does any one have a offy or a clifford 4 barrel intake manifold and possidley a carb they would like to sell.and does any one know if the intake and headers make a huge difference,i just ordered a set ok hedman headers are they any good.

 

You could try looking on ebay. They have some on there from time to time. I have a Clifford with the water connections but not sure if I would want to get rid of it.

 

did you get a big hp increase,and what carb did you go with,is the eldebrock 500 cfm to much without a cam

 

I have not installed mine yet. I traded a gas tank for the clifford that I have. The motor I have needs rebuilt (brokem piston on the #2 cylinder) before I can put it on. The 390 holley works really well with the Clifford and Offenhauser intakes. The offenhauser dual port intake works a little better on the lower rpm's but both will help with performance. A 500 cfm could be a bit much for a 300. I know there has been some that have put on a 500 cfm 2 barrel.

 

I have a water heated Clifford 4 barrel intake with a Holley 390 and Clifford's 2 1/2" collector shorty headers. For my stock motor, this was a HUGE power increase. Of course, the stock stuff I took off is original to my '77 truck, and they leaked, burned out gaskets, etc. I love the new set up, especially on the highway when I punch it and the secondaries and power valve kick in. I never thought my old truck would come back to life like this!

IMO, without improving the internals in your motor, 500cfm would be too much. From everything I read before I decided on my setup, the 390 has the capacity to deliver the fuel mix that a stock motor would need under the heaviest conditions.

You can have my leaky old stock manifolds! :P

 

red77, any cam in that pick up truck?

 

Stock cam. Internals are all stock. I'm really happy with the bolt-on power that I got because it was cheap and easy for me to do by myself.