It could be a number of things. Are you sure it isn't just the normal LS sewing machine sound? Could be as simple as an exhaust leak. Or a bent push rod perhaps? Even an oil pump issue.
I think it may just be the lighting in the video. The block had just come back from the machine shop. If I recall correctly, some brands like Cometic specify a specific surface finish to use with their head gaskets, so you may need to make your machine shop aware of that. I was using the GM MLS head gaskets and did not have any issues with them. For my needs, they worked great.
It depends on the type of head bolts you are using. The stock head bolts are torque to yield, so they would follow and torque sequence you referenced. I am using ARP head bolts which are not TTY, which also makes them reusable which is nice. ARP provides the torque sequence and specs for when using their bolts.
The OE head bolts are torque-to-yield, thus the torque specs given in degrees. I used ARP head bolts which are not TTY, and thus use a specific torque value. You should follow the torque sequence for whichever type head bolts you are using.
My head gaskets aren't seating right. They seem to be a couple maybe 3 to 4 centimeters off? Any help here or is that okay? Also on my engine if the label front on the gasket would be upside down, is that ok or do I turn it over?
No, as long as the block and the cylinder head are clean and flat, there is typically no need for anything additional when using a MLS head gasket. Some people like to use a copper spray, and if you are reusing a head gasket, then that might offer some benefit. But the GM MLS gaskets are inexpensive, so I personally wouldn't bother reusing a gasket.
Did those heads require any further machining, or were they ready to go straight out of the box? I'm looking to upgrade the heads on my 5th gen Camaro LS3. Some people say not to install them straight out of the box, but rather take them to a machine shop to check all the clearances and such. Just wondering if I could get your take on that. Thanks for the videos! Its a pleasure to watch you work.
While it certainly couldn't hurt to have new heads double checked by another machine shop, in my opinion, it's not really needed if you're buying heads from a reputable place. Mine came from Texas Speed and were setup and ready to roll right out of the box. When I ordered them, I also had them mill the heads a bit to bump the compression up. No extra charge for that.
Cool, I'm about to do the same H/C install on my C5 when snow stops falling. What year is your C5? The steam tube plugs are a detail I haven't come across yet and I'd like to know if it's something I need to address. I also have the PRC 799 heads waiting to be installed , and my C5 is a 2002 with the LS6 intake. I know the steam tube routing is different on earlier LS1's. Thanks!
Great question! The steam vents are a hotly (no pun intended) debated subject, but I'll offer my opinion as someone who had the #7 piston fail. I've been recording video clips and will eventually post a video on how I am addressing the steam vents. The early LS1's had steam vents on all 4 corners. Starting in 2001, the LS1's actually got the LS6 intake manifold, and because of clearance issues under the intake, GM did away with the rear steam ports. My old 241 heads just had bolt on plugs/caps. The PRC heads I got actually had plugs pressed into the heads that had to be knocked out. There are several companies that sell steam vent tubing kits, but tend to be a little pricey ($140+). I'm using the GM truck rear cross over (GM # 12605716 - $35), and will route a hose forward and T into the front steam vent line.
So are you saying that running steam vents from all 4 corners is a safety/precautionary measure to hopefully avoid piston failure again? From my limited amount of googling this morning it looks like the steam vents let air escape out of the top of the cooling system so air bubbles and hot spots don't form. If you're going to go into what the system actually does and why you're running vents at all four corners in the next video I'll look out for it. Thanks again!
Yes. There are a lot of opinions about why the #7 cylinder is a common failure point, but I suspect it is related to excess heat/hot spots in that cylinder. In my humble opinion, opening up the rear steam ports is cheap/easy insurance and it certainly won't hurt anything.
Jason B thanks man I really appreciate the support. To me, looking at the bench flow numbers, it didn’t seem like the 2.5 heads were that significantly better than the 1.0 heads. Plus I was already at the limit of my budget. So I’m not saying the 2.5 heads aren’t better but there is a point of diminishing returns. But overall I’m very happy with the heads. No complaints and they made good power.
I bought mine through Texas Speed, it's their PRC brand. They do the CNC porting and setup the valves/springs. They'll also mill the heads if you want at no additional cost. I had them mill the heads down to 60cc, which should put me at around 11:1 compression.
thank you for the info! Did you have to buy the heads separately and then send them for porting? Keep up the good work, I look forward to every new video.
They offer both. If you already have 243 heads, you can send them in for porting. Or you can buy the 243 heads from them already ported, which is the route I went. I figured by the time I sourced 243 heads locally and then shipped them in, the cost wasn't much different vs buying directly from them. Plus you don't run the risk of getting a damaged head from Craigslist. The heads they have, they have already inspected, etc. The CNC porting on them looked excellent. No complaints at all.
Thanks. I can't wait to hear it run too. The motor is back in the car but I've had some fitment issues with the new headers, so that's been a set back. One day it will run again...
I agree. I personally have watched numerous other videos on LS engine building. Each person provides a slightly different method and perspective, and I learn something new every time. It's really too bad RU-vid is kicking small channels out of the RU-vid Partner Program. I suspect fewer and fewer people will create niche content like ours in the future.
FYI, you might have known what you are talking about if it werent for the fact that the torque value was only 25' pounds on what looks to be a 1/2 inch drive 8" - 10" long extension. Add in the fact that you dont know the quality or materials make up of the tools being used, the amount of twist deflection rating of said tools. Only when you change the centerline of the fasther being torqued relative to the centerline of the torque wrench head do you change the amount of torque being applied. An extension does not change the torque rating. The only times the torque is increased or decreased is if you lenghten or shorten the handle of the torque wrench, change the angle of eihter or both of the wrench or drive its self, the use of an offset tool such ad a crowsfoot, swivel or equivelent tool. Any time you change the An extension does not change the torque value much because of extension shaft twist and is pretty much eliminated if yu use impact extensions or an extension the next size up (depending on torque value specification) say 1/4 - 3/8 - 1/2 - 3/4 - 1 inch etc...
It's important to understand the difference between the stock head bolts, which are torque to yield (TTY) and aftermarket ARP head bolts. The factory TTY bolts use bolt stretch to set the clamping load, rather than a specific torque value. When you rotate the bolt 90 degrees and then another 70 degrees, you are significantly increasing the torque well beyond the original 22 ft lbs (you are actually stretching the bolt, putting it into yield; which is why they can't be used again). I am using the ARP bolts which are reusable and are set to a specific torque value published by ARP. cdn2.arp-bolts.com/instructions/134-3609_flat-washer.pdf
