Question on PRC stage 2.5 heads for 5.3
#1
TECH Enthusiast
Thread Starter
iTrader: (5)
Join Date: Jan 2009
Location: Huntsville, Tx
Posts: 505
Likes: 0
Received 0 Likes
on
0 Posts
Question on PRC stage 2.5 heads for 5.3
Eventually I am going to build a 5.3 to take the place of my 4.8. However instead of just rebuilding a regular 5.3, I wanted to use flat pistons from a 4.8 for higher compression. At first I would have stock heads, but eventually a set of the PRC's will be purchased.
My question is this: stock compression is 9.5:1 right? Flat-top pistons will raise it to 10:1 correct?
Finally Texas Speed says the heads are designed to raise compression to 10.75:1...with the flat tops this would raise it to over 11:1... can you run this with pump gas? If not, how would one go about lowering the compression while still using the flat tops?
OR is all my math wrong...help me
My question is this: stock compression is 9.5:1 right? Flat-top pistons will raise it to 10:1 correct?
Finally Texas Speed says the heads are designed to raise compression to 10.75:1...with the flat tops this would raise it to over 11:1... can you run this with pump gas? If not, how would one go about lowering the compression while still using the flat tops?
OR is all my math wrong...help me
#2
formerly ByuTrukFreak
Join Date: Mar 2006
Location: Golden Meadow,LA
Posts: 296
Likes: 0
Received 0 Likes
on
0 Posts
I'm sure you can run 11:1 with pump gas as long as you use 93. Thicker head gaskets will drop it some too, I think a lot of duration will bleed off some too
#3
TECH Junkie
iTrader: (18)
Eventually I am going to build a 5.3 to take the place of my 4.8. However instead of just rebuilding a regular 5.3, I wanted to use flat pistons from a 4.8 for higher compression. At first I would have stock heads, but eventually a set of the PRC's will be purchased.
My question is this: stock compression is 9.5:1 right? Flat-top pistons will raise it to 10:1 correct?
Finally Texas Speed says the heads are designed to raise compression to 10.75:1...with the flat tops this would raise it to over 11:1... can you run this with pump gas? If not, how would one go about lowering the compression while still using the flat tops?
OR is all my math wrong...help me
My question is this: stock compression is 9.5:1 right? Flat-top pistons will raise it to 10:1 correct?
Finally Texas Speed says the heads are designed to raise compression to 10.75:1...with the flat tops this would raise it to over 11:1... can you run this with pump gas? If not, how would one go about lowering the compression while still using the flat tops?
OR is all my math wrong...help me
11:1 or even 11:5 would be fine with pump gas ( 93 octane ) theres a few i know who runs 12:1 without issues on pump gas even 12:5
#7
TECH Resident
iTrader: (18)
Join Date: Mar 2005
Location: Hattiesburg, Mississippi
Posts: 772
Likes: 0
Received 0 Likes
on
0 Posts
4.8 pistons in a 5.3 with the stock MLS gasket and the stock 706/862 heads is almost right at 10.3:1 CR. If that helps ya...so if the PRCs are milled any then compression will go up from there... I have this same combo and am about to switch to 243's so i can go down to around 9.9:1 for FI
Trending Topics
Thread
Thread Starter
Forum
Replies
Last Post
5.3lSilverado
GM Engine & Exhaust Performance
25
08-29-2016 12:48 AM
KyleW707
GM Parts Classifieds
4
07-29-2015 08:17 AM