BenR
09-12-2005, 06:35
When you see claims of 200bhp with simply extensive gasflow work to the ports and valve seats, plus the superfluous bolt ons, you either call BS or pray that their work is sublime.
Not that many, or any of us have seen the cars themselves, but seeing the work is even more of a mythical myth.
A customer dropped off a cylinder head which he carried all the way over from the UAE in his hand luggage as his engine went pop. I was meant to repair the deamge on the cylinder head and send it off again.
To my horror i saw.
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020302.jpg
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020301.jpg
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020300.jpg
Hmmm........extensive port work, valve seat work?
I see, a ruined port, that isnt even symmetrical (unless someone tries to convince me that they are aming to create swirl for combustion efficiency lol) and totally std valve seats and valves. I wont go into details as it will bore, but suffice to say material removal was uneven, in the wrong places and in the wrong amounts. So the head became a rescue attempt to bring flow up to a std level, then continue on the minute details to bring it above std efficiency.
I was in a rush to get some pics before i flew out, so i didnt get some of the seats after they are finished or of the finshed head with ground face and cleaned chambers. But 16 new valves were needed, 4 were bent, the others were out of round from what i can only assume is poor valve regrinding, if they were even done at all.
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020318.jpg
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020319.jpg
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020320.jpg
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020321.jpg
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020322.jpg
And if your wondering why the exhaust ports exit isnt symmetrical, i didnt touch it......rather i didnt dare to. Right around the exit is a massive water jacket and its easy to hit, and this was already ground down alot, so i didnt dare risk it.
Sorry for the bore, but i thought it would be interesting to see other's heads.
Not that many, or any of us have seen the cars themselves, but seeing the work is even more of a mythical myth.
A customer dropped off a cylinder head which he carried all the way over from the UAE in his hand luggage as his engine went pop. I was meant to repair the deamge on the cylinder head and send it off again.
To my horror i saw.
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020302.jpg
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020301.jpg
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020300.jpg
Hmmm........extensive port work, valve seat work?
I see, a ruined port, that isnt even symmetrical (unless someone tries to convince me that they are aming to create swirl for combustion efficiency lol) and totally std valve seats and valves. I wont go into details as it will bore, but suffice to say material removal was uneven, in the wrong places and in the wrong amounts. So the head became a rescue attempt to bring flow up to a std level, then continue on the minute details to bring it above std efficiency.
I was in a rush to get some pics before i flew out, so i didnt get some of the seats after they are finished or of the finshed head with ground face and cleaned chambers. But 16 new valves were needed, 4 were bent, the others were out of round from what i can only assume is poor valve regrinding, if they were even done at all.
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020318.jpg
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020319.jpg
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020320.jpg
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020321.jpg
http://i13.photobucket.com/albums/a300/BenRAWT/renault/P1020322.jpg
And if your wondering why the exhaust ports exit isnt symmetrical, i didnt touch it......rather i didnt dare to. Right around the exit is a massive water jacket and its easy to hit, and this was already ground down alot, so i didnt dare risk it.
Sorry for the bore, but i thought it would be interesting to see other's heads.