I'm putting together a 406 for my 87 S10 Blazer, the engine came with 882 heads, these are known for cracking etc. What would be a good cast head to use or a lower cost aluminum head ? Mainly street use but will go to the track on occasion.
Heads for 406?
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Your going to have to pry the 882’s off to see what pistons are there and what is their deck clearance so the compression ratio can be calculated. Knowing the cam timing, especially where the intake valve closes in crankshaft degrees would be most helpful in computing the Dynamic Compression Ratio (DCR) if the cam is so big that compression ratio compensation need to be applied.
Most any aftermarket head will need to have steam holes drilled.
Keep in mind that aluminum head’s really need the block be zero decked so the head gasket thickness can be used to dial in the squish/quench clearance. This can be a problem with aluminum head’s because they like a thicker composite head gasket which is really needed with the steam holes, even a good idea with an iron head on these. So if your looking to optimize your build you need to do some basic research on what lies inside this beast.
The 882 is in the family of open chamber emissions head’s a caution here is although there are 74/76cc chambered modern aftermarket head’s these chambers are simply modern Ricardo chambers in the same contours as the the more typical 64cc chambered head’s as with the L31, Vortec head so these large chamber aftermarket head’s if they become necessary for compression ratio reasons offer the same power advantages as their smaller chambered siblings.
Aluminum is more tolerant of compression ratio error to the high side than is cast iron, With the 400’s bore this is a little more important to get things right than on the 350’s 4 inch bore. While the difference in bore doesn’t seem like much, the difference in burn sensitivity to the balls on dimensions is more critical on the 400 if you intend to push the power envelope.
Bogie
Most any aftermarket head will need to have steam holes drilled.
Keep in mind that aluminum head’s really need the block be zero decked so the head gasket thickness can be used to dial in the squish/quench clearance. This can be a problem with aluminum head’s because they like a thicker composite head gasket which is really needed with the steam holes, even a good idea with an iron head on these. So if your looking to optimize your build you need to do some basic research on what lies inside this beast.
The 882 is in the family of open chamber emissions head’s a caution here is although there are 74/76cc chambered modern aftermarket head’s these chambers are simply modern Ricardo chambers in the same contours as the the more typical 64cc chambered head’s as with the L31, Vortec head so these large chamber aftermarket head’s if they become necessary for compression ratio reasons offer the same power advantages as their smaller chambered siblings.
Aluminum is more tolerant of compression ratio error to the high side than is cast iron, With the 400’s bore this is a little more important to get things right than on the 350’s 4 inch bore. While the difference in bore doesn’t seem like much, the difference in burn sensitivity to the balls on dimensions is more critical on the 400 if you intend to push the power envelope.
Bogie
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Since you indicated lower budget, I would say a set of the good import casting aluminum heads, sold under a bunch of names as Bigmac73 said....ProHeader, Assault Racing/KMJ, Skip White/NKB, Race Parts Company/RPC and a slew more storefronts on Ebay.
Same casting AFR is using for their new as-cast no cnc head called the Enforcer. AFR just has it made with their 8mm guides so they can use their standard lightweight valves that they use in all their heads.
198-200cc intake port volume, 65-68cc chamber, 2.02/1.6" valve sizes. You can get a pair of bare castings for just under $400, Assembled pairs from $750 or so.
Next thing better would be ProMaxx Maxx Series 200cc
Then maybe the AFR Enforcer.
Putting a dime into rebuilding the 882's is a serious waste of time and money anymore.
Really need to know what the piston is and how far down from the deck it is at TDC....so you know what combustion chamber volume for the head you'll want to search for if you plan to use pump gas.
Same casting AFR is using for their new as-cast no cnc head called the Enforcer. AFR just has it made with their 8mm guides so they can use their standard lightweight valves that they use in all their heads.
198-200cc intake port volume, 65-68cc chamber, 2.02/1.6" valve sizes. You can get a pair of bare castings for just under $400, Assembled pairs from $750 or so.
Next thing better would be ProMaxx Maxx Series 200cc
Then maybe the AFR Enforcer.
Putting a dime into rebuilding the 882's is a serious waste of time and money anymore.
Really need to know what the piston is and how far down from the deck it is at TDC....so you know what combustion chamber volume for the head you'll want to search for if you plan to use pump gas.
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I went cheap with the above mentioned heads on my current 406.
ProFiler 220s will make lots more power. 200 cc runners are leaving lots of power on the table compared to 220s. I wish I didn't cheap out now, I really wish I would have saved the extra money for Profilers, but the motor still runs good with the cheaper heads and this cam. Straub Technologies
This cam was designed to work well with the Asian casting, and goes mid 12s in a 4000 pound truck.
Of course you really need to know what pistons you have. And the car its going in, and trans. And gears. Etc...
ProFiler 220s will make lots more power. 200 cc runners are leaving lots of power on the table compared to 220s. I wish I didn't cheap out now, I really wish I would have saved the extra money for Profilers, but the motor still runs good with the cheaper heads and this cam. Straub Technologies
This cam was designed to work well with the Asian casting, and goes mid 12s in a 4000 pound truck.
Of course you really need to know what pistons you have. And the car its going in, and trans. And gears. Etc...
First I want to Thank everyone for the replies.
We're going to use a flat top Piston, will need to run primarily on pump gas. Haven't decided on the cam at this time either. Mainly was wanting to know if there was a decent cast head or if I should be looking for a set of aluminum heads my brother has a 406 and he is using 64cc Dart Aluminum heads.
I have heard the 882 are not good heads so I wouldn't be putting any money in them
We're going to use a flat top Piston, will need to run primarily on pump gas. Haven't decided on the cam at this time either. Mainly was wanting to know if there was a decent cast head or if I should be looking for a set of aluminum heads my brother has a 406 and he is using 64cc Dart Aluminum heads.
I have heard the 882 are not good heads so I wouldn't be putting any money in them
The car is a 87 S10 Blazer, 700r trans (for now), 383 rear end
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I got a Dart top end kit from Summit for my 355 Chevy. Flat top Speed Pro pistons, CR is close to 10:1. 64cc, big valves and 7/16" rocker studs. I'm happy with the set up. It came with everything less the intake bolts.
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