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Steve Webb
30-08-11, 08:27
Back when I used to frequent Integrale forums, upgrading to 12mm head studs and bolts was discussed quite often. Doesn't seem to get brought up on here all that often, so has anyone done it or plan to do it?
It might be down to the fact that they were all into running large amounts of boost, 1.7bar or so, whilst we all seem more occupied with sorting out the breathing of the engine first.
Brul(tm)
30-08-11, 08:29
so has anyone done it or plan to do it?

Planning to use them when the building starts.

Regards,
Marc
Steve Webb
30-08-11, 08:35
Planning to use them when the building starts.

Regards,
Marc

What boost are you planning for eventually? 1.35bar + or is it just for reliability\flexibility?
Brul(tm)
30-08-11, 09:22
What boost are you planning for eventually? 1.35bar + or is it just for reliabilityflexibility?

It's a fun car, so I have to wait and see what's going to happen ;)
I am after 400BHP, so I think I'll have to see and wait what adjustments (besides the forged bottom, worked cylinder head and different turbo) are necessary. I guess it wil probably be around 1.5 bar, but again I have to wait and see how everything works out.

Regards,
Marc
colibry
03-09-11, 21:22
above 350hp 12mm bolts are musthave... if u dont wanna have trouble.

regards coly
jimnielsen
03-09-11, 22:48
In my opinion 12 mm head bolts would be nice - but I am not using them...From my own personal experience I would recommend using the simple sub $100.00 Cometic head gasket. I have reused mine 4 times so far and it seals perfectly. I am running between 1.35 and 1.55 bar. I am using ARP head bolts - but just the normal diameter.

There are so many thing to spend money on with these cars, but for me the stronger head bolts would not be on my list.

Also I have found that with the right cams you cam make a lot of power without needing more than 1.4 bar boost - And that is on a car with no inlet manifold porting at all..

cheers, jim.
mpampis_
04-09-11, 07:34
i think, if you porting nicely the head, manifold and more aggressive cams you can have 400 hp at 1,5 - 1,6 bar boost (it depend on the tubro you have). i have to ask something else. what about the head gasket? actually about the compression ratio. the stock cr is 8.00:1, what is the max boost with this cr for not having problems?