Next, the valve springs were compressed so the keepers could be installed.Those Comp Cams Ti retainers look pretty trick!Our repaired heads are ready to go!After dropping in our new Comp Cams low lash lifters and screwing in the ARP studs, Howard installs one of the heads.Our new lifters are installed, and the ARP studs screwed in and tightened down before the other head is dropped in.With the heads torqued down, the front end accessories are reinstalled, the headers bolted back in and the FAST LSXR intake manifold is lowered in place and tightened.The old engine builder decided it was fine to just remove the factory steam bleed tubes and cap them off with bolts. This was one of the main reasons why Rathyna’s car was always prone to overheat. We installed a bleed crossover kit from Nitrous Outlet that came with quality AN lines and high flowing distribution blocks to positively get rid of all the air bubbles in the system.
Sure the LQ9 is a Gen III and the LS3 is a Gen IV but there are not many differences between the Gen III and Gen IV engines and most parts interchange. The major differences between engine generations here are some to accommodate DOD and VVT options that the LS3 does not use anyway. Where it affects you, in this case, is a single bolt vs 3 bolt cam for the sprocket. The LQ9 has a 4″ bore with the same stroke but its iron block can easily be bored to the LS3’s 4.065, all the internal parts interchange. The heads are the square port, LS3, L92 improved square port configuration and everything interchanges. A lot of Chevy tuners like the LQ9 for an inexpensive forced induction block as the iron block is stiffer under boost. Its cheaper than the LS7 based six head bolt solutions for better head sealing under pressure.
The Comp Cams Trunion has a lot more bearing area than stock. As you can see in this picture the size difference in bearing area between stock and Comp Cams. You can also see that the stock trunions were beginning to gall on this engine with a stock cam and valvetrain. Installation does require some finesse and proper use of a press. A lot of people have good luck with this kit and perhaps some of the early failures were perhaps caused by improper heat treating and installation.
I have seen many failures of stock rockers in high-level drifting which is more brutal than drag and road racing in some ways. Check out the pictures and the galling of the stock shafts.
Your info is good to know and thank you for bringing it to our attention and we will be keeping an eye on them but I don’t think we will have problems. We will report if we have issues.
You are completely right, our block is bored out quite a bit to 4.065 and you can go as much as 4.090 as I recall which you can’t do with the aluminum blocks. Everything does interchange between the two motors though.
I unfortunately wasn’t really raised or taught to maintain vehicles. I have always been a driver, and the circles I associated with growing up never emphasized car maintenance. It was all about driving. Luckily I found MotoIQ and they’re teaching me a different way – it’s kind of a running joke with me at this point. I’ve gotten better…not quite good at it yet, but I at least understand the importance of vehicle maintenance and safety now 🙂
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The LQ9 isn’t the iron block version of the LS3, they’re not even from the same LS Generation (LQ9 is Gen III and LS3 is Gen IV).
Sure the LQ9 is a Gen III and the LS3 is a Gen IV but there are not many differences between the Gen III and Gen IV engines and most parts interchange. The major differences between engine generations here are some to accommodate DOD and VVT options that the LS3 does not use anyway. Where it affects you, in this case, is a single bolt vs 3 bolt cam for the sprocket. The LQ9 has a 4″ bore with the same stroke but its iron block can easily be bored to the LS3’s 4.065, all the internal parts interchange. The heads are the square port, LS3, L92 improved square port configuration and everything interchanges. A lot of Chevy tuners like the LQ9 for an inexpensive forced induction block as the iron block is stiffer under boost. Its cheaper than the LS7 based six head bolt solutions for better head sealing under pressure.
I would highly avoid using the compcam trunion upgrades. They fail at an extreme rate.
Just check out some of these failures.
https://www.corvetteforum.com/forums/c6-tech-performance/3546465-fail-comp-cams-trunion-upgrade.html
I’ve read nothing but bad things. Ton of posts of exactly the same bearing failure. They just have a poor design.
The Comp Cams Trunion has a lot more bearing area than stock. As you can see in this picture the size difference in bearing area between stock and Comp Cams. You can also see that the stock trunions were beginning to gall on this engine with a stock cam and valvetrain. Installation does require some finesse and proper use of a press. A lot of people have good luck with this kit and perhaps some of the early failures were perhaps caused by improper heat treating and installation.
I have seen many failures of stock rockers in high-level drifting which is more brutal than drag and road racing in some ways. Check out the pictures and the galling of the stock shafts.
https://photos.smugmug.com/MotoIQ/Project-Cars/Project-Pink-350z/i-PKXPZXt/0/cf264521/L/DSC_0817-L.jpg
Your info is good to know and thank you for bringing it to our attention and we will be keeping an eye on them but I don’t think we will have problems. We will report if we have issues.
Lots of recent failures of the comp kits.
https://www.corvetteforum.com/forums/c6-corvette-zr1-and-z06/3802785-failed-comp-cams-trunions.html
I would not use them. Better alternative is either straub kit or CHE precision.
https://www.corvetteforum.com/forums/c5-tech/4130290-che-trunion-upgrade.html
LS3 is not the same bore as LQ9. 4.065 Bore vs 4.00
You are completely right, our block is bored out quite a bit to 4.065 and you can go as much as 4.090 as I recall which you can’t do with the aluminum blocks. Everything does interchange between the two motors though.
Due to Rathyna’s penchant for not maintaining anything,
Lol a woman not take care of her car?!!?!?! Unheard of!
Men can do this as well… Has nothing to do with sex.
I unfortunately wasn’t really raised or taught to maintain vehicles. I have always been a driver, and the circles I associated with growing up never emphasized car maintenance. It was all about driving. Luckily I found MotoIQ and they’re teaching me a different way – it’s kind of a running joke with me at this point. I’ve gotten better…not quite good at it yet, but I at least understand the importance of vehicle maintenance and safety now 🙂
TGI for MotoIQ <3