LS7 Piston Compatibility
10-07-2013, 09:38 AM
#1
Teching In
Thread Starter
iTrader: (1)
Join Date: May 2012
Posts: 6
Likes: 0
Received 0 Likes
on
0 Posts
LS7 Piston Compatibility Hello -
I'm in the process of building a LS7 engine from a new bare block. I am using stock crank/rods and have a question concerning the compatibility of some Diamond Pistons.
They are part number 55398 (no longer listed on their website).
Specs:
Bore: 4.155
Comp Height: 1.170
Volume -3.84cc
Lock Ring Part #: 01-5111
Wrist Pin Diameter: .925
Wrist Pin Lenght: 2.250
Calculating deck height (4/2)+6.077+1.17 = 9.247.
Will these pistons work using the stock rods/crank? I know the deck height is 9.25, but was hoping some of you guys could confirm the compatibility before I spend any money. I may have answered my own question but I come from the rotary world so I figured you all would be a bit more knowledgable.
Thanks for your help in advance!
I'm in the process of building a LS7 engine from a new bare block. I am using stock crank/rods and have a question concerning the compatibility of some Diamond Pistons.
They are part number 55398 (no longer listed on their website).
Specs:
Bore: 4.155
Comp Height: 1.170
Volume -3.84cc
Lock Ring Part #: 01-5111
Wrist Pin Diameter: .925
Wrist Pin Lenght: 2.250
Calculating deck height (4/2)+6.077+1.17 = 9.247.
Will these pistons work using the stock rods/crank? I know the deck height is 9.25, but was hoping some of you guys could confirm the compatibility before I spend any money. I may have answered my own question but I come from the rotary world so I figured you all would be a bit more knowledgable.
Thanks for your help in advance!
10-07-2013, 10:44 AM
#2
Are you going to be resleeving the block? That is too much bore for a stock LS7 cylinder sleeve.
__________________
Largest Stocking Distributor of LS-x Engines / CHECK OUT OUR NEW WEBSITE!
COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - KOOK'S HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - AND MORE!
Largest Stocking Distributor of LS-x Engines / CHECK OUT OUR NEW WEBSITE!
COMP - FAST - PACESETTER - DIAMOND RACING - EAGLE SPECIALTY PRODUCTS - CALLIES - COMETIC GASKETS
RAM CLUTCHES - MOSER ENGINEERING - KOOK'S HEADERS - ARP - GM BOLTS AND GASKETS - MSD - NGK
POWERBOND - ASP - AND MORE!
10-07-2013, 08:15 PM
#5
I'm also building an LS7 for my 69 Camaro from new and take out parts.
I bought a set of the Mahle ls7181125f03. These are flat tops with -3 CC valve reliefs and make 11.3ish compression with stock gaskets and 70 cc heads.
The LS7 stock rod is 6.067 CC and with the 1.81CH of the Mahles puts the piston .008 positive deck with the stock 9.240 deck height.
The Mahles are a 4032 alloy instead of the 2618 of most other aftermarket pistons, but in my opinion, for street motor, the tighter clearance and wear resistance of the 4032 is a plus. The pistons with pins and excellent ring pack (.043 top 1.5mm napier second) were less than $500.
I bought a set of the Mahle ls7181125f03. These are flat tops with -3 CC valve reliefs and make 11.3ish compression with stock gaskets and 70 cc heads.
The LS7 stock rod is 6.067 CC and with the 1.81CH of the Mahles puts the piston .008 positive deck with the stock 9.240 deck height.
The Mahles are a 4032 alloy instead of the 2618 of most other aftermarket pistons, but in my opinion, for street motor, the tighter clearance and wear resistance of the 4032 is a plus. The pistons with pins and excellent ring pack (.043 top 1.5mm napier second) were less than $500.
