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Quick question guys. I have a set of heads (305ci 416 castings) that I am getting ready to replace the springs on. I was told that the Exhaust Rotators would not hold up to stiffer springs. I know they make eliminators to take their place. Is this a wise idea? They were put on these heads to rotate the exhaust valves but will I see any harm by not using them? The car will be 90% light to light and 10% track.
 

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rotators

I have rebuilt dozens of ford and chevy engines with the rotators and those without. I have never been able to see any advantage to them. I always leave them out for any kind of performance use. I know most high performance factory engines do not use them.
 

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Use same retainer that is on intake and use .090 worth of shims on bottom of spring. Theres no shortage of retainers and will cost you about $5 for some spring shims at any automotive machine shop.
 

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Exhaust valve rotators

The rotators were installed to rotate the exhaust valves in an effort to reduce valve and seat burning and extend their useful service life. This was required when "lead" was removed from gasoline back in the early 1970's. The original reason lead was added was to increase the octane rating for higher compression engines. It had an added benefit in that after going through the combustion process, the lead coated the valve and head seats and insulated them from the heat of the exhaust gases. If building a high revving engine that is not a daily driver, I would recommend against using them. They seldom fail, but the results can be ugly when they do. For everyday driving on unleaded fuel, it will not hurt to retain them.
 

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meschnebly said:
Quick question guys. I have a set of heads (305ci 416 castings) that I am getting ready to replace the springs on. I was told that the Exhaust Rotators would not hold up to stiffer springs. I know they make eliminators to take their place. Is this a wise idea? They were put on these heads to rotate the exhaust valves but will I see any harm by not using them? The car will be 90% light to light and 10% track.
Most small block heads have a short spring on the exhaust, so to make regular springs work, You need to get you some regular retainers, to replace the rotators, when you take the springs off look at the length of the intake versus the exhaust to determine this.
 

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dgcantrellsr said:
Most small block heads have a short spring on the exhaust, so to make regular springs work, You need to get you some regular retainers, to replace the rotators, when you take the springs off look at the length of the intake versus the exhaust to determine this.
The short springs were discontinued in 1976 or thereabouts. I have 2 882# heads, one that is factory set up for the short springs, the other is factory set up for the long springs. As was stated, you HAVE to check the installed height no matter what retainer is used.

BTW, I used to use the H retainers (from mid-sixties heads) to shorten the installed height (about .040" less than the V retainers).

tom
 

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Discussion Starter #8
Thanks for the replies guys. I was told that if I used stiffer than stock springs that the rotators would fall apart and cause major damage. I've been hoping that I could remove them, shim up and just use springs without any problems. Did those rotators really do any good anyway?

Mike
 
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