what is the biggest cam i can put in a 350? [Archive] - Chevelle Tech

: what is the biggest cam i can put in a 350?


iwantachevelle
Sep 18th, 01, 1:22 PM
without having to do the whole valve train? i would like a solid lifter. what do you guys recomend for the most power from 2000-6000.? is there a cam like the 270 in a solid lifter? what is your opinion? tha moter will have a good intake, headers, holley 600 cfm vac. secondaries., and mabee some head work/

chev-hell
Sep 18th, 01, 4:11 PM
the cam can be as big as you want nearly but if it doesn't match the CR, intake etc. it's pointless and will run bad. if you want the most power get it to match what you have now. the 270h should have around 9.5 or so CR and they don't make it solid that i know of.

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1970 SS396 AKA 454/4spd
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Wally
Sep 18th, 01, 5:22 PM
This one is easy, get a cam for a 70 1/2 Z/28. It meets all your requirements, solid that will work with wussy springs, came in the 350 motor, still available from the chevy store or almost every cam company. Needs a little compression, 3000 coverter if it's an auto. Cam has 458/484 lift.

?
Sep 18th, 01, 6:00 PM
If it's not gona be a insanely high revving motor why not go with a roller so you don't have to hear that annoying ticking?

What compression is your motor? Also, you might just want to buy a good set of heads instead of doing work on the ones you already have.

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kenny

85 El Camino 355ci
350 turbo - 4.11's
best run so far 12.92
My Page (http://kenny350ci.hypermart.net)

iwantachevelle
Sep 18th, 01, 7:02 PM
the motor is out of a 85 blazer so, i guess it is 8.5 cr? i would like to buy a kit from summit with the lifters included, and mabee the timing chain. the motor is not going over 6000 but cost is a factor, so i like the solids.

chev-hell
Sep 18th, 01, 8:46 PM
well keep in mind that you will probably over-cam it with your mind set http://www.chevelles.com/forum/smile.gif bigger isn't necessarily better in all cases, it's probably an 8.0-1 CR, which does not alow much for a cam, but you can bump it up to the "z28" cam and the springs are cheap too and ez to come by. they have around 120lbs. of seat pressure.

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1970 SS396 AKA 454/4spd
My Chev-Hell Page (http://hometown.aol.com/jnkb2cool/home.html)
GOLD Member #783
Ft.Worth, Tx
Big Block Chevy.net (http://www.bigblockchevy.net)
proud owner of this site
(OO=ss=OO)

Bomber '67
Sep 18th, 01, 10:15 PM
I just love it when a young man dreams of speed and glory behind the wheel of his automobile http://www.chevelles.com/forum/smile.gif

Somehow it is always the same couple of things that budding gearheads always think of when it comes time to dream BIG; camshafts and carbs. Hey, I did it too once upon a time; "lets see how that 850 double pumper will work on my 283" - oohh, what a bad idea that was (but the lesson was learned).

Let me introduce you to a different way to think BIG. Instead of merely the size of some part or another, think about how to make BIG cylinder pressure. There are two main directions you can go: by force, or by increasing volumetric efficiency. By force would be nitrous, a blower/supercharger, or exotic fuel like nitro. Increasing volumetric efficiency covers just about everything else, including your desired camshaft upgrade.

What others here are trying to tell you is that you can do what you want, but you might not get what you seek.

You really do have to keep in mind the parameters of the total car/driveline combination, otherwise you will face dissatisfaction. When doing mods you may seek out BIG, but you must not forget compatability. For example with the camshaft: let's say that you put in a nice rumpity rump gring with 110 degrees or less of lobe separation angle (shown as LSA on your cam spec card), problem is that your 8.0 to 1 compression engine wants 114 to 116 degrees LSA. The 110 degrees or less of LSA of the rumpity rump cam needs 10.5 or greater compression ratio to work properly (just like the old musclecars came with from the factory).

So keep in mind the rest of the driveline/car combo when selecting upgrade parts. In your case with the low compression you have I would reccomend looking for a solid or hydraulic cam with a little less than .500 lift, but with a wider LSA in the 114 to 116 degree range to keep the cylinder pressure up.

Best of luck, let us know how things turn out, Thomas.

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"Bomber" '67 El Camino, Beater comes back to life.
Was 350/TH350 14.90 @ 93mph, 360,000+ miles on car
Now 406 roller, 340rwhp, more hp coming, 3.08 gears
Street radials, left in drive, 13.20 e.t.@108.35 mph
8/1/01 added Plum Mist '67 to collection
*New* 468 on its way - going Big Block!

Sid Coleman
Sep 18th, 01, 10:45 PM
Gotta jump in here with the other guys-cam selection must be made as part of the overall plan. Compression, gears, stall, heads all combine to determine your cam selection.

As an example, I used a crane 300H in my 89 350, actual figures worked out to about 214' at .05, 450 lift. This cam, with a stock head, has a slight rumpty idle, but the car doesn't begin to pull until about 2500, and then runs out of steam around 4800 due to the heads and my 600 carb. I did not pick a good cam for that combo. NOW-if I can get a set of vortec heads on it, that may even it up. Large duration cams NEED that compression to make low end power, and heavy chevelles NEED low end power!!!!

