going to make a start on my engine next week, it run around 400bhp (cossie ybp with the squirters) got the pistons, bearings etc.... was going to use a cometic head gasket as i've used a couple in the past & good results with them, thing i keep pondering is what to bolt the head with???
i was going to use arp studs & nuts as i don't thing long studding is really needed at this level, but the only thing that bothers me is i've seen so many 200 blocks crack around head bolt holes (normally the 2nd one in) so my question is, is there a way to prevent this happening? is long studding the answer?

 

shouldnt u know working for PE? (not a dig btw, just in case it sounds like one)

 

the P.E. cossie engines were standard bolts & a group A headgasket, the guy who used to build the engines said he would build it for me if i wanted (but he said he would prefer a 2.4 crank & rods to use in it)
Times have moved on since P.E. stopped building engines so i thought i would get some other views.

 

 

standard bolts are cosmetic will be fine

 

cosmetic?, is that a head gasket with eye shadow spread on it?

 

 

not sure on that one mate, but i would go for the ong studs if you have the cash just for the safety sake, better and stronger as far as i know

 

Standard bolt will be fine Matt

Matt

 

either cometic or wire rung block with standard bolts.

imo of course.

 

The way I would look at it (DID look at it when my new blocked engine was built) ... Why not go belts n braces?? i.e long stud... If its apart anyway, whats a little more machining while you're at it??

At 400 brake I wouldnt want to cut corners ar worry about reliability...


(I also went for the gen WRC 4 layer gasket, though admitedly they're coin )

 

oh the cousin humor

 

I personally would not use the standard bolts UNLESS you don't mind changing the gasket every 8-12k miles (the bolts stretch under high boost application and the head starts to lift) depending on use (obviously if you poodled it around everywhere, then there wouldn't be an issue ). Obviously not an issue for someone as mechanically able as yourself, but those £200s for head-sets soon mount up if you intend on keeping the car. My Escort has done 30k with a WRC gasket / long studs and it has been a case of fit and forget, in view of this, you know what I will recommend.....

 

any proof of this mike???

standard head bolts (genuine only) have been recommended to me on lots of occasions,and i'm pretty sure i know of one car using them with nearly 700bhp

 

cheers Mike

 

Yep, my Sapphire. Before the WRC gasket was available, all I that you could use was the OE gaskets, standard head bolts or the ARP ones. ARP ones cause the cracking already mentioned, so my engine builder wouldn't touch them with a barge pole , so at the time I was stuck with standard bolts. I have done 60,000miles with this set set up, from mild to wild boost, and all I can say is that the standard bolts lift in ever decreasing mileage intervals, the higher the boost you run. Switching over to long studs completely eradicated me having to worry about head gasket issues...

 

must've been tightened wrong

 

Velcro it to the block Cousin Fucker

 

I agree 100% with Mike. I advise customers with standard bolts remove and refit new ones every 6000 miles if possible.

 

take it you replace one at a time
also do you torque it straight up

 

Personally i pull them out one at a time and then put the new one back in to 30ftlb.

Once all are in i tighten them as per the normal procedure. I have a couple of customers with Cometics on big miles (20K+) using this method, yet on my own car i never remember and have to change teh fooking gasket after 10 - 12K

Most people with blown gaskets will admit that when undoing the old bolts to do teh job, 1 or 5 were only finger tight. That is what we are fighting.

 

on the long studding

can you not use 6 long studs in middle and 4 ouetr ones arp?

this is what i was advised and ive onlg got 6 long studs is it worth getting all 10 done

 

i was told it breaks the block if all 10 are done

 

if your issues are with the std bolts stretching, then dont use stretch bolts

 

WHY not arp stud and nut kit?

Thats what i use on my saff only 300 bhp thou

If there bad why are they still sold?

 

if your going to build an engine do it properly its only a bit more machining.you dont need long studs but like mike and stu say if you want to keep your head tight then have them.the more boost the more the head will lift and move around but with proper long studs the head cant move around so no head gasket failure or cracked blocks

 

Long stud conversion is it only 6 studs that are drilled and tapped deeper into the block so that a greater torque can be used?

Sometimes i wish i was back in engineering so i can do this myself

 

yes thats right costina the reason the arp ones arent very good is because they still use the original bolt size holes and they still flex.ive got 10 long studs on my nikasil linered cgi block but iv had to use a wrc water pump for clearance hopefully block should be bullet proof

 

mine should be ok then only running 300 bhp got to be better than standard bolts anyway?

 

so will having long studs holding the head on so very tight,not cause further problems? i.e. they allow for no expansion at all

 

if you think back to the old f1 1.5 turbo engines they where monoblock so no head gasket or bolts so the better the head stays together with the block the better.they used to run upto 5 bar boost in qualifying

 

Stu, is this your recommendation for all states of tune, or, past a certain boost level ?

 

that's all well and good for an F1 monoblock,but with an Aluminium head and cast block,which both expand at different rates i presume? then these long studs don't allow for normal expansion rates,so what will give? head cracks,studs rip out??

just thinking aloud i'd like more discussion,although it's too late for me,my engine is in now

 

what about headgaskets, i know you hear loads of stories but a couple people have told me that the cometic gasket dosn't work aswell with long studs, how long should a group A gasket last with long studs?
are arp stud & nuts best avoided?

 

i wouldnt use a grp a for 400bhp i heard the limit is around 360

i was told to use a cometic which is the triple layer one and i was aiming for around 500-550

 

WRC gasket and long studding, if done properly with correct bolts and gasket really is FIT AND FORGET. I never worry about headgaskets any more and in 50,000 miles of running this kind of set up (20k on 515bhp engine and 30k on 477bhp engine), I have NEVER had a head-gasket failure (and on track I have seen water temps as high as 115°C ).

 

I have heard that long studding could make the block "bend" so that the crankshaft would not fit anymore properly. So that the only way to make sure it is ok, is to sacrifise one headgasket and build the engine up and measure that the crankshaft does line up correctly (if not then make it fit). But this is just what I have heard So I don't know how true this actually is.

 

all depends on the boost pressure really.