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I was curious exactly what was different between the two engines, bottem end, head, and manifold choices. I was considering starting off with a 2.4 head and maybe mating it to a 2.2 block to save some cash (vs the 2.4 block). If I were to 'build up' the engine at a later time what would i better off with? Are the case and oil galleys similar between the 2.2 and 2.4? And if i were to look for some more displacment and or turbocharge it, which would i be better off with. I cant afford FI to start off with. I dont have a problem with running dual webbers or a holley. Any ideas? Thanks again.
 

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Stick with the 2.2 head. It has the exact same sized valves as a 2.4 head, and the ports are nearly identical. Plus, the exhaust ports are a bit smaller and it produces better torque on sub-2.4 litre engines. Plus a 2.4 head costs a ton more....

2.2 blocks have some shortcomings though. The rods are the same crappy cast steel rods that are used on '74-'75 1.9 blocks and all the 2.0 blocks. Plus 2.2 pistons tend to collapse at the skirts. On the plus side, the crank is very strong yet lighter than a 1.9's at around 34 lbs. And early Opel 1.9 forged rods are a direct drop in. So with forged pistons and early rods the shortblock is VERY strong.

The 2.4 block is a good street block. It has a forged steel fully counterweighted crank, albeit heavy at 43 lbs. It has forged connecting rods that are slightly longer than a 1.9/2.0/2.2's, and nice quality Mahle pistons with fully floating pins. This block is pretty strong too, but I wouldn't rev it much past 7000 rpms without stronger rod bolts. Piston speeds are much higher due to the longer stroke.

Personally, I'd build up the 2.2 block if i were to turbo anything, at least for the money you want to spend.

For exhaust manifolds, any CIH exhaust manifold will bolt to any of the CIH heads. For intake manifolds, you will have to either use the OEM Opel 2.2 FI intake manifold (flows crappy though), or cut and weld a stock carbureted intake manifold to fit, or make a manifold from scratch.

Bob
 

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Ok if you used a 2.2 with early rods and better pistons. Turbocharged and intercooled it to around 12 pounds where do you think the power would be with a cleaned up intake? or go custom intake? There is a reason I ask
 

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nobody said:
Ok if you used a 2.2 with early rods and better pistons. Turbocharged and intercooled it to around 12 pounds where do you think the power would be with a cleaned up intake? or go custom intake? There is a reason I ask
Ultimately it boils down to the airflow potential of the turbo and the intercooler. A typical OEM passenger car T3 maxes out around 220 or so hp at 17-18 psi, but there are larger T3-based turbos from Grand Nationals or 2.3 Thunderbirds which are capable of more.

I've been looking into hybrid T3/T04E turbos to feed a 500+ hp project and the difference in the AR ratios and trim sizes is drastic compared to the smaller T3's.
 

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kmon said:
I was curious exactly what was different between the two engines, bottem end, head, and manifold choices. I was considering starting off with a 2.4 head and maybe mating it to a 2.2 block to save some cash (vs the 2.4 block). If I were to 'build up' the engine at a later time what would i better off with? Are the case and oil galleys similar between the 2.2 and 2.4? And if i were to look for some more displacment and or turbocharge it, which would i be better off with. I cant afford FI to start off with. I dont have a problem with running dual webbers or a holley. Any ideas? Thanks again.
I like the 2.4 components because:
- rods are steel with bronze bushing (22mm ready for forged pistons),
- crank is steel with 8 counterweights (very good balancing),
- stock head flows decently without extensive porting work (nice for beguiners like me!)
On the other hand:
- it's a PITA getting a nice CR (pistons have a big 12cc dish...)
- it's a PITA machining the crank to get it below ca. 16kg
- rod ratio is quite low, so requires to be cautious at high rpm
Of course price is also an issue but...
HTH,
Hiro
 
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