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Discussion in 'L: Horizon/Omni, Rampage, etc' started by theborg0, Dec 25, 2015.
Can I bolt a 2.2 turbo crank into a non turbo block of the same year?
Yes, it is the difference of a cast and a steel crank, bearings are the same size but I believe they may be a different material, use the Clevite 77 bearings, which are a better tri-metal blend and I believe used in the turbo engines to begin with.
Thanks a bunch!
You can run into problems with 1985 engines. There was a running change from 6 bolt to 8 bolt flywheels along with 10 mm to 11 mm head bolts. Very few turbo engines had steel cranks, most were cast.
Wasn't that the change from the 2.2/2.5 to the "common block" upgrade where the same block is used but the stroke was changed? Or was that 1989? I thought, also, the turbo engines got the steel cranks and not the cast/nodular steel cranks. Either way, other than the bolt change, they interchange to the best of my knowledge.
2.2L/2.5L Turbo 1's had nodular cast iron cranks and 2.2L/2.5L Turbo 2 had forged steel cranks.
1989 was the year of the common block.
OK, Fast Eddie, but do the cranks interchange from the high 2.5/low 2.2 block with the common block, other than the bolt difference? I believe they do. A cast/nodular steel crank is good for an easy 300hp, so that isn't an issue.
I am pretty sure they do.
As mentioned the 2.2 changed during 1985.
1981-1985, 6 bolt cranks interchange and 1986-1988, 8 bolt cranks interchange.
1981-1985 all 2.2's used stronger pressed pin rods, 1986-1988 all but T-II's used light weight pressed pin rods.
The tall deck 2.5 was built from 1986 to 1988, all were TBI, none were turbo.
They all used a 4.09" stroke cast crank, 2.2 turbo pistons and longer light weight pressed pin connecting rods.
The common block was introduced for the 1989 model year.
2.2 and 2.5 blocks and connecting rods were interchangeable but the piston deck height differed to accommodate the different stroke. Non turbo engines used light weight pressed pin rods but 2.2 and 2.5 Turbos used stronger full floating rods. Crank/cam sprockets were now all round tooth and water pumps were reverse rotation.
Cranks are not easily interchangeable between common and non common blocks due to different snouts.
The only steel cranks were 2.2 T-II (1987-88) non common, 1989 2.2 T-II common and 2.2 T-III and 2.2 T-IV, both common.
2.5 TBI and Turbo cranks were all cast. There were two 2.5 tall deck cast cranks, 1986-87 and 1988, and they can fit a common block if their specific seal retainers and crank pulleys are also used.
2.5 Turbos were all cast crank T-I's, non intercooled, except Mexico had a cast crank intercooled 2.5 Turbo.
OK, so then the next question is, just because the snout is different, as long as the front balancer/counterweight/belt/chain sprocket/belt cog is used, it should bolt in. They also, about this time, changed from square to round belt cogs, too, and as far as I know they interchange and are more durable, don't get chewed up as much as the square tooth belts, so that would be another good upgrade.
The crank will fit into the block but it's the front seal retainer area that is the problem.
The front of the common block was recessed to accommodate the balance shaft assembly front seal retainer.
Due to this, the seal retainers don't interchange as the non common block retainers are made for a non recessed block with a different bolt pattern..
There were some factory replacement warranty common blocks that weren't recessed to fit older cars but they are very scarce. Not as scarce as 340, 4 bolt main station wagon blocks, but scarce.!!!
OK, so they don't interchange with the common block and earlier block. Good to know there is actually a slight difference. Thanks.