Hello fellow Hot Rod owner's. Picking my cam for my SBC 327. I'm looking at the Howard's #11257-1-12= 215/225 & 455/465--112LC//108°CL--rpm 1200-5500 OR the Edelbrock #2117= 218/224 & 464/470--114 LC-- rpm 1000-5500-- What CR will these two cams need ? My second 327 I'm building is a 1976 350 4 bolt main block .030 over-with a 327 LG crank/-5.7" Rod's/- pistons #KB156.30/ -Heads #461 milled 1.94/1.50 valve's- with Z/28 Valve springs/- Steel shem head gasket .015/- Block was Not milled factory .025-.029?? -- Eddy C3BX with 650 DP Holley/- Factory dizzy/points/-- Rams Horn 2 1/2"/-- What's the minimum CR the above Two Cams can run correctly with?? For my 68 C10 pick-up short box/fleetside- 3:73 gears and 3 speed Standard-- will my 327 have enough CR for either cam? What would be the better of the two?? Street only truck. Thank you again for your help and time. From 1Nimrod
Well I'm not the engine expert of others around here, but it seems a bit like you're putting the cart in front of the horse. Shouldn't you be picking a cam that works with your compression ratio (and intake/exhaust & rear gears) rather than picking a compression ratio that works with the cam? As far as compression ratio, if it's a street truck you have to live with existing fuel quality. If it's a daily driver you probably want to keep it on the mild side to avoid having to use premium fuel, to keep your costs down.
With the 108* lobe separation on the Howard cam it will bleed off more compression because of the greater overlap. If you are looking for a racier sound at idle then go with that one. The Edelbrock with the 114* lobe centers will have more dynamic compression (less is bled off) and also produce more manifold vacuum because of it’s more stable idle characteristics. If it was my engine I’d be happy with an honest, computed, 9 or 9.5-1. I think your choice of the C3BX is a good one, there are better manifolds but the C3BX has the “look”.
Fordors gave you good advice. Don't be afraid to call someone like Comp Cams and tell them everything you want to happen. Most of the cam companies want you to be happy. Age and exp. tell you that you can't have everything.
When your done, find an overdrive 3-speed trans for it. U don't need to make it all stock with kick down and all.
Thank you for your help, I like the old look of the Eddy C3BX, I'm trying to keep the engine mid to late sixty looks like when I was a younger man way back when in high school. I'm open to other cams that will match my engine an truck that I've listed. No rollers. Thanks again for all the help and suggestions from 1Nimrod
Fordors could you give me two or three good excamples of honest computed Cam's for my 327 that I mentioned above? I do not want a cam that bleeds off any of the CR, also no roller cams and no solid lifter cams. If possible I'd like a good street performance cam with split intake and exhaust on the Lift and Duration. Would a cam with a Lobe Separation of 107° intake and 117° exhaust be just like the Howards cam and bleed off the CR ? Any information suggestions and help will be appreciated. Thank you again for all your help and time. From 1Nimrod
A cam with a 107* LSA is going to be pretty lumpy. You have an advantage with the 3-speed and 3.73 gears, what is the 1st gear ratio? Take the 1st gear x the rear and somewhere close to 10 is a good number. You don't want the thing to bog when you let out the clutch. I run a 2.52 1st with a 3.89 rear, I'm up around 9.80. You should also know with some certainty what the static CR is. Read some cam specs and some will have a minimum CR recommendation, also a minimum carb CFM rating.
When I read your question the first time I made one critical error, I misread the specs you typed and thought the lobe separation angle was 108° when in fact you said it was 112° and that changes things. At 112° you will still have a decent idle and vacuum with the Howard's cam, but in checking the Howard's listings I don't see a 11257 listed. If that part number is correct it looks as though the effect on your compression would be similar with either of the cams you originally listed, they will both have minimal overlap. In Post #10 you are confusing lobe center lines with lobe separation angle, and in my initial post I also used both terms as if they were interchangeable. I should not have said "....114° lobe centers...." talking about the Edelbrock cam, but instead 114° LSA. Your mention of a cam with a 107° C/L on the intake at maximum lift and 117° on the exhaust C/L, and adding them together is 224°/2 equaling a lobe separation angle of 112°. Again, a cam with 112°-114° will easily be streetable with a decent idle and vacuum, and I think the KB pistons and '461 heads will give you somewhere near 9 or 9.1-1 compression.
