Experiment: Cam Motion Low Lash Solid Roller with stock rocker arms
#141
Good news is I was planning to go through it over the winter because the 3rd gear clutches were having some issues from being run with not enough fluid. Found out the hard way my Lokar dipstick I got used was not accurate as far as level. By the time I figured out why it was frequently having issues on a long pull from a stop to 3rd they had been slipped a lot. A couple of them were metal on metal.
Most of the trans was built in 2009 and still looked great. In 2013 I had a converter failure that broke the pump so I replaced the pump, seals, and 3/4 clutch set but put the rest back together as is.
This time we did a full overhaul with new bushings, all clutch sets, new sprags, new low/reverse roller clutch, new drum, and new wide carbon band.
I can try to get a pic of the band itself next week if my dad didn't chunk it.
Basically I was getting ready to do a highway run with a turbo silverado and pulled into the median to turn around and head the opposite way on the highway but he missed the turn so I was getting back onto the road in front of some upcoming traffic. Tires spun so I lifted and pedaled it, thought I got traction back and went heavy throttle and the cabin of the car filled with smoke...appears the trans was about to shift to 2nd when I originally lifted and doing so caused some sort of pile up. It worked ok the rest of that day but started slipping going into 3rd even worse.
The next day I drove it and it felt like sometimes it was either slipping 1st or trying to leave a stop in 2nd. After a bit of a drive I tried to do a quick high throttle pull and when it shifted to 2nd it smoked again instead of grabbing.
I parked it and pulled it after that.
On disassembly the servo was stuck in the case and took a lot of effort to remove.
Most of the trans was built in 2009 and still looked great. In 2013 I had a converter failure that broke the pump so I replaced the pump, seals, and 3/4 clutch set but put the rest back together as is.
This time we did a full overhaul with new bushings, all clutch sets, new sprags, new low/reverse roller clutch, new drum, and new wide carbon band.
I can try to get a pic of the band itself next week if my dad didn't chunk it.
Basically I was getting ready to do a highway run with a turbo silverado and pulled into the median to turn around and head the opposite way on the highway but he missed the turn so I was getting back onto the road in front of some upcoming traffic. Tires spun so I lifted and pedaled it, thought I got traction back and went heavy throttle and the cabin of the car filled with smoke...appears the trans was about to shift to 2nd when I originally lifted and doing so caused some sort of pile up. It worked ok the rest of that day but started slipping going into 3rd even worse.
The next day I drove it and it felt like sometimes it was either slipping 1st or trying to leave a stop in 2nd. After a bit of a drive I tried to do a quick high throttle pull and when it shifted to 2nd it smoked again instead of grabbing.
I parked it and pulled it after that.
On disassembly the servo was stuck in the case and took a lot of effort to remove.
#142
TECH Senior Member
looks like drum got hot from band riding on it...
the 2nd servo not only applies the band for 2nd gear, but it also is the accumulator for 3rd... so it probably also took out 3rd gear... so you got 3 gears gone in one event.
the 2nd servo not only applies the band for 2nd gear, but it also is the accumulator for 3rd... so it probably also took out 3rd gear... so you got 3 gears gone in one event.
#144
Best guess is when I nailed it and spun it was very close to the full throttle shift point RPM wise (shifter was in 3rd or D position) because the engine revs like mad in first once the tires let loose.
I must have lifted at the moment it was going to shift to 2nd. From there I am pretty sure I rolled back hard on the throttle and that's when the smoke let out.
As far as why it would have hung, not sure. There was no scoring or any burring in the case or on the servo. The servo o ring might have somehow rolled out of the groove and jammed between the case and the servo is my best guess given the condition of the parts. We inspected all the hard parts and the case very well during clean up and found no other mechanical issues.
#145
Just another update since track opening day is sneaking up on me I went ahead and gave everything a pre-season inspection.
