Hello all ,

I decided to finally start my LS swap thread.

I've owned my 86 IROC for three and a half years. It was kept in a barn and infested with mice when I bought it. Since then, I've stripped it down, put the rear end all back together, painted the interior metal, as well as the engine bay. I started out with the 305, but decided to discontinue it's use and go for an LS engine. I started out with a 4.8, but now I've decided to do the car justice and swap a 6.0 into it.

After dealing with buying a junk 6.0 with two blown up rods, the junk yard I got it from threw in an additional 6.0 short block for me to work with. Although the every bit of the interior of the motor is covered in thick brown sludge, most everything is reusable. I dropped it off disassembled at the local machine shop today, and they're going to get it all cleaned up and good to go. The owner of the shop told me that the sludge is most likely because of the early style heads being notorious for cracking near the bits of the center galley area. He said the steam passes through the PCV valve, but the glucose gets left behind, which makes the sludge. Not a problem since I'm using different heads, anyway. The piston ringlands are all still in good shape and the skirts look OK. They are going to check the bores and pistons for just a re-ring and hone.

The guy also mentioned that maybe I should consider using ARP main studs, because the GM bolts don't actually use all the threads in the block. He also recommends ARP hardware for the heads. Is it really worth spending that money on ARP hardware on a N/A engine that will most likely end up making 400 WHP or less?

Now the waiting begins, as the shop is one of the more well known ones in the area and they already have several other customers ahead of me. Time to focus on some smaller bits like porting and polishing my DBW TB.

Big plans for this car! I'll post bits as I get around to it

 

There is zero reason to not go with arp hardware. It's like saying "do I *need* insurance?" The added cost is just insurance.

 

You don't need ARP head studs. Here's what it comes down to for you: ARP head studs are reusable. Stock bolts are not. You'll have to buy new hardware no matter what, so look at the cost difference and decide whether it's worth it to you to be able to reuse the hardware. It's also very straight forward tightening ARP head studs. Just torque 'em up. Stock bolts are torque + angle so take into account buying tools to get the job done.

 

Yeah, I totally understand the idea of insuring my build. He recommended that if I want to, I could use ARP studs on the mains and use GM head bolts. The way he explained it is that ARP studs are most important on the mains, and that because the crank is always the fastest spinning part in the car, the extra hold down force of the ARP hardware is a good addition to the motor. I also learned that if I do choose to use ARP main hardware, I would likely have to get it align honed so I can use the next size up (OD) bearings, and that's because I guess the extra force of the studs can cause the normal size bearings to go out of perfect circle?

I do already have a full set of new GM head bolts in my garage, but I will think on it. I don't *think* that I will be taking it apart after I get it all together, but you never really know with a project car.

 

Now that couldn't possibly be more true. Even when "I'm going to do it right the first time" is your mentality

 

Everyone always wants a bit more than they already have!

I decided to call the machine shop up and request an align hone for the ARP main studs. Just ordered a set from Summit, and they are going to get that done for me!

Thanks for the input, guys. The ARP hardware will probably outlast the rest of the motor, lol!

 

If you don't have the coin for ARP hardware you can look into the Summit, Jegs, and Mr. Gasket hardware. I "think" they are also made by ARP. Very similar tool characteristics and doubt there is a stand alone supplier that can make these, at a smallish volume compared to ARP, with the same properties as ARP.

 

That's good to know. I don't mind getting ARP brand stuff, it will be worth the peace of mind. I also ordered ARP rod bolts, and the machine shop is going to get those done for me, too.

I also decided since I am getting everything else done, I'm not going to reuse pistons. The shop owner suggested a .020" over is a good size to go for, so I ordered a set of HD pistons through WS6 store, as they are supposed to be good quality replacements! I'm sticking with dish tops, because they are surfacing the block and the 243 heads, and 10.4-6:1 (somewhere in there) is a good dynamic compression number for my build.

