...how many cc's are the stock cast iron L98 heads...

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Feb 15, 2001 | 02:00 PM

jimbo

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Joined: Jul 1999

Posts: 202

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From: Melbourne Beach, Florida, USA

Car: 1991 Formula Firehawk (Clone)

Engine: 350 with Firehawk Package

Transmission: 700R4

...how many cc's are the stock cast iron L98 heads...

...on the 1991-1992 f-body 350, and what was the stock compression ratio? Also, isn't there a link on this board somewhere to the 3rd gen Camaro database...

...could swear I saw one here not too long ago...must be going blind...

TIA

Feb 15, 2001 | 02:17 PM

TransamGTA350

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From: South Windsor, CT

Car: '89 GTA

Engine: ZZ6TPI

Transmission: T56

Axle/Gears: Borg Warner 3.70:1

64cc

Feb 15, 2001 | 02:28 PM

2QUIK6

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Joined: Jan 2001

Posts: 436

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From: Ft. Worth, TX

Car: 89 Turbo Trans Am and lots of non-3rd gens

Engine: 231 SFI Turbo's, LT4, LT1

Transmission: 2004r, 4L60E

What is the compression ratio for a L98 engine with those 64cc heads on it?
Reason I ask is I was told the ZZ4 short block with the 64cc heads would be 9.5:1 requiring premium gas

------------------
Rob
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Feb 15, 2001 | 02:45 PM

Kevin91Z

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From: Orange, SoCal

Car: 1990 Pontiac Trans Am

Engine: 355 TPI siamesed runners

Transmission: Tremec T56

Axle/Gears: 12-Bolt 3.73

87-89 L98's are 9.3:1. 90-92 L98's are 9.7:1. I'm not 100% on this. You should be using premium fuel anyway. Or you can get by with 89 if you dont race and you arent getting any knock. Leave the timing in the stock setting or make it 4º if you're going to run less than 92 octane.

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1991 Camaro Z28
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Feb 15, 2001 | 03:28 PM

R.O.B.

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Joined: Aug 1999

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From: Glendale, AZ

I know that using the ZZ4 short block with Vette heads, 58cc, gives 10:1 compression. Using the Fastburn heads, 62cc, gives 9.6:1 compression. So with this being 1cc per point, I would guess that 64cc heads would give you 9.4:1 using the ZZ4 short block.

------------------
Rob
'86 TA 305 TPI
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Ported Plenum
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