Another 305 head queastion on a 350

[87montecarlomrc]

Ok the heads are the basic 14022601, and the motor is the l98 (I forgot the number) buts the 245hp tpi motor with the 4 valve relief pistons. But it's carbed... Everything is stock on the motor and the 305 heads are stock to, I'm wanting to port them to help flow. Should I put this heads on or not. Will it be smarter to just port the l98 heads and keep them, the motor runs real good but if Should I swap heads since I already have both I was just wondering what everyone thought

 

[87oldssalon302sbc]

The 601 casting would support a mild 350 with no problem, it will bump up the compression also. A little bit of pocket porting and cleaning up intake and exhaust ports will help flow, the L98 head would be a good head too as its made for the 350 cid engine.The 601 has 53cc combustion chambers and the L98 has 58cc, as long as you're not planning on turning it 8000 rpm and getting 500 hp out of it which ever head you choose will work fine. As I've ran them both on 350 cid with good results.

 

[larryo454]

X2 on the 305 head your not buzz it to 8000rpms,And whats the #1 power builder????? compression and #2 is flow.

 

[87montecarlomrc]

It won't see any 8k hahah, it might see 5500rpm but that's just barley and not very often I don't drive it hard most the time, I wasn't forsure what all the cc was on either head but I didn't know they was so close lile that. I think a stock l98 has like 9:1 compression and with the 601 heads it will raise it up some but not much where I have to run like racing gas will it? I normally run the highest I can get anyways at the pumps

 

[larryo454]

No you are not going to need race fuel for 9.1,I have a 12.5 bbc that i run on 92octane because it has alot todo with the cam i am running and the duration @.050 is 268 on intake and ext. More overlap the more the cylinder bleeds off this is why you need run a much higher compression engine with a much bigger cam.If you look at some comp cams the foot notes say you need 11.1compression and 4.10 gear this is to help with the bleed off of the cylinder.You take the compcams cam 305h put that in you 8.1 or 8.5 compression engine with a stock converter that stalls at 1300rpm and from a stand still mat the peddle i bet the engine shuts off to much load at a stand still with no power under 1500rpms i did it about 10years ago lol it is all in a combo.

 

[87oldssalon302sbc]

Lets back up a minute, which heads do you have on it now, are they iron or aluminum? The true L98 came with aluminum, which were 58cc, but if you have the iron head, try too get the casting number. You will have to look under the valve cover, if they are iron, the combustion chambers could be 64cc or as big as 76cc, it depends on the casting numbers.

 

[87montecarlomrc]

My l98 heads I have now on the motor are the 183 iron heads

 

[87oldssalon302sbc]

Ok, probably 193, which is a tbi 350 head, if you look in the intake ports they have all sorts of restrictors cast into them. GM was trying to make the air coming in go in circles, but it killed the flow, if you choose the 601 you will be bettering yourself all the way around. Even with the smaller intake valves the 601 will out flow the 193 tbi heads, and you will have more compression. If you stay with the carb. and 270-286 advertised duration cam you'll have a nice little street combo and it'll have a good lopey sound.

 

[87montecarlomrc]

Ok cool thanks man. I've learned about the RBI heads some and found out about the hump thing in there for torque but it has terrible flow, my cam I have now is a roller [email protected]" 207'/213' Lift (w/1.5) .415"/.430" LobSep 117'
, does that sound good for them heads.

 

[87oldssalon302sbc]

That cam will give you tons of cyclinder pressure, which don't get me wrong its not a bad thing. It may just be real picky with starters, if its a true flat top engine, and you'll see that when you pull the heads. You will have a lot of compression all of the time, excellent throttle response, even with stock converter, but it will idle smooth @ probably as low as 600rpm. I would say you would have a very good street engine, even if it has dish pistons with the 601 heads you will have around 9:1 or 9.5:1 compression, either way 93 octane and a little ignition timing adjustment, you'll be on your way. LOTS OF LOW END TORQUE!!!!