slowpoke

what is the yb number again and does anyone have a price from fords ??

is it true the late esc cos gasket was the same as a grp a one ?

matt

slowpoke

anyone please ?

matt

Andreas

yb1261, doubt its exactly the same as the group a.

slowpoke

does anyone know how much one of these are from ford ??? doo ??

and how good are they ?

thanks andreas...............matt

Anonymous

According to what ive read on here, you need to wire ring the block to get the most out of these gaskets.

Karl

The std escos head gasket is YB1261 the GpA YB0611.

The gaskets are identical in construction with the exception that the the YB1261 has two crimp rings around the oil drains, which helps prevent oil seeping into the gasket around these oil ways.

Power wise both gaskets are suitable for up to 300bhp in std form and 500+ with wire ringing.

The use of either of these gaskets over around 300bhp without wire ringing will result in premature failure as the gasket fire rings gradually get "blown" out making the fire ring oval shaped with eventual failure. Exactly how long it will last is debatable as its dependant on how much on boost driving the engine sees, but expect either of these gaskets at over 350bhp to last less than 10,000miles.

slowpoke

karl would a grp a one last longer on a 340 hp car do you reckon ?

thanks guys............matt

Karl

No

Disabled Account

Karl...........BTW with either 1261 or 0611 gaskets and wire rings on an engine with 450 - 480 BHP would you use the standard head bolts or "special" ones...i.e. ARP ???????

============================================

slowpoke

hhhmmm back to the drawing board again lol

still looks like im gonna be trying one of those ferriday engineering copper gaskets

thats when this one does go on my car lol

thanks guys.................matt

Karl

Doug,

The only method to correctly hold a head down on a YB is Genuine Cosworth std head bolts. I have tested every method extensively (i.e. 6 long studs, 10 long studs, ARP, std) and done a detailed survey of block distortion, residual clamping force remaining, block cracking and effect on head flatness and distortion.

The results are STAGGERING and not what everyone would expect!!

Disabled Account

Thanks Karl!

Dave Henshall

if its not been wire ringed - fit a cometic 3 layer one, no need for wire ringing and the gasket is about 130 quid - which will be cheaper than getting it wire ringed anyway .

Mike Rainbird

iTrader: (3)

Karl,
I found that in my experience that the standard gaskets still failed even with wire ringing at the same mileage sort of mileage you quote without - 8-12,000 miles. I attributed this to the fact that the standard bolt is a stretch type and that the high boost levels lift the head, which causes the failure. Is this something you yourself have found?

Karl

Hi Mike,

No it's not an issue I find. What I would say to you is a lot of people wrongly diagnose head gasket failure. For example you are saying the head bolts stretched and lost clamping force? How did you ascertain this?

As standard the finish on the block face from the factory is a mix of between acceptable to poor. The reliability of any head gasket is a function of many factors but the two most important factors are correct flatness and surface finish and uniform clamping. This can only be achieved correctly if you have the correct equipment and knowledge to machine the engine componets correctly. Even then you must prep and assemble the engine correctly!

If you like I'm happy to discuss my findings with you on this, off this site, as its something I've been gathering info on for over 5 years now and now have enough surrogate data to draw a conclusive answer!!

You will be shocked Mike!!

Mike Rainbird

iTrader: (3)

Hi Karl,
Feel free to mail me . Regarding the failures I "used" to experience, the head was always prepped correctly (something Harvey is meticulous over, as he knows that most repairs fail almost instantly if this isn't done correctly).

However, in my favour I did always catch the failures before they became severe, as I know what to look out for on the Cossies, so I would be able to spot the failure when the hydrocarbons were only just becoming detectable in the coolant. This also had the benefit of meaning that the head required very little machining to get it perfectly flat.

I always just assumed that it was caused by the head lifting from the 34psi peak / 26psi that I was running at the time. However, after having four head gasket repairs (at £250 a time) over a number of years, I finally bit the bullet and on the fifth time had the engine long-studded (which coincided with a rebuild / upgrade). Since having the WRC gasket and this method of clamping fitted, I have NEVER had a gasket failure in over 45k of driving . Whereas before I was getting them at least every 8-12k.

Given that the last cars have been abused even more than the 385bhp engine, I am pleased with my experiences of long-studding. However, that doesn't mean I am not open minded, and I agree that ARP studs in a Cossie block are the worst mod EVER .

wimwerf

but im driving almost 2.5 years with ARP's.....with stage 2 and later 3....no prob. and thats with 40000miles with a 1261 headgasket.

markk

iTrader: (2)

this could well be another interesting head gasket/bolts discussion !!

Anonymous

Im very keen to find out what the problem is with ARP bolts, ive used them in almost every engine ive ever built for mains, head, and big ends, and ive NEVER had one let me down.

Why is the cossie motor any different to other engines in terms of what studs to use?

Any info greatly appreciated BEFORE i fit them!
(have already bought a set but i wont use them if there is a better alternative)

ImaRacing 700

I have also tested head gaskets and bolts...my experience as follows:-

Std head bolts on a multi layer or Coopers rung block do not have the required clamping to stop the gasket blowing under high boost pressures....Std head bolts are good upto t34.63 conversions on grp a gaskets.My T4 @ 34 psi lifted the head and cracked the block around the middle 6 bolt holes,if i'd been using ARP's this would NOT have happened.

ARP's i have used and never had any problems..BUT beware they have to be installed CORRECTLY like COMETIC head gaskets have to be!!!!!!!

Now on WRC middle 6 long stud std out 4..as my block came with this...have full confidence on this as the middle 6 is where the most force is and my head wont lift like it would on std head bolts and crack around bolt holes!IMO its all thats needed as the outer 4 do not want to be as tensioned as the middle 6 (std are stretch,WRC are semi stretch) or block cracking can occur again culminating in premature gasket failure

markk

iTrader: (2)

wavy plate anyone ???

PAUL V

1st can we keep this topic interesting as i don't think we have had a full on debate on his subject

Ok karl as i work on Motrocycle Engines and have vast experance with head gaskets and surface finish can you please advise on type of finish req for the Head being Aloy and the Block being Cast iron ?

Why i ask is i have a Small turbo Escos that i will be doin the Head gasket on soon and sometime plan to change the turbo to gain 350-370 BHP

Also can the wire ring be installed with the Engine in still in the car assuming the surface finish if ok.

Thanks in advace for your input

PAUL V

back up

Billabong

https://passionford.com/forum/viewto...ight=wire+ring may be of interest Prox...??

AFAIK, wire ringing the block can possibly be done in situ with a special tool.

PAUL V

Thanks for that I woner where i can buy the tool to do it ?
I would like karl to explane the finish that should be on the head / block ?

Ian M

after replacing more than my fair share of head gaskets over the last 10yrs and cracking a 200 block i am now convinced the best method is as follows.
1 deck the block so it is perfectly flat with a good surface finish.
2 lightly skim the head again perfectly flat with a good surface finish.
3 counterbore the 10 bolt holes in the block to a depth of around 10mm.
4 cut a radius on the edge of the bolt holes do not leave sharp edges.
5 use a multi layer steel gasket.
6 standard head bolts correctly torqued ensuring the bolt holes are spotlessly clean before fitting.
i dont believe the 6 long stud method is the best due to unequal clamping forces which you are bound to get using 2 different types of fastener. i know several people who have had gasket failure on either no1 or no4 using this method. but at the end of the day everyone has thier own ideas on how to do things and its what works for you.

Rs Gus

iTrader: (2)

i have a tool to do that m8