 

Okay, I'm going to put on my flame suit and say this:

I know A LOT of guys who have reused those bolts with zero problems. Including experienced machinists; their advice is to not use the angle-method to tighten them, just use the maximum rated torque for a bolt that diameter.
Since there is no gasket to crush between the cap and the block, there is less chance of the bolt needing to "flex" to maintain integrity.
Also, these are cross-bolted caps; you've got the side bolts there for that (and other) reasons.

Option two is the made-in-China studs from Ebay for about $90. Lots of guys on LS1tech.com have used them, and I haven't heard of any failures in the years I've been frequenting that site.

Obviously, ARP is the best, but there are other options. Remember, you've got THIRTY bolts holding that crankshaft in place: Most Big Block Chevies back in the day only had TEN, and I've seen guys make some pretty serious power with two-bolt blocks.

How much power are you planning to make with this thing?

 

I do agree that there is nothing wrong with the stock bolts. They're quite hardy in comparison to the older style S/B-BC style bolts and caps. Basically, the owner of the shop said that Chevy is putting out thousands of motors a day, with a peak of near 250,000 SBC motors back in the day. He said that the blocks are machined and honed to GM spec, but these "specs" aren't perfect, which is why the LS motors have well known issues of things like cold piston slap. Not a huge deal, however, with ARP studs and an align hone, they can get it nearly perfect and you end up with a product that is even more reliable. This is my understanding of it. I have been going off what the shop has suggested and figuring it out as I go along.

I have already ordered the main studs from Summit. Alot of forum surfing I've done on LS1Tech and other sites suggest that it's a great idea to go with ARP stuff as you have the insurance and peace of mind. I wasn't aware cheaper stuff existed, mostly because every time I research this the result is always "ARP!!"

I honestly don't know what power I will end up making. However, I wasnt planning to go too big camshaft-wise. I was thinking maybe the CamMotion Titan 4 or maybe something *slightly* bigger. That's like 400-420 RWHP max, 460-500 BHP.

I hope that the shop isn't just trying to make extra cash off me.

 

I should also add that although they recommended all ARP hardware, he said by far the most important thing to upgrade was the connecting rod bolts. All other stuff is of less importance.

Its definitely not too late to return the main stud kit and just do the connecting rod upgrade.

Then perhaps I can use the money in other areas. From the research I've done tonight, stock caps and bolts are good to 750 BHP, most people just do it for extra strength/overkill.

 

Alright, I called the shop to get a definitive answer regarding ARP hardware on the bottom end. I explained that I was concerned it was a waste for my power level (~460-500 at the crank). They've built plenty of LS motors and do custom work with them often.

He said that if you're pinching for money, it's definitely an elective part. With FI it's a no brainer. With my power level, he said that it's still an elective part, but this is the power level that upgrades like these start to matter. He said that since I'm going with ARP hardware everywhere else, it's a good idea to stick with ARP bottom end stuff, as well.

Sorry about all the "he said," and whatnot. It's alot of money being thrown around, and I've been saving for it for a while. Just want to make sure I'm making good choices

 

i put a LQ9 6.0 in my camaro with a GM hot cam and ls1 intake everything else is stock, it's in the 400-450 range i would say. perfectly fine to use stock hardware.

just built a forged 2.3 4 cylinder for my mazdaspeed6 went with all ARP hardware. boost and while i'm there played a part

 

I've added up the total costs of this engine build, and I think I'm going to end up returning the main studs after all. Between the studs and line hone, that's $400 I can put elsewhere. I am also just going to use the new set of FelPro head bolts I have already, and not worry about head studs. I am definitely going to keep the ARP connecting rod bolts, though.

This went from a cheap-o 4.8 to a uh-oh all my project car money is gone 6.0 really quick

 

I'll never argue that upgrading rod bolts is a bad idea, but I'll say that once again it's optional DEPENDING ON YOUR REQUIREMENTS.

How high are you going to rev this thing? RPM kills rods/ rod bolts, not power output.

If you're not going over 7k, the general consensus is that stock will be fine, and lots of guys have reused them.

However, if you want ARP bolts in your factory rods, GET THEM RESIZED.