Listen to the other guys and plan accordingly-you'll be much happier.
Besides, bottom end torque is what helps those smoky burnouts!!! http://www.chevelles.com/forum/biggrin.gif

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71 Ragtop, finally under reconstruction!
MCC #347, TC (Gold) #174
N3JHV@bellatlantic.net

iwantachevelle
Sep 19th, 01, 8:44 AM
Thanks for the advice. i understand what you say about bigger not always being better. the engine id going in a figure 8 car. iam kind of imbarassed posting here because you guys are used to talking about things that are actualy nice. but it is the cheapest form of racing i can think of and i am 17 so... any ways i know the rpm will not drop a whole lot during the race. so i have a couple of options. i can get some redone 305 heds for more compression but the small valves will hurt horse power. i am going to but an edelbrock rpm manifold. i already have the holley, and headers, so i would like to know what is the best route for the most all around power. What heads (mine are 1.94), what lifters , cam, and anything else you guys can think of. thanks, i really appreciate your time and advice. p.s. I stripped the engine down to the short block yesterday before sun rise http://www.chevelles.com/forum/biggrin.gif this is mostly a learning expirenece.

?
Sep 19th, 01, 9:07 AM
I'm only 17 too, 2 years ago I was in the same spot as you. Just don't get carried away with rear end gears... you'll live to regret it. http://www.chevelles.com/forum/wink.gif

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kenny

85 El Camino 355ci
350 turbo - 4.11's
best run so far 12.92
My Page (http://kenny350ci.hypermart.net)

Gene Chas
Sep 19th, 01, 9:15 AM
Kenny, that awful noise of solid lifters???

Dude, you;re tweaked. ITS BEAUTIFUL! http://www.chevelles.com/forum/wink.gif

No solid cam out there can hang with 8.5:1. Not much can. Its not enough compression to run any duration whatsoever. The biggest cam I would consider for this is #1 on this list.

http://www.cranecams.com/master/apps/chevy16.htm

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Member #62 Gold/ACES 03112
67 SS396(427-3X2) (http://www.chevelles.com/feature/october2000.html)
Be Big, Be a Builder

?
Sep 19th, 01, 12:57 PM
Gene, you're tweaked ITS NASTY! http://www.chevelles.com/forum/wink.gif

Good thing about it - when people think your motor is knocking... that always cracks me up. Then I get to explain to them why it clicks.

iwantachevelle: I was going to say the same thing about your compression... you might just want to start saving, and reading. This way you can save up, have a fresh drivetrain and know what's going to suit your needs. Does the motor run fine now? If so I wouldn't touch it... I under stand the thing about wanting to have a car that will SCREAM... but run it until it dies. Then pull it, and do all the work you want.

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kenny

85 El Camino 355ci
350 turbo - 4.11's
best run so far 12.92
My Page (http://kenny350ci.hypermart.net)

Gene Chas
Sep 19th, 01, 1:50 PM
Hey Kenny, I resemble that remark! http://www.chevelles.com/forum/wink.gif

Good advice. Not much can be done with an 8.5:1 motor.

ratlover
Sep 19th, 01, 2:33 PM
beings you are going to derby this car I would agree just to run it till it pukes. But beings you already tore it apart(did you lable the lifters and pushrods so you could put them in the same place?) Might wana check with the track to see what is legal(like the aftermarket intake) If you got it all tore apart might as well do a cheap rebuild with new bearings and rings and such and call crane and tell em what you got and what you wana do. Things like a performer rpmcan go on your next motor when you puke this one and headers too. Not much can be done about your compression unless you get some new pistons??? Please though...spend money on saftey I see guys in the bomber class with some really scary rollcages(makeshure the the seat wont fold under the rear bar) Get a good helmut and have eye protection(tear offs help tons on a heavy track) And a decent suit with gloves. Dont just do the required. This is probably comon sense and such but I have seen some really scary vehicles out there. Be safe

Edit: 194s will do you fine at this point, depending on what casting they are you might wana step up to an aftermarket if they aint worth geting ported. The proactions are some pretty cheap iron head and so are the worlds. Leave it nasty and greasy and keep the competition guessing http://www.chevelles.com/forum/wink.gif

Philip

[This message has been edited by ratlover (edited 09-19-2001).]

fmj355
Sep 19th, 01, 3:59 PM
My experience with low buck stock cars is that most guys have way more power than they can put to the ground. If you have lots of power, it all goes up in tiresmoke. Safetyfirst, handling second, power third is the way to survive and do well early. If you find the right guys to help, handling is cheaper anyway.

?
Sep 19th, 01, 4:17 PM
<BLOCKQUOTE>quote:</font><HR>Originally posted by Gene Chas:
Hey Kenny, I resemble that remark! http://www.chevelles.com/forum/wink.gif

Good advice. Not much can be done with an 8.5:1 motor. <HR></BLOCKQUOTE>

That is, unless he wants to pull off some kinda cool customized twin turbo Chevelle. I'm sure you could find junkyard parts to do that as long as you have someone who knows what they're doing and can weld. http://www.chevelles.com/forum/wink.gif I know… I know… I’m nuts. http://www.chevelles.com/forum/biggrin.gif

As fmj355 said suspension is also a good idea, you'll like being able to hook instead of roasting tires (especially when money is an issue).

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kenny

85 El Camino 355ci
350 turbo - 4.11's
best run so far 12.92
My Page (http://kenny350ci.hypermart.net)

[This message has been edited by ? (edited 09-19-2001).]