pinto piston problem

[stevio 0]

hi guys, new to this so bear with me, bought a s7 running 2lt pinto with modified cosworth rod and pistons. problem is a piston as blown and i cant get a replacement

i need a 90.8 +1.55mm with a circlip gudgeon pin, tried burton power ect and i am having no luck. any ideas would help please

[blue 50]

Try brands hatch performance 

01474 850666

[theduck 866]

Another recommendation for Brands Hatch Performance.  Get most of my pinto bits from them

[apgodden 15]

I have bought engine bits from Brands Hatch Performance very helpful people.

[stevio 0]

cheers guys will give them a go 

[richyb66 1,212]

You probably just have  + .060" pistons. The circlip groove is neither here nor there because they can be added easily. If you still struggle, let me know and I can put you in touch with someone but the would probably need to have the piston and rod to measure to ensure the piston size is correct and then machine the required grooves.

[stevio 0]

hi richy, problem i have is the engine builder, is telling me the gudgeon pins are different sizes on the pressed pins and the circlip pins, i already have purchased correct size piston but it cannot be fitted to exsisting con rod ( means i may have to buy a complete set to which i am trying to avoid) current engine only done 1000 miles, been stood 5 years in garage.

[richyb66 1,212]

I think I'm missing something here. If you have new and old pistons, old pin and old rod then they should have everything there to measure. Also presumably the new piston came with a pin? All the pins rotate in the piston ,Pinto pins are a press fit into the rod whereas the Cosworth rod would have a rotating  (floating ) pin and hence needs retaining with circlips to stop it moving sidewards and touching the bore.

Assuming the current pistons are 2.8 V6 and you're using Cosworth rods they what is the issue with fitment? The Cosworth rod is wider at the small end that the 2.8 rod so it needs to be narrowed to prevent the side of the rod potentially contacting the piston. However if the rod already had a 2.8 piston on it, it should have already been done.

[stevio 0]

hi richy, i see what you are saying. new piston have come with pins, it is the engine builder that has told me it cant be done, i am going over to see them in the morning (with measuring calliper's in hand) i will let you know the out come. in my mind i agree there shouldn't be a problem. fingers crossed

[stevio 0]

hi richy, everything as measured the same and the rod already modified, i just need to get the circlip grooves cut into the piston. dont know what he was flapping about.