There are a lot of threads on LS1tech where guys "upgraded" to ARP rod bolts, and spun bearings. Different clamping loads and all that.

I know it sounds crazy, because cracked cap rods are supposed to eliminate any sort of misalignment issues, but there are too many people saying it was a problem to ignore.

 

You're absolutely right. I won't be revving it that high. The big reason I am going to get the rod bolts done is because it is cheap, and it is one part of the motor that is not as strong as the some of the other features that came on the LS motors. The machine shop promised that the rod resizing is cheap, and that it will be worth it.

 

cost of things is ridiculous.... it cost me ~$5k to build my 2.3 4 cylinder.

 

Wow, that's incredible! It must be one MEAN 2.3, though!

 

Does GM use ARP in the Camaro ZL1 motor???

 

No, they do not. However, the LSA ECM in stock form cuts off RPMs at 6200.

Like Dixie said, it's the RPM that kills parts, not the HP. I'll be running well over 6200 RPMs for sure

 

So, I had an idea. I know that using SBC headers as a starting point for LS headers is a lot of work. However, I had purchased a new set of Hedman Headers P/N 68481 for $300 about two years ago. I was planning on using them on my 305, but had ended up deciding to do the engine swap. They're "shorty" headers, although they seem to be actually closer in length to mids. I was thinking that I might be able to save these from going to waste and building my headers out of them, and still being able to use cats like I wanted to. 1-5/8" primaries, and 3" collectors. Here's a picture of these headers:


Obviously the y-pipe isn't going to work, and that's fine. I would just cut the flange off of it after the 90 deg. bend. I would weld some small cats to the 90 deg. bits and I was thinking that the cats should sit about where the collectors of the LS swap long tubes sit? I could get a cheap set of LS flanges off eBay, and then bend and cut the primaries into place. The AIR tubes would be cut off close to the primaries, pinched and then welded. I really love messing around with my welder, so I don't mind doing the work.

What do you guys think? A good option for some LS headers with cats, or a waste of time and money?

 

Reworked or not, do you want to have 1 5/8 primaries on a 6.0?

 

DONT REUSE OLD STOCK HEAD BOLTS! Tried to tune a 2004 Yukon Denali last year. First WOT pull, I heard what sounded like a header leak. It wasnt a header leak. It was the driver side head gasket. The mechanic reused the old stock head bolts. He wouldve been OK if he used NEW bolts. My G8 has had the heads off TWICE. First (2015) time was to delete the DOD crap. ARP head bolts went in. Second time (2018) was to was to replace cam and lifters (Soft cam core went flat and munched a lifter). Reused the head bolts. Now if youre planning on BOOST, I would consider ARP head studs. Now as far as the main suds go, nah... REALLY not needed. Unless youre shooting for way over 1000 HP, stock main and rods bolts will be OK. Richard Holdener made 1500 on a SBE (stock bottom end) with just added ring gap on the pistons.

This isnt a SBC. No need for upgraded main caps, splayed 4-bolt main caps setups (LS engines are SIX BOLT), overpriced studs, upgraded rod bolts or any of that fancy stuff. Hopefully you have 2005+ year engine with the better rods. I know folks that are BOOSTED and put down 800+ on the SBE. 500whp and under 7000rpm? That SBE can handle it just fine. My G8 makes way over 400+ NA, I twist it to 6800 and it has 190K miles on it. THE SHORT BLOCK HAS NEVER BEEN APART.

 

Most my driving will be on the street. So maybe 2000-5500 RPM. Might see drag strip once or twice.

Option 2 is the '02 LS manifolds I have, as well.

Which one would flow better on the 6.0?

 

Hello, thanks for the input. Yeah, I would never use stock used head bolts. Only new. I actually don't know for sure what year this 6.0 is. Apparently the early LS motors had some problematic rod bolts. So I'm just going to switch them out and feel better in the end.

 

2000-5500 RPM? Again, this is NOT an SBC, TPI, etc. My G8 has a Texas Speed LS3 NA Stage 1 cam (225/236 .629/.619 114 LSA +4) and easily runs to 6500 RPM. . 5500 RPM MAX? Leave the stock cam in. Like SERIOUSLY!

