I presume that upgrading to 12mm headbolts is done when you reach a certain power level,so that it gives extra clamping power and reduces the chance of the headgasket leaking?

What power level or state of tune do you upgrade to the 12mm bolts then,and where can they be got?

Thanks.

I've never seen any problems with headbolts on any twincam engine. Nor on our drag Delta with 800 hp on NOS and 2,2 bar of boost. Nor on my 2.4l engine with TD0620G runing 1,5 bar.

So I think the only one who needs these bolts is the company who makes them.

Thanks for the advice.

Are you using normal Fiat headbolts or aftermarket head bolts?

Stock )

Thats good to know so.

Thanks for saving me some money.


Any pics of vids of the 800bhp Intergrale?

Clamping power, great engineering term. Torque will be the same, fatigue resistance will be greater, but then you remove iron from the thread region of the block which may present it's own issues. Never heard of an issue with std bolts.

Here are some old pics, the car is destroyed after running at 13000 rpm. New owner didn't want to buy a better RPM meter )))

BTW the bolts are safe after all

WOW,loving the inlet manifold.

Any more infor on the car and the engine specs??

Thanks.

Now I am totally reassured.

Thanks for that.

It had many Gozzoli parts, like crank (2.2 litre), cams, valves, springs, rods etc.

Also ASSO pistons.

MSD ignition. Custom manifolds and fuel rails (injectors was 760cc + 1600cc).

GT42 turbo.

Dog tooth gearbox.
Dragtime was about 9+, but on bad road and some issues with mapping.

Smth like this ))) I was crying when it all was destroyed by a stupid mistake. Like always in Russia... We ruin our own achivements.