im building a tuned 2litre silvertop zetec hoping for about 175bhp and reving to 7k, ive heard that the zetec botom end is quite strong, but are £60 of ARP big end bolts necessary or just a good preventative investement?

Whats everyone using??

I bought my zetec ones from http://www.northbridgemotorsport.com/

The caps didn't needs reaming (arp bolts would have required this)

I've done lots of track days and generally abused the engine and nothing has let go yet.

I guess while the engine was out it was a quick insurance measure to fit.

What about using 12.9 bolts?
I doubt you will see any increase in reliability than arp bolts.
Darren

f you are going to keep the revs to 7K then I would say no need, it is the revs that puts the stress on the bolts rather than power output. I have a soft rev limiter set to 7300 and hard cutoff at 7500. I use it quite hard on the road and 8k miles later still OK. Remember original are stretch bolts so no reusing.

I have a brand new set of ARP rod bolts still in their packaging (unopened) for sale. £55 inc postage.

My blacktop has been to 8k accidentally and 7800 regularly on standard bolts with no probs.

I am tempted to get some ARPs though to be safe.

Stu

Iv put arp bolts in mine to be safe. It does rev above 7k. Big end bolts are a weak point on a zetec engine.

My big end caps didnt need reaming either which they say they might.