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331 stroker... Q's about heads and carb.

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Old 12-15-2008, 08:07 AM
  #21  
urban_cowboy
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I am running AFRs 205cc racing heads with "supposedly" racing valves and springs. I have a roller cam and rocker setup from Comp. I checked with both Comp and AFR on the spring rates and everything matched up. After about 1500-2000 miles, I went to adjust the valves during a clutch replacement and found most of the valves are getting grooved on the tips of the valve stems. One of them was so bad it was about to kill the rocker. I called up the local AFR guy and he said yeh you need to run lash caps. The valve stems are soft and we have seen that more and more. I also talked with one of the local street rod builders and he said the same thing, but he has seen it from numerous head builders. Instead of buying Ferrera valves, we opted to just machine the tips and install lash caps. Ferrera valves are nice. I almost got a set of Titanium valves after this issue, but I was told they will kill your valve seats on a street motor, so instead of going with their stainless, I went with lash caps. That would have been MUCH cheap had we done that initially.

If I built this motor today with what I now know, I would buy blank AFR heads and build them out myself with Ferrera valves and may still put lash caps on. You cannot argue that AFR heads in the 351stroker sizes of 205 or even 225cc outflow most of the competitors in that same range. Their quality from a design side is nice, but I do not trust their valves and have heard bad things about their springs, although I have had no issue. I would check the springs before you build a motor out though, because my buddy ordered a set of heads for a flat tappet cam...It cam with roller springs and flattened his cam in a no time. After researching, they found that AFR had sent his heads to someone else. Again, build your own or triple check everything!
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Old 12-15-2008, 10:38 AM
  #22  
my77stang
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i'd like to know what valves afr is using but i'm guessing they dont say. i wouldnt doubt it if they were manley crap or some no-name offshore company. any decent valve is supposed to have hard tips which prevents what you had happen from ever happening, so really even the cheaper line ferrea's (or REV, which are excellent) valves would have been a great option.

also, with the hard seats used in aluminum heads i couldnt see titanium valves causing any problems at all, and would have been a great addition because of their weight which would let you rev a little higher without floating valves but they are expennnnnnnsive
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Old 12-15-2008, 11:22 AM
  #23  
urban_cowboy
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Originally Posted by my77stang
i'd like to know what valves afr is using but i'm guessing they dont say. i wouldnt doubt it if they were manley crap or some no-name offshore company. any decent valve is supposed to have hard tips which prevents what you had happen from ever happening, so really even the cheaper line ferrea's (or REV, which are excellent) valves would have been a great option.
No idea what valves they use, but they are definitely of the soft variety. I am running a 1.7 rocker which gives me an extra .04 lift, and I am running a 7000rpm chip in the MSD, but none of that should have trashed the tips. FYI, with the lash caps and about 700 miles so far everything is looking good. They are slightly noisier than without caps, but I still need to adjust the valve train again so that may go away.

Originally Posted by my77stang
also, with the hard seats used in aluminum heads i couldnt see titanium valves causing any problems at all, and would have been a great addition because of their weight which would let you rev a little higher without floating valves but they are expennnnnnnsive
They are cheap compared to pulling motors, pulling heads, machining heads, replacing valves, and replacing rockers! I think a set of Stainless Ferrea 6000 valves is about $250 and Titanium valves are about $400 a set. I spend that much just fixing this mess. That is why I say get bare heads and good quality parts, or go with lash caps (which are super cheap insurance).
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Old 12-15-2008, 11:30 AM
  #24  
my77stang
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yeah you just got a bum deal with the crap valves they used, and that's a shame. don't let it haunt you on any future builds. hell, i have almost 30 year old TRW valves in my 351w heads and after probably 10k miles using roller rockers and a .500 lift cam with 120lbs seat pressure springs there was no visible wear at all.
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