Help with cam choice
 

What i have.

84 Z28 with the LG4.
Stock 3.23s
Weiand Intake
Hooker shortie headers.

What i plan to get before or soon after the cam swap
L69 Computer
build the rear with 3.73 posi.
Port and polish the heads

My use.
i plan to build a new engine (355) but i want something fun to play with while i have the 305, heck if i get another car with a v6 just swap that in.

with the 305 i'll be driving as close to a DD as possible.
i'll probably be getting on it quite often.



ok so i was looking at a bunch of cams and heres one i'm particularly interested in/wondering if it would be alright. in addition if theres anything that i would need to do.

http://www.compcams.com/Cam_Specs/Ca...x?csid=78&sb=2

any thoughts? suggestions? criticism? bad jokes?

Re: Help with cam choice
 

bump

Re: Help with cam choice
 

It should be a fun cam. Not too radical and not too tame. It depends on how many miles you're going to put on it as a daily driver since the gas mileage will be traded for power.
You'll need lifters and springs and maybe rockers (depending on the heads).
I wouldn't spend a lot of time porting the heads as these have the 1.84" intake valves and it's not going to make much difference. Get the heads milled instead ($20ea) to bump the C/R from 8.6 found in the '84 to the 9.5 found in the '85 LG4. The cam swap will lower the dynamic compression ratio more than enough.
Does it have to pass emissions testing?

Re: Help with cam choice
 

well as for driving everyday if the legacy continues, it will run for about a month, something else will break, then it will sit for 1-2 months.

as for emission tests, ehh.

i got it inspected in august. all the smog stuff was gone and it still passed.
and i dont think the place i took it to did it just for the sake of passing.

Re: Help with cam choice
 

i just cameacross this cam

http://www.lunatipower.com/Product.aspx?id=2505&gid=309

what do you guys think?
between this and the other one i posted which would be worth getting?
and for either do i need any sort of machine work done?

Re: Help with cam choice
 

It's a little tamer split profile cam with a little less duration on the intake side. Probably have better vacuum at idle. Not real sure what the ECM will think of either one. But with both, I would check the retainer to valve guide clearance (actually the valve stem seal). How much lift you can get away with, depends on the heads. This varies between heads of the same part number to heads of different part numbers. There was a post a while back showing the top of a head littered with lots of tiny smashed valve stem seal garter springs from a cam change and inadequate clearance. Most stock heads can handle .460" lift (but not all, it just depends). You can check this before you order the cam. You'll need a dial indicator with magnetic base in addition to the tools needed to change valve stem seals.
You should be fine with valve-to-piston clearance.
I'm not 100% sure about the rocker slot. This depends on the stock rockers in the engine... probably would be ok. It's possible to check this too when doing the above, using the "light spring" technique.

Re: Help with cam choice
 

oh ok thanks, this may end up waiting till feb, right now i'm working on the exhaust
where could i read up on how to check the valve stem steal?

Re: Help with cam choice
 

Read in this article section about checking retainer-to-guide clearance.
Use the light spring and dial indicator like in the V/P clearance test to measure travel.
(Can you tell I'm an Isky guy?)

Re: Help with cam choice
 

i just put a magnum 270 in my 305. on a budget, we're still waiting on springs(not smart i know, but i'm broke) but it runs pretty good. actually pulls better down low that the stock cam did, and has more power above 3000rpm. i'd say do it.

Re: Help with cam choice
 

did you have to do any other work?

Re: Help with cam choice
 

no. i already had the cam and headers laying around, and when i popped a head gasket i firgured if i was already there. only other thing i did was change the timing set. stock stall still in place.

Re: Help with cam choice
 

sweet, any sound/video clips of the cam?

Re: Help with cam choice
 

i don't have a camera, so no sound clips.