Like the title says, this is my first LS build and I’m looking for a couple suggestions and any tips if I’m missing something. The engine short block is a 24x LS2 from an '05 GTO with around 75k miles that I got from another member after it spun a rod bearing. I’ll be taking it to the machine shop in the next week or two and am hoping I can get away with a regrind/polish on the crank and re-use the stock bottom end with a fresh set of bearings. If it needs more than that I’m willing to spend what it takes to get it up and running, I just don’t want to blow too much of my limited budget if I don’t need to. The engine will be going in my ’84 K5 Blazer that will mainly be a fun cruiser/daily driver in the summer and a camping/hunting rig in the fall. Here’s what I’m planning so far:

Short Block: Hopefully stock bottom end (already has ARP main studs and rod bolts). If the machine shop says the cylinders need to be cleaned up/honed out, are there any budget friendly 4.005” pistons out there? I’ve found some JE (311956), Wiseco (AW-06980), and Mahle (LS1340005F04) forged piston kits that all seem to be made for the stock rods but they’re all in the $640-700 range. I don’t plan on going FI or ever spraying the motor though so if there’s a cheaper HE alternative out there I’d rather go that route but I’m only finding stuff in the 4.020” and up sizes…

Heads: Used 243 heads off CL (I’m thinking from a truck). The local machine shops wanted a lot more than I was thinking for a cleanup mill and valve job so I decided to send them to AI for their 226cc package with BTR .660” springs & titanium retainers. Going to try to keep the milling to a minimum since the stock 10.9:1 CR is already higher than what I’m used to and we only have 91 octane premium out here in CA. Hopefully I’ll have them back in 3 weeks.

Head Gaskets: I want to stick with GM MLS gaskets and was going to just go with the LS2 replacements (12589227) but I hear a ton of people using the LS9 gaskets (12622033) even though the bore size is 4.10”. I know the LS9 gaskets have more layers (which is supposed to be better?) but will the extra bore diameter be bad for the aluminum block or not really make a difference at all?

Intake: Stock TBSS/Gen IV truck intake and 87mm TB with 36# flex fuel injectors.

Exhaust: Plan on running 1-7/8” long tubes but not sure what after that. I’m thinking a dual 2.5” with an H or X pipe shouldn’t be too hard for an exhaust shop to fit around all the extra 4x4 stuff and should be fine for my setup but feel free to throw out suggestions if something would work better.

Cam Shaft: Looking for some suggestions on this one. Keep in mind this engine is going in a heavy truck that will need more torque down low where I’ll be using it than it will max rpm HP… I had been trying to get ahold of Martin at SRD for a while and decided to talk to a couple of other sponsor’s while I was waiting to hear back. Steven at Cam Motion recommended their LS2 Stage 1 cam 212/216 .552/.535 110 ICL 115 LSA. Jared with BTR recommended a custom 221/228 .609/.571 112+2 cam. And when Martin eventually got back to me he recommended a custom 226/230 .612/.595 112+2 cam paired with a 3000-3200 stall. Everything I’ve been reading in the forums would make me think that the smaller cam would be best for torque and keeping the power band down low where I’ll be using it but Martin says that custom grind with the recommended stall will be very torquey from 2000-4500 rpm and pull hard all the way to 6500 rpm. I’ve never seen anyone unhappy with one of Martin’s cams so I’m tempted to ignore what I’ve been reading on the forums and go with what he’s recommending

Lifters: This is another one I’m looking for suggestions on. I’m tempted to just run the Delphi/LS7 replacement lifters from one of the sponsors since I won’t be doing anything too crazy with this setup. With that said, I see a ton of people recommend the Morel 5315’s because there have been a few issues with the LS7 replacements and the Morels are supposed to be far superior. I think the only people who were having issues with the LS7 replacements were doing a lot more with their engines (more hp & rpms) than I ever will though so I don’t know if it’s really necessary or not.

Timing Set: Cloyes LS2 replacement (C3220)

Oil Pump: Haven’t ordered one yet because I’m still on the fence with whether I should just grab a Melling 10295 high pressure pump or go with a ported GM pump from TSP, Hubbard Racing, or SLP since they’re all close in price and have a ton members running either. I also saw the blueprinted Melling 10295’s from Precision Oil Pumps that look pretty sweet and don’t cost that much more than the other options I’ve been looking at.

Transmission/Transfer Case: Rebuilt junk yard 4L80E from an ’01 Silverado 2500 and a rebuilt NP241C from a ’90 Suburban 2500 (VSS) with a slip yoke eliminator

Torque Converter: Since I’m getting the trans rebuilt anyways, I definitely want to get a new TC that’s a little smaller and lighter than the factory one. Something like the 9.5” Vigilante from Precision Industries, 9.5” SS from Yank, or maybe a Pro II from Circle D but I'm not sure about the stall speed yet. I want to keep it somewhat small since it’s already a heavy truck but I was planning on waiting until I had the cam picked out and then talking to

Axles & Tires: The front axle is a 6 lug 10 Bolt with 3.73’s and a Hummer H3 brake upgrade. The rear is a 6 lug 9.5” SF 14 bolt with matching 3.73’s, an Eaton True Trac, and NBS disc brakes. Tires are 275/70R18’s (basically 33’s) but I might be going up to 35’s and 4.56 gears in a couple years when I get around to lifting the truck.

 

everything you just wrote is junk....u need to start over.....jk lol. sounds like you got it all under control. cant wait to see the finished product man!

 

Thanks, this project has been starting and stopping for around 2 years now so I've got almost everything figured out. Just a few things that I'm still fuzzy on like the cam, stall, oil pump, and head gaskets that I'm trying to dial in before it goes to the machine shop.

 

right on. im actually looking at the gm ported oil pump from tsp as well.

 

I use the LS9 gaskets. I also use the LS7 lifters without issues. Some people don't like them, but I have had good luck. I strongly suggest the trunion upgrade. When you are going with a higher lift, higher RPM's, stronger springs, it adds stress to the rocker. If the needle bearings come out, it will make a mess. It's cheap insurance when you have it apart.

 

Thanks that's a good point. I forgot to put in there that I plan on using the Straub trunnion upgrade kit. The last thing I would want is for the needle bearings to wreck my new/rebuilt engine...

 

I like the cam that Martin has speced for you as long as you run it with atleast a 3200 stall. get a good trans cooler and it will be fine.
mine stalls around 4000 and the hottest I seen was 195 on a 40c day in stop and go. normally stays around 180.
ls9 gaskets will be fine.
ls7 lifters will be fine.
I have ran a melling 295 before in a old 6l build and it worked great.
if you do plan to go up to 35"s I suggest going with 4.88s or 5.13 gears

 

I think martin's cam is a tad big for what you want to be honest.