Help with a bolt. Please

Dave · June 21, 2009, 00:54:39

O.K I have another little project on the go but I am stuck.

I want to use these fancy bolts below.

But I need to source a 12.9 strength version as these are only 10.9.

& what the hell would you call these type of bolts??????

Anyone got any ideas.

Cheers
Dave

cossiemk2 · June 21, 2009, 01:01:08

What are they for Dave?

Main cap bolts?

Dave · June 21, 2009, 01:02:31

No head bolts hence why 12.9.

cossiemk2 · June 21, 2009, 01:14:43

Are they M12?

Got some longer bolts for my main caps with the girdle in between.

They are 12.9 120 mm long.

They have an Allen head tho, never seen that type of bolt before.....

Dave · June 21, 2009, 01:19:30

I think you mis the point mate.

See the head of the bolt it is threaded so you can screw another bolt into it.

They are M12 x 1.75 x 95mm.

I am actually using them to brace the head & it's not a 24V either

cossiemk2 · June 21, 2009, 01:32:10

OK i might be missing the point here.

But it's a head bolt. What's bolted on top of it then?

Dave · June 21, 2009, 01:35:58

O.K they are not STD but something I have got hold of thinking they was 12.9.

They are not & I can not find a 12.9 version hence why I need help!

A metal brace I have made bolts onto the top of them.

TwinTurbo · June 21, 2009, 08:44:13

Err.... Why not welld on a m12 nut or something on top of a standard head bolt?

TT

scud · June 21, 2009, 14:31:01

that will most likley weaken them

Cortiworth IV · June 21, 2009, 15:06:50

Quote from: scudthat will most likley weaken them

Jupp. Welding a bolt effectivly makes it a piece of string.

Leebay · June 21, 2009, 15:48:10

Dave drop AHC a email with that picture and the spec you require they might be able to source some for you.

Site - www.ahc-camberley.co.uk

Email - sales@ahc-camberley.co.uk

Dont have much of a selection on the website but the back of their shop is full of obscure types of bolts/fixings.

Dave · June 21, 2009, 23:23:18

Cheers I will try them.

I once had to weld a nut onto a stripped torx head stud to remove it.

The complete head of the bolt snapped off

So welding is not a option.

To much work & money involved to bodge it

Thanks for the idea thou TT.

Dave · June 22, 2009, 10:57:58

I spoke to that company & they have never seen a bolt like it.

It looks like I am going to have to get them made

Leebay · June 22, 2009, 18:10:11

Bugger

turboshed · June 22, 2009, 19:27:57

Dave I can get them made,you might be able to get the opposite type bolts(male thread on top off the bolt head won't be cheap but will be cheaper than most pay,not sure if i need these bolts as my deck height of the heads is over twice as thick as ford heads and should'nt flex as much.I will ask squeak to see where his heads cracked when he was pushing it on the dyno.think it was straight thru the spark plug.
I can understand the end of each head can flex even with ht bolts it would make either no.1 3 4 and 6 split the heads thru the spark plug as this is the weakest point.I was thinking end bracing on the heads which drop down to the block.
I'm away for a wweek in cornwall so cant do anything untill i get back

Dave · June 23, 2009, 02:53:05

O.K the cats out the bag now

I need them bolts for a brace to stop 12V heads cracking when running high boost.

After talking to a number of old timers who raced the engines we now know the soluction.

It's tried, tested & works but now just needs the finishing touch.

Dam them bolts!

sierra3dr · June 23, 2009, 06:37:32

They would be known as a threaded adapter with a female insert. Here's a start http://www.flexishaft.com/AdapterCustom.htm]http://www.flexishaft.com/AdapterCustom.htm
http://www.midwestcontrol.com/catdisplay_short.php?pg=176]http://www.midwestcontrol.com/catdisplay_short.php?pg=176
Have a word with your local engineering supplies.

Dave · June 24, 2009, 01:38:30

Now that's more like it. Cheers.

I have asked all the engineering firms I use & looked on the net.

None of them had a clue, most saying "that's a custom part that is"

Dave · July 21, 2009, 00:59:04

Well now the holiday is out of the way I am back on the case.

Every bolt maker I have mailed have said the only bolts they have ever seen like it are one offs except for a small range that looks similiar but is only 8.8 grade.
Even the firm who made that bolt says it is only made for 1 customer to their spec.

Found a few firms willing to make them for me, two in particular.

Even ARP is interested in adding them to their catologue if I get them to make them & give them all the specs.
But no gonna keep it British

I have uped the spec now to 14.9 which is the same as ARP anyway.

It will be a set of 16 x 2.9 12V head bolts for extreme boost.

The 8 outer 12V ones are special as a surport bar bolts to them to stop the head cracking problem that boosted 12V's surfer from.
As designed & proven by TT.

Firstly is anyone interested if say it costs 150 pounds for 16 bolts.

You will never buy head bolts again as these can be used again & again etc etc.......

Mikey J · July 21, 2009, 10:30:51

What's the lead time Dave and is it possible to order just the 8 outer bolts for a blown 12v?

Cortiworth IV · July 21, 2009, 10:41:30

Quote....
Firstly is anyone interested if say it costs 150 pounds for 16 bolts.

You will never buy head bolts again as these can be used again & again etc etc.......