Why not get the Speed Engineering headers https://www.speed-engineering.com/ls...2-ls3-ls6.html

I woud run the LS manifolds way before I'd run those 1-5/8" crapola headers. Or you can spend some dough and run the Hooker Blackheart setup...

 

I like those, but I can't run Cat Converters on LTs with a 4l60e.

 

Well here's another Richard Holdener reference. Gen 3 LQ4 made 1300 hp. And the rods bolts arent a serious issue unless youre trying to spin to 7000+. I've powershifted LS1 Camaros with heads, cam and boltons at 6500 RPM and they held together. Becomes a serious issue if youre trying to spin it to.. again... 7000+ RPM.

BTW I come from the small-block world. That 5500rpm number is COMMON, especially amongst us 3rd gen fans. Heck... We learned that if your HP peak was at 6000rpm, your car wasnt a street car anymore. BOY WERE THEY WRONG. In an SBC, you will need valvetrain upgrades (rockers), a single plane or RPM Airgap (Or a MiniRam/LT1 style intake), etc. The FACTORY ROCKERS (with trunnion upgrades) and the factory truck intake (also the LS1/2/6 and TBSS) can work up to 6500 RPM.

Time to study these LS engines. I was sold when either Super Chevy or Car Craft (I cant remember) did their 402 LS to 406 SBC shootout. The LS made more HP with less cam and STOCK NON PORTED LS3 heads (I would put those on your 6.0). The SBC had AFTERMARKET HEADS. The LS cam was 10-15 degrees @.050 SMALLER than the SBC and still made more PEAK AND AVERAGE HP/TQ.

 

Absolutely you are right. I am more talking about the RPM range it would be realistically be used in. I am not planning to smash the pedal in traffic, that would just be silly. My max RPM will be 7k or under. But tests have shown that different diameter headers have different effects for different uses. 1-1/2" - 1-5/8" is actually the recommended size range for a small block motor on the street. From what I read, the scavenging of the smaller size promotes better low range torque. Large, long runners promote higher RPM power, which is why the HUGE gains you see are in the higher RPMs.

Also, I did a quick measurement on the LS 99-02 mannys. They are ovular tubes that measure 1-1/2" x 1-5/8" that run into a 2-1/2" collector. 1-5/8" mid length tubes would, theoretically, flow slightly better and be better for the higher RPMs in the 6.0. Just my speculations.

 

What are these cats you speak of? LOL!

Do you need cats for visual inspection? Do they do a snaff test on the car? Guess Im lucky im in Maryland. No emissions on 95 and older. Historic tags (20+ years old) or Street Rod tags (25+ years old and modified) make you inspection/emissions exempt also. Do yall have something like this in Oregon?

 

Oh, my. You've never experienced an engine like what you've built, have you? You're in for a surprise that's going to paste a grin from ear to ear.... and it's all yours, buddy. Enjoy!

Definitely open up ability for the engine to breath up top if you can. You'll see why the first time you stomp it.

 

No, sir. I am less than a mile from the county line that does require inspections. I would legally be fine without them. I just want to have a bit of control over the smells, especially since I have the t-top. Plus, it's not a bad idea to do my bit for the environment and all that.

 

I really haven't. I am super excited see what all the excitement is all about.

What do you think QwkTrip, would the Hedman headers be an upgrade over the manifolds?

I could also search around for some of the BBC headers offered for our cars. Something like these:

 

I don't know, I'm not well versed on the shorty and mid-length headers. Need to defer to other people.

Maybe cruise the Hawks website as they tend to have a decent variety of choices to view. Kooks and ARH (American Racing Headers) might make some mid-lengths for our cars. ARH is not known for being cheap though.

I kind of doubt the BBC pattern is close enough but you can look into that. Those big block headers shown have kind of a tri-Y which is dependent on firing order. Not sure if LS and BBC have the same firing order. All things that must be considered if you're going to avoid direct bolt-in.

