Will the 305 heads be alright to use of i left the stock 1.84 intake valve in it.
Thank you

 

You can run them with the small valves, yes. I don't think you'll gain anything with the raised compression vs. a larger cc bigger valve head unless you do some porting. If you do go bigger put 1.94 race/street flo's in, 2.02's would take alot of grinding to be any advantage and not worth anything over the 1.94.

 

Like stated above, ignore the 2.02 thing. It's not a matter of grinding. 2.02/1.6 valves fit in a 4.000 bore no matter what. Valve deshrouding is a nother story. But, the biggest thing would be the velocity. Unless you REALLY work them over, there are no gains by switching to 2.02 on the intake side. In fact, it may hurt velocity.

For a 350, the 1.94 intake valve really is somewhat needed. I'm sure you can get away with 1.84, but you are limiting your engines power potential.

If they're coming off, why not run them to the shop and have them cut for 1.94/1.6?

 

OK cool. What kinda performance will I see from just putting in the 1.94 valve and not porting.

 

What a wonderful topic! I just spent seven months and over $1500 in order to produce a good set of stock castings . Four pairs of heads later...

I put a set of '601 heads on my L98 350. I had them cut for 1.94/1.60 valves, larger valve springs, guide plates, and screw-in studs. My machinist also deshrouded the valves somewhat. The compression ratio is now about 10.2:1 versus the factory 9.3:1 (for an '87 L98).

I can't really say how they're working, because I just got my car fired up for the first time tonight. Just for comparison, I did two profiles of my engine in Desktop Dyno -- one with fully ported L98 heads and one with fully ported '601 305 heads. While the 305 heads didn't flow as much, the extra compression caused them to make a bit more power. I know that DD isn't completely accurate, but it's decent for predicting the change incurred across various configurations.

I would not recommend putting 305 heads on a 350 without porting them first. It's kinda like a step forward and a step backward at the same time -- sure, you're raising the compression ratio, but you're putting on a lower-flowing head. Head porting isn't all that difficult, but it takes some time to learn your way around. I've gotten my time down to three hours per head, but that's because I've done it so many times. Try searching the archives for some information on it.