bobSS396; Not sure what my gear ratio is, I have what you call a peanut gear box. It's the four bolt side plate tranny original to my 63 C10 pick-up M318 I believe. The cam I was referring to was pt#MC1730 Duration @ .050: Intake:204/Exhaust:214 Lift: Intake:420/Exhaust:442 Lobe Separation:Intake:107° Exhaust:117° My CR is around 9:25.1 Thank you for your help. From 1Nimrod
Fordors; The Howard's cam is Part # 112571-12 The other cam is pt#MC1730 Duration @.050/Intake:204/Exhaust:214 Valve Lift @.050/Intake:420/Exhaust:442 Lobe Separation: Intake:107°/Exhaust:117° I have the MC1730 cam in my other 327 it's CR is maybe 8:5.1? it's going in my 63 C10 pick-up and I'm wanting a bit bigger cam for the 68 C10 pick-up. My CR for the 68 C10's 327 is around 9:00.1 to maybe 9:25.1? I don't want to over cam my 327 but I also don't want a Grandma's cam eather (I already have one in my 63 C10 pick-up). I'm trying to get some sound advice for a better street cam. I appreciate everyone's help and time,Thank You again... From 1Nimrod
Your LSA is 110*...its just advanced 10*(107intake-117 exhaust) IF...it was ground "straight-up" it would be 110* intake and 110* exhaust. Lotta cam companies GRIND their cams with advance in them. Because most guys over cam their engines and by advancing the cam.....it gets back some of the lost bottom end/sogginess. Jus say'in 6sally6
jimmy six; I picked up a auto column for my 68 and cross member and other parts to some day convert over to auto but I'm not going to convert over for some time but thank you for your reply. From 1Nimrod
6sally6; That cam is in my 327 it's going in my 63 C10 pick-up when I get all my other parts together. The machine shop put it in straight up the cam maker said that's the only way to do this little cam. But I think your talking about something different and I don't know that much about the technical cam talk, I'm older but in the dark that's why I'm asking for help on choosing a cam for my 68 C10 pick-up's 327, It's built better than my 63 C10 pick-up 327. The 68 C10's 327 has just a little more CR so I want to go up a few more steps in the size of the cam. So I'm reaching out to fellow HAMB friends for help on choosing a better cam for the 68 C10. As I stated in the other posting I'm open to suggestions. Thank you for your help (even though it was confusing to this green old man.) 1Nimrod Gen10:9 A mighty hunter before the Lord;
1NIMROD, I am going thru a cam change myself. There is a good thread on it here. I, like to you, am no expert on cams, just wanted a bit more umph out of my bored .283 with an L79 cam and other changes. Lots of questions asked that I could not answer...most good questions. Best thing I did was call Comp Cams help line.. Unfortunately had to wait and listen to their horrible music for over (20) minutes, but when I finally got a tech on the phone it was worth the wait. Very helpful as well as knowledgeable, and as a result I ordered one from them. I also talked to one other cam manufacture. So my advise is to pick what makes sense out of this thread, and by all means DO call a tech from a cam company. Good luck, my cam will be going in early next week..
Delta Cams is my go-to guys(ask for Ken) Good guys-good prices-quality stuff! Can't remember what kind of tranny you have or rear end. Prolly the gear is low enough to give plenty of bottom end. 230-236@050 Duration 108-110* LSA 450-470 Lift I bet these specs would work pretty good in your 327. Not too radical but better than the old 327 cam you have now. Wayyyy newer design better power and not hard on your valve train. Picking a camshaft for somebody else is like.......... 'me picking out underwear....for you to wear'! 6sally6 Wasn't Nimrod a fallen angel?!
6sally6; thank you I don't think I'd like anyone picking out my underwear they might pick out Pink Rose's or one of them rubber band cup thing's... But back to the cams... Thank you for your help I'll try and find that cam company and call them and see what they have to offer. And no Nimrod wasn't a fallen angle. In the Bible people's names translated into what they did in life like there jobs or work's. Jesus name in Hebrew is Yeshua and that translates into Rescuer, Deliver, Savior... Jesus is our Lord an Savior... In Genesis 10:8 & 10:9 it reads; 8)Cush was the father of Nimrod who grew to be a mighty warrior (hunter) on the earth. 9)He was a mighty hunter before the Lord; That is why it is said like Nimrod a mighty hunter before the Lord; Nimrods name means "Mighty Hunter". Nimrod was a ruler of many kingdoms. (I use the name Nimrod because a dear cousin of mine called me "Nimrod" many years ago, because "I'm a Hunter") Thank You again for all your help. From 1NIMROD
Hdonlybob; thank you for the advice, I hope you like your cam when you get your vehicle put together. And God Willing I'll find the cam that will fit my trucks personality and my driving habits. Thank you for your help... From 1Nimrod show me some pictures of your engine when you get done. Thanks again... 1Nimrod
sdluck; I've never seen that Cam company name before 6sally6 also mentioned that company and so do I just go by "Delta" when looking up there information? Thank you from 1Nimrod
sdluck; Seems the Delta Cam Company is up for sale all I could find was a few reference to other cam companies like comp and to summit for cams I'll try again tomorrow and call this time. Thanks again from 1Nimrod
Give Bullet Cams a call. They will custom grind whatever you need. They will walk you through it also. Don't have to be a cam expert, just tell em what you are after. http://www.bulletcams.com/
Sorry for the late answer....I just got my car back last week.. Extremely impressed with the difference...and now very glad I did it.. Was it worth the cost ????? Maybe, and maybe not....but I like it and am happy. Here is a picture of my little "Engine that Can" Hoping you are finding one that will suit you as well.
If it was my truck I'd go with an XE262H-10 Comp cam, lifters and springs. It barely has a little rumpety-rump and lots of torque. It will go nicely with your 3:73 gears. http://www.compcams.com/Technical/DynoSheets/XE262H-10_001.asp
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