intercooling

[jontysafe]

I hadn't spotted the cracks, can you point them out?

Do I buy a new head or fix the existing one?

I will ask for pics of piston.

[jontysafe]

Just trying to work out whether i would be better off getting another head that's already ported to the same standard.

Need to find out head thickness.

Engine builder has advised fixing this one but will probably be about 800-900 squid finished ready for fitting.

[jontysafe]

Welding up of the three combustion chambers and taking back to standard again. Skimmed , pressure tested, new stem seals.

My head is has only ever had an. 8thou skim, most cossie heads out there are skimmed below where the head is actually jiggered.

[jontysafe]

Yep, includes cutting new valve seats.

[jontysafe]

Stevie do you reckon it will be ok to run 1.8bar on a 1mm oversize 200block or am I looking at getting it lined?

[jontysafe]

Thanks Max.

[jontysafe]

Much above 550-600 you would need liners installed like Ford did themselves with the wrc cars.

My block has some scoring on one of the bores so will need it taken out to +1mm.

It's a bit of a how long is a piece of string question really (block cracking) as it's down to the individual blocks and in particular wall thickness.

I won't be running hugely high boost pressures and as max says it will be mapped to keep Pmax as safe as possible.

Long term plan is custom tubular manifold and twin scroll turbo which will take it to over 500bhp to the point where gearbox integrity is more of a worry!

[jontysafe]

Apparently don't fit on 2wd mani, Mark Shead is trying a 4 wd mani next week.

I don't have room for 2wd mani, would have to be a custom made twin scroll mani.


Looking forward to a Ring trip in March.

[jontysafe]

It's not with Mark I've just been keeping abreast of what he is upto.

It will go to him in the future though.

[jontysafe]

Received today Cosworth Forged +1mm 8:1cr pistons, Mahle Motorsport big and main bearings, Cosworth HP 4x4 oil pump, WRC head gasket and top and bottom gasket set.

Should get things moving along.

[jontysafe]

Grrrrr, got everything apart from the pistons, 7-8 week wait time.

Now do I wait or buy Wossner instead? Cosworth world don't seem to rate them.

[jontysafe]

Everyone seems to use CP in high spec builds. I had Wiseco in before and they were pretty good, ie not too much rattling when cold and they actually stood up to the det ok as well.

CP are bloody expensive like £780. I liked the idea of using cosworth racing pistons, have a very good rep and a damn site cheaper.

People say the Wossners rattle a lot when cold but I'd have thought that would be a too wide piston to bore clearance?

[jontysafe]

Evoluzione said:

I'm presuming you've spotted the cracks?

It suggests to me that major overheating of the exhaust valve and seat area (the causes of that are numerous) has brought on det, i'd be interested to see a pic of the piston, if you can, hopefully you can also tell us which way round the crown was in relation to the head.

It seems you do have eagle eyes.

Cracks between valve seats, engine builder says he can fix but could cause probs in future.

Now looking for a good 4x4 cylinder head.

Anyone help?

[jontysafe]

Thanks, I will bear that in mind. This is another pic of the crack. Head has been at Grace Engine Developments and they have come back with "I wouldn't use that head for boost, you`d be flipping a coin every time you went out".

To be honest I don`t want to be constantly thinking when is my expensive engine going to fail. Again!

What`s everyone else's thoughts?

[jontysafe]

does seem a miniscule crack doesn`t it!

I don`t know enough to make a judgement so I can only go on their advice. I can kinda see where they are coming from; the most reliable engine wouldn`t have a cracked head.

I have sent pics to same chap that did the port job for a repair quote.

[jontysafe]

As far as I can see, just that one.

They have said it would be fine for NA but not sticking 2 bar up it!

[jontysafe]

Thanks for your replies guys. I`m going to call Julian Godfrey and maybe drop it down there.

[jontysafe]

stevieturbo said:

As said, contact some of the big name Cossie people

Harvey at SCS, Mountune, Julian Godfrey

they would be able to tell you for sure, or repair if need be

Or I seen Frosty used this place for a massive repair a year or so ago albeit a 2v head

http://cylinderheadservices.com/

I'm sure many of the cylinder head specialists could work with it too.

I really cant imagine the head would be considered scrap because of that little crack

Just search youtube etc for videos about head repairs, you'll be amazed at the work that's done

thanks Steve, have rung these guys and sent a few pics over. Waiting for a price Monday.
If they can put valve seats in Red Victor I'm sure my car won't be too much of a problem.

[jontysafe]

They reckon it can be fixed and will warranty it for 12 months! It's on its way there now. Thanks for the heads up again.

In the meantime have been offered a minty fresh 4x4 standard head which I think I'll buy as well.

[jontysafe]

A small update as not much progress been made. Decided not to fix the current 4x4 head as it was going to end up under 138mm head height. Would have been throwing £1200 at a head very much on its last legs. I have another 2wd head on 138.5mm which I will probably use. Bassett Down Balancing have been given a contract to balance electric motors so we have now given the job to Grace Engine Developments. James there has built some very powerful reliable Cosworth YB engines so feel in safe hands. We did talk about going mad and doing a 2.2 stroker with a Borg Warner twin scroll turbo and 600bhp but maybe slight overkill!
Looks like we are going to do a nice road engine circa 450bhp, maybe longer rods and custom cp Pistons. Probably going to go Link ecu. Have asked for the engine to be done by June but best laid plans and all that......