Well, finally we have some progress. The new cylinder head is done. I should be collecting it today. The engine is in bits and hopefully will be re-assembled this week.

I just need to decide on what combination of head/bolts to use as we are in fairly unknown territory.

1. Standard Head Gasket - Standard Head Bolts

2. Standard Head Gasket - ARP Head Studs/Nuts

3. Cometic Head Gasket - ARP Head Studs/Nuts.

Answers on a post-card please!!

I would almost ALWAYS suggest Standard kit to people, but we are looking at 350+bhp here, do I still go with that??!!

I am unsure of the reasons/problems caused by the above combinations as the engine obviously has a Cast Iron Block and Alloy Head.

 

Your the Tuner lol, you tell us

Sorry im no help

Steve.

 

well have you ever had a std one fail on you on a fairly new engine before? i'd still go with std every time (seems the most reliable to me)

 

Thanks.

Trouble is, how often do we see a genuine 350bhp CVH RST??!!

The only gasket I have had fail is the Cometic. That has been the ONLY failure I have had in all the time I have owned the car. But we still don't know if the gasket was the reason.

I am inclined to go for the standard gasket, I guess this is more about whether to use the standard stretch bolts or the ARP's.

 

Std Head, std bolts.

Why would you want reusable head studs? The standard items are stretch bolts, and give a constant clamping load as the head and block expand and contract.

 

2. Standard Head Gasket - ARP Head Studs/Nuts

As you've said, the standard gasket hasnt let you down yet and the ARP studs/nuts are that little bit stronger at keeping everything together so i'd go for that combination. Seems the best option imo

 

Id suggest a Ferriday copper gasket with stud & nut kit.

 

I have a similar setup, and I have never had a single bit of trouble with ARP Stud and Nut kit with Cometic Head Gasket.

Hope this helps

JJ

 

Well, i'd rule out a cometic...it did fail....can you risk using another incase it was the gasket at fault?

Standard one has never failed, so i'd go with that! its wether to use std head bolts or the ARP lot.

 

I would also use std gasket and arp as the bolts are a little stronger.
BUT i would only use arp if u are an topspeed geek, otherwise keep the std bolts also

 

how do you not know what failed again - cant remember reasons?

 

We don't know if head gasket went, which caused the rad to fail or if the rad failed causing the head gasket to go.

No real way of knowing.

There was a chunk out of the head too.

 

i remember a post now with the end can off the rad i think. hmmmm decisions lol so you think it pressurised the water way? If the rad has gone first things usually get very noisy and seize from heat - thats what you usually see at knockhill when someone has a water leak - you then have a bet on how many laps they will do - next time round they just get slower and noiser so my guess would be your HG went first on this thinking? would the head not be warped etc etc from running mega hot for a period etc as well. If your radiatior blew 1st i guess you may have shut it down before anything else died around it? thats my guess especially if it was knacked enough to lose a chunk of head in the process. I have seen water pipes blew off on full bore with no damage and its pretty obvious when it happens!!!

 

The head has been fully repaired and alignment checked.

I'm still with the idea that the head gasket went first, I shut down VERY quickly and I am VERY aware whilst doing top speed runs. I heard a loud crack, which was either Det or the rad blowing and that was it.

We think that once the gasket material had gone, the head was eroded very quickly by super-heated gases, just not sure in what order everything happened.

 

If the mating surfaces are correct, and the gasket is installed properly, there is no reason why it should fail...... I was running a relatively high boost engine, doing a lot of heavy use and no problem with the gasket at all!

JJ

 

as for you gasket choice - who knows lol - i vote std gasket on wire rung block, std bolts. As long as who ever wire rings it has good experience of doing it and feels its a good choice - eg they have done lots and seen no failures from their own installation as i am sure the quality of job can vary amazingly given the process and how simple it seems!

but then again you are looking for people experienced with 350hp CVHs lol - what do tommy field and norris do?