Max Compression on 89 Octane

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May 24, 2018 | 12:29 AM

DustyNova442

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Max Compression on 89 Octane

Im thinking of building a 434 ci lsx block for fun, Can i get away with 89 octane on 10:5:1 if it was tuned

May 24, 2018 | 12:34 AM

whatsa347

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From: clear lake, Texas

Sure.

May 24, 2018 | 09:16 AM

kinglt-1

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Should be able too...just have to set the spark tables up correctly.

May 24, 2018 | 07:19 PM

DustyNova442

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How high can you go on regular unleaded or mid grade

May 27, 2018 | 09:19 AM

8.Lug

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From: PNW

You’re not going past 10:1 on 87 if that’s what you’re asking. But even at 10:1, your PCM is going to detect too much knock in the higher RPM’s and revert your time table and cut a **** ton of power. It will be fine to daily but you’re not going anywhere with 87 as far as racing it.

May 27, 2018 | 09:33 AM

DustyNova442

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its going to be a daily driver the thing probably wont ever rev past 6k as its going in a 4x4

May 27, 2018 | 10:21 AM

8.Lug

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From: PNW

When I say higher revs I mean above what most any auto is going to shift at during daily driving. Figure anything below 3500 and you’re not going to notice anything. Jumping on the highway at full throttle - yeah, you’re gonna feel a power loss.