 

If your tuner is worth his marbles, your car wont smell like raw fuel...

 

LMAO he might want to invest from some huggies! LOL! My G8 is a straight a-hole from 3000rpm up (cam sweet spot) and she weighs in at 3800+ pounds! That IROC will be a shock to his system. Better have the sanitation department on speed dial because there will be cleanup needed on isle 13! LOL!

 

Run the factory manifolds until youre "ready"... LOL

 

Ooooooh youre in for a TREAT. Ever drove a late L98 IROC or 91-92 L98 Z28? I drove a 92 NEW in 91 (hehe...). I was SHOCKED at the power. A cammed 6.0 LS with LS3 heads in the same weight car is... SCARY in the wrong hands. Even if its an LQ4 with only 9.5:1 compression...

 

I have not, lol. I am using 243 heads and an LS6 intake, so it should be real nice to drive.

 

Oh yeah. That will be REAL nice... It should make 400whp EASY. Maybe 420. You do know thats 500+ crank, right? Imagine... You used to have to build AT LEAST a high compression 355 or a 383 to get that with an SBC...

Stock PCM or Term X?

 

It's a stock PCM from an Escalade. 24x reluctor with the early style DBW pedal and throttle body. I will be trimming the DBW pedal down and I'll weld a third gen gas pedal on to that. Gets rid of the old vacuum cruise.

 

I will do further research before I make a further choice.

Kooks does make some LS mid tubes for third gens for around $900, and they are fancy. ARH does not.

Thanks for reminding me of the Tri-Y that conventional GM firing orders used. I guess LS motors switched over to a much more "balanced" firing order, so the side with the double y would actually hurt performance, I think.

 

BPR Hotrods makes a MidLength LS swap header for our cars. Not sure I've seen anyone use it. I am not sure what the benefits would be since you still have to fab up a Y-pipe and gain only a little ground clearance over regular longtubes.

 

Yeah, and they lack photos of both sides. I saw those, but not worth that. Yeah, I'm not looking for ground clearance over the LT headers, rather was just trying to get some cats put behind some mids. That way the 6.0 can breathe and I can still have relatively clean exhaust.

I've seen alot of different universal types, but i cant try them without buying them. I might be best off just getting one of the tube bend kits and making my own.

 

243 heads arrived, so I got them stripped down. As soon as the pistons from WS6Store arrive, I'll deliver all the new stuff to the machine shop.

Another idea for headers is I could maybe just buy the Speed Engineering or some other cheap headers, and cut back a bit before the collectors, and then merge them a bit sooner than they are in their current state. That might give me the room I would need to put some cats in.

 

This is my exhaust using 2002 4th gen manifolds. I needed to run cats because no one here will make a custom exhaust without them. Three inch the rest of the way back with a single in and out muffler. Stock LS3 with only about 200 miles on it at the time it was tuned made 368 hp at the wheels

 

Wow, I appreciate the information and photo! I see that the cats are actually pretty far back in the Y pipe assembly. You know, I think I might actually be able to just use the Speed Engineering headers, after all. Even if I just have to place the cats further back like yours, I think it should still work okay. They may not work at max efficiency, but they should filter out alot of the fuel smell!

 

Here's how I did it. Ask if you have any questions.

You don't need to weld anything on that gas pedal, just trim it properly.

 

This is super helpful! Thank you bunches.

I dropped off the pistons, rod bolts and heads to the machine shop. The owner walked me through the shop and it is chock full of engines needing work. Looks like I will have a couple months to work on other parts of my project.

I got a rotary kit for my cheapo tool and I'm going to port and polish the TB next weekend.

 

Two camshafts I have been considering are the CamMotion Titan 2 and the Titan 4. I really wanted the 4, because I think it has much better specs for the 6.0. Well, I didn't really like that it had over .600 lift, so I ended up doing more research and found that Jegs sells TFS cams under their name. I ended up purchasing their 228/230 .585/.585 112 cam. I got the cam and their .600 springs for $360. It should play very well with the rest of the setup.