block and head bolts
 

hello i was wunderin if anyone could tell me if the block bolts are strech bolts?

ive just taken the engine out of me 96 wrx ej20,due to big ends!


any replies appreciated

thanks

No they're not..... they can be re-used....

Sorry to but in!! If there not stretch bolts then why the strange torque sequence?

Tim

Thats common with all engines, it's in order to add the stress to the heads in a regualted manner, otherwise the heads can warp as a result of being tightened up in the wrong order..!! especially if they're alloy, which they clearly are on a scoob!

This could end up sounding like a pantomime....I believe they are stretch bolts but can be used again.

stretch bolts are not designed to be used twise (not saying they cant be used twise) and just for the record i wouldnt regardless,the last thing i would want be doing is trying to sort out a head gasket after a rebuild for the sake of £100 odd

Torque and angle settings are not only for stretch bolts (ie bolts taken to yield in final tightening) it's just an alternative method to try and get a specific preload on the bolt without being subject to friction discrepancies.

I dare say a lot of research went into how to best tighten the bolts to get the right preload, and these sequences are refined with each revision of the car. Sometimes it's due to differences in parts (ie block casting) but some times it's down to improvements in the process.

The block bolts are fine to reuse.

I agree and I wouldn't but a lot of people have, without issue. They are better if "rested" before use, apparently.

There you go little bolts, you just and a lie down and a relax on the bench while I do all the hard work for a few hours lol.

I was advised to replace the stretch bolts when I had new heads (MY01), was told they could be reused but advise was while doing all that work best to replace with higher tensile non-stretch. Werent cheap mind !

Martin

Yes,got a set of arp studs on my 2.5,great quality,cost £160,but whats an extra £60 for peice of mind?!

Tim