I ended up just making sure cold lash was still .000" to slightly preloaded. Happy to say everything was still nice and tight. I had a lot of other things to look over on the car and didn't want to get everything hot before doing so.
The valve stem tips do not show any signs of abnormal wear (the ones we ground still show machine marks) or damage.
The rockers with the BTR trunions move nice and smooth but everything feels like new with no drag or slop.
I had been considering looking into some adjustable rockers and valve covers but honestly as zero maintenance as this setup is I will just put that money towards getting the car painted this summer instead.
After this race season it should be time to replace the BTR springs with a fresh set and keep on rolling.
I'll update this thread again once I get some track passes next month. Previous best with the bad fueling in the tune was 11.33, I'd like to see some 11.20s from it before I make changes to the car (suspension tweaks, create a cold air box, other odds and ends).
I ended up just making sure cold lash was still .000" to slightly preloaded. Happy to say everything was still nice and tight. I had a lot of other things to look over on the car and didn't want to get everything hot before doing so.
The valve stem tips do not show any signs of abnormal wear (the ones we ground still show machine marks) or damage.
The rockers with the BTR trunions move nice and smooth but everything feels like new with no drag or slop.
I had been considering looking into some adjustable rockers and valve covers but honestly as zero maintenance as this setup is I will just put that money towards getting the car painted this summer instead.
After this race season it should be time to replace the BTR springs with a fresh set and keep on rolling.
I'll update this thread again once I get some track passes next month. Previous best with the bad fueling in the tune was 11.33, I'd like to see some 11.20s from it before I make changes to the car (suspension tweaks, create a cold air box, other odds and ends).
#146
Super Hulk Smash
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Nice to hear!
I am about to go through mine. I have rattles and stuff from my torque arm, true duals, and the tran relo all hating each other. Once I get that cleared up, I'll be taking it to the track as well. Working on a return to idle glitch at the moment... whee.
I am about to go through mine. I have rattles and stuff from my torque arm, true duals, and the tran relo all hating each other. Once I get that cleared up, I'll be taking it to the track as well. Working on a return to idle glitch at the moment... whee.
#147
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Just another update since track opening day is sneaking up on me I went ahead and gave everything a pre-season inspection.
I ended up just making sure cold lash was still .000" to slightly preloaded. Happy to say everything was still nice and tight. I had a lot of other things to look over on the car and didn't want to get everything hot before doing so.
The valve stem tips do not show any signs of abnormal wear (the ones we ground still show machine marks) or damage.
The rockers with the BTR trunions move nice and smooth but everything feels like new with no drag or slop.
I had been considering looking into some adjustable rockers and valve covers but honestly as zero maintenance as this setup is I will just put that money towards getting the car painted this summer instead.
After this race season it should be time to replace the BTR springs with a fresh set and keep on rolling.
I'll update this thread again once I get some track passes next month. Previous best with the bad fueling in the tune was 11.33, I'd like to see some 11.20s from it before I make changes to the car (suspension tweaks, create a cold air box, other odds and ends).
I ended up just making sure cold lash was still .000" to slightly preloaded. Happy to say everything was still nice and tight. I had a lot of other things to look over on the car and didn't want to get everything hot before doing so.
The valve stem tips do not show any signs of abnormal wear (the ones we ground still show machine marks) or damage.
The rockers with the BTR trunions move nice and smooth but everything feels like new with no drag or slop.
I had been considering looking into some adjustable rockers and valve covers but honestly as zero maintenance as this setup is I will just put that money towards getting the car painted this summer instead.
After this race season it should be time to replace the BTR springs with a fresh set and keep on rolling.
I'll update this thread again once I get some track passes next month. Previous best with the bad fueling in the tune was 11.33, I'd like to see some 11.20s from it before I make changes to the car (suspension tweaks, create a cold air box, other odds and ends).
