492 heads
07-07-2019, 12:37 PM
#1
492 heads
I found some 492 heads for sale locally. Will these be a direct swap onto my 1975 L48? Wil the EGR valve still work or are there no ports for that on these heads? These heads are bare castings so I'll need to get valves, rockers, and springs.. will the swap be worth the performance increase or is it minimal?
07-07-2019, 01:26 PM
#2
Melting Slicks
The double hump heads are very good. BUT it depends what you have to pay for those bare heads, Plus cleanup, crack checking, and parts to get the head ready for installation.
07-07-2019, 01:40 PM
#3
Le Mans Master
Member Since: Sep 2001
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492 Yes, direct swap. Yes, has exhaust riser. Yes, EGR ...
... But with purchase cost, then paying a shop to rebuild-assemble heads ... you may be close to better-performing heads' cost.
If I didn't require EGR ... they've become hard to find, but good used L98 aka ZZ4 heads ... aluminum w/ 58cc chambers.
If I didn't require EGR ... I'd also be looking for good used Vortecs iron 64cc & a cheap used intake.
EQ aka EngineQuest makes a very good & affordable "hybrid" iron head with heat riser & great Vortec fastburn 64cc chamber ...
... fits conventional intake ... pn CH350H bare or CH350HA assembled. CoO New Zealand.
... But with purchase cost, then paying a shop to rebuild-assemble heads ... you may be close to better-performing heads' cost.
If I didn't require EGR ... they've become hard to find, but good used L98 aka ZZ4 heads ... aluminum w/ 58cc chambers.
If I didn't require EGR ... I'd also be looking for good used Vortecs iron 64cc & a cheap used intake.
EQ aka EngineQuest makes a very good & affordable "hybrid" iron head with heat riser & great Vortec fastburn 64cc chamber ...
... fits conventional intake ... pn CH350H bare or CH350HA assembled. CoO New Zealand.
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Kacyc3 (07-08-2019)
07-07-2019, 04:17 PM
#4
Team Owner
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St. Jude Donor '05
not sure youll really feel a difference at least with what it will cost to go through them.
Even adding larger valves, car felt exactly the same (bowl blend also) Sold them immediately went aftermarket and never looked back
Even adding larger valves, car felt exactly the same (bowl blend also) Sold them immediately went aftermarket and never looked back
Last edited by cv67; 07-07-2019 at 04:18 PM.
07-07-2019, 11:33 PM
#6
Le Mans Master
Member Since: Sep 2001
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EQ CH350HA New assembled Pair Plus head bolts Plus rocker studs = $818 delivered
https://www.ebay.com/itm/Chevrolet-3...oAAOSw7ThUkH4f
https://www.aamidwest.com/engineques...chevrolet-350/
https://2u7bve3d8yjttiswb3gnx3uo-wpe...atalog-web.pdf
https://www.ebay.com/itm/Chevrolet-3...oAAOSw7ThUkH4f
https://www.aamidwest.com/engineques...chevrolet-350/
https://2u7bve3d8yjttiswb3gnx3uo-wpe...atalog-web.pdf