LB7: My LB7 twin turbo engine build

SilveradoTwins02

Hopefully twins soon
Aug 5, 2014
194
0
0
Hanover PA
So. I know there has been a lot of these threads on here but I want to share mine also. So the motor has been pulled and I have rebuilding both front and rear suspensions and brakes. Now the motor work will start. Thanks to a lot of info on this site and talking to people that have built trucks I think I have an idea what direction I am going in. So my first thing was to De -lip the stock LB7 pistons. That is now done and working on keying the crank,cam and oil pump. Water pump is already welded. Here are the pistons
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GMCSLEHD

New member
Oct 13, 2006
10
0
1
Cool.

Did you de-lip the pistons yourself on a lathe or milling machine, or have it done?

ETA: Thanks for the info, and great pics! Keep us up to date. :thumb:

-Josh:)
 
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SilveradoTwins02

Hopefully twins soon
Aug 5, 2014
194
0
0
Hanover PA
I did it myself on my lathe. I have a jet 1440 big bore lathe and a mill too. I have keyed the cam and Saturday I made a jig to hold the crank and keyed that also. I talked to guy a while back and he told me to go 2.500 ID and a.1875 radius on the edge, it just smoothed them out with scotch brite when done.. I will post pics of the crank and cam. Just need to do the oil pump now.
 

Mile_high

The Mad Hatter
Oct 31, 2009
702
1
18
Denver, Colorado
I did it myself on my lathe. I have a jet 1440 big bore lathe and a mill too. I have keyed the cam and Saturday I made a jig to hold the crank and keyed that also. I talked to guy a while back and he told me to go 2.500 ID and a.1875 radius on the edge, it just smoothed them out with scotch brite when done.. I will post pics of the crank and cam. Just need to do the oil pump now.


3/16" or 1/8"? I've been told both. The .1875 you said is 3/16".
 

SilveradoTwins02

Hopefully twins soon
Aug 5, 2014
194
0
0
Hanover PA
Here are pics of the cam and crank. That crank is head as ???? I used a cobalt 5 mm end mill and went slow. Cam wasn't too bad. Used a 5 mm pin 2" long and inserted in the alignment holes. Then used a last word indicator in the quill of the mill and went up and down until perfectly straight to get the rotational alignment. The time was really in making the fixture to hold the crank. The cam I just used a large set of machine v blocks that I had.
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SilveradoTwins02

Hopefully twins soon
Aug 5, 2014
194
0
0
Hanover PA
Well spent a little time in the garage on Friday and was able to complete the machining if the oil pump shaft and gear to accept a 5/32 hardened pin.
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SilveradoTwins02

Hopefully twins soon
Aug 5, 2014
194
0
0
Hanover PA
Well after the last 3weeks or so, I finally think I have made my choices on what I am going to do for this build, parts wise. I am going with Carrillo rods, Mahle ring set and an ATI damper. Have it balanced along with my stock LB7pistons that I De lipped. Take my block down to my machine shop and have him clean it, replace the cam bearings and hone it.
Install the ARP main studs and he will align hone it too. I am sending my stock cam that I keyed out to have a regrind done to custom spec. I will be getting +1mm over SS intake and Inconel exhaust valves from REV. They will also be supplying my springs and retainers.
These parts are going to a shop with the heads where they will be installed after they run their CNC port program on them. Also having screw in cups installed. Will be running Max Spool pushers on this build. Only thing left are the injectors, 45 or 60 overs....

Parts
ARP main,head,rocker studs
ATI damper
Carrillo rods
Clevite H bearings
Mahle rings
Custom cam grind
REV +1mm over valves int. exh.
REV dual springs ,retainers
Max spool pushers 7/16x.195 wall
Screw in cups. Thanks to Scott !!
CNC ported heads.
45or60over injectors
LBZ pump

This should be a good foundation for an 800 or 850 hp build.
 

SilveradoTwins02

Hopefully twins soon
Aug 5, 2014
194
0
0
Hanover PA
I'd go at least 60 if not 100's. Wish I did bigger valves on mine, but I didn't have the 8k to spend

I found a great supplier for the valves. Very reasonable!! This brand of valves are actually being used by Wagler in the heads he produces. They are worth 20 and 28 CFM over the stock valves by looking at the flow sheet that my head porter provided. I will have a little over 3200 in the heads not 8k.

You have one hell of a build on ur motor. U should run great with that set up.
 

coreykav

New member
Sep 10, 2014
11
0
0
I'm keying my crank as well. But not sure if I should use a hard keyway or soft. What's your opinion