Oversized INA lifters in 8v motor install
Posted: Tue Jan 18, 2022 8:21 pm
Hey Car pokes,
Saw some members were interested in replacing their original lifters and thought I would share some of the work I had done. I initially began this endeavor after I had discovered deep scratches in one of my lifter bores when replacing my head gasket. I briefly considered having the damaged bore welded then re-bored to original spec but was told by multiple professionals that welding a bearing surface was a bad idea. This is when I contacted the machinist that had rebuilt my cylinder head. He is a 944 savant and a true car guy. When I first visited his shop he had dozens of 944 cylinder heads and a few blocks that he was working on, needless to say, I trust the man's judgment. He suggested performing a modification were he would expand the lifter bores from 1.496 to 1.575 inches to fit new INA 420 0001 100 lifters originally used in a 1991 Mercedes. These lifters are completely different than the remanufactured 944 INA lifters that have been widely condemned. Boring out the lifters is a very common modification on domestic vehicles and is currently being endurance tested in a few 944 race cars. In fact, when I went to drop off my cam tower he happened to be performing the same modification on another customer's tower; I believe this is becoming more common. After 32 years of faithful service, all of our bores are oval-ed and lifters clogged with sludge. Replacing the sealed lifters with serviceable and cheaper ($12) lifters is a win for the community of 944 enthusiasts. In my case, this was a far more elegant solution than buying a used and likely warn cam tower on the cheap. Now I am reassured that all the critical measurements for this cam tower are within spec (with the exception of the camshaft stuff). The new lifters did require the installation of lash caps. The purpose of this post is just to say it is possible with the addition of lash caps to use the INA 420 0001 100 lifters in a 944. I will link some photos and a video of my car idling with the lifters for those that are interested.
I do plan on going into greater depth on the installation and updating this thread with my experience with the new lifters. As of right now I have put 100 miles on them and am very happy with the results and added peace of mind.
FYI the video was taken on a cold engine, so a bit more lifter noise is expected under those conditions. I tried to vary the throttle a bit for the video.
(I could not upload the video to car pokes for some reason, I will work on that but for now here is a youtube link)
Saw some members were interested in replacing their original lifters and thought I would share some of the work I had done. I initially began this endeavor after I had discovered deep scratches in one of my lifter bores when replacing my head gasket. I briefly considered having the damaged bore welded then re-bored to original spec but was told by multiple professionals that welding a bearing surface was a bad idea. This is when I contacted the machinist that had rebuilt my cylinder head. He is a 944 savant and a true car guy. When I first visited his shop he had dozens of 944 cylinder heads and a few blocks that he was working on, needless to say, I trust the man's judgment. He suggested performing a modification were he would expand the lifter bores from 1.496 to 1.575 inches to fit new INA 420 0001 100 lifters originally used in a 1991 Mercedes. These lifters are completely different than the remanufactured 944 INA lifters that have been widely condemned. Boring out the lifters is a very common modification on domestic vehicles and is currently being endurance tested in a few 944 race cars. In fact, when I went to drop off my cam tower he happened to be performing the same modification on another customer's tower; I believe this is becoming more common. After 32 years of faithful service, all of our bores are oval-ed and lifters clogged with sludge. Replacing the sealed lifters with serviceable and cheaper ($12) lifters is a win for the community of 944 enthusiasts. In my case, this was a far more elegant solution than buying a used and likely warn cam tower on the cheap. Now I am reassured that all the critical measurements for this cam tower are within spec (with the exception of the camshaft stuff). The new lifters did require the installation of lash caps. The purpose of this post is just to say it is possible with the addition of lash caps to use the INA 420 0001 100 lifters in a 944. I will link some photos and a video of my car idling with the lifters for those that are interested.
I do plan on going into greater depth on the installation and updating this thread with my experience with the new lifters. As of right now I have put 100 miles on them and am very happy with the results and added peace of mind.
FYI the video was taken on a cold engine, so a bit more lifter noise is expected under those conditions. I tried to vary the throttle a bit for the video.
(I could not upload the video to car pokes for some reason, I will work on that but for now here is a youtube link)
