1966 327???
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From: Kannapolis, NC
1966 327??? My brother has the option of purchasing a 327 2 bolt main for his 92 Z28. He had a few questions.
1 how far can it be bored?
2. Can we get more stroke out of it to achieve something like a 402 since the bore is around 4.
Are the mounting holes for the accessories the same as a 305/350
and what are options for these motors such as heads cam headers?
He can pick it up complete for 150 but needs to be rebuilt but he doen't want something that is going to be worse than just getting a 383 and being done with it where you can slap almost any set of heads on it. We did not know the kind of options that are available for a 327. Let me know what you guys think. Thanks for the help.
1 how far can it be bored?
2. Can we get more stroke out of it to achieve something like a 402 since the bore is around 4.
Are the mounting holes for the accessories the same as a 305/350
and what are options for these motors such as heads cam headers?
He can pick it up complete for 150 but needs to be rebuilt but he doen't want something that is going to be worse than just getting a 383 and being done with it where you can slap almost any set of heads on it. We did not know the kind of options that are available for a 327. Let me know what you guys think. Thanks for the help.
327 Block Pre-86 SBC cases have different oil pans to accommodate the dipstick location and rear main seal configuration. Really early cases (probably this 327) have a provision for a road draft tube. The crank flanges are different with regards to the rear main seal and flywheel bolt pattern. Otherwise, most everything (except for the reverse-cooling stuff) will fit.
If he wants to go big, he would be better off with a 400 SBC. I'm partial to the 509 case, even though it's a two-bolt main. The caps have a wider base than the normal two-bolt SBC configuration and there is more meat in the main web in the block. You can dowel (use SBC head dowels) the caps and block for more strength also. These blocks are still out there but you have to beat the bushes for them.
A good one will go .060 (with sonic testing) but I wouldn't personally go beyond .040 (4.165), which will give you around 408 cubes with the stock 3.76 stroke. The 408 case, with a set of DART II 200 Sportsman heads is a killer (and economical) combo on a TPI engine with the right cam/induction combo.
You can also go to a 3.875 stroke (4.165 x 3.875 = 422.36
) without too much discomfort.
Otherwise, a 383 would trump the 327 any day by virtue of being able to use the factory roller cam case and hardware, saving you big bucks.
If he wants to go big, he would be better off with a 400 SBC. I'm partial to the 509 case, even though it's a two-bolt main. The caps have a wider base than the normal two-bolt SBC configuration and there is more meat in the main web in the block. You can dowel (use SBC head dowels) the caps and block for more strength also. These blocks are still out there but you have to beat the bushes for them.
A good one will go .060 (with sonic testing) but I wouldn't personally go beyond .040 (4.165), which will give you around 408 cubes with the stock 3.76 stroke. The 408 case, with a set of DART II 200 Sportsman heads is a killer (and economical) combo on a TPI engine with the right cam/induction combo.
You can also go to a 3.875 stroke (4.165 x 3.875 = 422.36
) without too much discomfort.Otherwise, a 383 would trump the 327 any day by virtue of being able to use the factory roller cam case and hardware, saving you big bucks.
It's a small main journal, '69 was the only year for large journal. So you're stuck with the 327.
It probably has no accessory bolt holes in the heads, if it does all the external parts will fit including the reverse rotation water pump and all of it's brackets, even if the heads have accessory holes there will be one missing on the passenger side. As said the flexplate/flywheel is different.
If it has the original heads there will be one exhaust bolt hole missing, older heads have six exhaust bolt holes, later model and especially f-body small block heads have 7 holes per side. This is only for use with stock manifolds.
It probably has no accessory bolt holes in the heads, if it does all the external parts will fit including the reverse rotation water pump and all of it's brackets, even if the heads have accessory holes there will be one missing on the passenger side. As said the flexplate/flywheel is different.
If it has the original heads there will be one exhaust bolt hole missing, older heads have six exhaust bolt holes, later model and especially f-body small block heads have 7 holes per side. This is only for use with stock manifolds.
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Joined: Jul 2005
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From: Lombard,IL
i wouldnt bother stroking it, build that motor right and it should be able to rev to 9,00rpm or more. if its a 66 it may have camelhump heads, which like stated above has no accessory holes. what size are the valves on the head? 327 and 302 are getting to be pretty rare. if i had that motor i would just make the thing rev to the moon.
