The Rubi Q Build

[UNSTUCK]

Did either of you run more than just drive and manual shift from your shift lever? As I understand it, you can use the shift detents beyond drive and manual shift to run other programmed shift modes. I think I’m going to try to use a TJ 3 speed auto shifter to give me normal drive, manual shift, and then a programmed sport mode from a corvette with much more aggressive shifting and rev matching.

 

[zmotorsports]

I just ran two forward modes, normal Drive (D) and the Manual (M) gate which is one down from Drive. In my 2011 shift console it is labeled at "2" where second gear used to be with the 42RLE transmission. Once in the Manual gate then I use a toggle switch that I mounded next to the steering column to tap-shift up or down through the forward gears. Love that features and use it almost exclusively off-road unless on a relatively level fire road.

 

[RockChucker]

I have a Winters shifter modified with microswitches. Only use 2 positions. D and M. I have my shift parameters set to make it impossible for the computer to shift the trans unless I change gears. I can cruise along in 5th gear, come to a stop and leave in 5th gear if I wanted too. I behaves like a full manual sequential gear box. There are safeties in place to prevent mechanical over-revving the engine. Meaning I can't downshift into 1st at 60 mph. It will automatically upshift in that scenario.

 

[UNSTUCK]

How are you keeping track of what gear you're in when in M mode? I've been looking at different little screens that display the gear it's in. Don't really like any of them, as far a integrating them into the dash and keeping it clean.

 

[zmotorsports]

How are you keeping track of what gear you're in when in M mode? I've been looking at different little screens that display the gear it's in. Don't really like any of them, as far a integrating them into the dash and keeping it clean.

Mine is tied into the OEM's dash indicator through the interior CAN network,m connected through the BCM. I used an aftermarket (Motech) CANbus module to create the handshake between the GM ECM and the Chrysler BCM to have all controls work properly. The OEM HVAC controls and even the steering wheel controls function as designed by Chrysler.

 

[RockChucker]

I have a PCS indicator that pulls info off the CAN bus. Not ideal but my “ancient” Jeep doesn’t have the fancy features Mike has in his JK. If I was smart, when I built my motor I would have put a 58x reluctor wheel on the crank and converted my harness or redone it with a Gen iv setup. Then I would have strongly looked at running something like an edge or banks monitor for gear shift indicating. In addition to other things that would be able to monitor like fuel consumed since last fill up, trans temp etc. My PCS trans controller won’t communicate with devices like that unfortunately.

 

[UNSTUCK]

I'm pretty stuck on the camshaft choice. Speaking with both TSP and Michigan motorsports they are both pushing pretty different cams to me.

Michigan wants me to get this one:

Brian Tooley BTR Torque Camshaft Truck Cam Kit 4.8 5.3 6.0 6.2 LS LS1 LM7 LQ4

BTR TRUCK TORQUE CAMSHAFT Specs: 20x/20x .50x"/.50x" 111-1 Doing some heavy lifting with your 99-13 GM Truck? Want to get the most out of the low-end RPM range? Want to save the time and hassle of changing out your OEM Torque Converter? Do you want to be able to remove redwood stumps with a...

www.michiganmotorsports.com

TSP wants me to get this one:

Texas Speed TSP Stage 3 High Lift Truck Camshaft LS 4.8 5.3 6.0 6.2 1999-2013 Single Spring Cam kit

Michigan Motorsports specializes in LS1 performance Parts, LS3 Rocker Arm Trunions, Electrial harnesses and adapters, and Diesel Parts

www.michiganmotorsports.com

TSP is selling theirs better. They say the 6.2 needs the higher lift and durations. With the VVT on the stock engine it's hard to really know how these compare to stock. Most of the dyno charts show numbers from a 5.3. Should I expect the 6.2 to have a similar graph, only maybe higher numbers? The BTR is $150 cheaper. That's significant at this point. The BTR is said to have better numbers down low, but dies out sooner, but still above my desired redline. I don't care what power these make at 6500+ rpms.

What do you think?

 

[Greg]

I'm pretty stuck on the camshaft choice. Speaking with both TSP and Michigan motorsports they are both pushing pretty different cams to me.

