Stock heads..

[ukregal]

I have stock 1.72 heads 😢

I have looked into shipping some heads over but the cost of shipping to the uk is very high (looking at close to $1400 for vortecs back here).

So....is there anything I can do to pep these heads up?

Any advice would be great 😀

 

[KrisW]

For a 305?

I believe they can be opened up and have 1.94" valves and seats installed without hurting anything. Buying those little pieces and shipping them shouldn't be too bad...

 

[beeterolds]

the largest valves ive seen in there was 1.84s. if these are going back on a 305 it will be more than enough....if it were going on a 350 it would make a badass street cruiser....but id do some porting to enhance flow... we have a set of big valve 305 heads on my friends car and it runs pretty well

14.40s in the quarter mile

 

[79malibu]

heads

a while back when i was talking to a machinist i was told that in a 305 bore you can't fit a 1.94 intake valve and make it clear. he did say that to open the exhaust up to 1.6 from the 1.5 with porting would make a great difference in aiding flow.

 

[KrisW]

He's wrong; I've seen guys running 2.02 valves on 305's as well.

People think they won't clear because on some crappy 70's 305 heads you will hit the water jacket if you try the 1.94's. If you have the 80's heads you're usually okay.

 

[ukregal]

Thanks for the replies and advice. Yep its going on a 305 and I think they are the early heads the numbers are 376450 which mortec says are 75-81. The guy I bought them off is someone I can trust 100% and he said they are off a 83 Camaro so I think it must have had a engine swap at some time.

 

[85 Cutlass Brougham]

I would not run 2.02 valves on a 305 even if they do not hit anything. The reason is that the small bore diameter will shroud the edges of the valves and disrupt the flow out of the heads. Even the World Products S/R torquer 305 heads only use a 1.94 valve size. I know from experience on another engine that you can have too much of a good thing with regards to valve size. Trust me, use 1.94 valves with 1.5 exhausts and tune for low to mid RPM torque and not horsepower. It will be a much better experience to drive that 305 configured that way. I would go with a Comp Cams Xtreme Energy grind for the cam, probably the next one lower from the XE 262. You could use the XE262, but idle quality would not be smooth like it would be with a smaller cam. You can also run the Quadrajet your engine may have come with so long as you build it properly and it has no computer provisions.

 

[ukregal]

I have a performer inlet, 600 Holley, comp cam 268HE, Headers, dual exhaust with flowmasters.