i am looking for a cam for a 350 sbc i am putting to gether. the engine is basicly stock about 8.5:1 compression but will have an aluminum intake , 600 cfm edelbrock carb and good exhaust. i like the sound of gm's 290hp crate motor. the cam specs are 250/260 114 lob cent. can you buy just this cam from gm ? who makes about the same thing ? what cam are you using? i want some ruff idle but to way over board.
Rv towing cam would work good , If for a rod.What gear ratio and converter or trans are you using......
i just bought a cam for the 602 crate and it cost me $141.00 all the parts for the crate motors are available it's just some dealers can't be bothered looking because they aren't listed in their internet parts list they use everyday and some parts are tooo expensive,even if you have the part number the might have to call GM because it's not listed.
This is a very good cam, I have used it in two sbc. Awesome power and great sound. It reacts very well w/ mild upgrades( carb, intake, headers)
other than this cam and a set of new lifters and a new timing chain, do you need to do anything else? like head work? machining? what spring or will stock spring work ok? thanks for any input. i am not much of an engine expert.
No machine or head work needed. I used the stock springs with this cam and had no problem. I used roller rockers also bit you don't have to. This one of mine was in a 48 chevy pickup. I know this doesn't mean anything but you could bring it down to 1st (th350 3:42 gears) rolling on the street with no brake and stand on it and it would jump up to about 5k and bump it to second and it would enilate the rear tires. It would be an awesome cam for a 3- pedal car. Mine had low end grunt but would spin tight and it felt comfortable in higher rpms just as it would if it were cruising. '78 350ci stock bottom end with new rings and bearings, fresh stock heads, 274h cam and lifters, comp cams roller rockers, cloyes double roller timing set, single plane intake, 600 Edelbrock. And Sanderson block huggers. This was my combo . Feel free to ask any more Q's.
.490" lift at the valve, you do need a better spring. Even Comp recommends it if you dont want to believe me. No machine work, but the 1.254" O.D./.880" ID springs at least are needed. With that lift you also need to check for rocker stud to rocker arm clearance{ ie long slot stamped rockers/ or roller rockers }, as well as the pushrod length { geometry}. Dont take a .490" lift cam lightly, yes there are so many who have just bolted it in and ran it, well good for them. .450" lift for a SBC is about all you want to go with all stock valve train componants, and not checking anything. Anymore is pushing your luck, I dont care who you are, unless all you do is back it off a trailer once a week. TR
The Summit 1103 cam is very close to the 290hp crate motor. I have the crate motor and another motor with the 1103 and spring kit. Same idle characteristics. I am running a 650 Edelbrock on the crate motor and a 600 holley on the other one. I don't think your cam specs are right for the crate motor. I will double check. cam: http://www.summitracing.com/parts/SUM-1103/ cam and lifters: http://www.summitracing.com/parts/SUM-K1103/ springs: http://www.summitracing.com/parts/SUM-174001/ Crate motor specs: " The camshaft has .450" intake and .460" exhaust lift with hydraulic flat tappets." The cam kit from summit includes lifters. I am running 700R4, AC, and power brakes with no idle problems. This should be a consideration for you in cam selection for idle vacuum. The 1103 has 11 inches of manifold vacuum at idle. The crate motor is slightly higher.
Some factory 350's came with .450 and 4.60 valve lift, mostly in corvettes. Not trying argue but I had no problem with mine at all, it never seen a trailer and drove it all over. if I remember right mine might have factory spec z28 springs if there is a difference.yes I did just bolt it in and run it because i have done so many times on other engines with never a problem. An rv cam will not make much sound and k think you will be disappointed, but that's my 2 cents. Different Strokes experience talks bullshit walks
Pioneer Z28 springs would be acceptable, but double check. This would be the cheapest route besides the Summit springs. Z28 springs should be around 125 pounds on the seat, 290 pounds at 1.4.
The 268h cam has .456 lift. Won't he Need to upgrade all of his valve train? If .450 is all you wanna go with stock valve train.... Again not trying to argue I just want to better understand
I'm running a Comp Cams Dual Energy cam. Its .462 .482, can't remember the duration right now. I think it was around 270. Only thing I had to do was put screw in studs and pushrod guides in. Sounds great and performs as well.
If youve got the extra bucks, and it doesnt take much, do yourself a favor and score a good set of 305 heads #14014416 valve job and z28 valve springs. I have had great luck with this combo on top of 350s for street and circle track. Bumps up the compression, no probs spinning to 6000 rpms. And I have no probs up to .500 lift, and never checked a damn thing, (dished and 4 relief flat tops). Bit more compression and you can drop the lobe center to 110 or 112 which equals more lope, but a bit less leaving the stop light, (but IMHO you wont have a prob with your car/trans/diff combo)
Willy, I apologize if you think my rant was meant for you, it wasn't. Not meant for anyone here. I just like when fellow HAMBers do things right and not try and cut corners. Lots of folks get by with the big cam deal, others dont. When the rocker arm slots are not quite long enough for those cams, the damage isn't noticed for many miles, but its happening. The studs get cut into until they fail, and all the while the metal is going through the engine. Sometimes it last's for a few years, but it is destroying itself slowly, and it's wrong. The Z-28 springs are not your typical replacement SBC spring. They have the dimensions just like that I gave, and require no machining just like I said, they are a good upgrade. You had both the Z28 springs and the roller rockers, so you had a pretty good and non-stock set-up. Not changing the pushrod geometry is another area, that MOST get away with and dont have any issues at all, doesn't make it right though. I dont think the original poster had this much work in mind, and I got a little rough explaining how to do things 100% correctly. There is a huge diffrence between a crate engine and the race engines I build. Most folks cant afford to even just have me blueprint a set of heads for them. Again, I apologize the rant was NOT directed toward you or anyone else, THANK YOU, TR
As mentioned above,a Comp 268H would be my choice considering Coupe DeVilles initial post. Break it in right with new lifters,change the oil & your'e good to go. How heavy is the car?
I appreciate all the info and understand now it wasn't directed toward anyone, I don't know everything and am not an engine builder but now have a better understanding. If you don't care I am gonna pm some questions in a bit. Thank you - willy
I sent you an apology and explanation in my other post. That said, please understand I didnt say YOU MUST REPLACE all your valve train, but I did say you should check everything. Willy, remember we live in a white-box world now. If you dont know what we mean by that its this, almost EVERYTHING comes from CHINA. Regardless whether or not your building a $60,000 race engine or a $1500 claimer, with the white box parts, you need to or should check everything. Even a mild build, it's just good insurance. Now as far as the .456" lift or the .450" lift, that's .006" is not the point here. You know that. Hydraulic lifter plunger travel is about .100"-.120"., and when you adjust your lifters you are generally setting the plunger down between .040" and up to .080". So again, we are not nit-picking a few thousandth's here, it's not that critical, but for the guy who has never done this before, better safe than sorry. That;'s all I'm saying friend, have a great evening, TR
Thank you for understanding, I have to step out now, as I have a Doctor appointment in the morning that's real important. I'm trying to get the O.K from him, and to start the shop again and build some Nailhead Buicks. People are driving me bonkers to build for them, and I need it for myself, keeps Mama happy too!! TR
Throw on a pair of vortec heads and some shim head gaskets. On the dish piston shortblock and you would have a potent daily driver with plenty of usable pep.....lolhalf tempted to do a cam swap in my coupe to the one mentioned....
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