I'm looking for a stock replacement cam for my 305. From what I've been reading in other posts, acceptable lift on the stock springs ranges from .440-.480, although the .480 seems...high.

Came up with a Comp Cams 246PE (12-305-2). http://www.compcams.com/Cam_Specs/Ca...x?csid=69&sb=2

The website doesnt state a need to replace springs, so I'm probably good right?

Anyone think I can go a little bigger?

The car's getting headers and a dual exhaust as well.

Thanks - Ryan

 

If you're wanting to run as much cam as possible, I'd suggest a 212/218-112 .447/.454 will be a realistic maximum.
Springs are a wear item. It's not wear you can see, but they lose tension. You can get a good set of new springs for $26 from www.competitionproducts.com, part number 98111, IIRC.
This is also the time to replace valve seals.

 

Well, thing is... I've already had the heads cleaned and I put the old springs back on. Yeah, I did replace all the valve seals and tiny o-rings when I did this.

I wouldn't say I'm trying to max out the cam, just put something fresh in.

Would it be wise to replace the springs anyway? If so, maybe I will go with those specs. you mentioned. And for $26 it seems worth it to replace them anyway.

It's the removal and installation with my crappy Auto-zone spring compressor that's gonna' get me... hehe.


-Ryan

 

I'm not saying that cam is the best match for the rest of your combo, but you asked how big you could safely go, not what would be a great match. Saying your trans and axle are stock tells us nothing. Is it a 5 speed manual, a 4 speed automatic, or has something else been swapped in? What's your axle ratio? Are you running EFI, or a computer controlled carb, or an old style carb? Are your pistons dished or true flat top?
The cam swap can be worth the hassle if the cam is well matched to the rest of the car. The cam you picked isn't a great match for very many realistic 305 combos, and the one I listed might be all wrong for your pistons and gearing.
Whatever you're building isn't top secret. If you feel otherwise, shoot me a PM.

 

from what I understand the LT1 cam is about the max for stock springs and its pushing the limits of the springs

 

Like the cam I listed, the LT1 cam is around .450" lift. But the OP has an '85, so if the block is an '85, or any pre-'87, then the LT1 cam isn't even an option.

 

Thats right sorry forgot he was not on a roller cam set up

 

That cam would probably work OK with stock springs. So would the Summit house brand K1102 (Don't worry- it's a quality cam kit. I have the bigger K1103 in my Malibu's 383).

 

Stock 305s shouldn't use cams with 10 degrees extra exhaust duration, unless you occasionally use a little nitrous or mild boost. 6 degrees isn't really good. I've flowed enough 305 heads to know it's okay to use a single pattern cam with any of them that haven't been cut for 1.94" intake valves.
And again, it's a mistake to try to pick a cam without knowing the important info about the application.

 

The car is a 4spd automatic, the 700R4. I'm not sure about the gearing but it may be 2.72(?) The carb is CC. And the pistons are flat top, but they have those 4 dips in the center of the piston (don't know if that means anything). I'd look at the head casting #, if that would give any more helpful info., but I don't have them with me right now.
Yeah, I should re-phrase my question to what would work best with the engine and the stock components.
Does any of the info. I put up their help with another cam suggestion?

Or would you still recommend that cam you mentioned, Atilla?

Appreciate the help, all of you.

-Ryan

 

You will be relatively happy with a COMP CAMS 12-205-2 for the other stuff you've listed. Those dips in your pistons are valve reliefs, not that you need them for this build. This cam will be fine with the springs you have, but COMP requires you to use their springs if you want their warranty. If you want that, the best COMP springs for you to start with are their part number 980-16.
Also, this cam is emissions legal, and will give better low-rpm torque than either of the other cams earlier.

 

Awesome! Cam looks good. I'll still leave it open if anyone else has any suggestions, but that 205 looks good to me! I'll also take those springs into consideration as well.

Thanks for the help. Much appreciated. Probably order in the next day or so. ^_^

-Ryan

 

wouldnt go any bigger than a comp 12/206/2 with a set of srings if your gonna be a daily driver an wanna play.if you dont want to burn gas go with the 205. Any thing bigger thang the 206 you will need to add a converter (stall)