1983Fbody

I have a pre '86 style 350 with retrofit hydraulic roller lifters and 1.5 rockers, rpm air gap and a 750 edelbrock. Right now I have a circle track camshaft in the car and I don't like it, it seems to have too much duration or something. I don't know anything about it other than it has double valvesprings and very little lowend(lots of midrange) with a big lopey idle. The cam worked well with my five speed because it was always cruising at about 2500rpm. I do most of my cruising at 1300-1600rpm now (sixspeed 3.42 rear). I want a cam that is matched to my intake and I'm willing to sacrifice some of the upper rpm power for more lowend. I want something that will work good with my 350 now, and in the future I would like to upgrade to a 400 (reusing the same intake,cam, etc. off the 350).

I'm looking at a couple of different cams from lunati, and comp cams with advertised power range of 1500-5500, and 1600-6000. The lifts are both near .500 is this too much for a "driver" or could I run more?

http://www.lunaticams.com/Camshafts/...tSSHydRol.html

Second cam down from the top ?

I don't want to plop down close to 500.00 for the cam/springs/retainers/etc. and be dissapointed. Thanks in advance,
Ben

RB83L69

That's a good cam, but for a smaller motor. It's really not much cam at all; I have more of one than that in the 305 in my daily driver, that passed California emissions (they didn't notice it was there, so they didn't ask for the CARB EO #!!!) so I think you can probably use a bit more than that one.

http://www.compcams.com/Technical/Ca...ML/128-169.asp look at the XR270HR and XR276HR, on page 138. I ran the XR282HR in a 400 for a while, it got about 16 mpg on the highway like that with a Holley 800 double-pumper. That would probably be too much for normal street use in a 350 though.

You probably don't need new springs or any of that, just a cam and some gaskets.

1983Fbody

I like the looks of the xr270hr, does anyone have experience with this cam?

Also it says when using a "six valve style" mechanical fuel pump to use a brass tip pushrod. I have a holley mech. fuel pump, not sure if it's the six valve style or not. I read that some roller cams are made of a different material and the stock fuel pump rod can wear out. Should I get the brass tipped rod just to be on the safe side?

94-6spd

Here are some camshafts that you might call TPIS about. I put the zzx camshaft in my 406 and love it. I don't know what heads you are running but these cams are worth checking in to. I have found that TPIS cams have a very flat torque curve.

ZZ-9 HydraulicRoller:

Intake Exhaust Advertised duration 282 287
Duration at .050 212 226
Gross lift .483 .520
Lobe separation 112

ZZ-409 Hyd Roller:

Adv. duration 287/287, duration @.050 226/226, Lift .520/.520. 112 LSA.

ZZ-9X Hyd Roller:

duration @.050 225/240, Lift .525/.558 on a 112 LSA.

ZZ-X Hyd Roller:

Adv duration 290/290, duration @.050 239/239, Lift .558/.558, on a 112LSA.

Streetiron85

[QUOTE]Originally posted by 94-6spd
[B]Here are some camshafts that you might call TPIS about. I put the zzx camshaft in my 406 and love it.

ZZ-9 HydraulicRoller:

Intake Exhaust Advertised duration 282 287
Duration at .050 212 226
Gross lift .483 .520
Lobe separation 112

I've looked at some of the charts in the TPIS publications, and it seems like if what they are claiming is actually true, they do have a REALLY flat torque curve.
Do you have any personal experience with the ZZ-9, on a 350 or a 383, with an LT1 intake?

Thanks

1983Fbody

I have a set of late 70's 305 heads I will port and plan to bolt them on when I do the cam swap. I know the 305 heads suck, I think they should flow as well as the junk i'm running now (mid 80's tbi heads) and cheaper just to throw these rebuilt heads on than to have the tbi heads rebuilt.

I could spend the cam money on some better cylinder heads and I'm sure the low-end-lack-of-power-problem would improve, then I would still be stuck with a cam that I know nothing about and since I don't rev past 3500 more than a couple times a week, why would I want a cam that doesnt start making good power until 2000rpm? I don't know what to do, the springs I have now should handle at least .500 lift so I would like to stay close to those numbers.

If I get a cam measuring tool like I've seen in summit racing, will that tell me the lift and duration of the cam I have now?

Streetiron85

It isn't really that nessecary to know what the numbers are for your cam that you have right now. It isn't a street cam, from what you're saying. And that means that almost any one of about 50 choices out there would make you happier.
So if you have retrofit hyd rollers, you don't need to buy anything much, other than a camshaft. And that will be a lot less than $500.
New take offs can be found for $80 or a new aftermarket one can be $300, and everything in between.
Anything would be an improvement. figure out your CR and how you want to drive the car. Do you want to race?
There are some popular cams that are used by the guys here. do some searching and you'll probably learn a lot.

jimmy_mac

In my 350 now with vortec heads. If I did it over again I'd go one step up, but I do like the cam. Pulls real hard from 2000-5500 rpm. Probably would pull to 6000 but I don't like to do that a whole lot. Idles nicely. With non ported 305 heads I had on previously and a single 2.5 inch exhaust pipe I trapped at 98mph in the 1/4. Gets about 18-20 mpg.