When going with a Griffin or other race type radiator I strongly recommend the 2" core, not any big thick thing especially for slow running.
With the thick core the air passing through warms as it passes the front of the core and by the time it is going through the back half of the radiator it no longer cools anything.
The 2" core is more than generous for what you need.
This is my 3.8L Gen 2
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And this is my turbo gen 1 twenty some odd years after building it.
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Cheers, Charlie
If It ain't broke, Modify it!
87 Montero turbo Converted back in Spring1989
95 Montero SR 3.8 DOHC Only one?
93 Pajero 3 door 6G75 Mivec with paddle shifted 5 speed
Then a Gen2 SR with full coil independent suspension.