This is precisely why I will never be rich. I should print out this post so in the years to come I can show to my kids when they ask daddy where all the money went....

 

To elaborate on EVOlutionary's response, you need to think about how the heat is getting into the valve. During the combustion process all valves are closed, meaning only the bottom face of the valve is exposed to the hot combustion gasses. Both intake and exhaust valves are put under the same thermal stress at this point. However, when the exhaust valves open the exhaust passes by the top of the valve seat and the neck of the valve, exposing a much larger surface area of the valve to that heat energy. That increased exposure is what makes the valves hotter and more likely to "burn". When the intake valve opens, just as EVOlutionary said, they are cooled by the intake air that passes over the face and neck of the valves.

- Steve

 

funny you should say that.... looks like i might be building that same setup.


Jun stroker on the way. gt35r and full-race manifold


deciding on the head, but it looks like i might go with the cosworth head.


just dont know a lot about the valvetrain components. Cosworth makes quality stuff.

but will it be better than a head coming from one of the top head work guru w/ ferrea (proven time and again quality stuff)??? thats the question

id hate to be one of the first to try these and lose a motor.

 

mase when did u get a EVO?

 

I think Cosworth has been proven time and again and again and again and again to be very high quality stuff.

- Steve

 

I still want to see some flow numbers or more head specs on this head. $3800 is a whole lotta money. I'm not questioning cosworth's quality, or their ability to make custom race and oem applications. But my experience has always been that the big name companies tend to make off-the-shelf products with similar performance value to what's on the market, only they have possibly greater quality materials and name cache$$$. I would be surprised if these heads produce significantly more power than what has been found on re-worked heads in the market today. For roughly twice the price, I hope I'm wrong.

 

this is very true... but there is that ease of mind factor. they put it together right nad with something like a high revving engine... that matters. now how much htat ease o mind costs or i worht is a whole different issue.

 

Plus you need to look at it from a real cost standpoint.

Comparable head... AMS Race Head $1850, plus you need to send your head to them for the work to be done.

Cosworth head $3800 but it's a whole NEW head.

How much is a NEW head from Mitsu? $2000

$2000 + $1850 for AMS's work, you're at the same price.

Just some food for thought.

- Steve

 

if there is one thing that you should spend good money on from a quality manufacturer like cosworth, The head is really worth it. There is nothing like a properly manufactured Head, ported, polished, and clean. I would definately get it if they had one for the IX.

 

That head is crazy. Everything Cosworth makes is top notch quality. I can almost guarrantee you won't find a better head for the 4g63.

Even their pistons are highly engineered. They have 20% less blowby than any other piston designed.

With that said, screw a turbo kit, I'm buying this head.

 

right, and i want one!

 

I have one on the way along with a 2.3 shortblock from AMS. Hopefully it will all be ready in a month or so....

 

I had a Cosworth 1.8t on my Audi S2 and can vouch for their quality.
Cosworth is pure integrity.

 

John at RRE has been running this head on their race car. He says this head doesn't even compare to a standard ported head. THey're not even in the same category.

 

I wonder if the new Cosworth block will be aluminum with iron sleeves? That could be worth some real weight savings off the front of the car...