GM 4.3 V6 conversion
12-09-2004, 02:53 PM
#11
Senior Member
Certified GM nut
Join Date: Feb 2003
Location: Georgia
Posts: 2,095
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by 1993 SLE
Couldnt you stroke a 3.8? that would be sweet
12-09-2004, 03:09 PM
#14
Senior Member
Certified Car Nut
Join Date: Oct 2003
Posts: 19,756
Likes: 0
Received 0 Likes
on
0 Posts
ok so the kit is for the S1 but im not sure that i understand........it looks like there is alot of more internal parts that need to be changed..........Correct?
12-09-2004, 03:15 PM
#15
Senior Member
Certified GM nut
Join Date: Feb 2003
Location: Georgia
Posts: 2,095
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by 1993 SLE
ok so the kit is for the S1 but im not sure that i understand........it looks like there is alot of more internal parts that need to be changed..........Correct?
In the post:
Originally Posted by DrJay
So I got some word back today, here'* whats up so far. (to save typing time some stuff is taken word-for-word)
[It] has a stroke increase from 86.36 to 96mm, with a .020" over bore that equates to 4.258L capacity, or 4.302L with a .040" over bore. The extra stroke makes a huge difference to power produced, without the need for high revs and rough low-speed running. A 35% increase is readily available.
The rods are standard Series I (with some mods, more info later) but its recommended you use the Series II pistons because they're hypereutectic or forged is always better.
Adjacent big end journals on these cranks have a 30 degree offset. To strengthen this area engineers advise thickening the flange between the journals from 3mm to 4mm. This increases shear resistance by approximately 20% and that radiused journals give a similar degree of added strength over under cut journals. Both features are incorporated into these cranks.
Heavier counter balancing webs are designed for easy balancing before final assembly. once piston and rod weights have been established, fit your harmonic balancer and flexplate and the balancing can be done. We are not in the engine reconditioning business and have designed the crankshaft for economical engine rebuilding by the mechanic of your choice.
[It] will reach TDC approximately 4mm from the deck and give a CR of about 9.2:1
A test motor fitted with one of these cranks has successfully run at 7000rpm
This crankshaft is not intended for high revs. With the 11% longer stroke, piston speeds and the piston and conrod accelaration/deelaration forces make unreasonable demands on the production components we suggest for this conversion.
Some internal clearancing at the cylinder block is neccessary, adjacent to the connecting rods. take care at the oil gallery.
The rest is normal V6 assembly.
standard V6 125-130BHP @ the wheels
test car with 4.3 stroker 177 BHP @ the wheels
[It] has a stroke increase from 86.36 to 96mm, with a .020" over bore that equates to 4.258L capacity, or 4.302L with a .040" over bore. The extra stroke makes a huge difference to power produced, without the need for high revs and rough low-speed running. A 35% increase is readily available.
The rods are standard Series I (with some mods, more info later) but its recommended you use the Series II pistons because they're hypereutectic or forged is always better.
Adjacent big end journals on these cranks have a 30 degree offset. To strengthen this area engineers advise thickening the flange between the journals from 3mm to 4mm. This increases shear resistance by approximately 20% and that radiused journals give a similar degree of added strength over under cut journals. Both features are incorporated into these cranks.
Heavier counter balancing webs are designed for easy balancing before final assembly. once piston and rod weights have been established, fit your harmonic balancer and flexplate and the balancing can be done. We are not in the engine reconditioning business and have designed the crankshaft for economical engine rebuilding by the mechanic of your choice.
[It] will reach TDC approximately 4mm from the deck and give a CR of about 9.2:1
A test motor fitted with one of these cranks has successfully run at 7000rpm
This crankshaft is not intended for high revs. With the 11% longer stroke, piston speeds and the piston and conrod accelaration/deelaration forces make unreasonable demands on the production components we suggest for this conversion.
Some internal clearancing at the cylinder block is neccessary, adjacent to the connecting rods. take care at the oil gallery.
The rest is normal V6 assembly.
standard V6 125-130BHP @ the wheels
test car with 4.3 stroker 177 BHP @ the wheels
<---guess i should read
