2003年4月15日 · The 1974 and earlier SB Chev heads are the ONLY good heads in regards to PRODUCTION heads. This DOES NOT include the over-the-counter performance heads (i.e. Bowtie heads). In 1975, Chev began cutting corners on their SB heads by casting them thinner is some areas and completely eliminating metal in some areas.

2012年5月5日 · I had a set of 487X heads on my '73 Hatchback Custom 20-something years ago, which I *think* were factory heads that came with the car. With a TH350, a Weiand dual plane, a Holley 600, a 350-horse cam, dual glasspacks, and some VERY light springs in the point-type distributor, that car would schitt and git!

2005年1月1日 · Hey, i dont know for sure on anything but i have 2 pairs of 487X heads. I use them on my circle track car and they seem to perform much better than most other stock heads....from my experience the 487, 487X, and 441, 441X heads are the best flowing. both pairs of my 487X heads came off of corvettes. both pairs of 487X have the 1.94 valves.

2007年6月26日 · I have decided I want to keep it period correct as much as possible with a mildly modified stock appearance which means my Vortec heads and Performer intake aren't going to fly. I picked up a set of low mile 487X's in very good condition and have a friend with all the equipment to cut them for 2.02/1.60 valves and install hardened exhaust seats.

2006年12月28日 · Thats your basic early 70s 1.94 -1.50 valve head with 76cc chambers. They are one of the better 76c heads similar to the 993-441 .

2013年9月2日 · Hello, this auction is for a pair of completely assembled aluminum small block chevy cylinder heads. These heads will fit all 262-400cid engines from 1955 through 1999 and are nearly identical to ProComp Motorsports heads part number P3002S. The heads have provision for either center bolt or outside bolt hole valve covers.

2011年5月9日 · Just my opinions, but I would be very surprised if the 487x had any meaureable difference with a regular 487. Personally I dont think they are all rare either. The "X" head that I have seen that is better or rare are the 461xs. I would say (for what its worth) that either of the 487s are probably my favorite of the early tapered seat spark plug ...

2012年1月12日 · 487 heads i have a set on mt 350 except mine are 487x been looking for flow numbers cant find any not even on stan weiss, im thinking they flow close to camel humps somewhere around 215 intake at 500 lift.just using what i have for now, so if your budget permits go newer cause a set of vortec flow stock around 225 at 500 lift.

2011年10月3日 · I had a set of 487X heads on my '73 Hatchback Custom 20-something years ago, which I *think* were factory heads that came with the car. With a TH350, a Weiand dual plane, a Holley 600, a 350-horse cam, dual glasspacks, and some VERY light springs in the point-type distributor, that car would schitt and git!

2003年8月29日 · 487X heads are a fairly rare find....they came on early '70's LT1 350 engines.....being a "X" casting, the intake ports are 10cc bigger than the standard 487 heads. They might already have 2.02/1.60 valves too. The combustion chambers are 75cc's though, so if you want high compression you would have to run a domed piston.