Heads? Cast or Aluminum?

I picked up a set of aluminum head for next to nothing, questions are do the aluminium head swap? Get the cast ones worked on? (4 bolts broke off flush in the head)

I do have plans on dropping a comp cam in, kit number: K07-466-8 [You must be registered and logged in to see this link.]

Would love some advice on which way to go in this.

Thanks as always!

A word of advice, I was going to go with that cam myself, but it will require quite a bit of ecm tuning and a new map sensor. There was a discussion on Thirdgen that offered alternatives.

Can ya get me a link? What did you end up running cam wise?

You may need a larger TBI, and injectors. I have a rebuilt 46mm TBI. The manifold must be reamed out to match the 46mm TBI.

The heads may have a different angle at the intake manifold. You have to check it before you go any further.

Some have put the 9C1 (LO5) or LT1 cam in the LO5. If you use the computer and injectors from the 9C1 (LO5) it is a bolt up to the block. The LT1 cam may require a different tune. I am not sure how the heads will affect the tune even if they fit with the OEM manifold.

My bad Fred, this question is for my 96' RMW...

I'm at a standstill on what to do now with the whole head situation and with this cam...

The angler on the heads is critical to mate up with the manifold. I learned the hard way.
I'm running a similar cam but 230/236@ 0.050. It's a beast.

As Fred said, the expectation is to reprogram. Welcome to my world. I use the EBL system from Dynamic EFI an TunerproRT as the software.

lakeffect wrote:

The angler on the heads is critical to mate up with the manifold.  I learned the hard way.
I'm running a similar cam but 230/236@ 0.050. It's a beast.

Anyone know about how the aluminum heads need worked?

Any what's up with that part number for that cam lol?

various opinions on lt1 aluminum heads,. the iron heads actually flow a little better but the aluminum heads disperse heat better so you can run a wee bit more timing,.

cam selection is like soup,.. etc,...

I'd hop over to the ISSF forum and do some research, I'm sure this has been argued to death over there. From what I understand LT1s have the same intake regardless of head type, but don't quote me on that lol.

If his signature is any clue, unless i am missing something here, on an "93 wagon", it would be a conventional small block, not an LT1a

Boomhauers_93Wagon wrote:

My bad Fred, this question is for my 96' RMW...

Ah. Well then my cam suggestions wont be any help then. Thought this was for a tbi.

My bad as well, didn't catch that one. I'm not a LT1 owner, so I'll bow out of this one.

My first wagon was a 93' Caprice then I picked up a 96' RMW...

But thanks for the help guys...

As Nick pointed out the cast heads flow better as they were designed later than the aluminum heads if stock. If you are going to get them ported and / or larger valves then most folks go with Aluminum heads. There are two casting numbers that are best for porting as they have more meat. The 673 heads (end of casting number) are very popular. If you change the heads I suggest valve springs. The Beehive COMP CAMS springs do a great job and will require new keepers and locks. There is a plethora of cams out there. I have the 2033 profile Crane cam (referred to as the 227 cam) in my car and like how it acts. My Impala SS has a 503 cam that is a lot of fun, but poor fuel mileage. The GM LT4 Hot Cam is also very popular. Again read on the Impala SS forum they have a TON of info on cams. A new timing set is a good idea as well. Roller Rockers are nice, but not really necessary. The Hot Cam is designed along side of 1.6 rockers, but as long as you do the right valve springs roller rockers can be added anytime. If you want a turn key package of heads and cam Lloyd Elliott is known as the expert at this type of kit. Tell him your goals and he will build a kit for you.

Read a lot and believe 1/2 of what you read. Good luck.

Just for conversation the aluminium LT1 heads I have got the #: 10207643 on em...

Try to stir my memory.   Not sure 673 was the right number.   I know 643 is and 374 might be the other casting number.   A quick trip to the impala forum would confirm this.