XM262H with Stock 5.7L?
#1
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Joined: Mar 2012
Posts: 2
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From: Las Vegas, NV
Im just looking to do a minor performance upgrade to my boat. I did the 4 barrel conversion and put on an Edelbrock Performer with Edelbrock 1409 carb. Im wondering if I can get away with keeping the stock heads and putting in an XM262H cam without messing with the heads and exhaust system.
Just looking to get this thing to 275HP-300HP without spending the money on heads if at all possible.
If Im dreaming..dont be afraid to tell me so.
-Geoff
Just looking to get this thing to 275HP-300HP without spending the money on heads if at all possible.
If Im dreaming..dont be afraid to tell me so.
-Geoff
#2
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Joined: Feb 2007
Posts: 161
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From: Sweden
I think you will loose too much compression pressure if you have 76 cc heads.
Mid-range performance will suffer.
A pair of 64 cc Vortec heads will do the opposite, i.e. give you a nice midrange and a bump in peak hp's.
Mid-range performance will suffer.
A pair of 64 cc Vortec heads will do the opposite, i.e. give you a nice midrange and a bump in peak hp's.
#3
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Joined: Oct 2005
Posts: 1,074
Likes: 251
From: Waldorf, Md
Geoff,
You will have to change valve springs for sure. The Comp 981's may or may not be a direct drop in depending on the configuration of your factory heads in regards to rotators and stock spring heights.
I personally think you will see a lot more gain by upgrading the exhaust.
Bill Koustenis
Advanced Automotive Machine
Waldorf Md
You will have to change valve springs for sure. The Comp 981's may or may not be a direct drop in depending on the configuration of your factory heads in regards to rotators and stock spring heights.
I personally think you will see a lot more gain by upgrading the exhaust.
Bill Koustenis
Advanced Automotive Machine
Waldorf Md



