[clg82]

Hey everyone about ready to pull the trigger on a BMR rear lockout kit. Can I back my car (safely) onto my set of raceramps and do the install that way? Or does the weight have to be off wheels? Fairly simple question so apologies for the newb question.

[PROMETHEUS]

I had mine done by a performance shop, sorry can't help.

[MatthewAMEL]

Originally Posted by clg82

Hey everyone about ready to pull the trigger on a BMR rear lockout kit. Can I back my car (safely) onto my set of raceramps and do the install that way? Or does the weight have to be off wheels? Fairly simple question so apologies for the newb question.

You want weight off the wheels.


And you want it level. Part of the install is loosening the cradle so it droops enough to reach the top of the bushings. If when you loosen them, they droop and shift front/rear (due to sloped car), you'll have a really tough time getting the holes to line up.


Also, don't believe them when BMR says you can just press in the 'bullets' with your fingers. Unless you have Hulk thumbs. I had to semi-press them in with help from a floor jack.

[MP3BOOSTED]

Following, about to do the install myself.

[radz28]

I just did the ZLE bushings, and as these aren't exactly as intensive, I would add that you should try to get the car as high as safely possible. I used relatively small ramps to elevate the front (maybe 6" ramps or something), and chocked them so they wouldn't allow the car to roll forward or backward off the ramps. PAY ATTENTION TO THIS, as I almost overlooked that issue. Then - I used a pair of stands to get the rear of the car probably 12" higher. I supplemented all that with a few 3-ton jacks to compress/position/etc. what I needed to when I needed to. I forget what comes with that kit, but the cradle mount bolts are TTY, so you should replace those. Perhaps you could get away with reuse, but... And - perhaps consider an alignment when you're done. Maybe the instructions say you don't need one, and maybe you don't, but do you want to chew through a set of tires to fine that out?

Have fun. This should be a nice project.

[cdrptrks]

I just did the BMR BK063 lockout kit install myself a few days ago on my SS 1LE. I took the rear wheels off and it was very helpful to get access to insert the black delrin lockouts. I am not sure why that is not part of the instructions. It took me more than the 2-3 hour estimate mostly because BMR's instructions did not work for me using floor jacks and I took some extra time to mark the new GM bolts that I installed along with the nuts that I reused so I can see at a glance if any of them start to come loose in the future. It seems like BMR never actually tried following their own directions using floor jacks or else maybe they left out some detail(s) that make it easier which were not obvious to me as a shadetree mechanic. General tip for torqueing bolts like these 4: use a floor jack handle for leverage on a 1/2" wrench or breaker bar to do the angle portion after reaching the initial ft/lbs value with the torque wrench.

In order to complete step 4 [insert the front upper black Delrin lockouts], after removing front cradle braces and both 18mm front cradle bolts, I also had to remove the rear 2x15mm nuts (BMR's instructions incorrectly call them 15mm and 18mm nuts) and the rear cradle brace that they held on and then loosen one 18mm rear cradle bolt at a time in order to get enough space to insert the front upper black Delrin lockouts. Before doing that, I tried completely lowering the floor jack until it was not supporting the diff pumpkin at all, plus I tried using my longest pry bar to increase the front gap but those were not enough. Their directions also skipped removing one T15 torx bolt per side that attach to the rear wheel well liner. It is not possible to remove the front cradle braces without doing this but you are supposed to remove them in steps 2/3. The instructions also didn't mention that you will need some 3/8" or 1/2" extensions to reach some of the nuts; thankfully I already had some in my toolbox. I think I used a 9" for removing and re-torqueing one of the rear cradle brace nuts.

Originally Posted by MatthewAMEL

And you want it level. Part of the install is loosening the cradle so it droops enough to reach the top of the bushings. If when you loosen them, they droop and shift front/rear (due to sloped car), you'll have a really tough time getting the holes to line up.

I didn't find this particular thread until after my install, but I didn't have a problem lining up the holes with only the back of the car jacked up. I just gave the floor jack under the diff pumpkin a few pumps to raise it back up at that point. I initially tried putting the front wheels on ramps but the jack stand location I needed to use on the pinch welds by the back of the door in order to have clearance to remove the front cradle braces was causing the front wheels to lift off of the ramps when I lowered the floor jack so I removed the ramps.

Originally Posted by MatthewAMEL

Also, don't believe them when BMR says you can just press in the 'bullets' with your fingers. Unless you have Hulk thumbs. I had to semi-press them in with help from a floor jack.

Yes I ended up doing something similar...used a spare piece of 2x4 with a floor jack to push the bullets in. With a generous amount of silicone based brake lube that I had sitting around (make sure to pick a grease/lube that is compatible with rubber), some of them still would not go in far enough to get the bolts started even when using a hammer. The exhaust hangers make it hard to hit them with a hammer and the hammer didn't provide enough force anyways.

My initial impression on stock SC3 tires after the equivalent of about one 20 minute session at my local track today (MSR Houston) in a track sprint event is that oversteer starts a bit more gradually. I usually drive with traction/stability control off because it gives me the best feel for what back of the car is doing; not sure if PTM might make this less noticeable. Also I just drove this track in this direction for one long session in December and at another event with 4 sessions in one day at the end of January so I have a recent memory of what the car felt like before and I reviewed PDR data/videos from those events before today's event. I don't have lap time comparisons because the track sprint format today involved doing about 80% of a the distance of a lap and waiting a few minutes for others to go one at a time before going again. I think the lockout kit might make more of a difference the next time I try my ZLE wheels with 100 treadwear SC3R tires since the car was previously more of a handful for me on track with those tires. On the highway I notice that I feel expansion joints and transitions to/from overpasses more sharply in my back/butt than I did before, but it is not a big a difference in terms of comfort. I also noticed feeling some minor back and forth motion while I had cruise control set that I have not felt before on certain slightly uneven road surfaces (on a stretch of highway that I drive a lot) but it was pretty minor and didn't last very long. When launching the car from a stop and from a roll, it felt like I might be able to go to 100% throttle in first gear more quickly without spinning the tires and/or engaging traction control compared to before but it is still possible to spin them. It is difficult to say for sure since road and tire temperature also impact this. I went to the 1/4 mile drag strip once a while back with the same type/size of tires and the same rear alignment that I have now so maybe I will go back and compare 60' times before/after.

Note: I didn't get the alignment checked yet, but the car continued to track straight like it did before on throttle and under heavy braking and felt fine on track so I would guess that the alignment didn't change much if any. I will post again once I get an alignment check after I install the FEA front lower front links to replace my FE4 links that leaked their hydraulic fluid out a while back.