305 No power.

[Rule_So_Hard]

I am about as tactless as they come! No personal insult intended.

right on

 

[rich weyand]

Oh **** you may be right about them being 72cc. However the valves are not to small compared to some 350 heads specifically 991 heads which everyone knows is the best truck 350 head.

991 heads =1.72, 1.50 valves @ 76cc

305 heads 0810,2188 86'-91' = 1.84, 1.50 valves @ 72cc
305 heads 2601 80'-86' = 1.84, 1.50 valves @72 cc

so yes the 305 heads have potential when compared to the 991 heads especially when you figure in a valve and port job and higher compression and if you wanted to lower compression you could unshroud the valves.

Compression won't be much higher with a 4cc difference. Maybe half a point, probably not that much. The smaller intake valve (compared to 882 heads) will reduce high end hp a little bit as they won't fill as well at rpm, but down low it won't make any difference. Still gonna be over 400 lbft with those cams I mentioned above. Give up maybe 10 hp on the top compared to 882s.

 

[Tricky991]

I took the valve cover off and these are the 2 numbers I found,

14022601
&
B155

 

[firebane]

I took the valve cover off and these are the 2 numbers I found,

14022601
&
B155

14022601...80-86...267/305......1.72"/1.5" or 1.84"/1.5" valves, 53cc chambers

 

[MadOgre]

Yes, 80-86 305 2601 heads 1.84 and 1.50 valves 72cc chambers. If you had those heads worked to accommodate the largest valve possible(if I remember its 1.88 or 1.90) And mildly ported they would work well. It might be more cost effective though to find a good used set of 991 or 993 heads. You would have to check and see which is cheaper.

 

[MadOgre]

If they do have smaller chambers like firebane posted you can have the valves unshrouded which will increase the chamber size

 

[Tricky991]

Alright, I think I will look for some heads for it. Which heads are better in your opinion?

 

[MadOgre]

well the 991 heads are supposed to be the best all around head for truck engines because they usually don't go past 4500 rpm when being used. The 993 heads are good too and have larger valves for more upper RPM power then the 991

 

[Tricky991]

I am more concerned about low to mid rpm power. Which would be good for that the 991s?

 

[MadOgre]

Yes the 991s are the ideal head for a truck application. I have a set I am putting on my next engine with a 3970010 block

 

[Tricky991]

Alright, 991 heads it will be then

 

[firebane]

Honestly unless you are intending to put a bunch of work in like exhaust, cam etc any head will really suffice.

 

[Tricky991]

Well I am thinking about using either 12-235-2, or 12-300-4 from comp cams.

12-300-4 looks better for the 991 heads.

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=70&sb=2

 

[firebane]

Well I am thinking about using either 12-235-2, or 12-300-4 from comp cams.

12-300-4 looks better for the 991 heads.

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=70&sb=2

New cam will require new lifters and don't forget about headgaskets too.

 

[Tricky991]

Mmhmm will do both, also rings, bearings etc.