6 bolt heads on 4 bolt block.
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Teching In
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6 bolt heads on 4 bolt block. First off, my apologies if this is the wrong area. I was unsure if internal meant short or long block.
I have not found any information on interchange of heads on blocks. I know that the LSX 6 bolt block takes either 4 bolt heads or 6 bolt heads, but is it possible to go the other way and use the 6 bolt heads on the 4 bolt block? I have looked at them and it APPEARS that they SHOULD, but I do not know, and would be very mad if I spent $2600+ on heads and then couldn't use them. So, can this be done, and if so is anything special required? Like would I have to have the fifth and sixth bolt holes on the heads milled off for any reason or anything weird?
Thanks in advance!
P.S. Don't ask why, that's not the point.
I have not found any information on interchange of heads on blocks. I know that the LSX 6 bolt block takes either 4 bolt heads or 6 bolt heads, but is it possible to go the other way and use the 6 bolt heads on the 4 bolt block? I have looked at them and it APPEARS that they SHOULD, but I do not know, and would be very mad if I spent $2600+ on heads and then couldn't use them. So, can this be done, and if so is anything special required? Like would I have to have the fifth and sixth bolt holes on the heads milled off for any reason or anything weird?
Thanks in advance!
P.S. Don't ask why, that's not the point.
Because you can buy the best heads you can afford, once! Then when you have the coin to upgrade the short-block to a 6-bolt block, you already have the heads and just need the head bolts/studs and you're ready to rock without spending another $2000+ for heads!
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Thanks.
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Is it possible to modify a 4 bolt block to use all the 6 bolt head studs? For example, take the 4 bolt block and machine the extra 2 holes needed for the 6 bolt head. This way you don't need to buy a new block and will have the clamping force by using all 6 bolts? I'm not sure where they put the extra 2 bolts, but seems like if there is enough meet in the block it would be a feasible and cost effective way to add more clamping force.
Thread Starter
Teching In
Joined: Dec 2010
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You do!? Okay, why not?
Let's wait and see if he is right.
Is it possible to modify a 4 bolt block to use all the 6 bolt head studs? For example, take the 4 bolt block and machine the extra 2 holes needed for the 6 bolt head. This way you don't need to buy a new block and will have the clamping force by using all 6 bolts? I'm not sure where they put the extra 2 bolts, but seems like if there is enough meet in the block it would be a feasible and cost effective way to add more clamping force.
Nice try, though.
Take a look at these for reference.
LS3 Block - note the bosses on the intake side that are lacking on the the outer side of the block and also on the front and rear cylinders.
LSX Block - look at the location for the extra two bolts per cylinder.
Is it possible to modify a 4 bolt block to use all the 6 bolt head studs? For example, take the 4 bolt block and machine the extra 2 holes needed for the 6 bolt head. This way you don't need to buy a new block and will have the clamping force by using all 6 bolts? I'm not sure where they put the extra 2 bolts, but seems like if there is enough meet in the block it would be a feasible and cost effective way to add more clamping force.
Thread Starter
Teching In
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I would like to know more about how you did this and was it just for the purpose of the extra clamping force?
I'm actually curious how much it cost to modify the aluminum LS2 block (weld/heat treat/drill/tap) and then do all the other typical machine work that any high end build requires...I really haven't seen many strength related bottom end failures in the aluminum blocks, especially not when fitted with billet main caps...if it's a more attractive price than an LSx thats cool...plus it weighs less, which is the attraction of the Warhawk over the LSx...but again, that one costs a lot too...I'm guessing the procedure would be mostly the same for any other production aluminum block, maybe just slightly different prep work to the original casting if it's shaped slightly different (like the 6.2 pictured above with the 2 bosses near the lifters that'd need to be modified)...granted I'm sure there are bottom end strength benefits to the LSx and Warhawk that won't be seen in a modified production block...but for lower 4 digit power builds, they're probably not necessary for a lot of those builds.
