520T heads ???
 

what is the difference bewtwwen 520 T heads and a "normal" 520 head??? Must be a performance diff right???

Re: 520T heads ???
 

I think the 520T has more material for porting. All the super stock motors have the 520T. Better head all around for SS.

Re: 520T heads ???
 

OK ....(not to steal the thread) so what is better the "T" head or "Canadian" head?

Re: 520T heads ???
 

tonowanda

Re: 520T heads ???
 

What he said I was told the T head is better for stock because the ports are bigger?!?!?
Never tried them maybe next year..

Re: 520T heads ???
 

Greg what is the canadian head numbers?? They use to have a nice belmont at Brainerd International Raceway u know the cross between a GTO and A Chevelle it was a 66 or 67

Re: 520T heads ???
 

Per Garley Daniels back in the day , the Canadian head is the best. He said there were around 1,000 sets made . That is what he tried to run back in the superstock days.. They have CANADA stamped inside nect to valve springs, and best i remember they are 520 castings. I have a set (formally Garley heads) at Greg's and he can check for id on them.

Re: 520T heads ???
 

Here's a different perspective since I have flowed over 100 different 520 cylinder heads over the years. Back "in the days" there were some ingenious folks who understood the psychology of numbers and their effect on the racer's mind. Sometimes a truly odd part in a common pile could be personally modified for an advantage and then the superiority be attributed to its oddness. If most everybody's 520 heads were 130 cc and yours were 140 cc, the argument is easier to swallow if yours have markings that indicate a different origin. That's not always true, but cases like the 461X heads can be used to further substantiate a new legend. However, 'T' heads are consistently a good choice, if you get my drift.

Re: 520T heads ???
 

OK so ya try to psych em out huh???--anyway we have both 520 USA heads 520T heads and a pair of Canadian 520 heads available---of the 3 heads which head "might" be the best head performance wise and which head would you flow first to see if it is/was better than the other 2--follow your thinking on the 461x vs 461 head can see the difference there, there is definately a difference in the port sizes but is there a disimilarity between the 3 "types" of 520 heads even tho they all carry the same part number or is it just something imagined. thanx FED387

Re: 520T heads ???
 

I had my cylinder head guy flow several of both the 520t and 520T. Either are satisfactory as a starting point, for Stock. The large T is slightly larger on cc's and will more than likely have to be cut back on the intake runner side to get it under 140cc's, that's as originally cast. So far, EVERY 520T I have poured has been too big and needed this done. Depending on style of valve, etc, you may have to machine off more.

Wade