150 pounds for 16 14.9 bolts? Sounds like a bargain to me! I don't need any of those, tho.

I recently enquired some simple M12 14.9 main cap studs from a local retailer and they were about 50 pounds...each!

BTW; are you sure the threads in the block are strong enough to tighten the 14.9 bolts properly?
ARP recommend 160-165Nm, when using 30 wt oil as a lubricant, to preload their 220 000 psi bolts.

Dave · July 21, 2009, 14:11:54

Mike they say it will take 4 weeks.

I may go back to 12.9 as it will make it far cheaper as then you only need the 8 outer special ones.

It's just they are willing to make 14.9 for the same price.

14.9 is 200,000 - 230,000psi which is about the same as ARP spec studs or bolts.

ARP spec them for the block so I guess they must be O.K as indeed they are used on loads of similiar spec blocks.

Also Sparkplug off here has ARP studs & has had no problems.

For 16 ARP studs they want 150 pounds so my custom made ones are cheap.
God I hope they have got the quote right

Dave.

Mikey J · July 21, 2009, 15:30:44

Thanks Dave.

Also, I've been using arp's on the heads as well for 12v and 24v. They clamp down nicely.

littlegems4x4 · July 21, 2009, 20:10:38

Ah ha, this is what we've been talking about, may well need a few sets of these myself. Just paid my tax bill though so could do with building up some cash again first

sierra3dr · July 21, 2009, 22:42:02

Quote from: DaveThe 8 outer 12V ones are special as a surport bar bolts to them to stop the head cracking problem that boosted 12V's surfer from.
As designed & proven by TT.

ooow...I don't like the sound of that...head cracking problem? Does that apply to the 2.8er aswell as the 2.9er?

Quote from: DaveFirstly is anyone interested if say it costs 150 pounds for 16 bolts

I assume,the more orders are received,the cheaper they'll be?

Quote from: DaveYou will never buy head bolts again as these can be used again & again etc etc.......

I bloody hope I don't have to take the heads off again,with or without these superficial bolts

Dave · July 23, 2009, 01:48:12

The 2.8 heads need mods to stop excess heat problems first then this mod.
But saying that never known a 2.8 running more than 18psi so can't confirm if cracking is a problem or not.

Yeah of course more made & the price drops.

Superficial bolts!
Well the fact they crack is a known, so many cases it's actually common on anything much over a bar.
In the states it is common on N/A engines to & you can buy heads that have been cast far stronger than Ford did them.

That's one cure for it.

But if you already have worked heads maybe costing 600 or more to copy then the brace is the answer.

Tested & used on race engines upto 25psi from 1988 to today.

They are rebuilt every few meets & the brace is clamped with longer head bolts.

But this makes removing the rocker covers & even the sparkplugs hard work.

Hence my re-design with a easily removable bar & improved stronger materials.

Quote is confirmed & I am going for 14.9 strength bolts as it's the same cost as 12.9 so why fit weaker bolts

8 special bolts is £80 + postage.

Still waiting for quotes on the normal other 8 bolts but in 14.9.

Super 12v · July 23, 2009, 09:55:05

How does the brace help over using normal 12.9's? As the failures of cracking I've seen are from flexing the head when lifted at peak cylinder pressure normally associated exceeding 1bar boost, which is remedied just from using 12.9's bolts. Is this going into a realm's that far exceeds this as even 1.3 bar would be fine on 12.9 bolts.

I know Squeak has run up to 27 psi on 12.9's but I suspect not for sustained periods, (purely because gearboxes have been a limiting factor )

Cheap mod though in the grand scheme of things though.

Dave · July 23, 2009, 11:09:54

It may be that ARP studs or the 14.9 bolts would be O.K upto 25psi.

All that I know is with 12.9 bolts the head will still crack across the spark plug hole.

My car has used the 12.9 bolts since 1992 & it cracked a head a few years later, other Minker owners have also had cracked heads.
12.9 bolts & 12.9 spacers are STD on Minkers.

The engines TT built for racing used to use the same as the Minker's & would crack a head once or twice a year at 25psi.

A few things where tryed but the only thing that worked was bracing them outer bolts/head.

They never had another problem with it after that.

It just gives the head more surport where it is weak & reduces any flex of the head under high boost but to be honest who knows just that it worked.

I am not trying to sell it, I am just giving people the chance to get something that normally would be mega bucks at sensable prices.

I plan to order Monday so be quick.

Super 12v · July 23, 2009, 11:40:27

Cheers it's ok, I won't be ordering. Not because I don't agree with what you say as it's obviously tried and tested, purely because I won't be at those level's.

Out of interest the Minker heads were just porting, flow work and sodium filled valves? I take it they didn't have the machined chambers as they had the AE pistons?

Dave · July 26, 2009, 00:44:26

No they had far more work than any of the others.

TT280's where same as TT225 except had bigger sodium filled exhaust valves & ported.

The Minker had all above + it's exhaust ports where enlarged further & polished.

The combustion chamber's where smoothed to remove potential hot spots & also polished.

Also they where fitted with 12.9 bolts & 15mm hardend spacers.

This changes the cast metal structure, makes it stronger & removes stress from the casting so heat don't effect them so much.

Help with a bolt. Please

Super 12v

Super 12v