SBF heads on 300 six

[john-dickjr]

i have a nice set of cast iron heads that i ran on my 347 motor, 2.05 valves--1.65 exh..flowed 308 intake --246 ex..if i can find enough info on this i would attempt to use these on my 300 ford..if anyone has info on this, links..pictures..tech ..anything , please pm me or post it here..heads are normal valve layout, not Cleveland type..

 

[Does10s]

Unfortunatly the bore spacing isn't the same. So the SBF heads won't fit on a 300.

However, LSX heads do have the same bore spacing.

Will

 

[john-dickjr]

Unfortunatly the bore spacing isn't the same. So the SBF heads won't fit on a 300.

However, LSX heads do have the same bore spacing.

Will

then how do they use a 351c head on a 302, and a 300 straight 6?

 

[StrangeRanger]

They cut the center piece a bit long and end up with combustion chambers which are not perfectly centered on the bores.

The bore spacing on an SBF is 4.380", it's 4.480" for the 300. If everything gets put together properly, the 1/2, 3/4 and 5/6 pairs are .010" too close together and the gaps between 2/3 and 4/5 are both .010" too far, so each chamber is off by .005"

 

[rocklord]

The biggest problem you have with cast iron heads is welding them together.

The LSx heads are aluminum, so they would be easier to piece.

 

[russk]

Guys:

I may be wrong but back in the 70s (?) when Bruce Sizemore built his IL6 head, I believe he used six individual sections of a 351C head that were furnace brazed. If I'm remembering correctly, using six pieces allowed him to deal with the differing bore center distances. I seem to recall he had problems keeping the damper on the crank snout. In any event, it was a screamer ...

Russ

 

[otto69]

Hi Russ
Many years ago I stumbled across a 2 page article on a very similar head. With no other info I found 5 x 2V closed chambered Cleveland heads and cut them up, machined them so the chambers where centred over the bores. Milled the exhaust side to accept a high port plate and even made up a 6 gas burner that fitted in the bores to heat the head before welding. But at the time I could find a good cast iron welding rod to finish it.

Its still in the shed, along with many other half finished projects

It was at this stage that I found another article using SVO heads, that would be nice


Clayton

 

[drag-200stang]

where's the post by otto69? I can't see it.

 

[THE FRENCHTOWN FLYER]

They cut the center piece a bit long and end up with combustion chambers which are not perfectly centered on the bores.

The bore spacing on an SBF is 4.380", it's 4.480" for the 300. If everything gets put together properly, the 1/2, 3/4 and 5/6 pairs are .010" too close together and the gaps between 2/3 and 4/5 are both .010" too far, so each chamber is off by .005"

If you cut off three chambers then center up 2 and 5 then #1, #3, #4, #6 are actually off .100" ,not .005"

Plus the valve arrangement is backwards from a conventional cam. This has been discussed many times before and there are several threads on the topic.