers???

one day boost will be mine!

I did as per Vizard's recommendation.
I really recomend the purchase of the book : tuning the A-series engine (AKA the yellow bible)

The idea is to enlarge with a rad ius of 0,85 around the inlet valve within the gasket area.
Can't recall the radius around the exhaust thought ...

The cutting has to be at an angle from the roof of the chamber.

Vizard explains it much better than I do, really ...

Rusty by nature

And by the way, the 202 is off to my dad's place to try welding it.

I'll keep you posted of the progress

Rusty by nature

thanks for the advice and the added picture, speaks a thousand words !

so, about the welding, I have been told about arc and sticks of cast iron (we have an arc welder) but my dad is more keen on oxy acetylene to create a pool of metal in fusion (he knows his way with welding but has not done any heads so far)

To your knowledge, wich one has the most chances of succeeding ?

Rusty by nature

Edited by Advantage on 12th Apr, 2011.

Rusty by nature