Hi, building an LM7 engine. Basically turning it into a iron 346ci. Just wanted to see if what I have in mind will work and if I can get some recommendations or pointers for it. Not looking for huge power since this won't be a race car or anything mostly show/cruiser and something that sounds good. Engine will be going in a 92 Nissan 240sx. Car has some weight reduction done to it with Carbon Fiber parts and some of the stock sheet metal removed from certain areas of the car.

Block:
-LM7 bored out to 3.903
-Wiseco K398X3903 pistons (1.304" PCH, -3.2cc)
-Scat 2-ICR6125-7/16 (26125716) Rods (6.125" length)
-ARP bolts pretty much all around the block
-Stock 5.3L crank (3.622" stroke)

Heads:
-853 heads ported/polished and mill to 64cc
-Stock rockers with Comp Cam Trunnion kit
-I already have some Del West Titanium valves (2" Intake and 1.5" exhaust) that I was going to use for a RPM build but that build did not go through. Not sure if it will be worth using with this build.
-LS7 lifters and lifter trays
-Texas Speed 7.400" pushrods (already have)
-TSP MS4 or BTR Stage 4 cam (not sure if this will work for me)
-BTR .660" dual spring kit with Titanium retainers
-Cometic Headgasket .051" thickness (C5475-051)

Intake:
-Fast 92mm (would a TPIS LS6 intake be better for this setup?)
-Fast 92mm TB
-Fast Billet rails
-Fast Fuel Lines

Oil/Water pump and chain:
-Melling high volume (10296)
-Summit LS2 Timing Chain
-PRW High Flow water pump (1434620)

Headers:
-Hooker S13 headers (1-7/8 primary with 3" collector - mild steel, ceramic coated)


Not sure what size injectors to run? Any input is appreciated.

 

I bet it's gonna rip pretty good in a lightweight car like that. I'd throw some 42 lb injectors in there, so you'll have a little room to grow in case you want to later on

 

Thanks man. I hope it will rip when I needs to haha. Any recommendation on which brand of 42lb injectors?

 

I would just get some take-off LS3 injectors.

 

Awesome. Thanks! Just saw that they around that 42lb size so that definitely will work.

 

What is the performance goal? Seems like way too much work and money for the stated purpose.

 

No real performance goal. Just something that I want. I had an RPM build in mind but that was scrapped due to an issues I had with the crankshaft builder. Also had a Lunati 383 build in mind but the Iron 346ci is cheaper than the 383.

I do 95% of the work on my car.

 

Looks like a good parts list. I have the same rods and pistons, except for a 4.030" bore. The scat rods are really nice for the money, but the pin bores usually need a little attention. There's no chamfer around the pin bore so any nick or burr will keep the pin from going through. If you force it, it will just scratch the pin. I just used a large 1" diameter countersink bit and chamfered the bore. The pin bore is also a little tight for my liking. I was seeing .0006" clearance, which is what the stock engines usually have, but I like about .001" so I bumped them in the hone. All in all, roughly 30 minutes to make them perfect.

 

Thank you for that info. I was a bit worried about the Scat rods but I have, mostly, read good things about Scat so I decided to go with them. Plus, I have found them for around $325-$330 shipped. Which is always a plus.