Michigan wants me to get this one:

Brian Tooley BTR Torque Camshaft Truck Cam Kit 4.8 5.3 6.0 6.2 LS LS1 LM7 LQ4

BTR TRUCK TORQUE CAMSHAFT Specs: 20x/20x .50x"/.50x" 111-1 Doing some heavy lifting with your 99-13 GM Truck? Want to get the most out of the low-end RPM range? Want to save the time and hassle of changing out your OEM Torque Converter? Do you want to be able to remove redwood stumps with a...

www.michiganmotorsports.com

TSP wants me to get this one:

Texas Speed TSP Stage 3 High Lift Truck Camshaft LS 4.8 5.3 6.0 6.2 1999-2013 Single Spring Cam kit

Michigan Motorsports specializes in LS1 performance Parts, LS3 Rocker Arm Trunions, Electrial harnesses and adapters, and Diesel Parts

www.michiganmotorsports.com

TSP is selling theirs better. They say the 6.2 needs the higher lift and durations. With the VVT on the stock engine it's hard to really know how these compare to stock. Most of the dyno charts show numbers from a 5.3. Should I expect the 6.2 to have a similar graph, only maybe higher numbers? The BTR is $150 cheaper. That's significant at this point. The BTR is said to have better numbers down low, but dies out sooner, but still above my desired redline. I don't care what power these make at 6500+ rpms.

What do you think?

A power curve for a smaller engine (5.3) is going to move lower in the chart for a larger engine (6.2) with the same camshaft.

I'd go with the BTR cam myself, for a Jeep it'll make good off-idle torque, doesn't require a higher stall convertor (making added heat) and still have plenty of top-end for your needs.

 

[Pile of parts]

I'd check youtube and see if Richard Holdener has done any tests on the 6.2. I've been watching him a lot as try to figure out what I want to do with the 5.3 for my '49 GMC. I like his tests and reviews. I'm with you, not looking to squeeze out the last little bit in the high rpms.

 

[UNSTUCK]

I really like his videos as well. I think I’ve watched most of his relating to the ls3/l92. I don’t think I’ve seen a dyno graph even start below 3000. I think in a rock crawler the 2000-3000 is an important range. And then I don’t care what happens to the graph above about 5500. Good luck finding a video that shows that info.

 

[lhracing]

I would pick a camshaft that has good torque at my highway cruise rpm and has peek hp around my projected max rpm. Something to consider is valve lift, more lift increases valve spring temperatures and can reduce their life.

 

[UNSTUCK]

I would pick a camshaft that has good torque at my highway cruise rpm and has peek hp around my projected max rpm. Something to consider is valve lift, more lift increases valve spring temperatures and can reduce their life.

My engine will be humming along at about 1850 RPMs at 70 MPH and then 1950 when I change tires and axle ratios, a bit down the road. There's no charts that show my engine and those RPM's so it's definitely a guess.


Here's my list at Michigan. What do you think? What am I missing?

Michigan Motorsports - Wish Lists

Michigan Motorsports specializes in LS1 performance Parts, LS3 Rocker Arm Trunions, Electrial harnesses and adapters, and Diesel Parts

www.michiganmotorsports.com

 

[1969honda]

.600' is a ton of lift and spring pressure to get the valve closed again. I'm guessing here, but it seems to me the lobes would have a really aggresive ramp profile to match that lift. In my mind that is not the best recipe for longevity.

If the two cams mentioned are the only options I would go with the .511" BTR. The smaller LS engines have a habit of breaking stock springs with less than .500" lift. I've even seen a few LS3 springs fatigue and break at not much more than that BTR cam when pushed to hard.

I know I enjoy the mental exercise of matching up engine combos, but have you consulted your machinist yet? They might have a totally different recommendation and experience that better fits your application.

 

[lhracing]

My engine will be humming along at about 1850 RPMs at 70 MPH and then 1950 when I change tires and axle ratios, a bit down the road. There's no charts that show my engine and those RPM's so it's definitely a guess.


Here's my list at Michigan. What do you think? What am I missing?

Michigan Motorsports - Wish Lists

Michigan Motorsports specializes in LS1 performance Parts, LS3 Rocker Arm Trunions, Electrial harnesses and adapters, and Diesel Parts

www.michiganmotorsports.com

I think that cam would be a good choice, it should provide close to 300 ft/lbs at 2000 rpm (the 4.0 at 2000 is about 180 ft/lbs) and with .511 valve lift the springs should live a long time. I looked at my engine simulation software and it's old enough to not have much for LS engines (I mostly built big block chevy's). If you had flow numbers for the heads, the bore/stroke, intake cfm flow and compression I could put the values in and get you a close estimate for this combination.