#149
FWIW - a little trick to cheat another degree or two duration out of the cam. Preload your valves by 0.003". Basically, you're at 0.000. Remove 0.002" of shim. it'll make cold starts and running just a tad rougher, but when it warms up, you'll have less hot lash, so your durations at 0.006, 0.050, 0.200, etc all gain about 2-3 degrees.
This is not completely correct. When tightening lash, the seat timing or timing at .006" will increase in duration at the valve about 4x as much as it will at .050" and even less at .200" This is because the ramp is much slower near the seat than it is at .050" .100", .200" etc.. So, while tightening the lash will make a camshaft slightly larger at .050", it will increase the seat timing substantially more which may not be desirable and can cause loss of lower RPM torque. So, when experimenting with changes in lash, you may not always get the performance result that you expect. You just have to try it and see how your particular engine responds.
Also, if going looser, try not to go any looser than about 4 degrees more than the camshaft is designed for. This is because as the lash gets looser, the lifter engages the camshaft lobe at a faster or more aggressive part of the lobes ramp. This can be hard on or parts or even lead to breakage.
~Steven
#150
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10-4. Appreciate the correction. Mine liked it and I assumed that the result would be universal
#151
Recently I had the engine out due to a busted H3 oil pan. While it was out I decided to knock out another lash check.
Out of all 16 I made the following changes:
2 valves I removed .001" shim
2 valves I removed .002" shim
1 valve I removed .004" shim
I also inspected the valve tips of all of those pairs as they were off. Absolutely no abnormal wear or anything unusual.
Needless to say I still feel this is a great low cost alternative for those with street/strip cars that want to go low lash solid roller without the added expense of rocker arms and valve covers. An extra hour or 2 per year to keep an eye on things is well worth it to me.
EDIT: Unfortunately due to life circumstances I have not been racing since this post was updated at the beginning of the year. I was hoping to go in the cool November air before the track closed but I lost my job at the end of September and have not found work again yet. Here's hoping for a better season next year.
Out of all 16 I made the following changes:
2 valves I removed .001" shim
2 valves I removed .002" shim
1 valve I removed .004" shim
I also inspected the valve tips of all of those pairs as they were off. Absolutely no abnormal wear or anything unusual.
Needless to say I still feel this is a great low cost alternative for those with street/strip cars that want to go low lash solid roller without the added expense of rocker arms and valve covers. An extra hour or 2 per year to keep an eye on things is well worth it to me.
EDIT: Unfortunately due to life circumstances I have not been racing since this post was updated at the beginning of the year. I was hoping to go in the cool November air before the track closed but I lost my job at the end of September and have not found work again yet. Here's hoping for a better season next year.
#152
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Thanks for updating this man. Sorry to hear stuff not going so great.
How many miles on the LLSR now?
How many miles on the LLSR now?
#155
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Thought I would bump this thread, since the topic of LLSR and stock rockers keeps coming up. This is an excellent how-to and explanation of how everything works together. Probably sticky-worthy, but there are a lot of stickies already in this section
#157
I had a PM in regards to the thread so I thought I would chime in to say everything is still par for course and nothing abnormal has risen.
Life got even more complicated so still no more racing and honestly very little driving the car in general but I did take it on a couple several hour long cruises in the spring and the LLSR continues to be maintenance free and a pleasure to drive.
If anything odd ever does come about I will be sure to post details. At this point the setup had more than proved it's worth for the intended purpose enough to call it a great success IMO. I would do it again without hesitation and I don't see myself ever investing the extreme expense of shaft mount rockers and taller valve covers for my particular application.
Life got even more complicated so still no more racing and honestly very little driving the car in general but I did take it on a couple several hour long cruises in the spring and the LLSR continues to be maintenance free and a pleasure to drive.
If anything odd ever does come about I will be sure to post details. At this point the setup had more than proved it's worth for the intended purpose enough to call it a great success IMO. I would do it again without hesitation and I don't see myself ever investing the extreme expense of shaft mount rockers and taller valve covers for my particular application.
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#160
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