Yes they will, the 374's are the earlier style aluminum head found on the vette's and f body's, and are the more desirable for porting because of the more meat on them.


make sure the block you picked up is indeed the 350 LT1, and not the smaller "baby LT1", you probably know this, but the 350 LT1's are all stamped "327" on the side of the block, near the oil filter.:thumbsup:

 

Yes they will, the 374's are the earlier style aluminum head found on the vette's and f body's, and are the more desirable for porting because of the more meat on them.


make sure the block you picked up is indeed the 350 LT1, and not the smaller "baby LT1", you probably know this, but the 350 LT1's are all stamped "327" on the side of the block, near the oil filter.:thumbsup:

I thought it was the 643 heads that were the most desirable for porting.

 

Yeah I was sure to check that out before making the trip. It's got the "327" and also has a "GM 5.7" casting on the top near where it bolts to the tranny. Thanks for the head interchange info.

 

Well I won the heads, $180 total for the heads and shipping to my house. I don't have them yet but the pics look pretty good so I figure I got a good deal. Thanks for the help DJ_Kovacs.

 

i thought both the 374 and 643s are desirable. 561s are the ones with less meat

 

Ed Zachary right. 374's & 643's are the hot ticket when it comes to porting the factory castings. 561's flow better untouched, but have less meat and will flow less when fully ported.

 

I don't even think you can get 200 cc out of a 561 casting. This is a topic where a professional head porter will answer the long debated question.

 

I don't even think you can get 200 cc out of a 561 casting. This is a topic where a professional head porter will answer the long debated question.

So you are saying the NIGHTTRAIN66 is needed for this one.:notworthy

 

Yea, AI has a 200cc head package on stock heads out there.

 

I know that LLoyd has gobbled up 643 castings from people on other boards when offered for sale. Perhaps that is his personal choice. I'm sure he could say.

 

I know!! Back 2+ years ago when I was searching for a set of 643 or 347 casting he was buying every set in site! I remember one guy saying "Lloyd..how am I going to send you a set of heads when you keep buying them all!!" I had to go on Ebay and use a Buy It Now feature for a set of low mileage 374 casting heads to send him off of a 92 Vette for a healthy price.