I think this has been beat to death. I'll leave it with this everyone can make up their own mind .
Engine rebuild questions
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I agree with 440sixpack. If you are running 9.5 or higher compression on a street motor with iron heads you should run 92 or higher octane (or the equivalent in your area). Modern cars do run up to 12:1 compression and they are fine due to knock sensors and other sensor that can adjust timing on the go even per cylinder. If you run 87 you may not have any issues I agree, however you will need to retard timing which makes the higher compression somewhat a mute point to a degree (pun intended haha). It does not hurt anything to run higher octane but it will hurt things if you have too far advanced timing and not enough ignition on 87 octane (remember you also need a stronger spark with higher compression), not worth the risk. Higher compression helps torque and power with the right combo (camshaft, intake etc) only if you build it right.1983 Jeep Wagoneer-322,000 miles.
1972 Jeep Wagoneer-360-auto-sold
1988 Jeep Grand Wagoneer-One owner-64,000 original miles-Sold unfortunately
1968 Jeep Gladiator, full Resto in progress
1963 two door ifs one owner Wagoneer
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Different engines do tolerate more or less compression in stock form than other's. For example I run 9.8:1 compression on my 302 with heavily worked over factory 351 iron heads on 93 octane, mainly due to the way the combustion chamber is designed. I also have a pretty advanced timing curve, however I also run good aftermarket ignition components and have it tuned well, I am still careful of detonation though. There is no absolute rule for what all engines can run, it is dependent on design, tuning, building and etc.1983 Jeep Wagoneer-322,000 miles.
1972 Jeep Wagoneer-360-auto-sold
1988 Jeep Grand Wagoneer-One owner-64,000 original miles-Sold unfortunately
1968 Jeep Gladiator, full Resto in progress
1963 two door ifs one owner Wagoneer
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Chevy 454
I can?t run 87 octane in my Cherokee .9.8 to 1 . Pop up forged pistons.word products Merlin oval port heads 269 cc intake runners .big tube headers .gm performance intake.770 Holley .dui ignition .2 1/2 duel exhaust .hush power stainless mufflers. Nv4500 5 speed . 456 Detroit locker .just will not use 87 octane1982 cherokee nt. 454. nv4500 .205. dana 60 f+r. twin stick.hydroboost.hydrolic clutch.rock ram.traction bar.warn 12000 winch.4 wheel disc.flip kit.soa.high steer.cross over steer.4.56 detroit locker.35 spline rear alloy axles. 37s .1990 grand wagoneer aka trusty rusty
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