intake for 305 heads?

[74chev4x4]

Hey guys have a quick question.  I just bought a small block 350 with 305 heads(75-79) and I am on summitracing buying some parts for it and want to get a new intake manifold.  Do I need one for a 305 or 350 because I thought all small blocks were the same, but when I look for the 350 intake it says only for the 350, 400, and 4.3L motor.  Any help would be great.

[Irish_Alley]

why not put bigger heads on it?

[74chev4x4]

I bought it that way, just wanted a nice 350 for my truck, didn't know they were 305 heads until I pulled the valve covers guess they are the 60cc ones.  The guy that had the motor before said it was a really torquey motor so I hope it will be fine, I know everyone says its not as good with the 305 heads?

[eventhorizon66]

There are three different intake styles for the Gen 1 SBC - Traditional (6 intake bolts per side, all perpendicular with intake face), 87-95 iron head (6 bolts per side, middle two angled upward as installed on engine), L31 Vortec (4 bolts per side flanking the water ports, vertical as installed on engine).  All stock heads (with the exception of L31 vortec) have about the same intake port dimensions.  So if the bolt pattern is the same the intake will directly interchange.  Due to manufacturing variances a slight mismatch may occur, so you might want to check port alignment.

The reason I think 305 heads gained a small cult following was they were a cheap bolt on compression increase.  With a stock cam engine, the loss of flow may be offset by the increase of power from compression.  But in anything more than a stock cammed 350, 305 heads have no merit.  They have smaller valves and weaker ports than even the abysmal -882 heads.  If you want performance on a budget grab a set of L31 vortec heads (which, as I mentioned earlier, will require a different intake).

[74chev4x4]

what am I looking at price wise for those vortec heads?

[74chev4x4]

this motor does have a small aftermarket cam, nothing much though, does that hurt performance with these heads?

[eventhorizon66]

Not necessarily recommending this vendor or sale, but here's an example of what you can find (notice he's selling it "as is"; some vendors offer guarantees and warranties for more money):

http://cgi.ebay.com/ebaymotors/CHEVY-350-5-7L-REMANFACTURED-VORTEC-HEADS-062-1996-2000-/220600034827?cmd=ViewItem&pt=Motors_Car_Truck_Parts_Accessories&hash=item335cc9660b

And they'll require an intake such as this:

http://www.summitracing.com/parts/PFS-52028/

this motor does have a small aftermarket cam, nothing much though, does that hurt performance with these heads?

The 305 heads are hurting performance with that cam, not the other way around.  It really depends on how much you value "performance".  But I've never heard of a respected performance engine builder advocating the 305 heads as a performance item.

[74chev4x4]

So I would be looking at new intake head gaskets and pushrods?  I have built a few toyota motors, but never a v8, I know I can do this, but I get comfused with setting the valves and pushrods back correctly.

[74chev4x4]

The guy I got it from had it in a 73 chev 4x4 and said it had lots of torque, I just want a nice small block that will be good for my truck!

[eventhorizon66]

The guy I got it from had it in a 73 chev 4x4 and said it had lots of torque, I just want a nice small block that will be good for my truck!

Well you could always try it out and see how happy you are with it first.  That could potentially save you alot of money and effort.

Here's is one of the best domestic V8 engine building guides out there:

http://store.boxwrench.net/Basic-Engine-Building-DVD_p_8.html

[74chev4x4]

yea I think I might do that, kind of a bummer for the 305 heads, But I can try it out, thanks!

[eventhorizon66]

Best of luck

[Josh454]

Run the 305 heads.  You might not make 400 HP but for the application you have now they will be fine.  Save your money on the intake and stick it away for the L31's when you get the time and money.  Then you can do a cam and head swap at the same time.