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Originally Posted by scatillac
Pre-86 SBC cases have different oil pans to accommodate the dipstick location and rear main seal configuration. Really early cases (probably this 327) have a provision for a road draft tube. The crank flanges are different with regards to the rear main seal and flywheel bolt pattern. Otherwise, most everything (except for the reverse-cooling stuff) will fit.
If he wants to go big, he would be better off with a 400 SBC. I'm partial to the 509 case, even though it's a two-bolt main. The caps have a wider base than the normal two-bolt SBC configuration and there is more meat in the main web in the block. You can dowel (use SBC head dowels) the caps and block for more strength also. These blocks are still out there but you have to beat the bushes for them.
A good one will go .060 (with sonic testing) but I wouldn't personally go beyond .040 (4.165), which will give you around 408 cubes with the stock 3.76 stroke. The 408 case, with a set of DART II 200 Sportsman heads is a killer (and economical) combo on a TPI engine with the right cam/induction combo.
You can also go to a 3.875 stroke (4.165 x 3.875 = 422.36 ) without too much discomfort.
Otherwise, a 383 would trump the 327 any day by virtue of being able to use the factory roller cam case and hardware, saving you big bucks.
If he wants to go big, he would be better off with a 400 SBC. I'm partial to the 509 case, even though it's a two-bolt main. The caps have a wider base than the normal two-bolt SBC configuration and there is more meat in the main web in the block. You can dowel (use SBC head dowels) the caps and block for more strength also. These blocks are still out there but you have to beat the bushes for them.
A good one will go .060 (with sonic testing) but I wouldn't personally go beyond .040 (4.165), which will give you around 408 cubes with the stock 3.76 stroke. The 408 case, with a set of DART II 200 Sportsman heads is a killer (and economical) combo on a TPI engine with the right cam/induction combo.
You can also go to a 3.875 stroke (4.165 x 3.875 = 422.36
) without too much discomfort.Otherwise, a 383 would trump the 327 any day by virtue of being able to use the factory roller cam case and hardware, saving you big bucks.
Also, this would be a small journal engine.
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Originally Posted by 8a8mfh
It's a small main journal, '69 was the only year for large journal. So you're stuck with the 327.
It probably has no accessory bolt holes in the heads, if it does all the external parts will fit including the reverse rotation water pump and all of it's brackets, even if the heads have accessory holes there will be one missing on the passenger side. As said the flexplate/flywheel is different.
If it has the original heads there will be one exhaust bolt hole missing, older heads have six exhaust bolt holes, later model and especially f-body small block heads have 7 holes per side. This is only for use with stock manifolds.
It probably has no accessory bolt holes in the heads, if it does all the external parts will fit including the reverse rotation water pump and all of it's brackets, even if the heads have accessory holes there will be one missing on the passenger side. As said the flexplate/flywheel is different.
If it has the original heads there will be one exhaust bolt hole missing, older heads have six exhaust bolt holes, later model and especially f-body small block heads have 7 holes per side. This is only for use with stock manifolds.
All small journal (up to 67 MY) 3.25" cranks were forged. Only Hi-Perf large journal 327 cranks were forged. All 307 cranks were cast.
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Originally Posted by rjkZ28
i wouldnt bother stroking it, build that motor right and it should be able to rev to 9,00rpm or more. if its a 66 it may have camelhump heads, which like stated above has no accessory holes. what size are the valves on the head? 327 and 302 are getting to be pretty rare. if i had that motor i would just make the thing rev to the moon.
Here is the most common "HI-Perf" head part number for 66: 3890462 had a double hump casting mark externally but could be either 1.94/1.50 or 2.02/1.60 depending on application. Both heads had a 160cc intake runner as well as a 64cc combustion chamber volume.
Source: http://www.mortec.com/castnum.htm
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Verdad Gallardo 12 Second Club
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FYI: You CAN build a 327 large journal 4-bolt main engine. I used a 68 forged large journal crank in an 010 4-bolt block. The roller cam I used (this was mid-80's) had a reduced base circle and would make power from 3500 to 7500 rpm. Of course I had a ton of money into the heads (291's w/2.02 and 1.60, studs, guide plates, stud girdle, roller rockers - you get the point) to stabilize the valvetrain at that rpm. I also deburred the block, epoxied trash traps Glyptaled the inside and used ARP studs everywhere. Had a rev kit on it also. I spent quite a few hours blue printing the assembly of that engine.
