Thread: How about this cam in a 283?

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I bought this cam a couple of years ago to put in a Caprice but had an offer on the car that I couldn't refuse and sold it before I put the cam in it.
I am now building an S10 with a 283 and was wanting suggestions/opinions/boo's/hisses/ anything about how good it might be in the 283. Cam spec's; lift 465 in./488 ex.Duration @ .050 224/234; advertised duration 282/292; Timing @ .050 Intake opens 3 deg.btdc,closes 41 deg.abdc; Exhaust opens 56 deg. bbdc,closes (2) deg.btdc; 114 LSA.
Motor has .030 flat top pistons,305HO (416) heads with 9:1 static compression.
Offy 360 intake with holley 650. Th350 trans with 411 gears
Would this be a good/bad/ugly cam for this build? I can't make up my mind on cam selection so I am open to other suggestions Thanks.

The s-10 is light ,it should be ok.The intake seems to close early for a cam with those specs.Better check the static and dynamic compression to be sure its compatible.

WAY TOO BIG for that compression ratio. I wouldn't run anything more than 265 degrees at .005" lift duration in that motor.

You have to keep in mind that cubic inches "tame" a cam. A 283 will run much rougher with the same cam as, say, a 350. An S10 is light enough to put up with more cam than a full-size truck. Depends on you in the end, and how you want to drive it. I ran much the same cam in a 283 in a '54 Chevy and loved it, but it was a bit much around town. Great on the open road, where I do most driving.

R Pope I agree that this cam would make the 283 'rough'.Seems to me that this cam would suit a street 400 motor alot better to produce the torque it was designed for. But I can't understand why some think that the cam may be too much for the smaller bore but higher reving 283??? If the 283 has good high rpm potential with low speed sacrificed somewhat,,,wouldn't a cam like this thats designed to produce good low RPM power give the 283 good power where it needs it most,at lower RPM's without hurting high RPM power?

With zero deck, I figure the static compression ratio at 9.18 and the dynamic compression ratio at 7.75:1, a little light. The motor will run with this cam, but will be a little soggy. A shorter cam will work better for a street motor on pump gas.

whats the bore!?

0.030" over 283, I figured it at 3.905".....

Yes,I am staying with the .030 which is 3.905" bore. And the pistons are .030 in the hole. I was going to use .015" head gaskets that the factory used on these heads. About .045 quench with flat tops with valve notches. The heads have 58cc chambers. My original plan was to build it as a brackett truck and build it for top end/high RPM only but changed my mind.It will be a street (weekend/occasional driver). So now I probably should back off using this cam,(by the way the cam is a Summitt 'house' cam #1105).
I've never built a motor as small as a 283 for a street vehicle so I've no idea what the 'max' may be as far as duration figures???

You guys have to understand.....THE INTAKE CLOSING POINT ON THE CAM MUST BE MATCHED WITH THE STATIC COMPRESSION RATIO. You could have a cam in a 283 that was less than 200 degrees @ 0.050" tappet lift and it would run great if the ICP and SCR were matched. On the other hand, you could have a cam in a 283 that was 270 degrees @0.050" tappet lift and it would also run great if the ICP and SCR were matched. Your motor, with a SCR of 9.1:1 will only match up with a cam something like this, with a duration of 204/216 and a closing point of 29 degrees after bottom dead center. This cam in your motor will make a DCR of 8.223:1 and would run REAL, REAL good on pump gas with your 0.045" squish. It's ground on 112 degree LDA for good manifold vacuum and will rev to 5,600 with the proper matching springs.
http://www.cranecams.com/?show=brows...tType=camshaft

P.S. In order to achieve the same DCR of 8.2 using the cam you have on hand, you would need a static compression ratio of 9.8:1

Thanks TECHINSPECTOR1. I thought Isky was your favorite? Well I've put too big of a cam in motors in the past and know the effects but that 'camitis' bug gets me and I lose all reasoning. But not this time. I'll try that Crane cam or something very similiar so as to keep the static compression up. Keeping the scr up should benefit the entire rpm range I do believe.

Use any cam you want, just be sure the intake closes at around 29 degrees after bottom dead center (28-30).

should rev to farther then 5600 even if it is a hydro cam.

Scooter, with the springs recommended for this cam by Crane, the valves will float at 5,600. This is not a high rpm cam because his static compression ratio will not support a high rpm cam. If you want to rev the motor higher with this cam, you can install stiffer springs but the increased pressure over the nose of the lobe would probably wipe the cam out pretty quickly. Not only that, but you're out of cam in this case by 5,000. It's all about the combination Scooter. If you want more cam and more rpm's, increase the static compression ratio.

OK,I understand the reasoning so far. But lets say I am stuck with this block and pistons and want more horsepower than this setup would produce but yet keep it a streetable vehicle.What would you do? And I do believe that the biggest valve I can use is 1.94". Gears,converter,special grind cam,,,? I am trying to learn and I believe that this motor/vehicle could be a screamer if built right,,,considering the limitations of bore size and compression. Maybe I should ask it like this,,,does the late ICP really reduce compression pressure so much that the motor won't make horsepower with the bigger cam? If it creates such reversion back into the intake then is the 'only' answer a blower for such a motor? I seriously understand about half of what this means but I am trying to learn why 'bigger isn't better' when the motor is just a pump???