Hitting on all eight cylinders
Group: Forum Members
Last Active: Yesterday
Posts: 7,
Visits: 181
|
Im working on building a mild driver 292 for my ranchero 4 speed 3.50 rear end manual everything. its mostly show but does do long trips. planning a 292 g heads mild port work, some form of longer tube headers 1 1/2 or 1 5/8, around 9:1 compression on e10. ive read a number of posts about y blocks, not needing extra exhaust duration, more lift less duration. i prefer a nice slow lopey idle over maximizing performance. i was looking at Oregon cams and have a few interesting ones that i believe could be decent choices. # .050 duration LSA lift overlap.020 dcr 791 230 230 108 .322 .326 52 7.51 34 250 250 107 .329 .329 74 7.08 807 222 222 109 .284 .284 52 7.34 346 234 228 106 .317 .319 45 7.75
How wrong was i in looking for a cam. #346 seems like a solid cam choice especially for lower mid performance, but would that cause super low rpm window? Does dynamic compression effect rpm window, would raising it on #34 improve performance of it while keeping in on 87 octane? for a lopey idle is it only the overlap that makes a difference or can less overlap on a narrower LSA have same idle as larger overlap on a wider angle. any suggestions where i can learn more, any free programs that would let me better compare these and their effects, other cams companies, grinds, or suggestions.
Thanks Seth
|
Group: Forum Members
Last Active: 6 hours ago
Posts: 158,
Visits: 117.1K
|
Hello Are you thinking new core or regrind. They (oregon cams) claims to have a original S/C EDB cam for pattern. I put one (RG) a stock 57 292,think with good your core around $100. Probably have timing events and lobe centers but know net lift .290. Ken (?) told me ) he thought OEM cams have better metal. Plenty of info it here.
|
Group: Forum Members
Last Active: 2 days ago
Posts: 1.1K,
Visits: 1.6K
|
When you say "clr", do you mean "LSA" (Lobe Separation Angle) or "ILC" (Intake Lobe Centerline)?
I've looked at a lot of Y-block cam specs offered/used by John Mummert (Clay Smith), Ted Eaton (Isky), Howard's Cams, and Schneider Racing Cams, none of which have more intake duration than exhaust duration. Most off-the-shelf cams have the same intake and exhaust duration @ .050; however, Ted has used split-duraton cams that have 228 @ .050 on the intake/238 @ .050 on the exhaust.
A narrower LSA (106-108) will give you the idle you're looking for without requiring a lot of duration.
If I were to choose one of the cams you listed, I would choose # 807 and use 1.54 rocker arms.
P.S. I'm wondering how #346/w 234/228 duration has the highest DCR of 7.75. Is it solely due to having the narrowest LSA of 106?
|
Hitting on all eight cylinders
Group: Forum Members
Last Active: Yesterday
Posts: 7,
Visits: 181
|
Black tie, I did mean lsa, not sure how my mind switched it last night when comparing. 346 had the highest dcr because it closes intake earliest. Also 102 lobe center. I was using wallace racing calculator. I have the 1.54 rockers.
Was also tempted by isky 301300. Been trying youtube to hear whats out there. Loved the sound from big mutha thumpr but theyre long since out of stock, and an area of contension across brands
Cos, Hadnt put much into new or oem core. Thats going to be their descision, id call and talk to tech support before final descion Seth
|
Group: Forum Members
Last Active: 2 days ago
Posts: 1.1K,
Visits: 1.6K
|
Unless you buy a camshaft from Isky, Howards, etc., it's most likely going to be a regrind. Several years ago, I bought a new camshaft from Schneider; I never used it and ended up selling it to someone on this forum. I've since contacted Jerry Cantrell (Schneider) about one of their other Y-block grinds. Schneider can't get new Y-block cam blanks, but will do regrinds. Keep in mind that regrinding a cam will reduce the lobe circle.
As the demand for flat-tappet cams decreases, getting quality blanks, particularly for not-so-common engines, may be a challenge.
|