cam choice time...your opinions

[z ya]

OK its time to pick the cam and i think I have it narrowed down to a few.The motor specs are 355 sbc/ported and polished 291

63cc heads 1.94/1.5's/air gap intake/3310

holley 750/10.4 comp ratio.I am going with

comp cams.Heres the choices: 280/480,286/490

or dual pattern 274/286 with 487/490 exhaust.

The tranny is a th350 with 2300 stall.All

the cams are 110 lobe sep.Its going in an

70 240.The comp guy said go with the 274 for

all around perf.Its rpm band is 1800 to 6000.

OK lets here it....

[Racin_Jason]

Well I'll tell ya I wouldn't go OVER the 274 if you want to run it to only 6000rpm. With those camel humps and the compression I might try something in the 280's but its gonna go to 7000 easy. The 268 would like that 2300 stall ALOT..anything higher is gonna be alittle mushier off the line but be alot peakier later on..but with such a light car the 268 at that compression would over power street tires REAL easy off a 2300 stall. Clear as mud?..if it were my car Id run it this was..street car? = 268 with a 3.23 or 3.54 rear would be a grunty little SOB that would haul up to 6000+////RACEcar? Id run something in the 280s..maybe even low 290s and swap to a single plane mani and 3.70s out back. The car will leave alittle softer but the 4000-7500 would be BRUTAL with your combo. My $0.02...

 

I just noticed the humps are only 1.94's...my opinion still stands but the RACE setup would be a 'bit' less than BRUTAL..but not much

 

[This message has been edited by Racin_Jason (edited March 09, 2001).]

[DavyZ]

I personally like Jason's recommendation of the 274 for the street. I guess it depends on how much you drive this car and what kind of driving you'll be doing. I would say to go with the milder cam because, dude, you have no idea just how fast that sucker will be as you boil the baloneys all the way down the street. Don't make the mistake of over-camming the car. After much research, I decided on a 274 cam for my V8, because the car will be very quick, very responsive, and still manageable with respect to highway driving. That same cam in you car will produce about 375-425hp(?) I guess you must ask yourself, "how much power do I really need to have fun/be fast/hurt myself? You are already there with the "mild" cam. If you don't like it, stab in another cam; they are not all that expensive. Hope this info helps. Choose wisely.

 

David

[Guest Anonymous]

I would defiantly go with the dual pattern cam. Your heads need help on the exhaust side and that is what that cam is designed to do.

[pparaska]

...double hump heads. The generally don't flow much more if you open the valves beyond 0.46-0.48. And the exhaust ports don't flow as well as the newer heads, so that dual pattern cam makes alot of sense. I'd go with the 274/286 for a street ride.

 

------------------

Pete Paraska - 73 540Z - Marathon Z Project

pparaska@home.com

Pete's V8 Datsun 240Z Pages

[z ya]

OK , I know the 274 is sweet all around,but

I plan on going to some trick flow 23 degree

aluminun heads when possible.Also, if I

later go to an 700r4 I figured that it would

almost have TOO much bottom end and never

hook up.My brain says 274 but my heart says

286...

[Guest Anonymous]

Chevy style 23 deg. heads have a much lower exhaust to intake flow ratio than would be desirable. The dual pattern will serve you better. The exhaust side of the 274 cam is the 286/490. If you worried about the bottom end lower your stall speed. Light car, lots 'o tork, independent rear?, I doubt you'll need much. Plus if you do the 700R4 it has a 3.06 first gear, and you'll have real problems hooking that first gear. Especially if you stall the motor into it's tork band. It doesn't take much to move a 2600 lb car. I personally am thinking 276 roller dual pattern cam, single plane manifold, stock stall converter, 23 Deg TFS heads, and 200R4. Gearing plays a large roll in what your trying to do.