cam question

[84chevysilverado]

Howdy just want some opinions here. Im lookin at installing a new cam in my 305 do u think that the stock valve train can take a comp cam thumper cam with adv/dur 279/297, intake/exhaust .479/.465? I have to do this for school and id like to  practice before i try install a cam into my 383. I am aprenticing for an auto mechanic and have installed cams before but just stock replacements. thanks marc

[Layne]

I hear you shouldn't go past .500 max lift and you need a .30 give or take? Correct me if I'm wrong, guys. Is the motor bone stock? Auto/Stick? Rear gears? Any cam can work, but the right cam will be better.

[Josh454]

Yeah I wouldn't go over about .420 lift on a bone stock 305.

[84chevysilverado]

alrighty its a bone stock 305 with a 700R4 tranny. Any one have good cam ideas? I really like the rough idle cams. like i said before this is for school and for fun pretty much thanks marc.

[ccz145a]

Unless you up your compression it will be a dog with any cam with a rough idle.

[SUX2BU99]

Since it sounds like you are basically looking for something with just a tough sound and don't care too much about performance or driveability then maybe a Thumper is for you. I would change the valve springs though to something that would accept at least the lift that the cam will produce. Highly probable the stock springs won't take much more than what an "RV" type cam would dish out and those don't usually have rough idles.

[84chevysilverado]

thats exactly what im going for cause its only a 305 so im not really going for loads of power more for sound. so get springs to? what about push rods? i wont be able to reuse my stock ones right

[07montecarlo]

get some tried and true "z28" springs and youll be good with that lift.. pushrods will be fine.. what are your goals? and stock compression is going to make a huge issue with power and gas mileage, but i guess if you want sound,  thumpr cams sound the way they do because of the lsa, (lobe seperation) is like 107..

[84chevysilverado]

well Iv done some research and im not going for the thumper cam. I did buy a lunati 268 bare bones cam this is alot more on the conservitive side of things with a noticible idle and works with stock torque converter and stock gearing. so il reuse me push rods and rockers. and my stock springs should work right because its not over .480 max valve lift? here are th specs on the cam.

260  268  ADV   

214  224  @.050" 

.443 .465  Valve lift @1.5:1   

112/107°  Lobe sep. angle

 my goal is for an engine with a bit of a meaner sound and a bit of performance thrown in. but il only be driving the 305 untill my 383 is done. thanks marc

[07montecarlo]

comp cams magnum 280h.. you may be lacking a bit on the cr though

[VileZambonie]

I hear you shouldn't go past .500 max lift and you need a .30 give or take? Correct me if I'm wrong, guys.

I don't know what you are trying to say. 


If you're just doing this as a cheap temporary project throw it in there. It'll sound a little better and will be a good learning experience.

[Layne]

.500 in max valve lift with a .030 cushion factor for valve wear and tear and irregularities.

[84chevysilverado]

thanks Vile u got it in a nutshell. but no one really answered my question about the stock valve springs an push rods. will they still work with this cam?

[CR10]

To be honest with you, If you are looking for a cam upgrade, it´s always a good idea to replace lifters, springs and pushrods, and since you are there change the valve seals, it´s always a good idea to be on the safe side...

[screamin86]

I always like the summit 1103 cam its the same specs as the last cam you listed but only $70 with lifters. Ive got the 1103 in my 305 in my 82 ta and the eglin version of it im my 350 in my k10.