3900 Cam Bearing Spacers

[SappySE107]

Several people have had them made, but I don't know what cam/journal clearance they end up with after the spacers are installed and the bearings installed. ID and OD measurements basically, for the spacer. This was the first one I had made. The 2nd is still in the block as I need to get it on a table to knock it back out. ID was wrong on that one so I couldn't test fit a bearing. Should I get a 3900 cam bearing set and use those measurements for the OD? I don't know the compression rate, from press fitting them into the block vs the new ID vs old ID.

[SappySE107]

No help and no progress to report.

[SappySE107]

Got some help. I will get the specs finalized along with the design and see about getting a set made.

[jdv]

Hi Sappy any progress on the cam spacers

[SappySE107]

I have a place that will make them in quantity, but I want to have 2 more test spacers made. The set I had made, because I thought I had it down, feels loose. I want to see what it takes to not fit the cam so I know the clearances. Money has been pretty tight since race season isn't happening, cams aren't available, ARP studs just got restocked, etc. Its picked up a little this month and now that I have a great source for making them, its back on track.

[jdv]

That is good to hear. Glad to see work picking back up. I want to do an other v6 swap and this looks like the best option.

[v2rocket]

As an alternative, could the custom-made hot cams for the 3x00 engines be manufactured with the LZ4/9 cam journal diameter?
I am imagining welding up the journals and grinding to size like a crankshaft repair. Obviously more cost but then you just use stock LZ4/9 bearings/clearance.

[v2rocket]

Rather than bearing spacers, or weld/grinding, how about having shrink-fit rings made up to just take up the space between the 3x00 cam journal and the LZ4/9 stock bearings?

It's nearly the same machining work as the spacers, without having to mess around with a bearing install tool. Just buy hot cam, stick in freezer, put slip rings in oven, fit over journals and let temperature normalize and they are stuck in place like a wheel bearing in a hub.

There are some loctite products made for this type of work (shrink fit stuff, like cylinder sleeves) as extra insurance if desired.

[SappySE107]

https://wot-tech.com/cam-bearing-spacer-set.html