Head Scratching l76 w ls1 heads
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Head Scratching l76 w ls1 heads Hey guys,
Have come across a bit of an interesting situation here with the planned rebuild for my car.
Now my car was running with an 02 ls1 it had some minor bolt ons, cam otr intake exhaust etc and after some abuse it popped, hurting a piston and bore pretty badly.
Now the heads are fine thankfully and me being a tight *** I want to get this repaired and running as quickly as possible.
In Australia where I am located availability of ls bottom ends is not nearly as plentiful and cheap as it is in the states but low and behold I have aquired a l76 short block low mile for a silly cheap price.
Now to my understanding it will require different head bolts to the original ones in my ls1 but will all transfer over accross reasonably easy.
I planned to disassemble the short block and replace the crank with my ls1 crank to be able to retain the 24x reluctor wheel and using the stock piston and rods give the motor a bit of a tidy up, new rigs bearings oil pump and Conrod bolts then put all my ls1 ancillaries and top end back on and get back to driving the damn thing.
Now the only questions I have are
1# I know the l76 l92 ls3 heads are a larger volume combustion chamber, and I am having trouble getting hard and fast figures on what my static compression would work out to with my stock 65cc ls1 heads on the l76 block with cometic 0040 gaskets, if anyone has experience with this I would be very appreciative.
2# will I be able to retain my ls1 aftermarket camshaft ? As it was a very nice cam and it would save my buying a new one.
3# is there any other issues that may present themselves to bite me in the *** in the future ??
Thanks in advance guys much appreciated
Have come across a bit of an interesting situation here with the planned rebuild for my car.
Now my car was running with an 02 ls1 it had some minor bolt ons, cam otr intake exhaust etc and after some abuse it popped, hurting a piston and bore pretty badly.
Now the heads are fine thankfully and me being a tight *** I want to get this repaired and running as quickly as possible.
In Australia where I am located availability of ls bottom ends is not nearly as plentiful and cheap as it is in the states but low and behold I have aquired a l76 short block low mile for a silly cheap price.
Now to my understanding it will require different head bolts to the original ones in my ls1 but will all transfer over accross reasonably easy.
I planned to disassemble the short block and replace the crank with my ls1 crank to be able to retain the 24x reluctor wheel and using the stock piston and rods give the motor a bit of a tidy up, new rigs bearings oil pump and Conrod bolts then put all my ls1 ancillaries and top end back on and get back to driving the damn thing.
Now the only questions I have are
1# I know the l76 l92 ls3 heads are a larger volume combustion chamber, and I am having trouble getting hard and fast figures on what my static compression would work out to with my stock 65cc ls1 heads on the l76 block with cometic 0040 gaskets, if anyone has experience with this I would be very appreciative.
2# will I be able to retain my ls1 aftermarket camshaft ? As it was a very nice cam and it would save my buying a new one.
3# is there any other issues that may present themselves to bite me in the *** in the future ??
Thanks in advance guys much appreciated
your LS1 crank will be factory balanced to a lighter bob weight. Since the new pistons do weigh more, the crank may need slugs of Mallory(heavy Metal) in order to correct the balance. these pieces are both expensive to purchase as well as install.
There are some additional difference between the L76 block and the LS1 block. Knock sensor location, camshaft position sensor location for example.
You could use your existing cam as long as you can convert to using the front cover cam position sensor location.
Quick calc assuming 6.098 rod and 3.622 stroke with 4.00 bore and 65cc heads yields a 11.36:1 static compression with .040 gaskets. (also assuming pistons come out of the hole a stockish ~.006)
You could use your existing cam as long as you can convert to using the front cover cam position sensor location.
Quick calc assuming 6.098 rod and 3.622 stroke with 4.00 bore and 65cc heads yields a 11.36:1 static compression with .040 gaskets. (also assuming pistons come out of the hole a stockish ~.006)
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From: Wilmington, De
You would be better off having a machine shop change the reluctor on the L76 crankshaft. Otherwise, you will need to have the LS1 crank rebalanced. Over in the States, it costs about $75 to have it done.
You will also need to pick up a 3 bolt, 1X camshaft timing gear for the engine.
Aside from that, you will need to drill and tap the sides of the block for the Gen III knock sensors, and get knock sensor and camshaft position sensor extensions. Make sure you get new Gen IV lifter trays and the later head bolts that are all the same length. Other than that, the cam, heads, accessories, and such from your LS1 will still work.
You will also need to pick up a 3 bolt, 1X camshaft timing gear for the engine.
Aside from that, you will need to drill and tap the sides of the block for the Gen III knock sensors, and get knock sensor and camshaft position sensor extensions. Make sure you get new Gen IV lifter trays and the later head bolts that are all the same length. Other than that, the cam, heads, accessories, and such from your LS1 will still work.