 

[UNSTUCK]

Not a bad way to spend $1600.


The engine is waiting for its turn at the machine shop right now. I expect it to be another month or so and praying everything is fine with it and the machine work will be insignificant.

The 6L80E got rebuilt last week. I knew there was a crack in the side of the bell housing where the front driveshaft hit it at some point. I was planning on welding it. The trans builder advised against it saying they have attempted that repair a few times in the past with poor success as it messes up the pump section that’s part of the bell housing. So I got a new one. Also got a billet front cover torque converter and “stage one” internals. That set me back $3000.

I still need to get parts to rebuild the tcase and SYE.

 

[RockChucker]

First thing I'd recommend doing when you get your block back is to check cam bearing clearances. I had the machine shop install new bearings in my block when I was building my engine. The clearances were "in spec" at the very loosest side. They said there was nothing they could do about it, so I found some undersized bearings and said they could do something about it. I ended up having to have them grind the journals on the cam, but I ended up with good specs that weren't going to leave me with a brand new engine with no oil pressure. I'm sure this isn't your first rodeo, but wanted to highlight one of the thorns in my side when I was building mine.

 

[UNSTUCK]

Thanks for the heads up. I’ll be sure to check. Remind me in 6 weeks. 😂

 

[UNSTUCK]

NP241c Tech, and all my dilemmas:

I'm pretty sure my 241c has low miles on it. When I put it in 4wd there is very little play in the chain, like maybe 1/8 of a turn of the front output while holding the input shaft still. There is fresh RTV all over the mating surfaces. Putting a bore scope inside shows everything to be clean, blue wear pads (which I think is a new color?), and nothing scary looking. My plan is to buy a Tom Woods SYE kit and a front CV output yoke and run it. Well, almost...

The big problem is, well, it isn't a 241j. Remember I'm going for ultimate sleeper LS swap here. This 241c shifts 4hi, 2, N, 4lo. That means I would have to run around with the t-case shifter in the 4hi position when it's in 2wd. NO GOOD!
The other, slightly less big, problem is the 4x4 switch is pretty complex on the 241j. It sends a signal in each position, not just 2wd or 4wd. This may not matter now that I have bypassed my locker switches to work in any gear. I think I can get the 241c switch to just turn the dash light on. But I still want to tell the GM ECM when I'm in 4lo for optimal shift programing in that range. I will use the GM VSS and a DD converter to send the right signals to the dash for speedo and tach. I'll tie into the speedo signal to feel that info to the ECM.

So..... I believe there are other 241Cs that have the proper shift pattern. Can I swap the needed parts into my 241 and get the shifting I want? Even better, Ebay has all the parts from a 241j. If I got the shift cam, mode and range fork, would that let it work? That would let me use the 241j 4x4 switch and give me the shift pattern I want. I would be assuming the threaded hole in the case is the same. I need to figure that out too. But I do know the 241j 4x4 switch (Mopar #5083138AA) was used in JKs, WJs, Libertys, and Ram 1500-5500 trucks. So they would all use the same shift cam but I don't know about shift pattern. I bet the WJ would be the same as the TJ/LJ.

I'm junk yard diving on Saturday to see what I can find. Am I on the right track?

 

[zmotorsports]

Is there a reason you don't want to use a 241J TC? When I did my LS swap the goal was also building a sleeper with nothing in your face per se and keeping with all OEM or OE parts for availability and to minimize any proprietary parts sourcing as much as possible.

When it came to the transfer case, I sold my Rubicon (241OR) and found a low mileage 241J from a Sahara then just swapped the input shaft to fit the GM splines on the 6L80. It's been working perfectly for 65k miles now and fully integrates with the OEM BCM for the four-wheel dash lights and communications with the GM E38 computer for shift optimization when in 4WD.

 

[UNSTUCK]

Well that’s a dang good question. I was under the impression that there really is no np241or. That was kind of a nickname for the Rubi case as jeep called the Rubi package the Off Road package. Anyways, my 4:1 Rubi case is stamped as a 241j and I know I can’t swap the input shaft on it to 32 spline. Are you saying there is a 4:1 and a 2:1 241j? Finding one of those is the way to go.