like to know what intake valve to use to go bigger on the intake,same stock size on the exhaust. with smaller stems on both. and what vavle springs to use 125 seat 280-300 open with 530 lift cam. on 401-425 heads thanks
A couple of options here: http://www.v8buick.com/showthread.php?t=180715&highlight=stainless There was another post where someone had a custom set avail.... was it Gary in NY? or someone in the NW?
It was Gary Stevenson at ERD that built my engine that figured out the valves setup for me which has 11/32 stem valves. Click on the link below in my signature about the build post #77. "Valves. Manley custom 11/32 undercut stem. 1.92 intake. 1.550 exh. 305.00 full set comp cam behive spring which gives plenty of clearance at underside of rocker and is a very good quality spring $179.04. Comp retainers $50.40. Hardened 7deg locks $5.00. With mild cutting of the seat you end up with 120 seat and 290 open. Total cost for package. 539.44 plus shipping to customer." Erik
That looks good for the original intake guide ID, but if you're renewing the guides anyway you could go down to a 5/16" intake stem and improve flow a bit more. Collars and locks would be different. The exhaust stems are usually kept full-size to control temperature. Just remember: unless all parts are new and original, the rocker geometry is probably not 100% correct.
He was pretty tight lipped about giving away any part numbers or much information. I don't even know... sorry. And for the record, there were some modifications to get the springs to work. I am a little worried long-term about the spring pocket also had to be enlarged ever so slightly. If you notice there is not much clearace between the pushrod and the spring to begin with. I am going to be keeping a close eye on clearance/interferance issues there.:shock: Erik
You may already know this, but I thought I would share this experience. I have used small valve stem valves on some "brand X" builds in the past. On all of those builds, lash caps were necessary to maintain an acceptable contact "sweep area" between the valve tip and the rocker arm. Since the lash caps have a thickness, you have to plan for this when projecting final valve tip installed height. P.S. You won the contest for best 64/65 hood scoop. So, I picked up one off of ebay. Thanx for the inspiration!
That thread was modestly helpful. Definitely had valve options. close to nothing for springs, locks, etc. I hoped the experts would provide more information on how to do various options - very tight on information. good luck - let us know what you find!
tom t says he uses LS1/2/6 springs does anyone have the part # it sounds like you have to use longer valves
Here are the STOCK valve spring specs from an old Perfect Circle catalog. Perfect Circle Outer # 212-1119 Free Length: 2.070" Installed: 1.60" 43-49 lbs Open (0.440" lift) 1.160" 97-105 lbs Max O.D. 1.302" Inner # 212-1082 Free Length: 2.010" Installed: 1.69" 23-28 lbs Open (0.440" lift) 1.25" 73-79 lbs Max O.D. 0.920" Buick spec is 71.5 lbs Closed, 177 lbs open You should be able to look up replacement springs online.... Both Isky and Comp Cams have spring catalogs on their sites. I'm using Isky inners #1006-W with stock outers in both my rebuilt Nails.
#26125 Beehive spring from Comp looks like it would work: O.D. = 1.013" 130# @ installed height of 1.60" 272# @ 0.550" lift Might have to fill in the inner spring pocket in the head so the spring has something solid to sit on. I'm not seeing much else in Comp's spring charts that'll fit.... #988 double spring and #26995 Beehive both need the spring pockets cut larger....which may mean interference with pushrods.
.902 coil bind will that work with 525 lift cam i dont know how to figure that.. Walt i saw a 26915 check that out. buts its on a 1.80 installed height
Joe, take a look at the 'Valve Spring Charts' on pages 342-352: http://www.compcams.com/catalog/COMP2010/pdf/COMP_Catalog_2010_342-352.pdf Look at the pressure/ height chart and go from there. Stock valves have 1.60" spring installed height. Subtract 0.530" valve lift and you'll have 1.070" compressed height. Most of CompCams' springs won't compress to that 1.070" height, so there aren't many choices.... The 26915 spring won't compress to 1.050", so that won't work without mods....like longer valves, or cutting the spring pocket in the head deeper. You 'might' be able to cut the spring pocket deeper, but because of the pushrod, you'll have to decrease the OD of the spring to avoid interference. Tom may have been referring to the LS1/2/6 spring # 26918. It'll need a higher installed height to work. Ditto for the 26995 and 26981....need higher installed height to work.
Isky has a dual spring that'll give you the specs you are looking for: #1005-W outer with #1006-W will result in: 135# @ 1.60" installed height. 305# @ 1.050" compressed.....= 0.550" valve lift. OD is 1.32", which is just 0.020" bigger than stock. They might drop right in without any mods!:TU:
Bump! Anyone else have opinions on the ideal valve springs?? The Iskys look like the best drop-in replacements. Beehives have some performance advantages such as lighter weight, but lack the safety factor of having a second spring for back-up in case one spring breaks.
Installed heights can be played with using locks & keepers. By playing around one can achieve installed heights of more than 1.800" WITHOUT actually changing the height of the valve. Many options when not using original stuff. My recommendation is NOT to go any larger than 1.900" on the intakes if all else remains stock or close to stock.
