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Octane and power

Yup you live in California like me the gas here is shit they mix all kinds of additives to gas and we lose power and mileage . my 2001 likes the mid grade best , and then there are the winter and summer blends . plus we are paying almost $4.00 a gal.
 
When I rebuilt/modified my 88XJ 4.0L, @ about 384,000 miles, it was set-up as follows:
1. Static CR: 11.25:1 (measured)
2. A Comp.Cams regrind that gave a Dynamic CR of 8.8:1 to enable using 87 Octane gas.
3. Venolia flat-head forged pistons w/slip-fit Tru-Arc'd removal pins (i.e. no pressed-in pins).
4. Quenched Height about 0.040 inch.
5. SS Manley valves and ported heads.
6.Cloyes roller timing chain drive
7. Balanced engine.

My engine runs great and my 88XJ is now at about
500,000 miles.

Best regards,

CJR
 
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