Alternatives to hard-to-find cylinder head bolts

[rhymeface]

Hi all,

Following on from recent posts about my Nissan Sunny, I’m in the middle of a HG replacement and finding it hard to source new head bolts for the E16S engine in the Sunny - seems they’re non-existent.

Can someone tell me - can custom bolts be made according to spec? If so, anyone got a recommendation?

I’d re-use them but it seems the popular opinion is not to - do say if there’s reason to re-use them.

Cheers for reading.

[baracus]

Best bet would be to work out what threads/lengths/dimensions you need & then contact ARP. They have just about everything available.

[rhymeface]

Nice one. I did find them while researching the matter. Will look into it.

[vitesseefi]

Regarding re-use; rough and ready rule of thumb:

If head torque specs are given as torques only then re-use (assuming visually good) should be possible.

If head torque specs are given as torques followed a further tightening angle then there is an increased chance (though not certainty) that the bolts "stretch" ones that should not be re-used.

Sometimes proper factory manuals give length specs that determine whether ok to re-use or not.

ARP = good kit but $$$$$$$$$$$!

Nick

[rhymeface]

Haynes doesn't suggest either way whether to use new bolts.

Does give lengths and also 5th stage tightening angles.

[accord83]

Have you an engineering bolt supplier near you, preferably an old established business, take a bolt in and ask what they have like it. My local place is very helpful, I made some head studs for a pre-war Standard engine out of some long old stock Imperial cap head m/c screws they had. They had no idea what they were for originally, but they were ideal for me once I'd cut the heads off.

[Phil H]

Jul 17, 2018 9:24:52 GMT rhymeface said:

Haynes doesn't suggest either way whether to use new bolts.

Does give lengths and also 5th stage tightening angles.

Depends on what they give as the values - if it's something like 30lb/ft + 90 or 180 degrees, then they're highly likely to be stretch bolts. If 75-90lb/ft and 20 or 30 degrees, they may well be reusable bolts - subject to length.

Rough figures given for comparison..

Stretch bolts aren't, as the name may suggest, "elastic"; they use the deformation to effectively pre-set they clamping force they exert when stretched by a certain amount. This means that its sometimes tricky to "back engineer" a torque setting for a conventional bolt which also depends on the thread pitch used. Luckily, the likes of ARP do conventional versions for (orginally) stretch bolt applications, so it's not rocket science to take an educated guess from something similar.

[rhymeface]

Totally forgot that Americans call the Sunny a Sentra - eBay reveals a few options. Still a bit pricey but cheaper than standard ARP sets.

Thanks for all your help - educational in the least!

[stealthstylz]

There'll be something out of a different car that will fit. Get some measurements and I'll have a look at work.

[rhymeface]

Jul 17, 2018 19:18:51 GMT stealthstylz said:

There'll be something out of a different car that will fit. Get some measurements and I'll have a look at work.

Thanks a lot for the offer. I went with one of the sets from the US. Figured I'd just get on with it. Cheers though! Very kind to offer.

[skkylinedave]

I google the engine and got some results , there must be something avaliable in Australia or similar surely .

[rhymeface]

Yeah, I went with options in the US in the end. Ordered two sets but assuming they're both right, at least there's a spare set in the UK for anyone with a similar engine.

That said, if I'd known that something else would have done the job, I probably would have gone with that.

[cammy72]

If there is a market for them, why not order a length of suitable rod and have sets turned by a local specialist.

If you are stuck i can supply he appropriate rod length and have it laser cut to size and sub out the machine work.

You would need to specify the stud material though as there is such a variance in the strength of steel grades.

This way tou can have cap, hex or socket heads to suit and spread the load a bit better for higher performance applications.

[Deleted]

Jul 19, 2018 16:33:56 GMT cammy72 said:

If there is a market for them, why not order a length of suitable rod and have sets turned by a local specialist.

If you are stuck i can supply he appropriate rod length and have it laser cut to size and sub out the machine work.

You would need to specify the stud material though as there is such a variance in the strength of steel grades.

This way tou can have cap, hex or socket heads to suit and spread the load a bit better for higher performance applications.

Ever thought what lasercutting does to high tensile steel?
I take it you have very little engineering/ machining experience.....😊
Most bolts are hot headed and then have the threads rolled on to the blanks. Little to no turning involved and definitely go nowhere near a lasercutter...

[skkylinedave]

Laser cutting bar for bolts .......

[cammy72]

Jul 22, 2018 18:23:29 GMT @johnnybravo said:

Jul 19, 2018 16:33:56 GMT cammy72 said:

If there is a market for them, why not order a length of suitable rod and have sets turned by a local specialist.

If you are stuck i can supply he appropriate rod length and have it laser cut to size and sub out the machine work.

You would need to specify the stud material though as there is such a variance in the strength of steel grades.

This way tou can have cap, hex or socket heads to suit and spread the load a bit better for higher performance applications.

Ever thought what lasercutting does to high tensile steel?
I take it you have very little engineering/ machining experience.....😊
Most bolts are hot headed and then have the threads rolled on to the blanks. Little to no turning involved and definitely go nowhere near a lasercutter...

The idea was to laser cut the blocks then have them machined,  you order block from the metal supplier and ..... guess what .... the scissor fairys cut it     Also the CR sheet will 110% be laser cut before you get it.     You would be surprised how little heat there is in the new Trumpf fibre laser cutters, no water cooling just liquid nitrogen.         A bolt without a head is a stud not a bolt       

[Deleted]

Jul 23, 2018 17:55:12 GMT cammy72 said:

Jul 22, 2018 18:23:29 GMT @johnnybravo said:

Ever thought what lasercutting does to high tensile steel?
I take it you have very little engineering/ machining experience.....😊
Most bolts are hot headed and then have the threads rolled on to the blanks. Little to no turning involved and definitely go nowhere near a lasercutter...

The idea was to laser cut the blocks then have them machined,  you order block from the metal supplier and ..... guess what .... the scissor fairys cut it     Also the CR sheet will 110% be laser cut before you get it.     You would be surprised how little heat there is in the new Trumpf fibre laser cutters, no water cooling just liquid nitrogen.         A bolt without a head is a stud not a bolt       

Like I thought,you obviously don't have a clue as to how bolts are made....😊
Good to see that you know the difference between a bolt and a stud.😊

I doubt I would be surprised at how little heat a Trumph laser cutter generates,as a lasercutter cuts steel by melting it.😂
Due to the nature of the process you will always get a HAZ area adjacent to the cut that is harder than the rest of the plate. 
Sorry to burst your bubble,but bolts are made from roundbar, not lasercut from a block of steel. Never have,never will be ..
One method of making hitensile bolts is to take roundbar with the diameter of the bolt you want to manufacture ,crop the bar to length and heat up the blank with an induction heater before Hot heading in a hot forging die to form whatever head form is required. The blanks are then normalised before having the threads rolled on. Then final heat treatment and surface finishing,i.e. Plating. 

[colnerov]

Hi, For the uninitiated. -

[Deleted]

Hot heading process